2005-04-17 06:20:36 +08:00
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/*
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* Driver for Zilog serial chips found on SGI workstations and
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* servers. This driver could actually be made more generic.
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*
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* This is based on the drivers/serial/sunzilog.c code as of 2.6.0-test7 and the
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* old drivers/sgi/char/sgiserial.c code which itself is based of the original
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* drivers/sbus/char/zs.c code. A lot of code has been simply moved over
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* directly from there but much has been rewritten. Credits therefore go out
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* to David S. Miller, Eddie C. Dost, Pete Zaitcev, Ted Ts'o and Alex Buell
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* for their work there.
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*
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* Copyright (C) 2002 Ralf Baechle (ralf@linux-mips.org)
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* Copyright (C) 2002 David S. Miller (davem@redhat.com)
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/delay.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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#include <linux/major.h>
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#include <linux/string.h>
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#include <linux/ptrace.h>
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#include <linux/ioport.h>
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#include <linux/slab.h>
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#include <linux/circ_buf.h>
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#include <linux/serial.h>
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#include <linux/sysrq.h>
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#include <linux/console.h>
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#include <linux/spinlock.h>
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#include <linux/init.h>
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#include <asm/io.h>
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#include <asm/irq.h>
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#include <asm/sgialib.h>
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#include <asm/sgi/ioc.h>
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#include <asm/sgi/hpc3.h>
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#include <asm/sgi/ip22.h>
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#if defined(CONFIG_SERIAL_IP22_ZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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#define SUPPORT_SYSRQ
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#endif
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#include <linux/serial_core.h>
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#include "ip22zilog.h"
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/*
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* On IP22 we need to delay after register accesses but we do not need to
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* flush writes.
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*/
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#define ZSDELAY() udelay(5)
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#define ZSDELAY_LONG() udelay(20)
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#define ZS_WSYNC(channel) do { } while (0)
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#define NUM_IP22ZILOG 1
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#define NUM_CHANNELS (NUM_IP22ZILOG * 2)
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#define ZS_CLOCK 3672000 /* Zilog input clock rate. */
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#define ZS_CLOCK_DIVISOR 16 /* Divisor this driver uses. */
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/*
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* We wrap our port structure around the generic uart_port.
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*/
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struct uart_ip22zilog_port {
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struct uart_port port;
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/* IRQ servicing chain. */
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struct uart_ip22zilog_port *next;
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/* Current values of Zilog write registers. */
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unsigned char curregs[NUM_ZSREGS];
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unsigned int flags;
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#define IP22ZILOG_FLAG_IS_CONS 0x00000004
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#define IP22ZILOG_FLAG_IS_KGDB 0x00000008
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#define IP22ZILOG_FLAG_MODEM_STATUS 0x00000010
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#define IP22ZILOG_FLAG_IS_CHANNEL_A 0x00000020
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#define IP22ZILOG_FLAG_REGS_HELD 0x00000040
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#define IP22ZILOG_FLAG_TX_STOPPED 0x00000080
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#define IP22ZILOG_FLAG_TX_ACTIVE 0x00000100
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2007-11-29 08:21:44 +08:00
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#define IP22ZILOG_FLAG_RESET_DONE 0x00000200
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2005-04-17 06:20:36 +08:00
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2007-11-29 08:21:44 +08:00
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unsigned int tty_break;
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2005-04-17 06:20:36 +08:00
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unsigned char parity_mask;
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unsigned char prev_status;
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};
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#define ZILOG_CHANNEL_FROM_PORT(PORT) ((struct zilog_channel *)((PORT)->membase))
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#define UART_ZILOG(PORT) ((struct uart_ip22zilog_port *)(PORT))
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#define IP22ZILOG_GET_CURR_REG(PORT, REGNUM) \
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(UART_ZILOG(PORT)->curregs[REGNUM])
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#define IP22ZILOG_SET_CURR_REG(PORT, REGNUM, REGVAL) \
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((UART_ZILOG(PORT)->curregs[REGNUM]) = (REGVAL))
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#define ZS_IS_CONS(UP) ((UP)->flags & IP22ZILOG_FLAG_IS_CONS)
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#define ZS_IS_KGDB(UP) ((UP)->flags & IP22ZILOG_FLAG_IS_KGDB)
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#define ZS_WANTS_MODEM_STATUS(UP) ((UP)->flags & IP22ZILOG_FLAG_MODEM_STATUS)
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#define ZS_IS_CHANNEL_A(UP) ((UP)->flags & IP22ZILOG_FLAG_IS_CHANNEL_A)
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#define ZS_REGS_HELD(UP) ((UP)->flags & IP22ZILOG_FLAG_REGS_HELD)
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#define ZS_TX_STOPPED(UP) ((UP)->flags & IP22ZILOG_FLAG_TX_STOPPED)
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#define ZS_TX_ACTIVE(UP) ((UP)->flags & IP22ZILOG_FLAG_TX_ACTIVE)
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/* Reading and writing Zilog8530 registers. The delays are to make this
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* driver work on the IP22 which needs a settling delay after each chip
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* register access, other machines handle this in hardware via auxiliary
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* flip-flops which implement the settle time we do in software.
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*
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* The port lock must be held and local IRQs must be disabled
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* when {read,write}_zsreg is invoked.
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*/
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static unsigned char read_zsreg(struct zilog_channel *channel,
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unsigned char reg)
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{
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unsigned char retval;
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writeb(reg, &channel->control);
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ZSDELAY();
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retval = readb(&channel->control);
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ZSDELAY();
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return retval;
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}
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static void write_zsreg(struct zilog_channel *channel,
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unsigned char reg, unsigned char value)
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{
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writeb(reg, &channel->control);
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ZSDELAY();
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writeb(value, &channel->control);
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ZSDELAY();
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}
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static void ip22zilog_clear_fifo(struct zilog_channel *channel)
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{
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int i;
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for (i = 0; i < 32; i++) {
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unsigned char regval;
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regval = readb(&channel->control);
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ZSDELAY();
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if (regval & Rx_CH_AV)
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break;
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regval = read_zsreg(channel, R1);
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readb(&channel->data);
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ZSDELAY();
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if (regval & (PAR_ERR | Rx_OVR | CRC_ERR)) {
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writeb(ERR_RES, &channel->control);
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ZSDELAY();
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ZS_WSYNC(channel);
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}
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}
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}
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/* This function must only be called when the TX is not busy. The UART
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* port lock must be held and local interrupts disabled.
