Furquan Shaikh has uploaded this change for review. ( https://review.coreboot.org/24965
Change subject: cpu/x86/mp_init: Increase AP check-in timeout to 1second ......................................................................
cpu/x86/mp_init: Increase AP check-in timeout to 1second
Currently, the AP check-in timeout in bsp_do_flight_plan is set to 100ms. However, as the number of APs increases, contention could increase especially for resource like UART. This led to MP record timeout issues on KBL platform with 7 APs and serial-console enabled BIOS image.
This change increases the timeout value to 1 second to be on the safer side and let APs check-in before continuing boot.
BUG=b:74085891 TEST=Verified that MP record timeout is not observed anymore on Nami.
Change-Id: I979c11a10e6888aef0f71b5632ea803a67bbb0ff Signed-off-by: Furquan Shaikh furquan@google.com --- M src/cpu/x86/mp_init.c 1 file changed, 6 insertions(+), 1 deletion(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/65/24965/1
diff --git a/src/cpu/x86/mp_init.c b/src/cpu/x86/mp_init.c index 92eb722..06e30b6 100644 --- a/src/cpu/x86/mp_init.c +++ b/src/cpu/x86/mp_init.c @@ -539,7 +539,12 @@ { int i; int ret = 0; - const int timeout_us = 100000; + /* + * Set timeout to wait for APs to a huge value (=1 second) since it + * could take a longer time for APs to check-in as the number of APs + * increases (contention for resources like UART also increases). + */ + const int timeout_us = 1000000; const int step_us = 100; int num_aps = mp_params->num_cpus - 1;