1#include <linux/workqueue.h> 2#include <linux/string.h> 3#include <linux/delay.h> 4#include <linux/serial_reg.h> 5#include <linux/serial_8250.h> 6#include <asm/io.h> 7#include <asm/mpc10x.h> 8#include <asm/ppc_sys.h> 9#include <asm/prom.h> 10#include <asm/termbits.h> 11 12static void __iomem *avr_addr; 13static unsigned long avr_clock; 14 15static struct work_struct wd_work; 16 17static void wd_stop(struct work_struct *unused) 18{ 19 const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK"; 20 int i = 0, rescue = 8; 21 int len = strlen(string); 22 23 while (rescue--) { 24 int j; 25 char lsr = in_8(avr_addr + UART_LSR); 26 27 if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) { 28 for (j = 0; j < 16 && i < len; j++, i++) 29 out_8(avr_addr + UART_TX, string[i]); 30 if (i == len) { 31 /* Read "OK" back: 4ms for the last "KKKK" 32 plus a couple bytes back */ 33 msleep(7); 34 printk("linkstation: disarming the AVR watchdog: "); 35 while (in_8(avr_addr + UART_LSR) & UART_LSR_DR) 36 printk("%c", in_8(avr_addr + UART_RX)); 37 break; 38 } 39 } 40 msleep(17); 41 } 42 printk("\n"); 43} 44 45#define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600) 46 47void avr_uart_configure(void) 48{ 49 unsigned char cval = UART_LCR_WLEN8; 50 unsigned int quot = AVR_QUOT(avr_clock); 51 52 if (!avr_addr || !avr_clock) 53 return; 54 55 out_8(avr_addr + UART_LCR, cval); /* initialise UART */ 56 out_8(avr_addr + UART_MCR, 0); 57 out_8(avr_addr + UART_IER, 0); 58 59 cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR; 60 61 out_8(avr_addr + UART_LCR, cval); /* Set character format */ 62 63 out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */ 64 out_8(avr_addr + UART_DLL, quot & 0xff); /* LS of divisor */ 65 out_8(avr_addr + UART_DLM, quot >> 8); /* MS of divisor */ 66 out_8(avr_addr + UART_LCR, cval); /* reset DLAB */ 67 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */ 68} 69 70void avr_uart_send(const char c) 71{ 72 if (!avr_addr || !avr_clock) 73 return; 74 75 out_8(avr_addr + UART_TX, c); 76 out_8(avr_addr + UART_TX, c); 77 out_8(avr_addr + UART_TX, c); 78 out_8(avr_addr + UART_TX, c); 79} 80 81static void __init ls_uart_init(void) 82{ 83 local_irq_disable(); 84 85#ifndef CONFIG_SERIAL_8250 86 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */ 87 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO | 88 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); /* clear FIFOs */ 89 out_8(avr_addr + UART_FCR, 0); 90 out_8(avr_addr + UART_IER, 0); 91 92 /* Clear up interrupts */ 93 (void) in_8(avr_addr + UART_LSR); 94 (void) in_8(avr_addr + UART_RX); 95 (void) in_8(avr_addr + UART_IIR); 96 (void) in_8(avr_addr + UART_MSR); 97#endif 98 avr_uart_configure(); 99 100 local_irq_enable(); 101} 102 103static int __init ls_uarts_init(void) 104{ 105 struct device_node *avr; 106 phys_addr_t phys_addr; 107 int len; 108 109 avr = of_find_node_by_path("/soc10x/serial@80004500"); 110 if (!avr) 111 return -EINVAL; 112 113 avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len); 114 phys_addr = ((u32*)of_get_property(avr, "reg", &len))[0]; 115 116 if (!avr_clock || !phys_addr) 117 return -EINVAL; 118 119 avr_addr = ioremap(phys_addr, 32); 120 if (!avr_addr) 121 return -EFAULT; 122 123 ls_uart_init(); 124 125 INIT_WORK(&wd_work, wd_stop); 126 schedule_work(&wd_work); 127 128 return 0; 129} 130 131late_initcall(ls_uarts_init); 132