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*/
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static void __load_zsregs(struct zilog_channel *channel, unsigned char *regs)
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{
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int i;
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/* Let pending transmits finish. */
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for (i = 0; i < 1000; i++) {
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unsigned char stat = read_zsreg(channel, R1);
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if (stat & ALL_SNT)
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break;
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udelay(100);
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}
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writeb(ERR_RES, &channel->control);
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ZSDELAY();
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ZS_WSYNC(channel);
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ip22zilog_clear_fifo(channel);
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/* Disable all interrupts. */
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write_zsreg(channel, R1,
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regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
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/* Set parity, sync config, stop bits, and clock divisor. */
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write_zsreg(channel, R4, regs[R4]);
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/* Set misc. TX/RX control bits. */
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write_zsreg(channel, R10, regs[R10]);
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/* Set TX/RX controls sans the enable bits. */
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write_zsreg(channel, R3, regs[R3] & ~RxENAB);
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write_zsreg(channel, R5, regs[R5] & ~TxENAB);
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/* Synchronous mode config. */
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write_zsreg(channel, R6, regs[R6]);
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write_zsreg(channel, R7, regs[R7]);
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/* Don't mess with the interrupt vector (R2, unused by us) and
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* master interrupt control (R9). We make sure this is setup
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* properly at probe time then never touch it again.
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*/
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/* Disable baud generator. */
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write_zsreg(channel, R14, regs[R14] & ~BRENAB);
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/* Clock mode control. */
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write_zsreg(channel, R11, regs[R11]);
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/* Lower and upper byte of baud rate generator divisor. */
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write_zsreg(channel, R12, regs[R12]);
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write_zsreg(channel, R13, regs[R13]);
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2006-02-09 05:43:03 +08:00
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2005-04-17 06:20:36 +08:00
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/* Now rewrite R14, with BRENAB (if set). */
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write_zsreg(channel, R14, regs[R14]);
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/* External status interrupt control. */
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write_zsreg(channel, R15, regs[R15]);
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/* Reset external status interrupts. */
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write_zsreg(channel, R0, RES_EXT_INT);
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write_zsreg(channel, R0, RES_EXT_INT);
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/* Rewrite R3/R5, this time without enables masked. */
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write_zsreg(channel, R3, regs[R3]);
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write_zsreg(channel, R5, regs[R5]);
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/* Rewrite R1, this time without IRQ enabled masked. */
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write_zsreg(channel, R1, regs[R1]);
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}
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/* Reprogram the Zilog channel HW registers with the copies found in the
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* software state struct. If the transmitter is busy, we defer this update
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* until the next TX complete interrupt. Else, we do it right now.
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*
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* The UART port lock must be held and local interrupts disabled.
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*/
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static void ip22zilog_maybe_update_regs(struct uart_ip22zilog_port *up,
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struct zilog_channel *channel)
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{
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if (!ZS_REGS_HELD(up)) {
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if (ZS_TX_ACTIVE(up)) {
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up->flags |= IP22ZILOG_FLAG_REGS_HELD;
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} else {
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__load_zsregs(channel, up->curregs);
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}
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}
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}
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2007-11-29 08:21:44 +08:00
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#define Rx_BRK 0x0100 /* BREAK event software flag. */
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#define Rx_SYS 0x0200 /* SysRq event software flag. */
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static struct tty_struct *ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
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struct zilog_channel *channel)
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2005-04-17 06:20:36 +08:00
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{
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2007-11-29 08:21:44 +08:00
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struct tty_struct *tty;
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unsigned char ch, flag;
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unsigned int r1;
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2005-04-17 06:20:36 +08:00
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2007-11-29 08:21:44 +08:00
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tty = NULL;
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if (up->port.info != NULL &&
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2008-07-17 04:54:42 +08:00
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up->port.info->port.tty != NULL)
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tty = up->port.info->port.tty;
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2007-11-29 08:21:44 +08:00
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for (;;) {
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ch = readb(&channel->control);
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ZSDELAY();
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if (!(ch & Rx_CH_AV))
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break;
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2005-04-17 06:20:36 +08:00
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r1 = read_zsreg(channel, R1);
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if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
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writeb(ERR_RES, &channel->control);
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ZSDELAY();
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ZS_WSYNC(channel);
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}
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ch = readb(&channel->data);
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ZSDELAY();
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ch &= up->parity_mask;
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2007-11-29 08:21:44 +08:00
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/* Handle the null char got when BREAK is removed. */
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if (!ch)
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r1 |= up->tty_break;
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2005-04-17 06:20:36 +08:00
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/* A real serial line, record the character and status. */
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[PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
|
|
|
flag = TTY_NORMAL;
|
2005-04-17 06:20:36 +08:00
|
|
|
up->port.icount.rx++;
|
2007-11-29 08:21:44 +08:00
|
|
|
if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | Rx_SYS | Rx_BRK)) {
|
|
|
|
|
up->tty_break = 0;
|
|
|
|
|
|
|
|
|
|
if (r1 & (Rx_SYS | Rx_BRK)) {
|
2005-04-17 06:20:36 +08:00
|
|
|
up->port.icount.brk++;
|
2007-11-29 08:21:44 +08:00
|
|
|
if (r1 & Rx_SYS)
|
|
|
|
|
continue;
|
|
|
|
|
r1 &= ~(PAR_ERR | CRC_ERR);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
else if (r1 & PAR_ERR)
|
|
|
|
|
up->port.icount.parity++;
|
|
|
|
|
else if (r1 & CRC_ERR)
|
|
|
|
|
up->port.icount.frame++;
|
|
|
|
|
if (r1 & Rx_OVR)
|
|
|
|
|
up->port.icount.overrun++;
|
|
|
|
|
r1 &= up->port.read_status_mask;
|
2007-11-29 08:21:44 +08:00
|
|
|
if (r1 & Rx_BRK)
|
[PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
|
|
|
flag = TTY_BREAK;
|
2005-04-17 06:20:36 +08:00
|
|
|
else if (r1 & PAR_ERR)
|
[PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
|
|
|
flag = TTY_PARITY;
|
2005-04-17 06:20:36 +08:00
|
|
|
else if (r1 & CRC_ERR)
|
[PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
|
|
|
flag = TTY_FRAME;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (uart_handle_sysrq_char(&up->port, ch))
|
|
|
|
|
continue;
|
[PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.
This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.
When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.
For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).
Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.
The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.
I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.
Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real. That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.
Description:
tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification]. It
does now also return the number of chars inserted
There are also
tty_buffer_request_room(tty, len)
which asks for a buffer block of the length requested and returns the space
found. This improves efficiency with hardware that knows how much to
transfer.
and tty_insert_flip_string_flags(tty, str, flags, len)
to insert a string of characters and flags
For a smart interface the usual code is
len = tty_request_buffer_room(tty, amount_hardware_says);
tty_insert_flip_string(tty, buffer_from_card, len);
More description!
At the moment tty buffers are attached directly to the tty. This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)
I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers. This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.
So far so good. Lots of drivers reference tty->flip.*. Several of them also
call directly and unsafely into function pointers it provides. This will all
break. Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.
