xtensa: fix getting exccause during backtrace (b696257e) · Commits · Wenxi XU / zephyr

We have frame pointer struct and BSA struct to extract the exception cause (exccause). There is no need to resort to custom assembly to do that. Besides, given that the BSA is different between different Xtensa cores, there is no guarantee it is at the same place as what the assembly assumes. So just do that without assembly. Signed-off-by:

Daniel Leung <daniel.leung@intel.com>

arch/xtensa/core/xtensa_backtrace.c

+10 −3

Original line number	Diff line number	Diff line
		@@ -14,6 +14,9 @@
		#elif defined(CONFIG_SOC_XTENSA_DC233C)
		#include "backtrace_helpers.h"
		#endif

		#include <xtensa_asm2_context.h>

		static int mask, cause;

		static inline uint32_t xtensa_cpu_process_stack_pc(uint32_t pc)
		@@ -91,14 +94,18 @@ int xtensa_backtrace_print(int depth, int *interrupted_stack)
		return -1;
		}

		_xtensa_irq_stack_frame_raw_t frame = (void )interrupted_stack;
		_xtensa_irq_bsa_t *bsa;

		bsa = frame->ptr_to_bsa;
		cause = bsa->exccause;

		/* 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;
		}

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