[U-Boot] [PATCH v2 1/1] arm: print instructions pointed to by pc

[Heinrich Schuchardt]

If an exception occurs in a loaded image and the relocation offset is
unknown, it is helful to know the instructions pointed to by the
program counter. This patch adds the missing output.

A possible output is:
    *pc: fb de f7 e7 1e ff 2f e1 01 00 50 e3 f0 4d 2d e9 01 80 a0 e1

The output can be disassembled with
    xxd -pc -r - > a.out
    $(CROSS_COMPILE)objdump -D -marm -b binary a.out

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
v2
	print bytes not halfwords
---
 arch/arm/lib/interrupts.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/lib/interrupts.c b/arch/arm/lib/interrupts.c
index 28ba3f14f36..25489e34462 100644
--- a/arch/arm/lib/interrupts.c
+++ b/arch/arm/lib/interrupts.c
@@ -59,6 +59,9 @@ static void show_efi_loaded_images(struct pt_regs *regs)
 void show_regs (struct pt_regs *regs)
 {
 	unsigned long __maybe_unused flags;
+	/* The least significant bit chooses thumb, remove it. */
+	u8 *pc = (u8 *)(instruction_pointer(regs) & ~1);
+	int i;
 	const char __maybe_unused *processor_modes[] = {
 	"USER_26",	"FIQ_26",	"IRQ_26",	"SVC_26",
 	"UK4_26",	"UK5_26",	"UK6_26",	"UK7_26",
@@ -96,6 +99,10 @@ void show_regs (struct pt_regs *regs)
 		fast_interrupts_enabled (regs) ? "on" : "off",
 		processor_modes[processor_mode (regs)],
 		thumb_mode (regs) ? " (T)" : "");
+	printf("*pc:");
+	for (i = 0; i < 24; ++i)
+		printf(" %02x", pc[i]);
+	printf("\n");
 }
 
 /* fixup PC to point to the instruction leading to the exception */
-- 
2.14.2