At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say
int tty_buffer_request_room(tty, size)
Try and ensure at least size bytes are available, returns actual room (may be
zero). At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative. (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space. The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.
int tty_insert_flip_char(tty, ch, flag)
As before insert a character if there is room. Now returns 1 for success, 0
for failure.
int tty_insert_flip_string(tty, str, len)
Insert a block of non error characters. Returns the number inserted.
int tty_prepare_flip_string(tty, strptr, len)
Adjust the buffer to allow len characters to be added. Returns a buffer
pointer in strptr and the length available. This allows for hardware that
needs to use functions like insl or mencpy_fromio.
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (tty)
|
|
|
|
|
uart_insert_char(&up->port, r1, Rx_OVR, ch, flag);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2007-11-29 08:21:44 +08:00
|
|
|
return tty;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void ip22zilog_status_handle(struct uart_ip22zilog_port *up,
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
|
|
|
struct zilog_channel *channel)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
unsigned char status;
|
|
|
|
|
|
|
|
|
|
status = readb(&channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
|
|
|
|
|
writeb(RES_EXT_INT, &channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (up->curregs[R15] & BRKIE) {
|
|
|
|
|
if ((status & BRK_ABRT) && !(up->prev_status & BRK_ABRT)) {
|
|
|
|
|
if (uart_handle_break(&up->port))
|
|
|
|
|
up->tty_break = Rx_SYS;
|
|
|
|
|
else
|
|
|
|
|
up->tty_break = Rx_BRK;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
if (ZS_WANTS_MODEM_STATUS(up)) {
|
|
|
|
|
if (status & SYNC)
|
|
|
|
|
up->port.icount.dsr++;
|
|
|
|
|
|
|
|
|
|
/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
|
|
|
|
|
* But it does not tell us which bit has changed, we have to keep
|
|
|
|
|
* track of this ourselves.
|
|
|
|
|
*/
|
2007-11-29 08:21:44 +08:00
|
|
|
if ((status ^ up->prev_status) ^ DCD)
|
2005-04-17 06:20:36 +08:00
|
|
|
uart_handle_dcd_change(&up->port,
|
|
|
|
|
(status & DCD));
|
2007-11-29 08:21:44 +08:00
|
|
|
if ((status ^ up->prev_status) ^ CTS)
|
2005-04-17 06:20:36 +08:00
|
|
|
uart_handle_cts_change(&up->port,
|
|
|
|
|
(status & CTS));
|
|
|
|
|
|
|
|
|
|
wake_up_interruptible(&up->port.info->delta_msr_wait);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
up->prev_status = status;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void ip22zilog_transmit_chars(struct uart_ip22zilog_port *up,
|
|
|
|
|
struct zilog_channel *channel)
|
|
|
|
|
{
|
|
|
|
|
struct circ_buf *xmit;
|
|
|
|
|
|
|
|
|
|
if (ZS_IS_CONS(up)) {
|
|
|
|
|
unsigned char status = readb(&channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
|
|
|
|
|
/* TX still busy? Just wait for the next TX done interrupt.
|
|
|
|
|
*
|
|
|
|
|
* It can occur because of how we do serial console writes. It would
|
|
|
|
|
* be nice to transmit console writes just like we normally would for
|
|
|
|
|
* a TTY line. (ie. buffered and TX interrupt driven). That is not
|
|
|
|
|
* easy because console writes cannot sleep. One solution might be
|
|
|
|
|
* to poll on enough port->xmit space becomming free. -DaveM
|
|
|
|
|
*/
|
|
|
|
|
if (!(status & Tx_BUF_EMP))
|
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
up->flags &= ~IP22ZILOG_FLAG_TX_ACTIVE;
|
|
|
|
|
|
|
|
|
|
if (ZS_REGS_HELD(up)) {
|
|
|
|
|
__load_zsregs(channel, up->curregs);
|
|
|
|
|
up->flags &= ~IP22ZILOG_FLAG_REGS_HELD;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (ZS_TX_STOPPED(up)) {
|
|
|
|
|
up->flags &= ~IP22ZILOG_FLAG_TX_STOPPED;
|
|
|
|
|
goto ack_tx_int;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (up->port.x_char) {
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_TX_ACTIVE;
|
|
|
|
|
writeb(up->port.x_char, &channel->data);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
up->port.icount.tx++;
|
|
|
|
|
up->port.x_char = 0;
|
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (up->port.info == NULL)
|
|
|
|
|
goto ack_tx_int;
|
|
|
|
|
xmit = &up->port.info->xmit;
|
2006-03-08 05:04:59 +08:00
|
|
|
if (uart_circ_empty(xmit))
|
2005-04-17 06:20:36 +08:00
|
|
|
goto ack_tx_int;
|
|
|
|
|
if (uart_tx_stopped(&up->port))
|
|
|
|
|
goto ack_tx_int;
|
|
|
|
|
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_TX_ACTIVE;
|
|
|
|
|
writeb(xmit->buf[xmit->tail], &channel->data);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
|
|
|
|
|
up->port.icount.tx++;
|
|
|
|
|
|
|
|
|
|
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
|
|
|
|
|
uart_write_wakeup(&up->port);
|
|
|
|
|
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
ack_tx_int:
|
|
|
|
|
writeb(RES_Tx_P, &channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
}
|
|
|
|
|
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
|
|
|
static irqreturn_t ip22zilog_interrupt(int irq, void *dev_id)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = dev_id;
|
|
|
|
|
|
|
|
|
|
while (up) {
|
|
|
|
|
struct zilog_channel *channel
|
|
|
|
|
= ZILOG_CHANNEL_FROM_PORT(&up->port);
|
2007-11-29 08:21:44 +08:00
|
|
|
struct tty_struct *tty;
|
2005-04-17 06:20:36 +08:00
|
|
|
unsigned char r3;
|
|
|
|
|
|
|
|
|
|
spin_lock(&up->port.lock);
|
|
|
|
|
r3 = read_zsreg(channel, R3);
|
|
|
|
|
|
|
|
|
|
/* Channel A */
|
2007-11-29 08:21:44 +08:00
|
|
|
tty = NULL;
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
|
|
|
|
|
writeb(RES_H_IUS, &channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
if (r3 & CHARxIP)
|
2007-11-29 08:21:44 +08:00
|
|
|
tty = ip22zilog_receive_chars(up, channel);
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & CHAEXT)
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
|
|
|
ip22zilog_status_handle(up, channel);
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & CHATxIP)
|
|
|
|
|
ip22zilog_transmit_chars(up, channel);
|
|
|
|
|
}
|
|
|
|
|
spin_unlock(&up->port.lock);
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (tty)
|
|
|
|
|
tty_flip_buffer_push(tty);
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/* Channel B */
|
|
|
|
|
up = up->next;
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
|
|
|
|
|
|
|
|
|
|
spin_lock(&up->port.lock);
|
2007-11-29 08:21:44 +08:00
|
|
|
tty = NULL;
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
|
|
|
|
|
writeb(RES_H_IUS, &channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
if (r3 & CHBRxIP)
|
2007-11-29 08:21:44 +08:00
|
|
|
tty = ip22zilog_receive_chars(up, channel);
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & CHBEXT)
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
|
|
|
ip22zilog_status_handle(up, channel);
|
2005-04-17 06:20:36 +08:00
|
|
|
if (r3 & CHBTxIP)
|
|
|
|
|
ip22zilog_transmit_chars(up, channel);
|
|
|
|
|
}
|
|
|
|
|
spin_unlock(&up->port.lock);
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (tty)
|
|
|
|
|
tty_flip_buffer_push(tty);
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
up = up->next;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return IRQ_HANDLED;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* A convenient way to quickly get R0 status. The caller must _not_ hold the
|
|
|
|
|
* port lock, it is acquired here.
