summaryrefslogtreecommitdiff
path: root/src/arch/x86
diff options
context:
space:
mode:
authorMike Loptien <mike.loptien@se-eng.com>2014-06-11 14:20:48 -0600
committerMike Loptien <mike.loptien@se-eng.com>2014-06-16 18:14:35 +0200
commitd0167d3ae268e3fcdef5c02e381b47dbb04ab1a4 (patch)
tree265882f5cd1336d324a487d022ed6011e5404506 /src/arch/x86
parent915973406544d1d6a60a539ad9fb8a33c3caf2c9 (diff)
MP Spec: Correct the Virtual Wire assignment
Virtual Wire mode is set by writing 0 to the the MPTable Feature2 bit field 'IMCR'. The virtualwire variable was initially defined as writing a 1 to this bit field which would actually set PIC mode instead of Virtual Wire mode. However, nearly every mainboard called the MPTables with virtualwire = 0, which actually had the effect of setting Virtual Wire mode. I am correcting the definition but leaving the call to write the MPTables with virtualwire = 0, which is how most mainboards are already setting the tables up. See the MP Spec table 4-1 for more details: Bit 7: IMCRP. When the IMCR presence bit is set, the IMCR is present and PIC Mode is implemented; otherwise, Virtual Wire Mode is implemented. http://download.intel.com/design/archives/processors/pro/docs/24201606.pdf Change-Id: I039d88134aabd55166c2b68aa842bacbfcc0f42b Signed-off-by: Mike Loptien <mike.loptien@se-eng.com> Reviewed-on: http://review.coreboot.org/5977 Tested-by: build bot (Jenkins) Reviewed-by: Marc Jones <marc.jones@se-eng.com> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Diffstat (limited to 'src/arch/x86')
-rw-r--r--src/arch/x86/boot/mpspec.c2
-rw-r--r--src/arch/x86/include/arch/smp/mpspec.h4
2 files changed, 3 insertions, 3 deletions
diff --git a/src/arch/x86/boot/mpspec.c b/src/arch/x86/boot/mpspec.c
index e66535a89e..cd2b142a25 100644
--- a/src/arch/x86/boot/mpspec.c
+++ b/src/arch/x86/boot/mpspec.c
@@ -89,7 +89,7 @@ static void *smp_write_floating_table_physaddr(unsigned long addr, unsigned long
mf->mpf_specification = 4;
mf->mpf_checksum = 0;
mf->mpf_feature1 = 0;
- mf->mpf_feature2 = virtualwire?MP_FEATURE_VIRTUALWIRE:0;
+ mf->mpf_feature2 = virtualwire?MP_FEATURE_PIC:MP_FEATURE_VIRTUALWIRE;
mf->mpf_feature3 = 0;
mf->mpf_feature4 = 0;
mf->mpf_feature5 = 0;
diff --git a/src/arch/x86/include/arch/smp/mpspec.h b/src/arch/x86/include/arch/smp/mpspec.h
index fe3ce68011..725718ac25 100644
--- a/src/arch/x86/include/arch/smp/mpspec.h
+++ b/src/arch/x86/include/arch/smp/mpspec.h
@@ -52,8 +52,8 @@ struct intel_mp_floating
unsigned char mpf_checksum; /* Checksum (makes sum 0) */
unsigned char mpf_feature1; /* Standard or configuration ? */
unsigned char mpf_feature2; /* Bit7 set for IMCR|PIC */
-#define MP_FEATURE_VIRTUALWIRE (1 << 7)
-#define MP_FEATURE_PIC (0 << 7)
+#define MP_FEATURE_VIRTUALWIRE (0 << 7)
+#define MP_FEATURE_PIC (1 << 7)
unsigned char mpf_feature3; /* Unused (0) */
unsigned char mpf_feature4; /* Unused (0) */
unsigned char mpf_feature5; /* Unused (0) */