From de415ebdd62eced24823edc3d0d2805c8c3fac3b Mon Sep 17 00:00:00 2001 From: Alexandru Gagniuc Date: Wed, 15 Aug 2012 06:45:18 -0500 Subject: coreboot: Dump memory around problem area when encountering exception When we encounter an x86 exception, we print the problem address, dump the registers and die. This may not be sufficient information for debug. Also dump the memory around the problem instruction. This has proven useful in identifying memory issues, and DRAM burst reordering problems. Change-Id: I6411344e89f946e16d11217d7dbd73812c45d54c Signed-off-by: Alexandru Gagniuc Reviewed-on: http://review.coreboot.org/1454 Tested-by: build bot (Jenkins) Reviewed-by: Anton Kochkov --- src/arch/x86/lib/exception.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'src') diff --git a/src/arch/x86/lib/exception.c b/src/arch/x86/lib/exception.c index 4721bc8b16..97569493fd 100644 --- a/src/arch/x86/lib/exception.c +++ b/src/arch/x86/lib/exception.c @@ -475,6 +475,7 @@ void x86_exception(struct eregs *info) put_packet(out_buffer); } #else /* !CONFIG_GDB_STUB */ +#define MDUMP_SIZE 0x80 printk(BIOS_EMERG, "Unexpected Exception: %d @ %02x:%08x - Halting\n" "Code: %d eflags: %08x\n" @@ -484,6 +485,18 @@ void x86_exception(struct eregs *info) info->error_code, info->eflags, info->eax, info->ebx, info->ecx, info->edx, info->edi, info->esi, info->ebp, info->esp); + u8 *code = (u8*)((u32)info->eip - (MDUMP_SIZE >>1)); + /* Align to 8-byte boundary please, and print eight bytes per row. + * This is done to make DRAM burst timing/reordering errors more + * evident from the looking at the dump */ + code = (u8*)((u32)code & ~0x7); + int i; + for(i = 0; i < MDUMP_SIZE; i++) + { + if( (i & 0x07) == 0 ) + printk(BIOS_EMERG, "\n%.8x:\t", (int)code + i ); + printk(BIOS_EMERG, "%.2x ", code[i]); + } die(""); #endif } -- cgit v1.2.3