|
|
|
|
|
*/
|
|
|
|
|
static __inline__ unsigned char ip22zilog_read_channel_status(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
struct zilog_channel *channel;
|
|
|
|
|
unsigned char status;
|
|
|
|
|
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
status = readb(&channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
|
|
|
|
|
return status;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is not held. */
|
|
|
|
|
static unsigned int ip22zilog_tx_empty(struct uart_port *port)
|
|
|
|
|
{
|
2005-06-29 16:42:38 +08:00
|
|
|
unsigned long flags;
|
2005-04-17 06:20:36 +08:00
|
|
|
unsigned char status;
|
|
|
|
|
unsigned int ret;
|
|
|
|
|
|
2005-06-29 16:42:38 +08:00
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
status = ip22zilog_read_channel_status(port);
|
2005-06-29 16:42:38 +08:00
|
|
|
|
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
if (status & Tx_BUF_EMP)
|
|
|
|
|
ret = TIOCSER_TEMT;
|
|
|
|
|
else
|
|
|
|
|
ret = 0;
|
|
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
|
}
|
|
|
|
|
|
2005-06-29 16:42:38 +08:00
|
|
|
/* The port lock is held and interrupts are disabled. */
|
2005-04-17 06:20:36 +08:00
|
|
|
static unsigned int ip22zilog_get_mctrl(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
unsigned char status;
|
|
|
|
|
unsigned int ret;
|
|
|
|
|
|
|
|
|
|
status = ip22zilog_read_channel_status(port);
|
|
|
|
|
|
|
|
|
|
ret = 0;
|
|
|
|
|
if (status & DCD)
|
|
|
|
|
ret |= TIOCM_CAR;
|
|
|
|
|
if (status & SYNC)
|
|
|
|
|
ret |= TIOCM_DSR;
|
|
|
|
|
if (status & CTS)
|
|
|
|
|
ret |= TIOCM_CTS;
|
|
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is held and interrupts are disabled. */
|
|
|
|
|
static void ip22zilog_set_mctrl(struct uart_port *port, unsigned int mctrl)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
unsigned char set_bits, clear_bits;
|
|
|
|
|
|
|
|
|
|
set_bits = clear_bits = 0;
|
|
|
|
|
|
|
|
|
|
if (mctrl & TIOCM_RTS)
|
|
|
|
|
set_bits |= RTS;
|
|
|
|
|
else
|
|
|
|
|
clear_bits |= RTS;
|
|
|
|
|
if (mctrl & TIOCM_DTR)
|
|
|
|
|
set_bits |= DTR;
|
|
|
|
|
else
|
|
|
|
|
clear_bits |= DTR;
|
|
|
|
|
|
2006-02-09 05:43:03 +08:00
|
|
|
/* NOTE: Not subject to 'transmitter active' rule. */
|
2005-04-17 06:20:36 +08:00
|
|
|
up->curregs[R5] |= set_bits;
|
|
|
|
|
up->curregs[R5] &= ~clear_bits;
|
|
|
|
|
write_zsreg(channel, R5, up->curregs[R5]);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is held and interrupts are disabled. */
|
2005-08-31 17:12:14 +08:00
|
|
|
static void ip22zilog_stop_tx(struct uart_port *port)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_TX_STOPPED;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is held and interrupts are disabled. */
|
2005-08-31 17:12:14 +08:00
|
|
|
static void ip22zilog_start_tx(struct uart_port *port)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
unsigned char status;
|
|
|
|
|
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_TX_ACTIVE;
|
|
|
|
|
up->flags &= ~IP22ZILOG_FLAG_TX_STOPPED;
|
|
|
|
|
|
|
|
|
|
status = readb(&channel->control);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
|
|
|
|
|
/* TX busy? Just wait for the TX done interrupt. */
|
|
|
|
|
if (!(status & Tx_BUF_EMP))
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
/* Send the first character to jump-start the TX done
|
|
|
|
|
* IRQ sending engine.
|
|
|
|
|
*/
|
|
|
|
|
if (port->x_char) {
|
|
|
|
|
writeb(port->x_char, &channel->data);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
port->icount.tx++;
|
|
|
|
|
port->x_char = 0;
|
|
|
|
|
} else {
|
|
|
|
|
struct circ_buf *xmit = &port->info->xmit;
|
|
|
|
|
|
|
|
|
|
writeb(xmit->buf[xmit->tail], &channel->data);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
|
|
|
|
|
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
|
|
|
|
|
port->icount.tx++;
|
|
|
|
|
|
|
|
|
|
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
|
|
|
|
|
uart_write_wakeup(&up->port);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is held and interrupts are disabled. */
|
|
|
|
|
static void ip22zilog_stop_rx(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = UART_ZILOG(port);
|
|
|
|
|
struct zilog_channel *channel;
|
|
|
|
|
|
|
|
|
|
if (ZS_IS_CONS(up))
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
|
|
|
|
|
/* Disable all RX interrupts. */
|
|
|
|
|
up->curregs[R1] &= ~RxINT_MASK;
|
|
|
|
|
ip22zilog_maybe_update_regs(up, channel);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is held. */
|
|
|
|
|
static void ip22zilog_enable_ms(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
unsigned char new_reg;
|
|
|
|
|
|
|
|
|
|
new_reg = up->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
|
|
|
|
|
if (new_reg != up->curregs[R15]) {
|
|
|
|
|
up->curregs[R15] = new_reg;
|
|
|
|
|
|
2006-02-09 05:43:03 +08:00
|
|
|
/* NOTE: Not subject to 'transmitter active' rule. */
|
2005-04-17 06:20:36 +08:00
|
|
|
write_zsreg(channel, R15, up->curregs[R15]);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is not held. */
