[PATCH v2 12/17] x86/cpu/intel: Replace Family 5 model checks with VFM ones

From: Sohil Mehta
Date: Tue Feb 11 2025 - 14:49:44 EST


Introduce names for some Family 5 models and convert some of the checks
to be VFM based.

Also, to keep the file sorted by family, move Family 5 to the top of the
header file.

Signed-off-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>

---

v2: Reorder the Family 5 models to be at the top of the file.

---
arch/x86/include/asm/intel-family.h | 9 ++++++---
arch/x86/kernel/cpu/intel.c | 11 +++++------
2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/intel-family.h b/arch/x86/include/asm/intel-family.h
index f509061b8c7e..9e6a13f03f0e 100644
--- a/arch/x86/include/asm/intel-family.h
+++ b/arch/x86/include/asm/intel-family.h
@@ -45,6 +45,12 @@
/* Wildcard match so X86_MATCH_VFM(ANY) works */
#define INTEL_ANY IFM(X86_FAMILY_ANY, X86_MODEL_ANY)

+/* Family 5 */
+#define INTEL_FAM5_START IFM(5, 0x00) /* Notational marker, also P5 A-step */
+#define INTEL_PENTIUM_75 IFM(5, 0x02) /* P54C */
+#define INTEL_PENTIUM_MMX IFM(5, 0x04) /* P55C */
+#define INTEL_QUARK_X1000 IFM(5, 0x09) /* Quark X1000 SoC */
+
/* Family 6 */
#define INTEL_PENTIUM_PRO IFM(6, 0x01)
#define INTEL_PENTIUM_II_KLAMATH IFM(6, 0x03)
@@ -181,9 +187,6 @@
#define INTEL_XEON_PHI_KNL IFM(6, 0x57) /* Knights Landing */
#define INTEL_XEON_PHI_KNM IFM(6, 0x85) /* Knights Mill */

-/* Family 5 */
-#define INTEL_QUARK_X1000 IFM(5, 0x09) /* Quark X1000 SoC */
-
/* Family 15 - NetBurst */
#define INTEL_P4_WILLAMETTE IFM(15, 0x01) /* Also Xeon Foster */
#define INTEL_P4_PRESCOTT IFM(15, 0x03)
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 507cb4c6d587..1b01ef4dfda2 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -375,9 +375,8 @@ static void intel_smp_check(struct cpuinfo_x86 *c)
/*
* Mask B, Pentium, but not Pentium MMX
*/
- if (c->x86 == 5 &&
- c->x86_stepping >= 1 && c->x86_stepping <= 4 &&
- c->x86_model <= 3) {
+ if (c->x86_vfm >= INTEL_FAM5_START && c->x86_vfm < INTEL_PENTIUM_MMX &&
+ c->x86_stepping >= 1 && c->x86_stepping <= 4) {
/*
* Remember we have B step Pentia with bugs
*/
@@ -404,7 +403,7 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
* The Quark is also family 5, but does not have the same bug.
*/
clear_cpu_bug(c, X86_BUG_F00F);
- if (c->x86 == 5 && c->x86_model < 9) {
+ if (c->x86_vfm >= INTEL_FAM5_START && c->x86_vfm < INTEL_QUARK_X1000) {
static int f00f_workaround_enabled;

set_cpu_bug(c, X86_BUG_F00F);
@@ -452,7 +451,7 @@ static void intel_workarounds(struct cpuinfo_x86 *c)
* integrated APIC (see 11AP erratum in "Pentium Processor
* Specification Update").
*/
- if (boot_cpu_has(X86_FEATURE_APIC) && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
+ if (boot_cpu_has(X86_FEATURE_APIC) && c->x86_vfm == INTEL_PENTIUM_75 &&
(c->x86_stepping < 0x6 || c->x86_stepping == 0xb))
set_cpu_bug(c, X86_BUG_11AP);

@@ -627,7 +626,7 @@ static unsigned int intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
* Intel Quark SoC X1000 contains a 4-way set associative
* 16K cache with a 16 byte cache line and 256 lines per tag
*/
- if ((c->x86 == 5) && (c->x86_model == 9))
+ if (c->x86_vfm == INTEL_QUARK_X1000)
size = 16;
return size;
}
--
2.43.0