1 /*
2 * arch/cris/kernel/debug.c
3 * Various debug routines:
4 * o Logging of interrupt enabling/disabling. /proc/debug_interrupt
5 * gives result and enables logging when read.
6 *
7 * Copyright (C) 2003 Axis Communications AB
8 */
9
10 #include <linux/config.h>
11 #include <asm/system.h>
12 #include <linux/init.h>
13 #include <linux/proc_fs.h>
14 #include <asm/svinto.h>
15
16 #ifdef CONFIG_ETRAX_DEBUG_INTERRUPT
17 #define LOG_INT_SIZE 8192
18 #define DEBUG_INT_PROC_FILE "debug_interrupt"
19 #define LOG_INT_SHOW_MIN_USEC 45000
20
21 /* These are global and can be used to trig certain events. */
22 int log_int_pos = 0;
23 int log_int_size = LOG_INT_SIZE;
24 int log_int_trig0_pos = 0;
25 int log_int_trig1_pos = 0;
26
27 int log_int_enable = 0; /* Enabled every read of /proc/debug_interrupt */
28
29 struct log_int_struct
30 {
31 unsigned long pc;
32 unsigned long ev_timer_data;
33 };
34
35 static struct log_int_struct log_ints[LOG_INT_SIZE];
36
37 //static unsigned long prev_log_int_t = 0;
38 static unsigned long prev_logged_ccr = 0;
39 static unsigned long prev_ei_timer_data = 0;
40 static unsigned long prev_di_timer_data = 0;
41
42 #define CCR_EI_BIT 5
43 enum {
44 INT_OLD_MASK = 0x01, INT_OLD_BIT = 0,
45 INT_NEW_MASK = 0x02, INT_NEW_BIT = 1,
46 INT_EI_CHANGE_MASK = 0x04, INT_EI_CHANGE_BIT = 2,
47 INT_ACTION_RESTORE = 0x08, INT_ACTION_RESTORE_BIT = 3,
48 INT_ACTION_MISSED = 0x10, INT_ACTION_MISSED_BIT = 4,
49 INT_ACTION_LONG = 0x20, INT_ACTION_LONG_BIT = 5,
50
51 INT_OLD_EI = INT_OLD_MASK, INT_OLD_EI_BIT = INT_OLD_BIT,
52 INT_NEW_EI = INT_NEW_MASK, INT_NEW_EI_BIT = INT_NEW_BIT,
53 INT_EV_DI = INT_OLD_EI | INT_EI_CHANGE_MASK,
54 INT_EV_NOP_DI = 0,
55 INT_EV_EI = INT_NEW_EI | INT_EI_CHANGE_MASK,
56 INT_EV_NOP_EI = INT_OLD_EI | INT_NEW_EI,
57 INT_EV_RESTORE_DI= INT_EV_DI | INT_EI_CHANGE_MASK | INT_ACTION_RESTORE,
58 INT_EV_RESTORE_EI= INT_EV_EI | INT_EI_CHANGE_MASK | INT_ACTION_RESTORE,
59 INT_EV_RESTORE_NOP_DI = INT_EV_NOP_DI | INT_ACTION_RESTORE,
60 INT_EV_RESTORE_NOP_EI = INT_EV_NOP_EI | INT_ACTION_RESTORE,
61 };
62
log_int(unsigned long pc,unsigned long curr_ccr,unsigned long next_ccr)63 void log_int(unsigned long pc, unsigned long curr_ccr, unsigned long next_ccr)
64 {
65 unsigned long t;
66 int ev;
67 static int no_change_cnt = 0;
68
69 /* Just disable interrupts without logging here,
70 * the caller will either do ei, di or restore
71 */
72 __asm__ __volatile__ ("di" : : :"memory");
73 t = *R_TIMER_DATA;
74
75 if (curr_ccr & CCR_EI_MASK) {
76 prev_ei_timer_data = t;
77 ev = INT_OLD_EI;
78 } else {
79 prev_di_timer_data = t;
80 if ( (((prev_ei_timer_data >> 8) & 0x000000FF) -
81 ((prev_di_timer_data >> 8) & 0x000000FF)) & ~0x03)
82 ev = INT_ACTION_LONG;
83 else
84 ev = 0;
85 }
86 if ((curr_ccr ^ prev_logged_ccr) & CCR_EI_MASK)
87 ev |= INT_ACTION_MISSED;
88 if (next_ccr & CCR_EI_MASK)
89 ev |= INT_NEW_EI;
90 if ((curr_ccr ^ next_ccr) & CCR_EI_MASK) {
91 ev |= INT_EI_CHANGE_MASK;
92 no_change_cnt = 0;
93 } else
94 no_change_cnt++;
95
96 prev_logged_ccr = next_ccr;
97
98 if (log_int_enable &&
99 ((ev & (INT_EI_CHANGE_MASK | INT_ACTION_MISSED | INT_ACTION_LONG))
100 || (no_change_cnt < 40)) &&
101 log_int_pos < LOG_INT_SIZE) {
102 int i;
103 i = log_int_pos;
104 log_int_pos++;
105 log_ints[i].pc = pc;
106 log_ints[i].ev_timer_data = (t & 0x00FFFFFF) |
107 ((ev & 0xFF) << 24);
108
109 }
