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1/* debug-stub.c: debug-mode stub
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/string.h>
13#include <linux/kernel.h>
14#include <linux/signal.h>
15#include <linux/sched.h>
16#include <linux/init.h>
17#include <linux/serial_reg.h>
18#include <linux/start_kernel.h>
19
20#include <asm/serial-regs.h>
21#include <asm/timer-regs.h>
22#include <asm/irc-regs.h>
23#include <asm/gdb-stub.h>
24#include "gdb-io.h"
25
26/* CPU board CON5 */
27#define __UART0(X) (*(volatile uint8_t *)(UART0_BASE + (UART_##X)))
28
29#define LSR_WAIT_FOR0(STATE) \
30do { \
31} while (!(__UART0(LSR) & UART_LSR_##STATE))
32
33#define FLOWCTL_QUERY0(LINE) ({ __UART0(MSR) & UART_MSR_##LINE; })
34#define FLOWCTL_CLEAR0(LINE) do { __UART0(MCR) &= ~UART_MCR_##LINE; } while (0)
35#define FLOWCTL_SET0(LINE) do { __UART0(MCR) |= UART_MCR_##LINE; } while (0)
36
37#define FLOWCTL_WAIT_FOR0(LINE) \
38do { \
39 gdbstub_do_rx(); \
40} while(!FLOWCTL_QUERY(LINE))
41
42struct frv_debug_status __debug_status;
43
44static void __init debug_stub_init(void);
45
46/*****************************************************************************/
47/*
48 * debug mode handler stub
49 * - we come here with the CPU in debug mode and with exceptions disabled
50 * - handle debugging services for userspace
51 */
52asmlinkage void debug_stub(void)
53{
54 unsigned long hsr0;
55 int type = 0;
56
57 static u8 inited = 0;
58 if (!inited) {
59 debug_stub_init();
60 type = -1;
61 inited = 1;
62 }
63
64 hsr0 = __get_HSR(0);
65 if (hsr0 & HSR0_ETMD)
66 __set_HSR(0, hsr0 & ~HSR0_ETMD);
67
68 /* disable single stepping */
69 __debug_status.dcr &= ~DCR_SE;
70
71 /* kernel mode can propose an exception be handled in debug mode by jumping to a special
72 * location */
73 if (__debug_frame->pc == (unsigned long) __break_hijack_kernel_event_breaks_here) {
74 /* replace the debug frame with the kernel frame and discard
75 * the top kernel context */
76 *__debug_frame = *__frame;
77 __frame = __debug_frame->next_frame;
78 __debug_status.brr = (__debug_frame->tbr & TBR_TT) << 12;
79 __debug_status.brr |= BRR_EB;
80 }
81
82 if (__debug_frame->pc == (unsigned long) __debug_bug_trap + 4) {
83 __debug_frame->pc = __debug_frame->lr;
84 type = __debug_frame->gr8;
85 }
86
87#ifdef CONFIG_GDBSTUB
88 gdbstub(type);
89#endif
90
91 if (hsr0 & HSR0_ETMD)
92 __set_HSR(0, __get_HSR(0) | HSR0_ETMD);
93
94} /* end debug_stub() */
95
96/*****************************************************************************/
97/*
98 * debug stub initialisation
99 */
100static void __init debug_stub_init(void)
101{
102 __set_IRR(6, 0xff000000); /* map ERRs to NMI */
103 __set_IITMR(1, 0x20000000); /* ERR0/1, UART0/1 IRQ detect levels */
104
105 asm volatile(" movgs gr0,ibar0 \n"
106 " movgs gr0,ibar1 \n"
107 " movgs gr0,ibar2 \n"
108 " movgs gr0,ibar3 \n"
109 " movgs gr0,dbar0 \n"
110 " movgs gr0,dbmr00 \n"
111 " movgs gr0,dbmr01 \n"
112 " movgs gr0,dbdr00 \n"
113 " movgs gr0,dbdr01 \n"
114 " movgs gr0,dbar1 \n"
115 " movgs gr0,dbmr10 \n"
116 " movgs gr0,dbmr11 \n"
117 " movgs gr0,dbdr10 \n"
118 " movgs gr0,dbdr11 \n"
119 );
120
