1 #include <rtthread.h>
2 #include <asm/processor.h>
3 #include <asm/ppc4xx-uic.h>
4
5 /* Returns 0 if exception not found and fixup otherwise. */
6 extern unsigned long search_exception_table(unsigned long);
7
8 /* THIS NEEDS CHANGING to use the board info structure.
9 */
10 #define END_OF_MEM 0x800000
11 #define UICB0_ALL 0
12
13 #define ESR_MCI 0x80000000
14 #define ESR_PIL 0x08000000
15 #define ESR_PPR 0x04000000
16 #define ESR_PTR 0x02000000
17 #define ESR_DST 0x00800000
18 #define ESR_DIZ 0x00400000
19 #define ESR_U0F 0x00008000
20
set_tsr(unsigned long val)21 rt_inline void set_tsr(unsigned long val)
22 {
23 mtspr(SPRN_TSR, val);
24 }
25
get_esr(void)26 rt_inline rt_uint32_t get_esr(void)
27 {
28 rt_uint32_t val;
29
30 val = mfspr(SPRN_ESR);
31 return val;
32 }
33
34 /*
35 * Trap & Exception support
36 */
37
print_backtrace(unsigned long * sp)38 void print_backtrace(unsigned long *sp)
39 {
40 int cnt = 0;
41 unsigned long i;
42
43 rt_kprintf("Call backtrace: ");
44 while (sp) {
45 if ((rt_uint32_t)sp > END_OF_MEM)
46 break;
47
48 i = sp[1];
49 if (cnt++ % 7 == 0)
50 rt_kprintf("\n");
51 rt_kprintf("%08lX ", i);
52 if (cnt > 32) break;
53 sp = (unsigned long *)*sp;
54 }
55 rt_kprintf("\n");
56 }
57
show_regs(struct pt_regs * regs)58 void show_regs(struct pt_regs * regs)
59 {
60 int i;
61
62 rt_kprintf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DEAR: %08lX\n",
63 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
64 rt_kprintf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
65 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
66 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
67 regs->msr&MSR_IR ? 1 : 0,
68 regs->msr&MSR_DR ? 1 : 0);
69
70 rt_kprintf("\n");
71 for (i = 0; i < 32; i++) {
72 if ((i % 8) == 0) {
73 rt_kprintf("GPR%02d: ", i);
74 }
75
76 rt_kprintf("%08lX ", regs->gpr[i]);
77 if ((i % 8) == 7) {
78 rt_kprintf("\n");
79 }
80 }
81 }
82
panic(const char * fmt,...)83 void panic(const char *fmt, ...)
84 {
85 while(1);
86 }
87
88 void
_exception(int signr,struct pt_regs * regs)89 _exception(int signr, struct pt_regs *regs)
90 {
91 show_regs(regs);
92 print_backtrace((unsigned long *)regs->gpr[1]);
93 panic("Exception");
94 }
95
96 unsigned long
search_exception_table(unsigned long addr)97 search_exception_table(unsigned long addr)
98 {
99 unsigned long ret = 0;
100
101 /* There is only the kernel to search. */
102 // ret = search_one_table(__start___ex_table, __stop___ex_table-1, addr);
103 /* if the serial port does not hang in exception, rt_kprintf can be used */
104 if (ret) return ret;
105
106 return 0;
107 }
108
109 /*
110 * Handle external interrupts
111 */
external_interrupt(struct pt_regs * regs)112 void external_interrupt(struct pt_regs *regs)
113 {
114 u32 uic_msr;
115
116 /*
117 * Read masked interrupt status register to determine interrupt source
118 */
119 uic_msr = mfdcr(uic0msr);
120
121 mtdcr(uic0sr, (uic_msr & UICB0_ALL));
122
123 if (uic_msr & ~(UICB0_ALL))
124 {
125 uic_interrupt(UIC0_DCR_BASE, 0);
126 }
127
128 return;
129 }
130
MachineCheckException(struct pt_regs * regs)131 void MachineCheckException(struct pt_regs *regs)
132 {
133 unsigned long fixup, val;
134
135 if ((fixup = search_exception_table(regs->nip)) != 0) {
136 regs->nip = fixup;
137 val = mfspr(MCSR);
138 /* Clear MCSR */
139 mtspr(SPRN_MCSR, val);
140 return;
141 }
142
143 rt_kprintf("Machine Check Exception.\n");
144 rt_kprintf("Caused by (from msr): ");
145 rt_kprintf("regs %p ", regs);
146
147 val = get_esr();
148
149 if (val& ESR_IMCP) {
150 rt_kprintf("Instruction");
151 mtspr(ESR, val & ~ESR_IMCP);
152 } else {
153 rt_kprintf("Data");
154 }
155 rt_kprintf(" machine check.\n");
156
157 show_regs(regs);
158 print_backtrace((unsigned long *)regs->gpr[1]);
159 panic("machine check");
160 }
161
AlignmentException(struct pt_regs * regs)162 void AlignmentException(struct pt_regs *regs)
163 {
164 show_regs(regs);
165 print_backtrace((unsigned long *)regs->gpr[1]);
166 panic("Alignment Exception");
167 }
168
ProgramCheckException(struct pt_regs * regs)169 void ProgramCheckException(struct pt_regs *regs)
170 {
171 long esr_val;
172
173 show_regs(regs);
174
175 esr_val = get_esr();
176 if( esr_val & ESR_PIL )
177 rt_kprintf( "** Illegal Instruction **\n" );
178 else if( esr_val & ESR_PPR )
179 rt_kprintf( "** Privileged Instruction **\n" );
180 else if( esr_val & ESR_PTR )
181 rt_kprintf( "** Trap Instruction **\n" );
182
183 print_backtrace((unsigned long *)regs->gpr[1]);
184 panic("Program Check Exception");
185 }
186
DecrementerPITException(struct pt_regs * regs)187 void DecrementerPITException(struct pt_regs *regs)
188 {
189 /* reset PIT interrupt */
190 set_tsr(0x08000000);
191
192 /* increase a OS Tick */
193 rt_tick_increase();
194 }
195
UnknownException(struct pt_regs * regs)196 void UnknownException(struct pt_regs *regs)
197 {
198
199 rt_kprintf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
200 regs->nip, regs->msr, regs->trap);
201 _exception(0, regs);
202 }
203
DebugException(struct pt_regs * regs)204 void DebugException(struct pt_regs *regs)
205 {
206 rt_kprintf("Debugger trap at @ %lx @regs %lx\n", regs->nip, (rt_uint32_t)regs );
207 show_regs(regs);
208 }
209