110 // __asm__ __volatile__ ("move %0,$ccr" : : "rm" (curr_ccr) : "memory");
111 }
log_int_di(void)112 void log_int_di(void)
113 {
114 unsigned long pc;
115 unsigned long flags;
116 __asm__ __volatile__ ("move $srp,%0" : "=rm" (pc) : : "memory");
117 __asm__ __volatile__ ("move $ccr,%0" : "=rm" (flags) : : "memory");
118 log_int(pc, flags, 0);
119 }
120
log_int_ei(void)121 void log_int_ei(void)
122 {
123 unsigned long pc;
124 unsigned long flags;
125 __asm__ __volatile__ ("move $srp,%0" : "=rm" (pc) : : "memory");
126 __asm__ __volatile__ ("move $ccr,%0" : "=rm" (flags) : : "memory");
127 log_int(pc, flags, CCR_EI_MASK);
128 }
129
130
log_int_read_proc(char * page,char ** start,off_t off,int count,int * eof,void * data)131 static int log_int_read_proc(char *page, char **start, off_t off, int count,
132 int *eof, void *data)
133 {
134 int i, len = 0;
135 off_t begin = 0;
136 int j, t0, t1, t, thigh, tlow, tdi0;
137 int di0, ei1;
138 len += sprintf(page + len, "trig0: %i trig1: %i\n", log_int_trig0_pos, log_int_trig1_pos);
139 for (i = 0; i < log_int_pos-1; i++) {
140
141 if (((log_ints[i].ev_timer_data >> 24) & INT_NEW_EI)) {
142 di0 = i;
143 while (di0 < log_int_pos-1 && (((log_ints[di0].ev_timer_data >> 24) & INT_NEW_EI)))
144 di0++;
145 ei1 = di0+1;
146 while (ei1 < log_int_pos-1 && (((log_ints[ei1].ev_timer_data >> 24) & INT_NEW_EI) == 0))
147 ei1++;
148 thigh = timer_data_to_ns(log_ints[ei1].ev_timer_data);
149 tlow = timer_data_to_ns(log_ints[di0].ev_timer_data);
150 tdi0 = timer_data_to_ns(log_ints[di0].ev_timer_data);
151
152 t = thigh-tlow;
153 j = di0-1;
154 if ((t > LOG_INT_SHOW_MIN_USEC) || (log_int_trig0_pos-30 < j && j < log_int_trig1_pos+30)) {
155
156 for (; j <= ei1; j++) {
157 t0 = ((log_ints[j+1].ev_timer_data & 0xFF) -
158 (log_ints[j].ev_timer_data & 0xFF));
159 t1 = (((log_ints[j+1].ev_timer_data >> 8) & 0xFF) -
160 ((log_ints[j].ev_timer_data >> 8) & 0xFF));
161 if (t1 == 0 || t1 == 1) {
162 if (t0 < 0)
163 t0 += 256;
164 } else {
165 if (t1 < 0)
166 t1 += 256;
167 }
168 thigh = timer_data_to_ns(log_ints[j+1].ev_timer_data);
169 tlow = timer_data_to_ns(log_ints[j].ev_timer_data);
170 t = thigh-tlow;
171 len += sprintf(page + len, "%4i PC %08lX-%08lX %08lX-%08lX %s high %i in %-6i ns %-7i to %-7i = %-5i ns, from first di %i ns %s\n",
172 j, log_ints[j].pc, log_ints[j+1].pc,
173 log_ints[j].ev_timer_data, log_ints[j+1].ev_timer_data,
174 ((log_ints[j].ev_timer_data >> 24) & INT_NEW_EI)!= 0?"ei":"di", t1, t,
175 tlow, thigh, thigh-tlow, thigh-tdi0,
176 j==log_int_trig0_pos?"TRIG0":(j==log_int_trig1_pos?"TRIG1":""));
177 if (len+begin > off+count)
178 goto done;
179 if (len+begin < off) {
180 begin += len;
181 len = 0;
182 }
183 }
184
185 len += sprintf(page + len,"\n");
186 i = ei1-2;
187 }
188
189 }
190
191 }
192 log_int_enable = 1;
193 log_int_pos = 0;
194 log_int_trig0_pos = 0;
195 log_int_trig1_pos = 0;
196 *eof = 1;
197 done:
198 if (off >= len+begin)
199 return 0;
200 *start = page + (off-begin);
201 return ((count < begin+len-off) ? count : begin+len-off);
202 }
203
204 static int __init
log_int_init(void)205 log_int_init(void)
206 {
207 create_proc_read_entry (DEBUG_INT_PROC_FILE, 0, 0, log_int_read_proc, NULL);
208 printk(KERN_INFO "/proc/" DEBUG_INT_PROC_FILE " size %i.\r\n",
209 LOG_INT_SIZE);
210 return 0;
211 }
212 module_init(log_int_init);
213 #endif /* CONFIG_ETRAX_DEBUG_INTERRUPT */
214