|
|
|
|
|
static void ip22zilog_break_ctl(struct uart_port *port, int break_state)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
unsigned char set_bits, clear_bits, new_reg;
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
set_bits = clear_bits = 0;
|
|
|
|
|
|
|
|
|
|
if (break_state)
|
|
|
|
|
set_bits |= SND_BRK;
|
|
|
|
|
else
|
|
|
|
|
clear_bits |= SND_BRK;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
|
|
|
|
|
|
new_reg = (up->curregs[R5] | set_bits) & ~clear_bits;
|
|
|
|
|
if (new_reg != up->curregs[R5]) {
|
|
|
|
|
up->curregs[R5] = new_reg;
|
|
|
|
|
|
2006-02-09 05:43:03 +08:00
|
|
|
/* NOTE: Not subject to 'transmitter active' rule. */
|
2005-04-17 06:20:36 +08:00
|
|
|
write_zsreg(channel, R5, up->curregs[R5]);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
static void __ip22zilog_reset(struct uart_ip22zilog_port *up)
|
|
|
|
|
{
|
|
|
|
|
struct zilog_channel *channel;
|
|
|
|
|
int i;
|
|
|
|
|
|
|
|
|
|
if (up->flags & IP22ZILOG_FLAG_RESET_DONE)
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
/* Let pending transmits finish. */
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
|
|
|
|
|
for (i = 0; i < 1000; i++) {
|
|
|
|
|
unsigned char stat = read_zsreg(channel, R1);
|
|
|
|
|
if (stat & ALL_SNT)
|
|
|
|
|
break;
|
|
|
|
|
udelay(100);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (!ZS_IS_CHANNEL_A(up)) {
|
|
|
|
|
up++;
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
|
|
|
|
|
}
|
|
|
|
|
write_zsreg(channel, R9, FHWRES);
|
|
|
|
|
ZSDELAY_LONG();
|
|
|
|
|
(void) read_zsreg(channel, R0);
|
|
|
|
|
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_RESET_DONE;
|
|
|
|
|
up->next->flags |= IP22ZILOG_FLAG_RESET_DONE;
|
|
|
|
|
}
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
static void __ip22zilog_startup(struct uart_ip22zilog_port *up)
|
|
|
|
|
{
|
|
|
|
|
struct zilog_channel *channel;
|
|
|
|
|
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
|
2007-11-29 08:21:44 +08:00
|
|
|
|
|
|
|
|
__ip22zilog_reset(up);
|
|
|
|
|
|
|
|
|
|
__load_zsregs(channel, up->curregs);
|
|
|
|
|
/* set master interrupt enable */
|
|
|
|
|
write_zsreg(channel, R9, up->curregs[R9]);
|
2005-04-17 06:20:36 +08:00
|
|
|
up->prev_status = readb(&channel->control);
|
|
|
|
|
|
|
|
|
|
/* Enable receiver and transmitter. */
|
|
|
|
|
up->curregs[R3] |= RxENAB;
|
|
|
|
|
up->curregs[R5] |= TxENAB;
|
|
|
|
|
|
|
|
|
|
up->curregs[R1] |= EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
|
|
|
|
|
ip22zilog_maybe_update_regs(up, channel);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int ip22zilog_startup(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = UART_ZILOG(port);
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
if (ZS_IS_CONS(up))
|
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
|
__ip22zilog_startup(up);
|
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* The test for ZS_IS_CONS is explained by the following e-mail:
|
|
|
|
|
*****
|
|
|
|
|
* From: Russell King <rmk@arm.linux.org.uk>
|
|
|
|
|
* Date: Sun, 8 Dec 2002 10:18:38 +0000
|
|
|
|
|
*
|
|
|
|
|
* On Sun, Dec 08, 2002 at 02:43:36AM -0500, Pete Zaitcev wrote:
|
|
|
|
|
* > I boot my 2.5 boxes using "console=ttyS0,9600" argument,
|
|
|
|
|
* > and I noticed that something is not right with reference
|
|
|
|
|
* > counting in this case. It seems that when the console
|
|
|
|
|
* > is open by kernel initially, this is not accounted
|
|
|
|
|
* > as an open, and uart_startup is not called.
|
|
|
|
|
*
|
|
|
|
|
* That is correct. We are unable to call uart_startup when the serial
|
|
|
|
|
* console is initialised because it may need to allocate memory (as
|
|
|
|
|
* request_irq does) and the memory allocators may not have been
|
|
|
|
|
* initialised.
|
|
|
|
|
*
|
|
|
|
|
* 1. initialise the port into a state where it can send characters in the
|
|
|
|
|
* console write method.
|
|
|
|
|
*
|
|
|
|
|
* 2. don't do the actual hardware shutdown in your shutdown() method (but
|
|
|
|
|
* do the normal software shutdown - ie, free irqs etc)
|
|
|
|
|
*****
|
|
|
|
|
*/
|
|
|
|
|
static void ip22zilog_shutdown(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = UART_ZILOG(port);
|
|
|
|
|
struct zilog_channel *channel;
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
if (ZS_IS_CONS(up))
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
|
|
|
|
|
|
channel = ZILOG_CHANNEL_FROM_PORT(port);
|
|
|
|
|
|
|
|
|
|
/* Disable receiver and transmitter. */
|
|
|
|
|
up->curregs[R3] &= ~RxENAB;
|
|
|
|
|
up->curregs[R5] &= ~TxENAB;
|
|
|
|
|
|
|
|
|
|
/* Disable all interrupts and BRK assertion. */
|
|
|
|
|
up->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
|
|
|
|
|
up->curregs[R5] &= ~SND_BRK;
|
|
|
|
|
ip22zilog_maybe_update_regs(up, channel);
|
|
|
|
|
|
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Shared by TTY driver and serial console setup. The port lock is held
|
|
|
|
|
* and local interrupts are disabled.
