zephyr/arch/xtensa/core/xtensa_backtrace.c

137 lines
3.7 KiB
C

/*
* Copyright (c) 2020 Espressif Systems (Shanghai) Co., Ltd.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "xtensa/corebits.h"
#include "xtensa_backtrace.h"
#include <zephyr/sys/printk.h>
#if defined(CONFIG_SOC_SERIES_ESP32)
#include <esp_memory_utils.h>
#elif defined(CONFIG_SOC_FAMILY_INTEL_ADSP)
#include "debug_helpers.h"
#elif defined(CONFIG_SOC_XTENSA_DC233C)
#include "backtrace_helpers.h"
#endif
static int mask, cause;
static inline uint32_t xtensa_cpu_process_stack_pc(uint32_t pc)
{
if (pc & 0x80000000) {
/* Top two bits of a0 (return address) specify window increment.
* Overwrite to map to address space.
*/
if (cause != EXCCAUSE_INSTR_PROHIBITED) {
pc = (pc & 0x3fffffff) | mask;
} else {
pc = (pc & 0x3fffffff) | 0x40000000;
}
}
/* Minus 3 to get PC of previous instruction
* (i.e. instruction executed before return address)
*/
return pc - 3;
}
static inline bool xtensa_stack_ptr_is_sane(uint32_t sp)
{
#if defined(CONFIG_SOC_SERIES_ESP32)
return esp_stack_ptr_is_sane(sp);
#elif defined(CONFIG_SOC_FAMILY_INTEL_ADSP)
return intel_adsp_ptr_is_sane(sp);
#elif defined(CONFIG_SOC_XTENSA_DC233C)
return xtensa_dc233c_stack_ptr_is_sane(sp);
#else
#warning "xtensa_stack_ptr_is_sane is not defined for this platform"
#endif
}
static inline bool xtensa_ptr_executable(const void *p)
{
#if defined(CONFIG_SOC_SERIES_ESP32)
return esp_ptr_executable(p);
#elif defined(CONFIG_SOC_FAMILY_INTEL_ADSP)
return intel_adsp_ptr_executable(p);
#elif defined(CONFIG_SOC_XTENSA_DC233C)
return xtensa_dc233c_ptr_executable(p);
#else
#warning "xtensa_ptr_executable is not defined for this platform"
#endif
}
bool xtensa_backtrace_get_next_frame(struct xtensa_backtrace_frame_t *frame)
{
/* Use frame(i-1)'s BS area located below frame(i)'s
* sp to get frame(i-1)'s sp and frame(i-2)'s pc
*/
/* Base save area consists of 4 words under SP */
char *base_save = (char *)frame->sp;
frame->pc = frame->next_pc;
/* If next_pc = 0, indicates frame(i-1) is the last
* frame on the stack
*/
frame->next_pc = *((uint32_t *)(base_save - 16));
frame->sp = *((uint32_t *)(base_save - 12));
/* Return true if both sp and pc of frame(i-1) are sane,
* false otherwise
*/
return (xtensa_stack_ptr_is_sane(frame->sp) &&
xtensa_ptr_executable((void *)
xtensa_cpu_process_stack_pc(frame->pc)));
}
int xtensa_backtrace_print(int depth, int *interrupted_stack)
{
/* Check arguments */
if (depth <= 0) {
return -1;
}
/* Initialize stk_frame with first frame of stack */
struct xtensa_backtrace_frame_t stk_frame;
xtensa_backtrace_get_start(&(stk_frame.pc), &(stk_frame.sp),
&(stk_frame.next_pc), interrupted_stack);
__asm__ volatile("l32i a4, a3, 0");
__asm__ volatile("l32i a4, a4, 4");
__asm__ volatile("mov %0, a4" : "=r"(cause));
if (cause != EXCCAUSE_INSTR_PROHIBITED) {
mask = stk_frame.pc & 0xc0000000;
}
printk("\r\n\r\nBacktrace:");
printk("0x%08x:0x%08x ",
xtensa_cpu_process_stack_pc(stk_frame.pc),
stk_frame.sp);
/* Check if first frame is valid */
bool corrupted = !(xtensa_stack_ptr_is_sane(stk_frame.sp) &&
(xtensa_ptr_executable((void *)
xtensa_cpu_process_stack_pc(stk_frame.pc)) ||
/* Ignore the first corrupted PC in case of InstrFetchProhibited */
cause == EXCCAUSE_INSTR_PROHIBITED));
while (depth-- > 0 && stk_frame.next_pc != 0 && !corrupted) {
/* Get previous stack frame */
if (!xtensa_backtrace_get_next_frame(&stk_frame)) {
corrupted = true;
}
printk("0x%08x:0x%08x ", xtensa_cpu_process_stack_pc(stk_frame.pc), stk_frame.sp);
}
/* Print backtrace termination marker */
int ret = 0;
if (corrupted) {
printk(" |<-CORRUPTED");
ret = -1;
} else if (stk_frame.next_pc != 0) { /* Backtrace continues */
printk(" |<-CONTINUES");
}
printk("\r\n\r\n");
return ret;
}