635 lines
15 KiB
C
635 lines
15 KiB
C
/*
|
|
** mux.c:
|
|
** serial driver for the Mux console found in some PA-RISC servers.
|
|
**
|
|
** (c) Copyright 2002 Ryan Bradetich
|
|
** (c) Copyright 2002 Hewlett-Packard Company
|
|
**
|
|
** This program is free software; you can redistribute it and/or modify
|
|
** it under the terms of the GNU General Public License as published by
|
|
** the Free Software Foundation; either version 2 of the License, or
|
|
** (at your option) any later version.
|
|
**
|
|
** This Driver currently only supports the console (port 0) on the MUX.
|
|
** Additional work will be needed on this driver to enable the full
|
|
** functionality of the MUX.
|
|
**
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/init.h>
|
|
#include <linux/serial.h>
|
|
#include <linux/tty.h>
|
|
#include <linux/tty_flip.h>
|
|
#include <linux/console.h>
|
|
#include <linux/delay.h> /* for udelay */
|
|
#include <linux/device.h>
|
|
#include <asm/io.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/parisc-device.h>
|
|
|
|
#ifdef CONFIG_MAGIC_SYSRQ
|
|
#include <linux/sysrq.h>
|
|
#define SUPPORT_SYSRQ
|
|
#endif
|
|
|
|
#include <linux/serial_core.h>
|
|
|
|
#define MUX_OFFSET 0x800
|
|
#define MUX_LINE_OFFSET 0x80
|
|
|
|
#define MUX_FIFO_SIZE 255
|
|
#define MUX_POLL_DELAY (30 * HZ / 1000)
|
|
|
|
#define IO_DATA_REG_OFFSET 0x3c
|
|
#define IO_DCOUNT_REG_OFFSET 0x40
|
|
|
|
#define MUX_EOFIFO(status) ((status & 0xF000) == 0xF000)
|
|
#define MUX_STATUS(status) ((status & 0xF000) == 0x8000)
|
|
#define MUX_BREAK(status) ((status & 0xF000) == 0x2000)
|
|
|
|
#define MUX_NR 256
|
|
static unsigned int port_cnt __read_mostly;
|
|
struct mux_port {
|
|
struct uart_port port;
|
|
int enabled;
|
|
};
|
|
static struct mux_port mux_ports[MUX_NR];
|
|
|
|
static struct uart_driver mux_driver = {
|
|
.owner = THIS_MODULE,
|
|
.driver_name = "ttyB",
|
|
.dev_name = "ttyB",
|
|
.major = MUX_MAJOR,
|
|
.minor = 0,
|
|
.nr = MUX_NR,
|
|
};
|
|
|
|
static struct timer_list mux_timer;
|
|
|
|
#define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + IO_DATA_REG_OFFSET)
|
|
#define UART_GET_FIFO_CNT(p) __raw_readl((p)->membase + IO_DCOUNT_REG_OFFSET)
|
|
|
|
/**
|
|
* get_mux_port_count - Get the number of available ports on the Mux.
|
|
* @dev: The parisc device.
|
|
*
|
|
* This function is used to determine the number of ports the Mux
|
|
* supports. The IODC data reports the number of ports the Mux
|
|
* can support, but there are cases where not all the Mux ports
|
|
* are connected. This function can override the IODC and
|
|
* return the true port count.
|
|
*/
|
|
static int __init get_mux_port_count(struct parisc_device *dev)
|
|
{
|
|
int status;
|
|
u8 iodc_data[32];
|
|
unsigned long bytecnt;
|
|
|
|
/* If this is the built-in Mux for the K-Class (Eole CAP/MUX),
|
|
* we only need to allocate resources for 1 port since the
|
|
* other 7 ports are not connected.
|
|
*/
|
|
if(dev->id.hversion == 0x15)
|
|
return 1;
|
|
|
|
status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32);
|
|
BUG_ON(status != PDC_OK);
|
|
|
|
/* Return the number of ports specified in the iodc data. */
|
|
return ((((iodc_data)[4] & 0xf0) >> 4) * 8) + 8;
|
|
}
|
|
|
|
/**
|
|
* mux_tx_empty - Check if the transmitter fifo is empty.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* This function test if the transmitter fifo for the port
|
|
* described by 'port' is empty. If it is empty, this function
|
|
* should return TIOCSER_TEMT, otherwise return 0.