|
|
|
|
|
*/
|
|
|
|
|
static void
|
|
|
|
|
ip22zilog_convert_to_zs(struct uart_ip22zilog_port *up, unsigned int cflag,
|
|
|
|
|
unsigned int iflag, int brg)
|
|
|
|
|
{
|
|
|
|
|
|
|
|
|
|
up->curregs[R10] = NRZ;
|
|
|
|
|
up->curregs[R11] = TCBR | RCBR;
|
|
|
|
|
|
|
|
|
|
/* Program BAUD and clock source. */
|
|
|
|
|
up->curregs[R4] &= ~XCLK_MASK;
|
|
|
|
|
up->curregs[R4] |= X16CLK;
|
|
|
|
|
up->curregs[R12] = brg & 0xff;
|
|
|
|
|
up->curregs[R13] = (brg >> 8) & 0xff;
|
|
|
|
|
up->curregs[R14] = BRENAB;
|
|
|
|
|
|
|
|
|
|
/* Character size, stop bits, and parity. */
|
|
|
|
|
up->curregs[3] &= ~RxN_MASK;
|
|
|
|
|
up->curregs[5] &= ~TxN_MASK;
|
|
|
|
|
switch (cflag & CSIZE) {
|
|
|
|
|
case CS5:
|
|
|
|
|
up->curregs[3] |= Rx5;
|
|
|
|
|
up->curregs[5] |= Tx5;
|
|
|
|
|
up->parity_mask = 0x1f;
|
|
|
|
|
break;
|
|
|
|
|
case CS6:
|
|
|
|
|
up->curregs[3] |= Rx6;
|
|
|
|
|
up->curregs[5] |= Tx6;
|
|
|
|
|
up->parity_mask = 0x3f;
|
|
|
|
|
break;
|
|
|
|
|
case CS7:
|
|
|
|
|
up->curregs[3] |= Rx7;
|
|
|
|
|
up->curregs[5] |= Tx7;
|
|
|
|
|
up->parity_mask = 0x7f;
|
|
|
|
|
break;
|
|
|
|
|
case CS8:
|
|
|
|
|
default:
|
|
|
|
|
up->curregs[3] |= Rx8;
|
|
|
|
|
up->curregs[5] |= Tx8;
|
|
|
|
|
up->parity_mask = 0xff;
|
|
|
|
|
break;
|
|
|
|
|
};
|
|
|
|
|
up->curregs[4] &= ~0x0c;
|
|
|
|
|
if (cflag & CSTOPB)
|
|
|
|
|
up->curregs[4] |= SB2;
|
|
|
|
|
else
|
|
|
|
|
up->curregs[4] |= SB1;
|
|
|
|
|
if (cflag & PARENB)
|
|
|
|
|
up->curregs[4] |= PAR_ENAB;
|
|
|
|
|
else
|
|
|
|
|
up->curregs[4] &= ~PAR_ENAB;
|
|
|
|
|
if (!(cflag & PARODD))
|
|
|
|
|
up->curregs[4] |= PAR_EVEN;
|
|
|
|
|
else
|
|
|
|
|
up->curregs[4] &= ~PAR_EVEN;
|
|
|
|
|
|
|
|
|
|
up->port.read_status_mask = Rx_OVR;
|
|
|
|
|
if (iflag & INPCK)
|
|
|
|
|
up->port.read_status_mask |= CRC_ERR | PAR_ERR;
|
|
|
|
|
if (iflag & (BRKINT | PARMRK))
|
|
|
|
|
up->port.read_status_mask |= BRK_ABRT;
|
|
|
|
|
|
|
|
|
|
up->port.ignore_status_mask = 0;
|
|
|
|
|
if (iflag & IGNPAR)
|
|
|
|
|
up->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
|
|
|
|
|
if (iflag & IGNBRK) {
|
|
|
|
|
up->port.ignore_status_mask |= BRK_ABRT;
|
|
|
|
|
if (iflag & IGNPAR)
|
|
|
|
|
up->port.ignore_status_mask |= Rx_OVR;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if ((cflag & CREAD) == 0)
|
|
|
|
|
up->port.ignore_status_mask = 0xff;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* The port lock is not held. */
|
|
|
|
|
static void
|
2006-12-08 18:38:45 +08:00
|
|
|
ip22zilog_set_termios(struct uart_port *port, struct ktermios *termios,
|
|
|
|
|
struct ktermios *old)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = (struct uart_ip22zilog_port *) port;
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
int baud, brg;
|
|
|
|
|
|
|
|
|
|
baud = uart_get_baud_rate(port, termios, old, 1200, 76800);
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
|
|
|
|
|
|
|
|
brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
|
|
|
|
|
|
|
|
|
|
ip22zilog_convert_to_zs(up, termios->c_cflag, termios->c_iflag, brg);
|
|
|
|
|
|
|
|
|
|
if (UART_ENABLE_MS(&up->port, termios->c_cflag))
|
|
|
|
|
up->flags |= IP22ZILOG_FLAG_MODEM_STATUS;
|
|
|
|
|
else
|
|
|
|
|
up->flags &= ~IP22ZILOG_FLAG_MODEM_STATUS;
|
|
|
|
|
|
|
|
|
|
ip22zilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(port));
|
2007-07-16 14:39:59 +08:00
|
|
|
uart_update_timeout(port, termios->c_cflag, baud);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static const char *ip22zilog_type(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
return "IP22-Zilog";
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* We do not request/release mappings of the registers here, this
|
|
|
|
|
* happens at early serial probe time.
|
|
|
|
|
*/
|
|
|
|
|
static void ip22zilog_release_port(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int ip22zilog_request_port(struct uart_port *port)
|
|
|
|
|
{
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* These do not need to do anything interesting either. */
|
|
|
|
|
static void ip22zilog_config_port(struct uart_port *port, int flags)
|
|
|
|
|
{
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* We do not support letting the user mess with the divisor, IRQ, etc. */
|
|
|
|
|
static int ip22zilog_verify_port(struct uart_port *port, struct serial_struct *ser)
|
|
|
|
|
{
|
|
|
|
|
return -EINVAL;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static struct uart_ops ip22zilog_pops = {
|
|
|
|
|
.tx_empty = ip22zilog_tx_empty,
|
|
|
|
|
.set_mctrl = ip22zilog_set_mctrl,
|
|
|
|
|
.get_mctrl = ip22zilog_get_mctrl,
|
|
|
|
|
.stop_tx = ip22zilog_stop_tx,
|
|
|
|
|
.start_tx = ip22zilog_start_tx,
|
|
|
|
|
.stop_rx = ip22zilog_stop_rx,
|
|
|
|
|
.enable_ms = ip22zilog_enable_ms,
|
|
|
|
|
.break_ctl = ip22zilog_break_ctl,
|
|
|
|
|
.startup = ip22zilog_startup,
|
|
|
|
|
.shutdown = ip22zilog_shutdown,
|
|
|
|
|
.set_termios = ip22zilog_set_termios,
|
|
|
|
|
.type = ip22zilog_type,
|
|
|
|
|
.release_port = ip22zilog_release_port,
|
|
|
|
|
.request_port = ip22zilog_request_port,
|
|
|
|
|
.config_port = ip22zilog_config_port,
|
|
|
|
|
.verify_port = ip22zilog_verify_port,
