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authorKyösti Mälkki <kyosti.malkki@gmail.com>2023-07-08 20:17:59 +0300
committerSubrata Banik <subratabanik@google.com>2023-07-08 18:54:24 +0000
commit0834b222c9fd9c3e2b054b81581d2d03ad9dfbc6 (patch)
treef47b80e27dc87a1072a3316d94507066ceda3965 /src/cpu/x86
parent3c1b7b485b6a9e2213d90cd4b904c2dacf79f666 (diff)
cpu/x86/lapic: Fix regression with X2APIC_LATE_WORKAROUND
This patch fixes the boot hang due to commit 053a45bcdb3ccf8 ("cpu/x86/lapic: Fix X2APIC_ONLY regression") on platform which selects X2APIC_LATE_WORKAROUND config. [EMERG] Switching from X2APIC to XAPIC mode is not implemented. Without this patch: Boot gets stuck inside at BS_WRITE_TABLES when enable_lapic() gets called after X2APIC mode has been enabled. The fix is to change enable_lapic() to track when late enablement for X2APIC mode happens with X2APIC_LATE_WORKAROUND. TEST=Able to build and boot google/rex to chromeos. Change-Id: I41e72380e9cfb59721d0df607ad875d7b6546974 Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/76384 Reviewed-by: Subrata Banik <subratabanik@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/cpu/x86')
-rw-r--r--src/cpu/x86/lapic/lapic.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/src/cpu/x86/lapic/lapic.c b/src/cpu/x86/lapic/lapic.c
index 24d2e37d47..8e0449a5fe 100644
--- a/src/cpu/x86/lapic/lapic.c
+++ b/src/cpu/x86/lapic/lapic.c
@@ -9,6 +9,8 @@
#include <smp/node.h>
#include <types.h>
+static bool quirk_x2apic_allowed;
+
void enable_lapic_mode(bool try_set_x2apic)
{
uintptr_t apic_base;
@@ -46,14 +48,18 @@ void enable_lapic_mode(bool try_set_x2apic)
die("Switching from X2APIC to XAPIC mode is not implemented.");
}
+ if (CONFIG(X2APIC_LATE_WORKAROUND) && use_x2apic)
+ quirk_x2apic_allowed = true;
}
void enable_lapic(void)
{
bool try_set_x2apic = true;
- if (CONFIG(XAPIC_ONLY) || CONFIG(X2APIC_LATE_WORKAROUND))
+ if (CONFIG(XAPIC_ONLY))
try_set_x2apic = false;
+ else if (CONFIG(X2APIC_LATE_WORKAROUND))
+ try_set_x2apic = quirk_x2apic_allowed;
enable_lapic_mode(try_set_x2apic);
}