From 87c6097c8f3ec812101f302ce98d0e6a53c25bab Mon Sep 17 00:00:00 2001 From: Alexandru Gagniuc Date: Mon, 16 May 2016 14:22:00 -0700 Subject: [PATCH] arch/x86: Include timestamp.c in all stages timestamp.c was not included in bootblock and postcar. This means that these two stages would use the weak implementation in lib/timestamp.c instead of the arch-specific implementation based on rdtsc. This resulted in using timer_monotonic_get() which resets the timestamps from 0. timer_monotonic_get() only provides per-stage incrementing semantics on x86 because lapic implementation has counting down values. A globally incrementing counter like rdtsc provides the semantics like every other non-x86. On the test configuration, the weak implementation of timestamp_get() returned zero, resulting in wrong timestamps coming from the bootblock, while romstage and ramstage used the arch implementation and returned correct timestamps. This is a great example of why weak functions are dangerous, and how easy it is to miss subtle yet strong interactions between subsystems and the coreboot buildsystem. Change-Id: I656f9bd58a6fc179d9dbbc496c5b684ea9288eb5 Signed-off-by: Alexandru Gagniuc Reviewed-on: https://review.coreboot.org/14860 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin --- src/arch/x86/Makefile.inc | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/arch/x86/Makefile.inc b/src/arch/x86/Makefile.inc index a363430cad..c27bb1a994 100644 --- a/src/arch/x86/Makefile.inc +++ b/src/arch/x86/Makefile.inc @@ -97,6 +97,7 @@ ifeq ($(CONFIG_ARCH_BOOTBLOCK_X86_32)$(CONFIG_ARCH_BOOTBLOCK_X86_64),y) bootblock-y += boot.c bootblock-y += memcpy.c bootblock-y += memset.c +bootblock-$(CONFIG_COLLECT_TIMESTAMPS) += timestamp.c bootblock-$(CONFIG_X86_TOP4G_BOOTMEDIA_MAP) += mmap_boot.c bootblock-y += id.S @@ -394,6 +395,7 @@ postcar-y += memset.c postcar-y += memcpy.c postcar-y += memmove.c postcar-y += memlayout.ld +postcar-$(CONFIG_COLLECT_TIMESTAMPS) += timestamp.c postcar-$(CONFIG_X86_TOP4G_BOOTMEDIA_MAP) += mmap_boot.c $(objcbfs)/postcar.debug: $$(postcar-objs)