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
static struct uart_ip22zilog_port *ip22zilog_port_table;
|
|
|
|
|
static struct zilog_layout **ip22zilog_chip_regs;
|
|
|
|
|
|
|
|
|
|
static struct uart_ip22zilog_port *ip22zilog_irq_chain;
|
|
|
|
|
static int zilog_irq = -1;
|
|
|
|
|
|
|
|
|
|
static void * __init alloc_one_table(unsigned long size)
|
|
|
|
|
{
|
2007-02-14 16:33:07 +08:00
|
|
|
return kzalloc(size, GFP_KERNEL);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void __init ip22zilog_alloc_tables(void)
|
|
|
|
|
{
|
|
|
|
|
ip22zilog_port_table = (struct uart_ip22zilog_port *)
|
|
|
|
|
alloc_one_table(NUM_CHANNELS * sizeof(struct uart_ip22zilog_port));
|
|
|
|
|
ip22zilog_chip_regs = (struct zilog_layout **)
|
|
|
|
|
alloc_one_table(NUM_IP22ZILOG * sizeof(struct zilog_layout *));
|
|
|
|
|
|
|
|
|
|
if (ip22zilog_port_table == NULL || ip22zilog_chip_regs == NULL) {
|
|
|
|
|
panic("IP22-Zilog: Cannot allocate IP22-Zilog tables.");
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Get the address of the registers for IP22-Zilog instance CHIP. */
|
|
|
|
|
static struct zilog_layout * __init get_zs(int chip)
|
|
|
|
|
{
|
|
|
|
|
unsigned long base;
|
|
|
|
|
|
|
|
|
|
if (chip < 0 || chip >= NUM_IP22ZILOG) {
|
|
|
|
|
panic("IP22-Zilog: Illegal chip number %d in get_zs.", chip);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Not probe-able, hard code it. */
|
|
|
|
|
base = (unsigned long) &sgioc->uart;
|
|
|
|
|
|
|
|
|
|
zilog_irq = SGI_SERIAL_IRQ;
|
|
|
|
|
request_mem_region(base, 8, "IP22-Zilog");
|
|
|
|
|
|
|
|
|
|
return (struct zilog_layout *) base;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#define ZS_PUT_CHAR_MAX_DELAY 2000 /* 10 ms */
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_SERIAL_IP22_ZILOG_CONSOLE
|
2006-03-21 04:00:09 +08:00
|
|
|
static void ip22zilog_put_char(struct uart_port *port, int ch)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2006-03-21 04:00:09 +08:00
|
|
|
struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
|
2005-04-17 06:20:36 +08:00
|
|
|
int loops = ZS_PUT_CHAR_MAX_DELAY;
|
|
|
|
|
|
|
|
|
|
/* This is a timed polling loop so do not switch the explicit
|
|
|
|
|
* udelay with ZSDELAY as that is a NOP on some platforms. -DaveM
|
|
|
|
|
*/
|
|
|
|
|
do {
|
|
|
|
|
unsigned char val = readb(&channel->control);
|
|
|
|
|
if (val & Tx_BUF_EMP) {
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
udelay(5);
|
|
|
|
|
} while (--loops);
|
|
|
|
|
|
|
|
|
|
writeb(ch, &channel->data);
|
|
|
|
|
ZSDELAY();
|
|
|
|
|
ZS_WSYNC(channel);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void
|
|
|
|
|
ip22zilog_console_write(struct console *con, const char *s, unsigned int count)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = &ip22zilog_port_table[con->index];
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
2006-03-21 04:00:09 +08:00
|
|
|
uart_console_write(&up->port, s, count, ip22zilog_put_char);
|
2005-04-17 06:20:36 +08:00
|
|
|
udelay(2);
|
|
|
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int __init ip22zilog_console_setup(struct console *con, char *options)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up = &ip22zilog_port_table[con->index];
|
|
|
|
|
unsigned long flags;
|
2007-11-29 08:21:44 +08:00
|
|
|
int baud = 9600, bits = 8;
|
|
|
|
|
int parity = 'n';
|
|
|
|
|
int flow = 'n';
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
up->flags |= IP22ZILOG_FLAG_IS_CONS;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
printk(KERN_INFO "Console: ttyS%d (IP22-Zilog)\n", con->index);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
up->curregs[R15] |= BRKIE;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
__ip22zilog_startup(up);
|
|
|
|
|
|
|
|
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
|
|
2007-11-29 08:21:44 +08:00
|
|
|
if (options)
|
|
|
|
|
uart_parse_options(options, &baud, &parity, &bits, &flow);
|
|
|
|
|
return uart_set_options(&up->port, con, baud, parity, bits, flow);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static struct uart_driver ip22zilog_reg;
|
|
|
|
|
|
|
|
|
|
static struct console ip22zilog_console = {
|
|
|
|
|
.name = "ttyS",
|
|
|
|
|
.write = ip22zilog_console_write,
|
|
|
|
|
.device = uart_console_device,
|
|
|
|
|
.setup = ip22zilog_console_setup,
|
|
|
|
|
.flags = CON_PRINTBUFFER,
|
|
|
|
|
.index = -1,
|
|
|
|
|
.data = &ip22zilog_reg,
|
|
|
|
|
};
|
|
|
|
|
#endif /* CONFIG_SERIAL_IP22_ZILOG_CONSOLE */
|
|
|
|
|
|
|
|
|
|
static struct uart_driver ip22zilog_reg = {
|
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
|
.driver_name = "serial",
|
|
|
|
|
.dev_name = "ttyS",
|
|
|
|
|
.major = TTY_MAJOR,
|
|
|
|
|
.minor = 64,
|
|
|
|
|
.nr = NUM_CHANNELS,
|
|
|
|
|
#ifdef CONFIG_SERIAL_IP22_ZILOG_CONSOLE
|
|
|
|
|
.cons = &ip22zilog_console,
|
|
|
|
|
#endif
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
static void __init ip22zilog_prepare(void)
|
|
|
|
|
{
|
|
|
|
|
struct uart_ip22zilog_port *up;
|
|
|
|
|
struct zilog_layout *rp;
|
|
|
|
|
int channel, chip;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Temporary fix.