|
|
*/
|
|
static unsigned int mux_tx_empty(struct uart_port *port)
|
|
{
|
|
return UART_GET_FIFO_CNT(port) ? 0 : TIOCSER_TEMT;
|
|
}
|
|
|
|
/**
|
|
* mux_set_mctrl - Set the current state of the modem control inputs.
|
|
* @ports: Ptr to the uart_port.
|
|
* @mctrl: Modem control bits.
|
|
*
|
|
* The Serial MUX does not support CTS, DCD or DSR so this function
|
|
* is ignored.
|
|
*/
|
|
static void mux_set_mctrl(struct uart_port *port, unsigned int mctrl)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_get_mctrl - Returns the current state of modem control inputs.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* The Serial MUX does not support CTS, DCD or DSR so these lines are
|
|
* treated as permanently active.
|
|
*/
|
|
static unsigned int mux_get_mctrl(struct uart_port *port)
|
|
{
|
|
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
|
|
}
|
|
|
|
/**
|
|
* mux_stop_tx - Stop transmitting characters.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* The Serial MUX does not support this function.
|
|
*/
|
|
static void mux_stop_tx(struct uart_port *port)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_start_tx - Start transmitting characters.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* The Serial Mux does not support this function.
|
|
*/
|
|
static void mux_start_tx(struct uart_port *port)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_stop_rx - Stop receiving characters.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* The Serial Mux does not support this function.
|
|
*/
|
|
static void mux_stop_rx(struct uart_port *port)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_enable_ms - Enable modum status interrupts.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* The Serial Mux does not support this function.
|
|
*/
|
|
static void mux_enable_ms(struct uart_port *port)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_break_ctl - Control the transmitssion of a break signal.
|
|
* @port: Ptr to the uart_port.
|
|
* @break_state: Raise/Lower the break signal.
|
|
*
|
|
* The Serial Mux does not support this function.
|
|
*/
|
|
static void mux_break_ctl(struct uart_port *port, int break_state)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_write - Write chars to the mux fifo.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* This function writes all the data from the uart buffer to
|
|
* the mux fifo.
|
|
*/
|
|
static void mux_write(struct uart_port *port)
|
|
{
|
|
int count;
|
|
struct circ_buf *xmit = &port->state->xmit;
|
|
|
|
if(port->x_char) {
|
|
UART_PUT_CHAR(port, port->x_char);
|
|
port->icount.tx++;
|
|
port->x_char = 0;
|
|
return;
|
|
}
|
|
|
|
if(uart_circ_empty(xmit) || uart_tx_stopped(port)) {
|
|
mux_stop_tx(port);
|
|
return;
|
|
}
|
|
|
|
count = (port->fifosize) - UART_GET_FIFO_CNT(port);
|
|
do {
|
|
UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
|
|
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
|
|
port->icount.tx++;
|
|
if(uart_circ_empty(xmit))
|
|
break;
|
|
|
|
} while(--count > 0);
|
|
|
|
while(UART_GET_FIFO_CNT(port))
|
|
udelay(1);
|
|
|
|
if(uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
|
|
uart_write_wakeup(port);
|
|
|
|
if (uart_circ_empty(xmit))
|
|
mux_stop_tx(port);
|
|
}
|
|
|
|
/**
|
|
* mux_read - Read chars from the mux fifo.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* This reads all available data from the mux's fifo and pushes
|
|
* the data to the tty layer.
|
|
*/
|
|
static void mux_read(struct uart_port *port)
|
|
{
|
|
int data;
|
|
struct tty_struct *tty = port->state->port.tty;
|
|
__u32 start_count = port->icount.rx;
|
|
|
|
while(1) {
|
|
data = __raw_readl(port->membase + IO_DATA_REG_OFFSET);
|
|
|
|
if (MUX_STATUS(data))
|
|
continue;
|
|
|
|
if (MUX_EOFIFO(data))
|
|
break;
|
|
|
|
port->icount.rx++;
|
|
|
|
if (MUX_BREAK(data)) {
|
|
port->icount.brk++;
|
|
if(uart_handle_break(port))
|
|
continue;
|
|
}
|
|
|
|
if (uart_handle_sysrq_char(port, data & 0xffu))
|
|
continue;
|
|
|
|
tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL);
|
|
}
|
|
|
|
if (start_count != port->icount.rx) {
|
|
tty_flip_buffer_push(tty);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* mux_startup - Initialize the port.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* Grab any resources needed for this port and start the
|
|
* mux timer.
