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x86/tsc: Move away from TSC leaf magic numbers
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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>
Link: https://lore.kernel.org/all/20241213205034.B79D6224%40davehans-spike.ostc.intel.com
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Dave Hansen committed Dec 18, 2024
1 parent a86740a commit 030c15b
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Showing 2 changed files with 9 additions and 9 deletions.
11 changes: 5 additions & 6 deletions arch/x86/kernel/tsc.c
Original file line number Diff line number Diff line change
Expand Up @@ -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>
Expand Down Expand Up @@ -665,13 +666,13 @@ 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;
Expand Down Expand Up @@ -1067,18 +1068,16 @@ core_initcall(cpufreq_register_tsc_scaling);

#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
*/
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;

/*
Expand All @@ -1091,7 +1090,7 @@ 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;
Expand Down
7 changes: 4 additions & 3 deletions drivers/platform/x86/intel/pmc/core.c
Original file line number Diff line number Diff line change
Expand Up @@ -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>
Expand Down Expand Up @@ -935,13 +936,13 @@ static unsigned int pmc_core_get_crystal_freq(void)
{
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;
Expand Down

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