|
|
|
|
|
*/
|
|
|
|
|
for (channel = 0; channel < NUM_CHANNELS; channel++)
|
|
|
|
|
spin_lock_init(&ip22zilog_port_table[channel].port.lock);
|
|
|
|
|
|
|
|
|
|
ip22zilog_irq_chain = &ip22zilog_port_table[NUM_CHANNELS - 1];
|
|
|
|
|
up = &ip22zilog_port_table[0];
|
|
|
|
|
for (channel = NUM_CHANNELS - 1 ; channel > 0; channel--)
|
|
|
|
|
up[channel].next = &up[channel - 1];
|
|
|
|
|
up[channel].next = NULL;
|
|
|
|
|
|
|
|
|
|
for (chip = 0; chip < NUM_IP22ZILOG; chip++) {
|
|
|
|
|
if (!ip22zilog_chip_regs[chip]) {
|
|
|
|
|
ip22zilog_chip_regs[chip] = rp = get_zs(chip);
|
|
|
|
|
|
|
|
|
|
up[(chip * 2) + 0].port.membase = (char *) &rp->channelB;
|
|
|
|
|
up[(chip * 2) + 1].port.membase = (char *) &rp->channelA;
|
|
|
|
|
|
|
|
|
|
/* In theory mapbase is the physical address ... */
|
|
|
|
|
up[(chip * 2) + 0].port.mapbase =
|
|
|
|
|
(unsigned long) ioremap((unsigned long) &rp->channelB, 8);
|
|
|
|
|
up[(chip * 2) + 1].port.mapbase =
|
|
|
|
|
(unsigned long) ioremap((unsigned long) &rp->channelA, 8);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Channel A */
|
|
|
|
|
up[(chip * 2) + 0].port.iotype = UPIO_MEM;
|
|
|
|
|
up[(chip * 2) + 0].port.irq = zilog_irq;
|
|
|
|
|
up[(chip * 2) + 0].port.uartclk = ZS_CLOCK;
|
|
|
|
|
up[(chip * 2) + 0].port.fifosize = 1;
|
|
|
|
|
up[(chip * 2) + 0].port.ops = &ip22zilog_pops;
|
|
|
|
|
up[(chip * 2) + 0].port.type = PORT_IP22ZILOG;
|
|
|
|
|
up[(chip * 2) + 0].port.flags = 0;
|
|
|
|
|
up[(chip * 2) + 0].port.line = (chip * 2) + 0;
|
|
|
|
|
up[(chip * 2) + 0].flags = 0;
|
|
|
|
|
|
|
|
|
|
/* Channel B */
|
|
|
|
|
up[(chip * 2) + 1].port.iotype = UPIO_MEM;
|
|
|
|
|
up[(chip * 2) + 1].port.irq = zilog_irq;
|
|
|
|
|
up[(chip * 2) + 1].port.uartclk = ZS_CLOCK;
|
|
|
|
|
up[(chip * 2) + 1].port.fifosize = 1;
|
|
|
|
|
up[(chip * 2) + 1].port.ops = &ip22zilog_pops;
|
|
|
|
|
up[(chip * 2) + 1].port.type = PORT_IP22ZILOG;
|
|
|
|
|
up[(chip * 2) + 1].port.line = (chip * 2) + 1;
|
[SERIAL] IP22: fix serial console hangs
The patch below fixes serial console hangs as seen on IP22
machines. Typically, while booting, the machine hangs for ~1 minute
displaying "INIT: ", then the same thing happens again when init
enters in the designated runlevel and finally the getty process on
ttyS0 hangs indefinitely (though strace'ing it helps).
strace (-e raw=ioctl, otherwise the ioctl() translation is utterly
bogus) reveals that getty hangs on ioctl() 0x540f which happens to be
TCSETSW (I saw it hang on another console ioctl() but couldn't
reproduce that one).
A diff between ip22zilog and sunzilog revealed the following
differences:
1. the channel A flag being set on up.port.flags instead of up.flags
2. the channel A flag being set on what is marked as being channel B
3. sunzilog has a call to uart_update_timeout(port, termios->c_cflag, baud);
at the end of sunzilog_set_termios(), which ip22zilog lacks (on
purpose ?)
The patch below addresses point 1 and fixes the serial console hangs
just fine. However point 2 should be investigated by someone familiar
with the IP22 Zilog; it's probably OK as is but even if it is, a
comment in ip22zilog.c is badly needed.
Point 3 is left as an exercise for whoever feels like digging into
ip22zilog :)
These are the main obvious differences between ip22zilog and
sunzilog. Newer versions of sunzilog (Linus's git tree as of today)
are more close to ip22zilog as the sbus_{write,read}b have been
changed into simple {write,read}b, which shrinks the diff by a fair
amount. Resyncing both drivers should be doable in a few hours time
now for someone familiar with the IP22 Zilog hardware.
Signed-off-by: Julien BLACHE <jb@jblache.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-10 02:40:17 +08:00
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up[(chip * 2) + 1].flags |= IP22ZILOG_FLAG_IS_CHANNEL_A;
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2005-04-17 06:20:36 +08:00
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}
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2007-11-29 08:21:44 +08:00
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for (channel = 0; channel < NUM_CHANNELS; channel++) {
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struct uart_ip22zilog_port *up = &ip22zilog_port_table[channel];
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int brg;
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2005-04-17 06:20:36 +08:00
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/* Normal serial TTY. */
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up->parity_mask = 0xff;
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up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
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up->curregs[R4] = PAR_EVEN | X16CLK | SB1;
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up->curregs[R3] = RxENAB | Rx8;
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up->curregs[R5] = TxENAB | Tx8;
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up->curregs[R9] = NV | MIE;
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up->curregs[R10] = NRZ;
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up->curregs[R11] = TCBR | RCBR;
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2007-11-29 08:21:44 +08:00
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brg = BPS_TO_BRG(9600, ZS_CLOCK / ZS_CLOCK_DIVISOR);
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2005-04-17 06:20:36 +08:00
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up->curregs[R12] = (brg & 0xff);
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up->curregs[R13] = (brg >> 8) & 0xff;
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up->curregs[R14] = BRENAB;
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}
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}
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static int __init ip22zilog_ports_init(void)
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{
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int ret;
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printk(KERN_INFO "Serial: IP22 Zilog driver (%d chips).\n", NUM_IP22ZILOG);
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ip22zilog_prepare();
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if (request_irq(zilog_irq, ip22zilog_interrupt, 0,
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"IP22-Zilog", ip22zilog_irq_chain)) {
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panic("IP22-Zilog: Unable to register zs interrupt handler.\n");
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}
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ret = uart_register_driver(&ip22zilog_reg);
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if (ret == 0) {
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int i;
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for (i = 0; i < NUM_CHANNELS; i++) {
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struct uart_ip22zilog_port *up = &ip22zilog_port_table[i];
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uart_add_one_port(&ip22zilog_reg, &up->port);
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}
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}
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return ret;
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}
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static int __init ip22zilog_init(void)
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{
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/* IP22 Zilog setup is hard coded, no probing to do. */
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ip22zilog_alloc_tables();
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ip22zilog_ports_init();
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return 0;
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}
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static void __exit ip22zilog_exit(void)
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{
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int i;
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2006-10-01 14:29:22 +08:00
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struct uart_ip22zilog_port *up;
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2005-04-17 06:20:36 +08:00
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for (i = 0; i < NUM_CHANNELS; i++) {
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2006-10-01 14:29:22 +08:00
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up = &ip22zilog_port_table[i];
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2005-04-17 06:20:36 +08:00
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uart_remove_one_port(&ip22zilog_reg, &up->port);
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}
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2006-10-01 14:29:22 +08:00
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/* Free IO mem */
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up = &ip22zilog_port_table[0];
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for (i = 0; i < NUM_IP22ZILOG; i++) {
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if (up[(i * 2) + 0].port.mapbase) {
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iounmap((void*)up[(i * 2) + 0].port.mapbase);
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up[(i * 2) + 0].port.mapbase = 0;
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}
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if (up[(i * 2) + 1].port.mapbase) {
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iounmap((void*)up[(i * 2) + 1].port.mapbase);
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up[(i * 2) + 1].port.mapbase = 0;
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}
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}
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2005-04-17 06:20:36 +08:00
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uart_unregister_driver(&ip22zilog_reg);
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}
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module_init(ip22zilog_init);
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module_exit(ip22zilog_exit);
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/* David wrote it but I'm to blame for the bugs ... */
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MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");
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MODULE_DESCRIPTION("SGI Zilog serial port driver");
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MODULE_LICENSE("GPL");
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