|
|
*/
|
|
static int mux_startup(struct uart_port *port)
|
|
{
|
|
mux_ports[port->line].enabled = 1;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mux_shutdown - Disable the port.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* Release any resources needed for the port.
|
|
*/
|
|
static void mux_shutdown(struct uart_port *port)
|
|
{
|
|
mux_ports[port->line].enabled = 0;
|
|
}
|
|
|
|
/**
|
|
* mux_set_termios - Chane port parameters.
|
|
* @port: Ptr to the uart_port.
|
|
* @termios: new termios settings.
|
|
* @old: old termios settings.
|
|
*
|
|
* The Serial Mux does not support this function.
|
|
*/
|
|
static void
|
|
mux_set_termios(struct uart_port *port, struct ktermios *termios,
|
|
struct ktermios *old)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_type - Describe the port.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* Return a pointer to a string constant describing the
|
|
* specified port.
|
|
*/
|
|
static const char *mux_type(struct uart_port *port)
|
|
{
|
|
return "Mux";
|
|
}
|
|
|
|
/**
|
|
* mux_release_port - Release memory and IO regions.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* Release any memory and IO region resources currently in use by
|
|
* the port.
|
|
*/
|
|
static void mux_release_port(struct uart_port *port)
|
|
{
|
|
}
|
|
|
|
/**
|
|
* mux_request_port - Request memory and IO regions.
|
|
* @port: Ptr to the uart_port.
|
|
*
|
|
* Request any memory and IO region resources required by the port.
|
|
* If any fail, no resources should be registered when this function
|
|
* returns, and it should return -EBUSY on failure.
|
|
*/
|
|
static int mux_request_port(struct uart_port *port)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mux_config_port - Perform port autoconfiguration.
|
|
* @port: Ptr to the uart_port.
|
|
* @type: Bitmask of required configurations.
|
|
*
|
|
* Perform any autoconfiguration steps for the port. This function is
|
|
* called if the UPF_BOOT_AUTOCONF flag is specified for the port.
|
|
* [Note: This is required for now because of a bug in the Serial core.
|
|
* rmk has already submitted a patch to linus, should be available for
|
|
* 2.5.47.]
|
|
*/
|
|
static void mux_config_port(struct uart_port *port, int type)
|
|
{
|
|
port->type = PORT_MUX;
|
|
}
|
|
|
|
/**
|
|
* mux_verify_port - Verify the port information.
|
|
* @port: Ptr to the uart_port.
|
|
* @ser: Ptr to the serial information.
|
|
*
|
|
* Verify the new serial port information contained within serinfo is
|
|
* suitable for this port type.
|
|
*/
|
|
static int mux_verify_port(struct uart_port *port, struct serial_struct *ser)
|
|
{
|
|
if(port->membase == NULL)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mux_drv_poll - Mux poll function.
|
|
* @unused: Unused variable
|
|
*
|
|
* This function periodically polls the Serial MUX to check for new data.
