linux-sg2042/arch/arm/mach-davinci/serial.c

158 lines
3.8 KiB
C

/*
* TI DaVinci serial driver
*
* Copyright (C) 2006 Texas Instruments.
*
* 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/serial_8250.h>
#include <linux/serial_reg.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <mach/serial.h>
#include <mach/irqs.h>
#include <mach/cputype.h>
#include "clock.h"
static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
int offset)
{
offset <<= up->regshift;
return (unsigned int)__raw_readl(IO_ADDRESS(up->mapbase) + offset);
}
static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
int value)
{
offset <<= p->regshift;
__raw_writel(value, IO_ADDRESS(p->mapbase) + offset);
}
static struct plat_serial8250_port serial_platform_data[] = {
{
.mapbase = DAVINCI_UART0_BASE,
.irq = IRQ_UARTINT0,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
UPF_IOREMAP,
.iotype = UPIO_MEM,
.regshift = 2,
},
{
.mapbase = DAVINCI_UART1_BASE,
.irq = IRQ_UARTINT1,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
UPF_IOREMAP,
.iotype = UPIO_MEM,
.regshift = 2,
},
{
.mapbase = DAVINCI_UART2_BASE,
.irq = IRQ_UARTINT2,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
UPF_IOREMAP,
.iotype = UPIO_MEM,
.regshift = 2,
},
{
.flags = 0
},
};
static struct platform_device serial_device = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = serial_platform_data,
},
};
static void __init davinci_serial_reset(struct plat_serial8250_port *p)
{
unsigned int pwremu = 0;
serial_write_reg(p, UART_IER, 0); /* disable all interrupts */
/* reset both transmitter and receiver: bits 14,13 = UTRST, URRST */
serial_write_reg(p, UART_DAVINCI_PWREMU, pwremu);
mdelay(10);
pwremu |= (0x3 << 13);
pwremu |= 0x1;
serial_write_reg(p, UART_DAVINCI_PWREMU, pwremu);
if (cpu_is_davinci_dm646x())
serial_write_reg(p, UART_DM646X_SCR,
UART_DM646X_SCR_TX_WATERMARK);
}
void __init davinci_serial_init(struct davinci_uart_config *info)
{
int i;
char name[16];
struct clk *uart_clk;
struct device *dev = &serial_device.dev;
/*
* Make sure the serial ports are muxed on at this point.
* You have to mux them off in device drivers later on
* if not needed.
*/
for (i = 0; i < DAVINCI_MAX_NR_UARTS; i++) {
struct plat_serial8250_port *p = serial_platform_data + i;
if (!(info->enabled_uarts & (1 << i))) {
p->flags = 0;
continue;
}
if (cpu_is_davinci_dm646x())
p->iotype = UPIO_MEM32;
if (cpu_is_davinci_dm355()) {
if (i == 2) {
p->mapbase = (unsigned long)DM355_UART2_BASE;
p->irq = IRQ_DM355_UARTINT2;
}
}
sprintf(name, "uart%d", i);
uart_clk = clk_get(dev, name);
if (IS_ERR(uart_clk))
printk(KERN_ERR "%s:%d: failed to get UART%d clock\n",
__func__, __LINE__, i);
else {
clk_enable(uart_clk);
p->uartclk = clk_get_rate(uart_clk);
davinci_serial_reset(p);
}
}
}
static int __init davinci_init(void)
{
return platform_device_register(&serial_device);
}
arch_initcall(davinci_init);