121 /* deal with debugging stub initialisation and initial pause */
122 if (__debug_frame->pc == (unsigned long) __debug_stub_init_break)
123 __debug_frame->pc = (unsigned long) start_kernel;
124
125 /* enable the debug events we want to trap */
126 __debug_status.dcr = DCR_EBE;
127
128#ifdef CONFIG_GDBSTUB
129 gdbstub_init();
130#endif
131
132 __clr_MASK_all();
133 __clr_MASK(15);
134 __clr_RC(15);
135
136} /* end debug_stub_init() */
137
138/*****************************************************************************/
139/*
140 * kernel "exit" trap for gdb stub
141 */
142void debug_stub_exit(int status)
143{
144
145#ifdef CONFIG_GDBSTUB
146 gdbstub_exit(status);
147#endif
148
149} /* end debug_stub_exit() */
150
151/*****************************************************************************/
152/*
153 * send string to serial port
154 */
155void debug_to_serial(const char *p, int n)
156{
157 char ch;
158
159 for (; n > 0; n--) {
160 ch = *p++;
161 FLOWCTL_SET0(DTR);
162 LSR_WAIT_FOR0(THRE);
163 // FLOWCTL_WAIT_FOR(CTS);
164
165 if (ch == 0x0a) {
166 __UART0(TX) = 0x0d;
167 mb();
168 LSR_WAIT_FOR0(THRE);
169 // FLOWCTL_WAIT_FOR(CTS);
170 }
171 __UART0(TX) = ch;
172 mb();
173
174 FLOWCTL_CLEAR0(DTR);
175 }
176
177} /* end debug_to_serial() */
178
179/*****************************************************************************/
180/*
181 * send string to serial port
182 */
183void debug_to_serial2(const char *fmt, ...)
184{
185 va_list va;
186 char buf[64];
187 int n;
188
189 va_start(va, fmt);
190 n = vsprintf(buf, fmt, va);
191 va_end(va);
192
193 debug_to_serial(buf, n);
194
195} /* end debug_to_serial2() */
196
197/*****************************************************************************/
198/*
199 * set up the ttyS0 serial port baud rate timers
200 */
201void __init console_set_baud(unsigned baud)
202{
203 unsigned value, high, low;
204 u8 lcr;
205
206 /* work out the divisor to give us the nearest higher baud rate */
207 value = __serial_clock_speed_HZ / 16 / baud;
208
209 /* determine the baud rate range */
210 high = __serial_clock_speed_HZ / 16 / value;
211 low = __serial_clock_speed_HZ / 16 / (value + 1);
212
213 /* pick the nearest bound */
214 if (low + (high - low) / 2 > baud)
215 value++;
216
217 lcr = __UART0(LCR);
218 __UART0(LCR) |= UART_LCR_DLAB;
219 mb();
220 __UART0(DLL) = value & 0xff;
221 __UART0(DLM) = (value >> 8) & 0xff;
222 mb();
223 __UART0(LCR) = lcr;
224 mb();
225
226} /* end console_set_baud() */
227
228/*****************************************************************************/
229/*
230 *
231 */
232int __init console_get_baud(void)
233{
234 unsigned value;
235 u8 lcr;
236
237 lcr = __UART0(LCR);
238 __UART0(LCR) |= UART_LCR_DLAB;
239 mb();
240 value = __UART0(DLM) << 8;
241 value |= __UART0(DLL);
242 __UART0(LCR) = lcr;
243 mb();
244
245 return value;
246} /* end console_get_baud() */
247
248/*****************************************************************************/
249/*
250 * display BUG() info
251 */
252#ifndef CONFIG_NO_KERNEL_MSG
253void __debug_bug_printk(const char *file, unsigned line)
254{
255 printk("kernel BUG at %s:%d!\n", file, line);
256
257} /* end __debug_bug_printk() */