|
|
*/
|
|
static void mux_poll(unsigned long unused)
|
|
{
|
|
int i;
|
|
|
|
for(i = 0; i < port_cnt; ++i) {
|
|
if(!mux_ports[i].enabled)
|
|
continue;
|
|
|
|
mux_read(&mux_ports[i].port);
|
|
mux_write(&mux_ports[i].port);
|
|
}
|
|
|
|
mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_SERIAL_MUX_CONSOLE
|
|
static void mux_console_write(struct console *co, const char *s, unsigned count)
|
|
{
|
|
/* Wait until the FIFO drains. */
|
|
while(UART_GET_FIFO_CNT(&mux_ports[0].port))
|
|
udelay(1);
|
|
|
|
while(count--) {
|
|
if(*s == '\n') {
|
|
UART_PUT_CHAR(&mux_ports[0].port, '\r');
|
|
}
|
|
UART_PUT_CHAR(&mux_ports[0].port, *s++);
|
|
}
|
|
|
|
}
|
|
|
|
static int mux_console_setup(struct console *co, char *options)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
struct tty_driver *mux_console_device(struct console *co, int *index)
|
|
{
|
|
*index = co->index;
|
|
return mux_driver.tty_driver;
|
|
}
|
|
|
|
static struct console mux_console = {
|
|
.name = "ttyB",
|
|
.write = mux_console_write,
|
|
.device = mux_console_device,
|
|
.setup = mux_console_setup,
|
|
.flags = CON_ENABLED | CON_PRINTBUFFER,
|
|
.index = 0,
|
|
};
|
|
|
|
#define MUX_CONSOLE &mux_console
|
|
#else
|
|
#define MUX_CONSOLE NULL
|
|
#endif
|
|
|
|
static struct uart_ops mux_pops = {
|
|
.tx_empty = mux_tx_empty,
|
|
.set_mctrl = mux_set_mctrl,
|
|
.get_mctrl = mux_get_mctrl,
|
|
.stop_tx = mux_stop_tx,
|
|
.start_tx = mux_start_tx,
|
|
.stop_rx = mux_stop_rx,
|
|
.enable_ms = mux_enable_ms,
|
|
.break_ctl = mux_break_ctl,
|
|
.startup = mux_startup,
|
|
.shutdown = mux_shutdown,
|
|
.set_termios = mux_set_termios,
|
|
.type = mux_type,
|
|
.release_port = mux_release_port,
|
|
.request_port = mux_request_port,
|
|
.config_port = mux_config_port,
|
|
.verify_port = mux_verify_port,
|
|
};
|
|
|
|
/**
|
|
* mux_probe - Determine if the Serial Mux should claim this device.
|
|
* @dev: The parisc device.
|
|
*
|
|
* Deterimine if the Serial Mux should claim this chip (return 0)
|
|
* or not (return 1).
|
|
*/
|
|
static int __init mux_probe(struct parisc_device *dev)
|
|
{
|
|
int i, status;
|
|
|
|
int port_count = get_mux_port_count(dev);
|
|
printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.6\n", port_count);
|
|
|
|
dev_set_drvdata(&dev->dev, (void *)(long)port_count);
|
|
request_mem_region(dev->hpa.start + MUX_OFFSET,
|
|
port_count * MUX_LINE_OFFSET, "Mux");
|
|
|
|
if(!port_cnt) {
|
|
mux_driver.cons = MUX_CONSOLE;
|
|
|
|
status = uart_register_driver(&mux_driver);
|
|
if(status) {
|
|
printk(KERN_ERR "Serial mux: Unable to register driver.\n");
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
for(i = 0; i < port_count; ++i, ++port_cnt) {
|
|
struct uart_port *port = &mux_ports[port_cnt].port;
|
|
port->iobase = 0;
|
|
port->mapbase = dev->hpa.start + MUX_OFFSET +
|
|
(i * MUX_LINE_OFFSET);
|
|
port->membase = ioremap_nocache(port->mapbase, MUX_LINE_OFFSET);
|
|
port->iotype = UPIO_MEM;
|
|
port->type = PORT_MUX;
|
|
port->irq = 0;
|
|
port->uartclk = 0;
|
|
port->fifosize = MUX_FIFO_SIZE;
|
|
port->ops = &mux_pops;
|
|
port->flags = UPF_BOOT_AUTOCONF;
|
|
port->line = port_cnt;
|
|
|
|
/* The port->timeout needs to match what is present in
|
|
* uart_wait_until_sent in serial_core.c. Otherwise
|
|
* the time spent in msleep_interruptable will be very
|
|
* long, causing the appearance of a console hang.
