[PATCH 07/11] x86/tsc: Move away from TSC leaf magic numbers

Dave Hansen
2024-11-20T19:53:37Z

From: Dave Hansen <dave.hansen@linux.intel.com>

The TSC code has a bunch of hard-coded references to leaf 0x15. Change
them over to the symbolic name. Also zap the 'ART_CPUID_LEAF' definition.
It was a duplicate of 'CPUID_TSC_LEAF'.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
---

b/arch/x86/kernel/tsc.c | 11 +++++------
b/drivers/platform/x86/intel/pmc/core.c | 7 ++++---
2 files changed, 9 insertions(+), 9 deletions(-)

diff -puN arch/x86/kernel/tsc.c~tsc-leaf-checks-2 arch/x86/kernel/tsc.c
--- a/arch/x86/kernel/tsc.c~tsc-leaf-checks-2 2024-11-20 11:44:18.789710767 -0800
+++ b/arch/x86/kernel/tsc.c 2024-11-20 11:44:18.793710919 -0800
@@ -16,6 +16,7 @@
#include <linux/static_key.h>
#include <linux/static_call.h>

+#include <asm/cpuid.h>
#include <asm/hpet.h>
#include <asm/timer.h>
#include <asm/vgtod.h>
@@ -664,13 +665,13 @@ unsigned long native_calibrate_tsc(void)
if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
return 0;

- if (boot_cpu_data.cpuid_level < 0x15)
+ if (boot_cpu_data.cpuid_level < CPUID_TSC_LEAF)
return 0;

eax_denominator = ebx_numerator = ecx_hz = edx = 0;

/* CPUID 15H TSC/Crystal ratio, plus optionally Crystal Hz */
- cpuid(0x15, &eax_denominator, &ebx_numerator, &ecx_hz, &edx);
+ cpuid(CPUID_TSC_LEAF, &eax_denominator, &ebx_numerator, &ecx_hz, &edx);

if (ebx_numerator == 0 || eax_denominator == 0)
return 0;
@@ -1066,10 +1067,8 @@ core_initcall(cpufreq_register_tsc_scali

#endif /* CONFIG_CPU_FREQ */

-#define ART_CPUID_LEAF (0x15)
#define ART_MIN_DENOMINATOR (1)

-
/*
* If ART is present detect the numerator:denominator to convert to TSC
*/
@@ -1077,7 +1076,7 @@ static void __init detect_art(void)
{
unsigned int unused;

- if (boot_cpu_data.cpuid_level < ART_CPUID_LEAF)
+ if (boot_cpu_data.cpuid_level < CPUID_TSC_LEAF)
return;

/*
@@ -1090,7 +1089,7 @@ static void __init detect_art(void)
tsc_async_resets)
return;

- cpuid(ART_CPUID_LEAF, &art_base_clk.denominator,
+ cpuid(CPUID_TSC_LEAF, &art_base_clk.denominator,
&art_base_clk.numerator, &art_base_clk.freq_khz, &unused);

art_base_clk.freq_khz /= KHZ;
diff -puN drivers/platform/x86/intel/pmc/core.c~tsc-leaf-checks-2 drivers/platform/x86/intel/pmc/core.c
--- a/drivers/platform/x86/intel/pmc/core.c~tsc-leaf-checks-2 2024-11-20 11:44:18.793710919 -0800
+++ b/drivers/platform/x86/intel/pmc/core.c 2024-11-20 11:44:18.793710919 -0800
@@ -22,6 +22,7 @@
#include <linux/suspend.h>
#include <linux/units.h>

+#include <asm/cpuid.h>
#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
#include <asm/msr.h>
@@ -935,13 +936,13 @@ static unsigned int pmc_core_get_crystal
{
unsigned int eax_denominator, ebx_numerator, ecx_hz, edx;

- if (boot_cpu_data.cpuid_level < 0x15)
+ if (boot_cpu_data.cpuid_level < CPUID_TSC_LEAF)
return 0;

eax_denominator = ebx_numerator = ecx_hz = edx = 0;

- /* CPUID 15H TSC/Crystal ratio, plus optionally Crystal Hz */
- cpuid(0x15, &eax_denominator, &ebx_numerator, &ecx_hz, &edx);
+ /* TSC/Crystal ratio, plus optionally Crystal Hz */
+ cpuid(CPUID_TSC_LEAF, &eax_denominator, &ebx_numerator, &ecx_hz, &edx);

if (ebx_numerator == 0 || eax_denominator == 0)
return 0;
_