258#endif
1/* debug-stub.c: debug-mode stub
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/string.h>
13#include <linux/kernel.h>
14#include <linux/signal.h>
15#include <linux/sched.h>
16#include <linux/init.h>
17#include <linux/serial_reg.h>
18#include <linux/start_kernel.h>
19
20#include <asm/serial-regs.h>
21#include <asm/timer-regs.h>
22#include <asm/irc-regs.h>
23#include <asm/gdb-stub.h>
24#include "gdb-io.h"
25
26/* CPU board CON5 */
27#define __UART0(X) (*(volatile uint8_t *)(UART0_BASE + (UART_##X)))
28
29#define LSR_WAIT_FOR0(STATE) \
30do { \
31} while (!(__UART0(LSR) & UART_LSR_##STATE))
32
33#define FLOWCTL_QUERY0(LINE) ({ __UART0(MSR) & UART_MSR_##LINE; })
34#define FLOWCTL_CLEAR0(LINE) do { __UART0(MCR) &= ~UART_MCR_##LINE; } while (0)
35#define FLOWCTL_SET0(LINE) do { __UART0(MCR) |= UART_MCR_##LINE; } while (0)
36
37#define FLOWCTL_WAIT_FOR0(LINE) \
38do { \
39 gdbstub_do_rx(); \
40} while(!FLOWCTL_QUERY(LINE))
41
42struct frv_debug_status __debug_status;
43
44static void __init debug_stub_init(void);
45
46/*****************************************************************************/
47/*
48 * debug mode handler stub
49 * - we come here with the CPU in debug mode and with exceptions disabled
50 * - handle debugging services for userspace
51 */
52asmlinkage void debug_stub(void)
53{
54 unsigned long hsr0;
55 int type = 0;
56
57 static u8 inited = 0;
58 if (!inited) {
59 debug_stub_init();
60 type = -1;
61 inited = 1;
62 }
63
64 hsr0 = __get_HSR(0);
65 if (hsr0 & HSR0_ETMD)
66 __set_HSR(0, hsr0 & ~HSR0_ETMD);
67
68 /* disable single stepping */
69 __debug_status.dcr &= ~DCR_SE;
70
71 /* kernel mode can propose an exception be handled in debug mode by jumping to a special
72 * location */
73 if (__debug_frame->pc == (unsigned long) __break_hijack_kernel_event_breaks_here) {
74 /* replace the debug frame with the kernel frame and discard
75 * the top kernel context */
76 *__debug_frame = *__frame;
77 __frame = __debug_frame->next_frame;
78 __debug_status.brr = (__debug_frame->tbr & TBR_TT) << 12;
79 __debug_status.brr |= BRR_EB;
80 }
81
82 if (__debug_frame->pc == (unsigned long) __debug_bug_trap + 4) {
83 __debug_frame->pc = __debug_frame->lr;
84 type = __debug_frame->gr8;
85 }
86
87#ifdef CONFIG_GDBSTUB
88 gdbstub(type);
89#endif
90
91 if (hsr0 & HSR0_ETMD)
92 __set_HSR(0, __get_HSR(0) | HSR0_ETMD);
93
94} /* end debug_stub() */
95
96/*****************************************************************************/
97/*
98 * debug stub initialisation
99 */
100static void __init debug_stub_init(void)
101{
102 __set_IRR(6, 0xff000000); /* map ERRs to NMI */
103 __set_IITMR(1, 0x20000000); /* ERR0/1, UART0/1 IRQ detect levels */
104
105 asm volatile(" movgs gr0,ibar0 \n"
106 " movgs gr0,ibar1 \n"
107 " movgs gr0,ibar2 \n"
108 " movgs gr0,ibar3 \n"
109 " movgs gr0,dbar0 \n"
110 " movgs gr0,dbmr00 \n"
111 " movgs gr0,dbmr01 \n"
112 " movgs gr0,dbdr00 \n"
113 " movgs gr0,dbdr01 \n"
114 " movgs gr0,dbar1 \n"
115 " movgs gr0,dbmr10 \n"
116 " movgs gr0,dbmr11 \n"
117 " movgs gr0,dbdr10 \n"
118 " movgs gr0,dbdr11 \n"
119 );
120
121 /* deal with debugging stub initialisation and initial pause */