|
|
*/
|
|
port->timeout = HZ / 50;
|
|
spin_lock_init(&port->lock);
|
|
|
|
status = uart_add_one_port(&mux_driver, port);
|
|
BUG_ON(status);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mux_remove(struct parisc_device *dev)
|
|
{
|
|
int i, j;
|
|
int port_count = (long)dev_get_drvdata(&dev->dev);
|
|
|
|
/* Find Port 0 for this card in the mux_ports list. */
|
|
for(i = 0; i < port_cnt; ++i) {
|
|
if(mux_ports[i].port.mapbase == dev->hpa.start + MUX_OFFSET)
|
|
break;
|
|
}
|
|
BUG_ON(i + port_count > port_cnt);
|
|
|
|
/* Release the resources associated with each port on the device. */
|
|
for(j = 0; j < port_count; ++j, ++i) {
|
|
struct uart_port *port = &mux_ports[i].port;
|
|
|
|
uart_remove_one_port(&mux_driver, port);
|
|
if(port->membase)
|
|
iounmap(port->membase);
|
|
}
|
|
|
|
release_mem_region(dev->hpa.start + MUX_OFFSET, port_count * MUX_LINE_OFFSET);
|
|
return 0;
|
|
}
|
|
|
|
/* Hack. This idea was taken from the 8250_gsc.c on how to properly order
|
|
* the serial port detection in the proper order. The idea is we always
|
|
* want the builtin mux to be detected before addin mux cards, so we
|
|
* specifically probe for the builtin mux cards first.
|
|
*
|
|
* This table only contains the parisc_device_id of known builtin mux
|
|
* devices. All other mux cards will be detected by the generic mux_tbl.
|
|
*/
|
|
static struct parisc_device_id builtin_mux_tbl[] = {
|
|
{ HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x15, 0x0000D }, /* All K-class */
|
|
{ HPHW_A_DIRECT, HVERSION_REV_ANY_ID, 0x44, 0x0000D }, /* E35, E45, and E55 */
|
|
{ 0, }
|
|
};
|
|
|
|
static struct parisc_device_id mux_tbl[] = {
|
|
{ HPHW_A_DIRECT, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x0000D },
|
|
{ 0, }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(parisc, builtin_mux_tbl);
|
|
MODULE_DEVICE_TABLE(parisc, mux_tbl);
|
|
|
|
static struct parisc_driver builtin_serial_mux_driver = {
|
|
.name = "builtin_serial_mux",
|
|
.id_table = builtin_mux_tbl,
|
|
.probe = mux_probe,
|
|
.remove = mux_remove,
|
|
};
|
|
|
|
static struct parisc_driver serial_mux_driver = {
|
|
.name = "serial_mux",
|
|
.id_table = mux_tbl,
|
|
.probe = mux_probe,
|
|
.remove = mux_remove,
|
|
};
|
|
|
|
/**
|
|
* mux_init - Serial MUX initialization procedure.
|
|
*
|
|
* Register the Serial MUX driver.
|
|
*/
|
|
static int __init mux_init(void)
|
|
{
|
|
register_parisc_driver(&builtin_serial_mux_driver);
|
|
register_parisc_driver(&serial_mux_driver);
|
|
|
|
if(port_cnt > 0) {
|
|
/* Start the Mux timer */
|
|
init_timer(&mux_timer);
|
|
mux_timer.function = mux_poll;
|
|
mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
|
|
|
|
#ifdef CONFIG_SERIAL_MUX_CONSOLE
|
|
register_console(&mux_console);
|
|
#endif
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mux_exit - Serial MUX cleanup procedure.
|
|
*
|
|
* Unregister the Serial MUX driver from the tty layer.
|
|
*/
|
|
static void __exit mux_exit(void)
|
|
{
|
|
/* Delete the Mux timer. */
|
|
if(port_cnt > 0) {
|
|
del_timer(&mux_timer);
|
|
#ifdef CONFIG_SERIAL_MUX_CONSOLE
|
|
unregister_console(&mux_console);
|
|
#endif
|
|
}
|
|
|
|
unregister_parisc_driver(&builtin_serial_mux_driver);
|
|
unregister_parisc_driver(&serial_mux_driver);
|
|
uart_unregister_driver(&mux_driver);
|
|
}
|
|
|
|
module_init(mux_init);
|
|
module_exit(mux_exit);
|
|
|
|
MODULE_AUTHOR("Ryan Bradetich");
|
|
MODULE_DESCRIPTION("Serial MUX driver");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_CHARDEV_MAJOR(MUX_MAJOR);
|