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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 | /* * 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 <linux/of.h> #include <asm/io.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]; of_node_put(avr); 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); |