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1/*
2 * AVR power-management chip interface for the Buffalo Linkstation /
3 * Kurobox Platform.
4 *
5 * Author: 2006 (c) G. Liakhovetski
6 * g.liakhovetski@gmx.de
7 *
8 * This file is licensed under the terms of the GNU General Public License
9 * version 2. This program is licensed "as is" without any warranty of
10 * any kind, whether express or implied.
11 */
12#include <linux/workqueue.h>
13#include <linux/string.h>
14#include <linux/delay.h>
15#include <linux/serial_reg.h>
16#include <linux/serial_8250.h>
17#include <linux/of.h>
18#include <linux/of_address.h>
19#include <asm/io.h>
20#include <asm/termbits.h>
21
22#include "mpc10x.h"
23
24static void __iomem *avr_addr;
25static unsigned long avr_clock;
26
27static struct work_struct wd_work;
28
29static void wd_stop(struct work_struct *unused)
30{
31 const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK";
32 int i = 0, rescue = 8;
33 int len = strlen(string);
34
35 while (rescue--) {
36 int j;
37 char lsr = in_8(avr_addr + UART_LSR);
38
39 if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) {
40 for (j = 0; j < 16 && i < len; j++, i++)
41 out_8(avr_addr + UART_TX, string[i]);
42 if (i == len) {
43 /* Read "OK" back: 4ms for the last "KKKK"
44 plus a couple bytes back */
45 msleep(7);
46 printk("linkstation: disarming the AVR watchdog: ");
47 while (in_8(avr_addr + UART_LSR) & UART_LSR_DR)
48 printk("%c", in_8(avr_addr + UART_RX));
49 break;
50 }
51 }
52 msleep(17);
53 }
54 printk("\n");
55}
56
57#define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600)
58
59void avr_uart_configure(void)
60{
61 unsigned char cval = UART_LCR_WLEN8;
62 unsigned int quot = AVR_QUOT(avr_clock);
63
64 if (!avr_addr || !avr_clock)
65 return;
66
67 out_8(avr_addr + UART_LCR, cval); /* initialise UART */
68 out_8(avr_addr + UART_MCR, 0);
69 out_8(avr_addr + UART_IER, 0);
70
71 cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR;
72
73 out_8(avr_addr + UART_LCR, cval); /* Set character format */
74
75 out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
76 out_8(avr_addr + UART_DLL, quot & 0xff); /* LS of divisor */
77 out_8(avr_addr + UART_DLM, quot >> 8); /* MS of divisor */
78 out_8(avr_addr + UART_LCR, cval); /* reset DLAB */
79 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
80}
81
82void avr_uart_send(const char c)
83{
84 if (!avr_addr || !avr_clock)
85 return;
86
87 out_8(avr_addr + UART_TX, c);
88 out_8(avr_addr + UART_TX, c);
89 out_8(avr_addr + UART_TX, c);
90 out_8(avr_addr + UART_TX, c);
91}
92
93static void __init ls_uart_init(void)
94{
95 local_irq_disable();
96
97#ifndef CONFIG_SERIAL_8250
98 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
99 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO |
100 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); /* clear FIFOs */
101 out_8(avr_addr + UART_FCR, 0);
102 out_8(avr_addr + UART_IER, 0);
103
104 /* Clear up interrupts */
105 (void) in_8(avr_addr + UART_LSR);
106 (void) in_8(avr_addr + UART_RX);
107 (void) in_8(avr_addr + UART_IIR);
108 (void) in_8(avr_addr + UART_MSR);
109#endif
110 avr_uart_configure();
111
112 local_irq_enable();
113}
114
115static int __init ls_uarts_init(void)
116{
117 struct device_node *avr;
118 struct resource res;
119 int len, ret;
120
121 avr = of_find_node_by_path("/soc10x/serial@80004500");
122 if (!avr)
123 return -EINVAL;
124
125 avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len);
126 if (!avr_clock)
127 return -EINVAL;
128
129 ret = of_address_to_resource(avr, 0, &res);
130 if (ret)
131 return ret;
132
133 of_node_put(avr);
134
135 avr_addr = ioremap(res.start, 32);
136 if (!avr_addr)
137 return -EFAULT;
138
139 ls_uart_init();
140
141 INIT_WORK(&wd_work, wd_stop);
142 schedule_work(&wd_work);
143
144 return 0;
145}
146
147machine_late_initcall(linkstation, ls_uarts_init);
1/*
2 * AVR power-management chip interface for the Buffalo Linkstation /
3 * Kurobox Platform.
