1 | /* |
2 | * Microblaze KGDB support |
3 | * |
4 | * This file is subject to the terms and conditions of the GNU General Public |
5 | * License. See the file "COPYING" in the main directory of this archive |
6 | * for more details. |
7 | */ |
8 | |
9 | #include <linux/kgdb.h> |
10 | #include <linux/kdebug.h> |
11 | #include <linux/irq.h> |
12 | #include <linux/io.h> |
13 | #include <asm/cacheflush.h> |
14 | #include <asm/asm-offsets.h> |
15 | #include <asm/kgdb.h> |
16 | #include <asm/pvr.h> |
17 | |
18 | #define GDB_REG 0 |
19 | #define GDB_PC 32 |
20 | #define GDB_MSR 33 |
21 | #define GDB_EAR 34 |
22 | #define GDB_ESR 35 |
23 | #define GDB_FSR 36 |
24 | #define GDB_BTR 37 |
25 | #define GDB_PVR 38 |
26 | #define GDB_REDR 50 |
27 | #define GDB_RPID 51 |
28 | #define GDB_RZPR 52 |
29 | #define GDB_RTLBX 53 |
30 | #define GDB_RTLBSX 54 /* mfs can't read it */ |
31 | #define GDB_RTLBLO 55 |
32 | #define GDB_RTLBHI 56 |
33 | |
34 | /* keep pvr separately because it is unchangeable */ |
35 | static struct pvr_s pvr; |
36 | |
37 | void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) |
38 | { |
39 | unsigned int i; |
40 | unsigned long *pt_regb = (unsigned long *)regs; |
41 | int temp; |
42 | |
43 | /* registers r0 - r31, pc, msr, ear, esr, fsr + do not save pt_mode */ |
44 | for (i = 0; i < (sizeof(struct pt_regs) / 4) - 1; i++) |
45 | gdb_regs[i] = pt_regb[i]; |
46 | |
47 | /* Branch target register can't be changed */ |
48 | __asm__ __volatile__ ("mfs %0, rbtr;" : "=r" (temp) : ); |
49 | gdb_regs[GDB_BTR] = temp; |
50 | |
51 | /* pvr part - we have 11 pvr regs */ |
52 | for (i = 0; i < sizeof(struct pvr_s)/4; i++) |
53 | gdb_regs[GDB_PVR + i] = pvr.pvr[i]; |
54 | |
55 | /* read special registers - can't be changed */ |
56 | __asm__ __volatile__ ("mfs %0, redr;" : "=r" (temp) : ); |
57 | gdb_regs[GDB_REDR] = temp; |
58 | __asm__ __volatile__ ("mfs %0, rpid;" : "=r" (temp) : ); |
59 | gdb_regs[GDB_RPID] = temp; |
60 | __asm__ __volatile__ ("mfs %0, rzpr;" : "=r" (temp) : ); |
61 | gdb_regs[GDB_RZPR] = temp; |
62 | __asm__ __volatile__ ("mfs %0, rtlbx;" : "=r" (temp) : ); |
63 | gdb_regs[GDB_RTLBX] = temp; |
64 | __asm__ __volatile__ ("mfs %0, rtlblo;" : "=r" (temp) : ); |
65 | gdb_regs[GDB_RTLBLO] = temp; |
66 | __asm__ __volatile__ ("mfs %0, rtlbhi;" : "=r" (temp) : ); |
67 | gdb_regs[GDB_RTLBHI] = temp; |
68 | } |
69 | |
70 | void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) |
71 | { |
72 | unsigned int i; |
73 | unsigned long *pt_regb = (unsigned long *)regs; |
74 | |
75 | /* pt_regs and gdb_regs have the same 37 values. |
76 | * The rest of gdb_regs are unused and can't be changed. |
77 | * r0 register value can't be changed too. */ |
78 | for (i = 1; i < (sizeof(struct pt_regs) / 4) - 1; i++) |
79 | pt_regb[i] = gdb_regs[i]; |
80 | } |
81 | |
82 | asmlinkage void microblaze_kgdb_break(struct pt_regs *regs) |
83 | { |
84 | if (kgdb_handle_exception(ex_vector: 1, SIGTRAP, err_code: 0, regs) != 0) |
85 | return; |
86 | |
87 | /* Jump over the first arch_kgdb_breakpoint which is barrier to |
88 | * get kgdb work. The same solution is used for powerpc */ |
89 | if (*(u32 *) (regs->pc) == *(u32 *) (&arch_kgdb_ops.gdb_bpt_instr)) |
90 | regs->pc += BREAK_INSTR_SIZE; |
91 | } |
92 | |
93 | /* untested */ |
94 | void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) |
95 | { |
96 | unsigned int i; |
97 | unsigned long *pt_regb = (unsigned long *)(p->thread.regs); |
98 | |
99 | /* registers r0 - r31, pc, msr, ear, esr, fsr + do not save pt_mode */ |
100 | for (i = 0; i < (sizeof(struct pt_regs) / 4) - 1; i++) |
101 | gdb_regs[i] = pt_regb[i]; |
102 | |
103 | /* pvr part - we have 11 pvr regs */ |
104 | for (i = 0; i < sizeof(struct pvr_s)/4; i++) |
105 | gdb_regs[GDB_PVR + i] = pvr.pvr[i]; |
106 | } |
107 | |
108 | void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) |
109 | { |
110 | regs->pc = ip; |
111 | } |
112 | |
113 | int kgdb_arch_handle_exception(int vector, int signo, int err_code, |
114 | char *remcom_in_buffer, char *remcom_out_buffer, |
115 | struct pt_regs *regs) |
116 | { |
117 | char *ptr; |
118 | unsigned long address; |
119 | |
120 | switch (remcom_in_buffer[0]) { |
121 | case 'c': |
122 | /* handle the optional parameter */ |
123 | ptr = &remcom_in_buffer[1]; |
124 | if (kgdb_hex2long(ptr: &ptr, long_val: &address)) |
125 | regs->pc = address; |
126 | |
127 | return 0; |
128 | } |
129 | return -1; /* this means that we do not want to exit from the handler */ |
130 | } |
131 | |
132 | int kgdb_arch_init(void) |
133 | { |
134 | get_pvr(&pvr); /* Fill PVR structure */ |
135 | return 0; |
136 | } |
137 | |
138 | void kgdb_arch_exit(void) |
139 | { |
140 | /* Nothing to do */ |
141 | } |
142 | |
143 | /* |
144 | * Global data |
145 | */ |
146 | const struct kgdb_arch arch_kgdb_ops = { |
147 | #ifdef __MICROBLAZEEL__ |
148 | .gdb_bpt_instr = {0x18, 0x00, 0x0c, 0xba}, /* brki r16, 0x18 */ |
149 | #else |
150 | .gdb_bpt_instr = {0xba, 0x0c, 0x00, 0x18}, /* brki r16, 0x18 */ |
151 | #endif |
152 | }; |
153 | |