mirror of https://gitee.com/openkylin/linux.git
143 lines
3.4 KiB
C
143 lines
3.4 KiB
C
/*
|
|
* AVR power-management chip interface for the Buffalo Linkstation /
|
|
* Kurobox Platform.
|
|
*
|
|
* Author: 2006 (c) G. Liakhovetski
|
|
* g.liakhovetski@gmx.de
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public License
|
|
* version 2. This program is licensed "as is" without any warranty of
|
|
* any kind, whether express or implied.
|
|
*/
|
|
#include <linux/workqueue.h>
|
|
#include <linux/string.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/serial_reg.h>
|
|
#include <linux/serial_8250.h>
|
|
#include <asm/io.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/termbits.h>
|
|
|
|
#include "mpc10x.h"
|
|
|
|
static void __iomem *avr_addr;
|
|
static unsigned long avr_clock;
|
|
|
|
static struct work_struct wd_work;
|
|
|
|
static void wd_stop(struct work_struct *unused)
|
|
{
|
|
const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK";
|
|
int i = 0, rescue = 8;
|
|
int len = strlen(string);
|
|
|
|
while (rescue--) {
|
|
int j;
|
|
char lsr = in_8(avr_addr + UART_LSR);
|
|
|
|
if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) {
|
|
for (j = 0; j < 16 && i < len; j++, i++)
|
|
out_8(avr_addr + UART_TX, string[i]);
|
|
if (i == len) {
|
|
/* Read "OK" back: 4ms for the last "KKKK"
|
|
plus a couple bytes back */
|
|
msleep(7);
|
|
printk("linkstation: disarming the AVR watchdog: ");
|
|
while (in_8(avr_addr + UART_LSR) & UART_LSR_DR)
|
|
printk("%c", in_8(avr_addr + UART_RX));
|
|
break;
|
|
}
|
|
}
|
|
msleep(17);
|
|
}
|
|
printk("\n");
|
|
}
|
|
|
|
#define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600)
|
|
|
|
void avr_uart_configure(void)
|
|
{
|
|
unsigned char cval = UART_LCR_WLEN8;
|
|
unsigned int quot = AVR_QUOT(avr_clock);
|
|
|
|
if (!avr_addr || !avr_clock)
|
|
return;
|
|
|
|
out_8(avr_addr + UART_LCR, cval); /* initialise UART */
|
|
out_8(avr_addr + UART_MCR, 0);
|
|
out_8(avr_addr + UART_IER, 0);
|
|
|
|
cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR;
|
|
|
|
out_8(avr_addr + UART_LCR, cval); /* Set character format */
|
|
|
|
out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
|
|
out_8(avr_addr + UART_DLL, quot & 0xff); /* LS of divisor */
|
|
out_8(avr_addr + UART_DLM, quot >> 8); /* MS of divisor */
|
|
out_8(avr_addr + UART_LCR, cval); /* reset DLAB */
|
|
out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
|
|
}
|
|
|
|
void avr_uart_send(const char c)
|
|
{
|
|
if (!avr_addr || !avr_clock)
|
|
return;
|
|
|
|
out_8(avr_addr + UART_TX, c);
|
|
out_8(avr_addr + UART_TX, c);
|
|
out_8(avr_addr + UART_TX, c);
|
|
out_8(avr_addr + UART_TX, c);
|
|
}
|
|
|
|
static void __init ls_uart_init(void)
|
|
{
|
|
local_irq_disable();
|
|
|
|
#ifndef CONFIG_SERIAL_8250
|
|
out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
|
|
out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO |
|
|
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); /* clear FIFOs */
|
|
out_8(avr_addr + UART_FCR, 0);
|
|
out_8(avr_addr + UART_IER, 0);
|
|
|
|
/* Clear up interrupts */
|
|
(void) in_8(avr_addr + UART_LSR);
|
|
(void) in_8(avr_addr + UART_RX);
|
|
(void) in_8(avr_addr + UART_IIR);
|
|
(void) in_8(avr_addr + UART_MSR);
|
|
#endif
|
|
avr_uart_configure();
|
|
|
|
local_irq_enable();
|
|
}
|
|
|
|
static int __init ls_uarts_init(void)
|
|
{
|
|
struct device_node *avr;
|
|
phys_addr_t phys_addr;
|
|
int len;
|
|
|
|
avr = of_find_node_by_path("/soc10x/serial@80004500");
|
|
if (!avr)
|
|
return -EINVAL;
|
|
|
|
avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len);
|
|
phys_addr = ((u32*)of_get_property(avr, "reg", &len))[0];
|
|
|
|
if (!avr_clock || !phys_addr)
|
|
return -EINVAL;
|
|
|
|
avr_addr = ioremap(phys_addr, 32);
|
|
if (!avr_addr)
|
|
return -EFAULT;
|
|
|
|
ls_uart_init();
|
|
|
|
INIT_WORK(&wd_work, wd_stop);
|
|
schedule_work(&wd_work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
machine_late_initcall(linkstation, ls_uarts_init);
|