[PATCH v6 15/51] x86/tsc: Kill off x86_platform_ops.calibrate_{cpu,tsc}() hooks

Now that getting the CPU and/or TSC frequencies from the hypervisor uses
dedicated hooks, drop x86_platform_ops.calibrate_{cpu,tsc}() and instead
directly invoke the correct helper at each phase of (re)calibration.  In
addition to eliminating unnecessary code, this makes it a bit more obvious
when the "late" path invokes pit_hpet_ptimer_calibrate_cpu() instead of
x86_platform_ops.calibrate_cpu().

No functional change intended.

Signed-off-by: Sean Christopherson <[email protected]>
---
 arch/x86/include/asm/tsc.h      |  2 --
 arch/x86/include/asm/x86_init.h |  4 ----
 arch/x86/kernel/tsc.c           | 28 ++++++++++++----------------
 arch/x86/kernel/x86_init.c      |  2 --
 4 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index b6b86e24e1bf..c09ec485abcd 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -95,8 +95,6 @@ extern void mark_tsc_unstable(char *reason);
 extern int unsynchronized_tsc(void);
 extern int check_tsc_unstable(void);
 extern void mark_tsc_async_resets(char *reason);
-extern unsigned long native_calibrate_cpu_early(void);
-extern unsigned long native_calibrate_tsc(void);
 extern unsigned long long native_sched_clock_from_tsc(u64 tsc);
 
 extern int tsc_clocksource_reliable;
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 0c89bf40f507..e879e6e83428 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -295,8 +295,6 @@ struct x86_hyper_runtime {
 
 /**
  * struct x86_platform_ops - platform specific runtime functions
- * @calibrate_cpu:		calibrate CPU
- * @calibrate_tsc:		calibrate TSC, if different from CPU
  * @get_wallclock:		get time from HW clock like RTC etc.
  * @set_wallclock:		set time back to HW clock
  * @iommu_shutdown:		set by an IOMMU driver for shutdown if necessary
@@ -320,8 +318,6 @@ struct x86_hyper_runtime {
  * @guest:			guest incarnations callbacks
  */
 struct x86_platform_ops {
-	unsigned long (*calibrate_cpu)(void);
-	unsigned long (*calibrate_tsc)(void);
 	void (*get_wallclock)(struct timespec64 *ts);
 	int (*set_wallclock)(const struct timespec64 *ts);
 	void (*iommu_shutdown)(void);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index f42872c9ae99..1d41ef1db27c 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -672,7 +672,7 @@ int cpuid_get_tsc_info(struct cpuid_tsc_info *info)
  * native_calibrate_tsc - determine TSC frequency
  * Determine TSC frequency via CPUID, else return 0.
  */
-unsigned long native_calibrate_tsc(void)
+static unsigned long native_calibrate_tsc(void)
 {
 	struct cpuid_tsc_info info;
 
@@ -904,7 +904,7 @@ static unsigned long pit_hpet_ptimer_calibrate_cpu(void)
 /**
  * native_calibrate_cpu_early - can calibrate the cpu early in boot
  */
-unsigned long native_calibrate_cpu_early(void)
+static unsigned long native_calibrate_cpu_early(void)
 {
 	unsigned long flags, fast_calibrate = cpu_khz_from_cpuid();
 
@@ -918,7 +918,7 @@ unsigned long native_calibrate_cpu_early(void)
 	return fast_calibrate;
 }
 
-
+#ifndef CONFIG_SMP
 /**
  * native_calibrate_cpu - calibrate the cpu
  */
@@ -931,6 +931,7 @@ static unsigned long native_calibrate_cpu(void)
 
 	return tsc_freq;
 }
+#endif
 
 void recalibrate_cpu_khz(void)
 {
@@ -943,8 +944,8 @@ void recalibrate_cpu_khz(void)
 	if (WARN_ON_ONCE(cpu_feature_enabled(X86_FEATURE_TSC_KNOWN_FREQ)))
 		return;
 
-	cpu_khz = x86_platform.calibrate_cpu();
-	tsc_khz = x86_platform.calibrate_tsc();
+	cpu_khz = native_calibrate_cpu();
+	tsc_khz = native_calibrate_tsc();
 	if (tsc_khz == 0)
 		tsc_khz = cpu_khz;
 	else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz)
@@ -1458,17 +1459,19 @@ static bool __init determine_cpu_tsc_frequencies(bool early,
 	WARN_ON(cpu_khz || tsc_khz);
 
 	if (early) {
+		/*
+		 * Early CPU calibration can only use methods that are available
+		 * early in boot (obviously).
+		 */
 		if (known_cpu_khz)
 			cpu_khz = known_cpu_khz;
 		else
-			cpu_khz = x86_platform.calibrate_cpu();
+			cpu_khz = native_calibrate_cpu_early();
 		if (known_tsc_khz)
 			tsc_khz = known_tsc_khz;
 		else
-			tsc_khz = x86_platform.calibrate_tsc();
+			tsc_khz = native_calibrate_tsc();
 	} else {
-		/* We should not be here with non-native cpu calibration */
-		WARN_ON(x86_platform.calibrate_cpu != native_calibrate_cpu);
 		cpu_khz = pit_hpet_ptimer_calibrate_cpu();
 	}
 
@@ -1571,13 +1574,6 @@ void __init tsc_init(void)
 		return;
 	}
 
-	/*
-	 * native_calibrate_cpu_early can only calibrate using methods that are
-	 * available early in boot.
-	 */
-	if (x86_platform.calibrate_cpu == native_calibrate_cpu_early)
-		x86_platform.calibrate_cpu = native_calibrate_cpu;
-
 	if (!tsc_khz) {
 		/* We failed to determine frequencies earlier, try again */
 		if (!determine_cpu_tsc_frequencies(false, 0, 0)) {
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index 252c5827d063..b7a48e622f48 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -147,8 +147,6 @@ static void enc_kexec_finish_noop(void) {}
 static bool is_private_mmio_noop(u64 addr) {return false; }
 
 struct x86_platform_ops x86_platform __ro_after_init = {
-	.calibrate_cpu			= native_calibrate_cpu_early,
-	.calibrate_tsc			= native_calibrate_tsc,
 	.get_wallclock			= mach_get_cmos_time,
 	.set_wallclock			= mach_set_cmos_time,
 	.iommu_shutdown			= iommu_shutdown_noop,
-- 
2.55.0.679.g6767b8d81c-goog