2013-01-18 10:42:24 +01:00
|
|
|
/*
|
|
|
|
* kgdb support for ARC
|
|
|
|
*
|
|
|
|
* Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or modify
|
|
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
|
|
* published by the Free Software Foundation.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/kgdb.h>
|
2013-03-07 12:17:23 +01:00
|
|
|
#include <linux/sched.h>
|
2013-01-18 10:42:24 +01:00
|
|
|
#include <asm/disasm.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
|
|
|
|
|
|
static void to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs,
|
|
|
|
struct callee_regs *cregs)
|
|
|
|
{
|
|
|
|
int regno;
|
|
|
|
|
|
|
|
for (regno = 0; regno <= 26; regno++)
|
|
|
|
gdb_regs[_R0 + regno] = get_reg(regno, kernel_regs, cregs);
|
|
|
|
|
|
|
|
for (regno = 27; regno < GDB_MAX_REGS; regno++)
|
|
|
|
gdb_regs[regno] = 0;
|
|
|
|
|
|
|
|
gdb_regs[_FP] = kernel_regs->fp;
|
|
|
|
gdb_regs[__SP] = kernel_regs->sp;
|
|
|
|
gdb_regs[_BLINK] = kernel_regs->blink;
|
|
|
|
gdb_regs[_RET] = kernel_regs->ret;
|
|
|
|
gdb_regs[_STATUS32] = kernel_regs->status32;
|
|
|
|
gdb_regs[_LP_COUNT] = kernel_regs->lp_count;
|
|
|
|
gdb_regs[_LP_END] = kernel_regs->lp_end;
|
|
|
|
gdb_regs[_LP_START] = kernel_regs->lp_start;
|
|
|
|
gdb_regs[_BTA] = kernel_regs->bta;
|
|
|
|
gdb_regs[_STOP_PC] = kernel_regs->ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void from_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs,
|
|
|
|
struct callee_regs *cregs)
|
|
|
|
{
|
|
|
|
int regno;
|
|
|
|
|
|
|
|
for (regno = 0; regno <= 26; regno++)
|
|
|
|
set_reg(regno, gdb_regs[regno + _R0], kernel_regs, cregs);
|
|
|
|
|
|
|
|
kernel_regs->fp = gdb_regs[_FP];
|
|
|
|
kernel_regs->sp = gdb_regs[__SP];
|
|
|
|
kernel_regs->blink = gdb_regs[_BLINK];
|
|
|
|
kernel_regs->ret = gdb_regs[_RET];
|
|
|
|
kernel_regs->status32 = gdb_regs[_STATUS32];
|
|
|
|
kernel_regs->lp_count = gdb_regs[_LP_COUNT];
|
|
|
|
kernel_regs->lp_end = gdb_regs[_LP_END];
|
|
|
|
kernel_regs->lp_start = gdb_regs[_LP_START];
|
|
|
|
kernel_regs->bta = gdb_regs[_BTA];
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
|
|
|
|
{
|
|
|
|
to_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *)
|
|
|
|
current->thread.callee_reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
|
|
|
|
{
|
|
|
|
from_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *)
|
|
|
|
current->thread.callee_reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs,
|
|
|
|
struct task_struct *task)
|
|
|
|
{
|
|
|
|
if (task)
|
|
|
|
to_gdb_regs(gdb_regs, task_pt_regs(task),
|
|
|
|
(struct callee_regs *) task->thread.callee_reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
struct single_step_data_t {
|
|
|
|
uint16_t opcode[2];
|
|
|
|
unsigned long address[2];
|
|
|
|
int is_branch;
|
|
|
|
int armed;
|
|
|
|
} single_step_data;
|
|
|
|
|
|
|
|
static void undo_single_step(struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
if (single_step_data.armed) {
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < (single_step_data.is_branch ? 2 : 1); i++) {
|
|
|
|
memcpy((void *) single_step_data.address[i],
|
|
|
|
&single_step_data.opcode[i],
|
|
|
|
BREAK_INSTR_SIZE);
|
|
|
|
|
|
|
|
flush_icache_range(single_step_data.address[i],
|
|
|
|
single_step_data.address[i] +
|
|
|
|
BREAK_INSTR_SIZE);
|
|
|
|
}
|
|
|
|
single_step_data.armed = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void place_trap(unsigned long address, void *save)
