1 /*
2 * Port on Texas Instruments TMS320C6x architecture
3 *
4 * Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated
5 * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
6 *
7 * Updated for 2.6.34: Mark Salter <msalter@redhat.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13 #include <linux/ptrace.h>
14 #include <linux/tracehook.h>
15 #include <linux/regset.h>
16 #include <linux/elf.h>
17
18 #include <asm/cacheflush.h>
19
20 #define PT_REG_SIZE (sizeof(struct pt_regs))
21
22 /*
23 * Called by kernel/ptrace.c when detaching.
24 */
ptrace_disable(struct task_struct * child)25 void ptrace_disable(struct task_struct *child)
26 {
27 /* nothing to do */
28 }
29
30 /*
31 * Get a register number from live pt_regs for the specified task.
32 */
get_reg(struct task_struct * task,int regno)33 static inline long get_reg(struct task_struct *task, int regno)
34 {
35 long *addr = (long *)task_pt_regs(task);
36
37 if (regno == PT_TSR || regno == PT_CSR)
38 return 0;
39
40 return addr[regno];
41 }
42
43 /*
44 * Write contents of register REGNO in task TASK.
45 */
put_reg(struct task_struct * task,int regno,unsigned long data)46 static inline int put_reg(struct task_struct *task,
47 int regno,
48 unsigned long data)
49 {
50 unsigned long *addr = (unsigned long *)task_pt_regs(task);
51
52 if (regno != PT_TSR && regno != PT_CSR)
53 addr[regno] = data;
54
55 return 0;
56 }
57
58 /* regset get/set implementations */
59
gpr_get(struct task_struct * target,const struct user_regset * regset,unsigned int pos,unsigned int count,void * kbuf,void __user * ubuf)60 static int gpr_get(struct task_struct *target,
61 const struct user_regset *regset,
62 unsigned int pos, unsigned int count,
63 void *kbuf, void __user *ubuf)
64 {
65 struct pt_regs *regs = task_pt_regs(target);
66
67 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
68 regs,
69 0, sizeof(*regs));
70 }
71
72 enum c6x_regset {
73 REGSET_GPR,
74 };
75
76 static const struct user_regset c6x_regsets[] = {
77 [REGSET_GPR] = {
78 .core_note_type = NT_PRSTATUS,
79 .n = ELF_NGREG,
80 .size = sizeof(u32),
81 .align = sizeof(u32),
82 .get = gpr_get,
83 },
84 };
85
86 static const struct user_regset_view user_c6x_native_view = {
87 .name = "tic6x",
88 .e_machine = EM_TI_C6000,
89 .regsets = c6x_regsets,
90 .n = ARRAY_SIZE(c6x_regsets),
91 };
92
task_user_regset_view(struct task_struct * task)93 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
94 {
95 return &user_c6x_native_view;
96 }
97
98 /*
99 * Perform ptrace request
100 */
arch_ptrace(struct task_struct * child,long request,unsigned long addr,unsigned long data)101 long arch_ptrace(struct task_struct *child, long request,
102 unsigned long addr, unsigned long data)
103 {
104 int ret = 0;
105
106 switch (request) {
107 /*
108 * write the word at location addr.
109 */
110 case PTRACE_POKETEXT:
111 ret = generic_ptrace_pokedata(child, addr, data);
112 if (ret == 0 && request == PTRACE_POKETEXT)
113 flush_icache_range(addr, addr + 4);
114 break;
115 default:
116 ret = ptrace_request(child, request, addr, data);
117 break;
118 }
119
120 return ret;
121 }
122
123 /*
124 * handle tracing of system call entry
125 * - return the revised system call number or ULONG_MAX to cause ENOSYS
126 */
syscall_trace_entry(struct pt_regs * regs)127 asmlinkage unsigned long syscall_trace_entry(struct pt_regs *regs)
128 {
129 if (tracehook_report_syscall_entry(regs))
130 /* tracing decided this syscall should not happen, so
131 * We'll return a bogus call number to get an ENOSYS
132 * error, but leave the original number in
133 * regs->orig_a4
134 */
135 return ULONG_MAX;
136
137 return regs->b0;
138 }
139
140 /*
141 * handle tracing of system call exit
142 */
syscall_trace_exit(struct pt_regs * regs)143 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
144 {
145 tracehook_report_syscall_exit(regs, 0);
146 }
147