mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
205 lines
4.9 KiB
205 lines
4.9 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* kgdb support for ARC |
|
* |
|
* Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) |
|
*/ |
|
|
|
#include <linux/kgdb.h> |
|
#include <linux/sched.h> |
|
#include <linux/sched/task_stack.h> |
|
#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; |
|
} |
|
|
|
void kgdb_trap(struct pt_regs *regs) |
|
{ |
|
/* 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. |
|
*/ |
|
if (regs->ecr_param == 3) |
|
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; |
|
} |
|
|
|
void kgdb_call_nmi_hook(void *ignored) |
|
{ |
|
/* Default implementation passes get_irq_regs() but we don't */ |
|
kgdb_nmicallback(raw_smp_processor_id(), NULL); |
|
} |
|
|
|
const 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 |
|
};
|
|
|