|
|
|
|
{
|
|
|
|
memcpy(save, (void *) address, BREAK_INSTR_SIZE);
|
|
|
|
memcpy((void *) address, &arch_kgdb_ops.gdb_bpt_instr,
|
|
|
|
BREAK_INSTR_SIZE);
|
|
|
|
flush_icache_range(address, address + BREAK_INSTR_SIZE);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void do_single_step(struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
single_step_data.is_branch = disasm_next_pc((unsigned long)
|
|
|
|
regs->ret, regs, (struct callee_regs *)
|
|
|
|
current->thread.callee_reg,
|
|
|
|
&single_step_data.address[0],
|
|
|
|
&single_step_data.address[1]);
|
|
|
|
|
|
|
|
place_trap(single_step_data.address[0], &single_step_data.opcode[0]);
|
|
|
|
|
|
|
|
if (single_step_data.is_branch) {
|
|
|
|
place_trap(single_step_data.address[1],
|
|
|
|
&single_step_data.opcode[1]);
|
|
|
|
}
|
|
|
|
|
|
|
|
single_step_data.armed++;
|
|
|
|
}
|
|
|
|
|
|
|
|
int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
|
|
|
|
char *remcomInBuffer, char *remcomOutBuffer,
|
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
unsigned long addr;
|
|
|
|
char *ptr;
|
|
|
|
|
|
|
|
undo_single_step(regs);
|
|
|
|
|
|
|
|
switch (remcomInBuffer[0]) {
|
|
|
|
case 's':
|
|
|
|
case 'c':
|
|
|
|
ptr = &remcomInBuffer[1];
|
|
|
|
if (kgdb_hex2long(&ptr, &addr))
|
|
|
|
regs->ret = addr;
|
|
|
|
|
|
|
|
case 'D':
|
|
|
|
case 'k':
|
|
|
|
atomic_set(&kgdb_cpu_doing_single_step, -1);
|
|
|
|
|
|
|
|
if (remcomInBuffer[0] == 's') {
|
|
|
|
do_single_step(regs);
|
|
|
|
atomic_set(&kgdb_cpu_doing_single_step,
|
|
|
|
smp_processor_id());
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
int kgdb_arch_init(void)
|
|
|
|
{
|
|
|
|
single_step_data.armed = 0;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2013-06-12 11:43:40 +02:00
|
|
|
void kgdb_trap(struct pt_regs *regs)
|
2013-01-18 10:42:24 +01:00
|
|
|
{
|
|
|
|
/* trap_s 3 is used for breakpoints that overwrite existing
|
|
|
|
* instructions, while trap_s 4 is used for compiled breakpoints.
|
|
|
|
*
|
|
|
|
* with trap_s 3 breakpoints the original instruction needs to be
|
|
|
|
* restored and continuation needs to start at the location of the
|
|
|
|
* breakpoint.
|
|
|
|
*
|
|
|
|
* with trap_s 4 (compiled) breakpoints, continuation needs to
|
|
|
|
* start after the breakpoint.
|
|
|
|
*/
|
2013-06-11 15:26:54 +02:00
|
|
|
if (regs->ecr_param == 3)
|
2013-01-18 10:42:24 +01:00
|
|
|
instruction_pointer(regs) -= BREAK_INSTR_SIZE;
|
|
|
|
|
|
|
|
kgdb_handle_exception(1, SIGTRAP, 0, regs);
|
|
|
|
}
|
|
|
|
|
|
|
|
void kgdb_arch_exit(void)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
|
|
|
void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
|
|
|
|
{
|
|
|
|
instruction_pointer(regs) = ip;
|
|
|
|
}
|
|
|
|
|
2013-10-24 05:50:09 +02:00
|
|
|
static void kgdb_call_nmi_hook(void *ignored)
|
|
|
|
{
|
|
|
|
kgdb_nmicallback(raw_smp_processor_id(), NULL);
|
|
|
|
}
|
|
|
|
|
|
|
|
void kgdb_roundup_cpus(unsigned long flags)
|
|
|
|
{
|
|
|
|
local_irq_enable();
|
|
|
|
smp_call_function(kgdb_call_nmi_hook, NULL, 0);
|
|
|
|
local_irq_disable();
|
|
|
|
}
|
|
|
|
|
2013-01-18 10:42:24 +01:00
|
|
|
struct kgdb_arch arch_kgdb_ops = {
|
|
|
|
/* breakpoint instruction: TRAP_S 0x3 */
|
|
|
|
#ifdef CONFIG_CPU_BIG_ENDIAN
|
|
|
|
.gdb_bpt_instr = {0x78, 0x7e},
|
|
|
|
#else
|
|
|
|
.gdb_bpt_instr = {0x7e, 0x78},
|
|
|
|
#endif
|
|
|
|
};
|