4 *
5 * Author: 2006 (c) G. Liakhovetski
6 * g.liakhovetski@gmx.de
7 *
8 * This file is licensed under the terms of the GNU General Public License
9 * version 2. This program is licensed "as is" without any warranty of
10 * any kind, whether express or implied.
11 */
12#include <linux/workqueue.h>
13#include <linux/string.h>
14#include <linux/delay.h>
15#include <linux/serial_reg.h>
16#include <linux/serial_8250.h>
17#include <asm/io.h>
18#include <asm/prom.h>
19#include <asm/termbits.h>
20
21#include "mpc10x.h"
22
23static void __iomem *avr_addr;
24static unsigned long avr_clock;
25
26static struct work_struct wd_work;
27
28static void wd_stop(struct work_struct *unused)
29{
30 const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK";
31 int i = 0, rescue = 8;
32 int len = strlen(string);
33
34 while (rescue--) {
35 int j;
36 char lsr = in_8(avr_addr + UART_LSR);
37
38 if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) {
39 for (j = 0; j < 16 && i < len; j++, i++)
40 out_8(avr_addr + UART_TX, string[i]);
41 if (i == len) {
42 /* Read "OK" back: 4ms for the last "KKKK"
43 plus a couple bytes back */
44 msleep(7);
45 printk("linkstation: disarming the AVR watchdog: ");
46 while (in_8(avr_addr + UART_LSR) & UART_LSR_DR)
47 printk("%c", in_8(avr_addr + UART_RX));
48 break;
49 }
50 }
51 msleep(17);
52 }
53 printk("\n");
54}
55
56#define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600)
57
58void avr_uart_configure(void)
59{
60 unsigned char cval = UART_LCR_WLEN8;
61 unsigned int quot = AVR_QUOT(avr_clock);
62
63 if (!avr_addr || !avr_clock)
64 return;
65
66 out_8(avr_addr + UART_LCR, cval); /* initialise UART */
67 out_8(avr_addr + UART_MCR, 0);
68 out_8(avr_addr + UART_IER, 0);
69
70 cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR;
71
72 out_8(avr_addr + UART_LCR, cval); /* Set character format */
73
74 out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
75 out_8(avr_addr + UART_DLL, quot & 0xff); /* LS of divisor */
76 out_8(avr_addr + UART_DLM, quot >> 8); /* MS of divisor */
77 out_8(avr_addr + UART_LCR, cval); /* reset DLAB */
78 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
79}
80
81void avr_uart_send(const char c)
82{
83 if (!avr_addr || !avr_clock)
84 return;
85
86 out_8(avr_addr + UART_TX, c);
87 out_8(avr_addr + UART_TX, c);
88 out_8(avr_addr + UART_TX, c);
89 out_8(avr_addr + UART_TX, c);
90}
91
92static void __init ls_uart_init(void)
93{
94 local_irq_disable();
95
96#ifndef CONFIG_SERIAL_8250
97 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */
98 out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO |
99 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); /* clear FIFOs */
100 out_8(avr_addr + UART_FCR, 0);
101 out_8(avr_addr + UART_IER, 0);
102
103 /* Clear up interrupts */
104 (void) in_8(avr_addr + UART_LSR);
105 (void) in_8(avr_addr + UART_RX);
106 (void) in_8(avr_addr + UART_IIR);
107 (void) in_8(avr_addr + UART_MSR);
108#endif
109 avr_uart_configure();
110
111 local_irq_enable();
112}
113
114static int __init ls_uarts_init(void)
115{
116 struct device_node *avr;
117 phys_addr_t phys_addr;
118 int len;
119
120 avr = of_find_node_by_path("/soc10x/serial@80004500");
121 if (!avr)
122 return -EINVAL;
123
124 avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len);
125 phys_addr = ((u32*)of_get_property(avr, "reg", &len))[0];
126
127 if (!avr_clock || !phys_addr)
128 return -EINVAL;
129
130 avr_addr = ioremap(phys_addr, 32);
131 if (!avr_addr)
132 return -EFAULT;
133
134 ls_uart_init();
135
136 INIT_WORK(&wd_work, wd_stop);
137 schedule_work(&wd_work);
138
139 return 0;
140}
141
142machine_late_initcall(linkstation, ls_uarts_init);