122 if (__debug_frame->pc == (unsigned long) __debug_stub_init_break)
123 __debug_frame->pc = (unsigned long) start_kernel;
124
125 /* enable the debug events we want to trap */
126 __debug_status.dcr = DCR_EBE;
127
128#ifdef CONFIG_GDBSTUB
129 gdbstub_init();
130#endif
131
132 __clr_MASK_all();
133 __clr_MASK(15);
134 __clr_RC(15);
135
136} /* end debug_stub_init() */
137
138/*****************************************************************************/
139/*
140 * kernel "exit" trap for gdb stub
141 */
142void debug_stub_exit(int status)
143{
144
145#ifdef CONFIG_GDBSTUB
146 gdbstub_exit(status);
147#endif
148
149} /* end debug_stub_exit() */
150
151/*****************************************************************************/
152/*
153 * send string to serial port
154 */
155void debug_to_serial(const char *p, int n)
156{
157 char ch;
158
159 for (; n > 0; n--) {
160 ch = *p++;
161 FLOWCTL_SET0(DTR);
162 LSR_WAIT_FOR0(THRE);
163 // FLOWCTL_WAIT_FOR(CTS);
164
165 if (ch == 0x0a) {
166 __UART0(TX) = 0x0d;
167 mb();
168 LSR_WAIT_FOR0(THRE);
169 // FLOWCTL_WAIT_FOR(CTS);
170 }
171 __UART0(TX) = ch;
172 mb();
173
174 FLOWCTL_CLEAR0(DTR);
175 }
176
177} /* end debug_to_serial() */
178
179/*****************************************************************************/
180/*
181 * send string to serial port
182 */
183void debug_to_serial2(const char *fmt, ...)
184{
185 va_list va;
186 char buf[64];
187 int n;
188
189 va_start(va, fmt);
190 n = vsprintf(buf, fmt, va);
191 va_end(va);
192
193 debug_to_serial(buf, n);
194
195} /* end debug_to_serial2() */
196
197/*****************************************************************************/
198/*
199 * set up the ttyS0 serial port baud rate timers
200 */
201void __init console_set_baud(unsigned baud)
202{
203 unsigned value, high, low;
204 u8 lcr;
205
206 /* work out the divisor to give us the nearest higher baud rate */
207 value = __serial_clock_speed_HZ / 16 / baud;
208
209 /* determine the baud rate range */
210 high = __serial_clock_speed_HZ / 16 / value;
211 low = __serial_clock_speed_HZ / 16 / (value + 1);
212
213 /* pick the nearest bound */
214 if (low + (high - low) / 2 > baud)
215 value++;
216
217 lcr = __UART0(LCR);
218 __UART0(LCR) |= UART_LCR_DLAB;
219 mb();
220 __UART0(DLL) = value & 0xff;
221 __UART0(DLM) = (value >> 8) & 0xff;
222 mb();
223 __UART0(LCR) = lcr;
224 mb();
225
226} /* end console_set_baud() */
227
228/*****************************************************************************/
229/*
230 *
231 */
232int __init console_get_baud(void)
233{
234 unsigned value;
235 u8 lcr;
236
237 lcr = __UART0(LCR);
238 __UART0(LCR) |= UART_LCR_DLAB;
239 mb();
240 value = __UART0(DLM) << 8;
241 value |= __UART0(DLL);
242 __UART0(LCR) = lcr;
243 mb();
244
245 return value;
246} /* end console_get_baud() */
247
248/*****************************************************************************/
249/*
250 * display BUG() info
251 */
252#ifndef CONFIG_NO_KERNEL_MSG
253void __debug_bug_printk(const char *file, unsigned line)
254{
255 printk("kernel BUG at %s:%d!\n", file, line);
256
257} /* end __debug_bug_printk() */
258#endif