esp-idf/components/esp_gdbstub/xtensa/gdbstub_xtensa.c
Sachin Parekh 6618e0c31d gdb: Modify PC in case of invalid PC
Signed-off-by: Sachin Parekh <sachin.parekh@espressif.com>
2020-07-31 07:40:12 +00:00

133 lines
4.1 KiB
C

// Copyright 2015-2019 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <string.h>
#include "esp_gdbstub.h"
#include "esp_gdbstub_common.h"
#include "soc/cpu.h"
#include "soc/soc_memory_layout.h"
#include "sdkconfig.h"
#if !XCHAL_HAVE_WINDOWED
#warning "gdbstub_xtensa: revisit the implementation for Call0 ABI"
#endif
extern int _invalid_pc_placeholder;
static void init_regfile(esp_gdbstub_gdb_regfile_t *dst)
{
memset(dst, 0, sizeof(*dst));
}
static void update_regfile_common(esp_gdbstub_gdb_regfile_t *dst)
{
if (dst->a[0] & 0x8000000U) {
dst->a[0] = (dst->a[0] & 0x3fffffffU) | 0x40000000U;
}
if (!esp_stack_ptr_is_sane(dst->a[1])) {
dst->a[1] = 0xDEADBEEF;
}
dst->windowbase = 0;
dst->windowstart = 0x1;
RSR(CONFIGID0, dst->configid0);
RSR(CONFIGID1, dst->configid1);
}
void esp_gdbstub_frame_to_regfile(const esp_gdbstub_frame_t *frame, esp_gdbstub_gdb_regfile_t *dst)
{
init_regfile(dst);
const uint32_t *a_regs = (const uint32_t *) &frame->a0;
if (!(esp_ptr_executable((void *)((frame->pc & 0x3fffffffU) | 0x40000000U)) && (frame->pc & 0xC0000000U))) {
/* Xtensa ABI sets the 2 MSBs of the PC according to the windowed call size
* Incase the PC is invalid, GDB will fail to translate addresses to function names
* Hence replacing the PC to a placeholder address in case of invalid PC
*/
dst->pc = (uint32_t)&_invalid_pc_placeholder;
} else {
dst->pc = (frame->pc & 0x3fffffffU) | 0x40000000U;
}
for (int i = 0; i < 16; i++) {
dst->a[i] = a_regs[i];
}
for (int i = 16; i < 64; i++) {
dst->a[i] = 0xDEADBEEF;
}
#if XCHAL_HAVE_LOOPS
dst->lbeg = frame->lbeg;
dst->lend = frame->lend;
dst->lcount = frame->lcount;
#endif
dst->ps = (frame->ps & PS_UM) ? (frame->ps & ~PS_EXCM) : frame->ps;
dst->sar = frame->sar;
update_regfile_common(dst);
}
#ifdef CONFIG_ESP_GDBSTUB_SUPPORT_TASKS
static void solicited_frame_to_regfile(const XtSolFrame *frame, esp_gdbstub_gdb_regfile_t *dst)
{
init_regfile(dst);
const uint32_t *a_regs = (const uint32_t *) &frame->a0;
if (!(esp_ptr_executable((void *)((frame->pc & 0x3fffffffU) | 0x40000000U)) && (frame->pc & 0xC0000000U))) {
dst->pc = (uint32_t)&_invalid_pc_placeholder;
} else {
dst->pc = (frame->pc & 0x3fffffffU) | 0x40000000U;
}
/* only 4 registers saved in the solicited frame */
for (int i = 0; i < 4; i++) {
dst->a[i] = a_regs[i];
}
for (int i = 4; i < 64; i++) {
dst->a[i] = 0xDEADBEEF;
}
dst->ps = (frame->ps & PS_UM) ? (frame->ps & ~PS_EXCM) : frame->ps;
update_regfile_common(dst);
}
/* Represents FreeRTOS TCB structure */
typedef struct {
uint8_t *top_of_stack;
/* Other members aren't needed */
} dummy_tcb_t;
void esp_gdbstub_tcb_to_regfile(TaskHandle_t tcb, esp_gdbstub_gdb_regfile_t *dst)
{
const dummy_tcb_t *dummy_tcb = (const dummy_tcb_t *) tcb;
const XtExcFrame *frame = (XtExcFrame *) dummy_tcb->top_of_stack;
if (frame->exit != 0) {
esp_gdbstub_frame_to_regfile(frame, dst);
} else {
const XtSolFrame *taskFrame = (const XtSolFrame *) dummy_tcb->top_of_stack;
solicited_frame_to_regfile(taskFrame, dst);
}
}
#endif // CONFIG_ESP_GDBSTUB_SUPPORT_TASKS
int esp_gdbstub_get_signal(const esp_gdbstub_frame_t *frame)
{
const char exccause_to_signal[] = {4, 31, 11, 11, 2, 6, 8, 0, 6, 7, 0, 0, 7, 7, 7, 7};
if (frame->exccause > sizeof(exccause_to_signal)) {
return 11;
}
return (int) exccause_to_signal[frame->exccause];
}