Merge tag 'pm-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "The most signigicant change here is the addition of a new cpufreq
  'P-state' driver for AMD processors as a better replacement for the
  venerable acpi-cpufreq driver.

  There are also other cpufreq updates (in the core, intel_pstate, ARM
  drivers), PM core updates (mostly related to adding new macros for
  declaring PM operations which should make the lives of driver
  developers somewhat easier), and a bunch of assorted fixes and
  cleanups.

  Summary:

   - Add new P-state driver for AMD processors (Huang Rui).

   - Fix initialization of min and max frequency QoS requests in the
     cpufreq core (Rafael Wysocki).

   - Fix EPP handling on Alder Lake in intel_pstate (Srinivas
     Pandruvada).

   - Make intel_pstate update cpuinfo.max_freq when notified of HWP
     capabilities changes and drop a redundant function call from that
     driver (Rafael Wysocki).

   - Improve IRQ support in the Qcom cpufreq driver (Ard Biesheuvel,
     Stephen Boyd, Vladimir Zapolskiy).

   - Fix double devm_remap() in the Mediatek cpufreq driver (Hector
     Yuan).

   - Introduce thermal pressure helpers for cpufreq CPU cooling (Lukasz
     Luba).

   - Make cpufreq use default_groups in kobj_type (Greg Kroah-Hartman).

   - Make cpuidle use default_groups in kobj_type (Greg Kroah-Hartman).

   - Fix two comments in cpuidle code (Jason Wang, Yang Li).

   - Allow model-specific normal EPB value to be used in the intel_epb
     sysfs attribute handling code (Srinivas Pandruvada).

   - Simplify locking in pm_runtime_put_suppliers() (Rafael Wysocki).

   - Add safety net to supplier device release in the runtime PM core
     code (Rafael Wysocki).

   - Capture device status before disabling runtime PM for it (Rafael
     Wysocki).

   - Add new macros for declaring PM operations to allow drivers to
     avoid guarding them with CONFIG_PM #ifdefs or __maybe_unused and
     update some drivers to use these macros (Paul Cercueil).

   - Allow ACPI hardware signature to be honoured during restore from
     hibernation (David Woodhouse).

   - Update outdated operating performance points (OPP) documentation
     (Tang Yizhou).

   - Reduce log severity for informative message regarding frequency
     transition failures in devfreq (Tzung-Bi Shih).

   - Add DRAM frequency controller devfreq driver for Allwinner sunXi
     SoCs (Samuel Holland).

   - Add missing COMMON_CLK dependency to sun8i devfreq driver (Arnd
     Bergmann).

   - Add support for new layout of Psys PowerLimit Register on SPR to
     the Intel RAPL power capping driver (Zhang Rui).

   - Fix typo in a comment in idle_inject.c (Jason Wang).

   - Remove unused function definition from the DTPM (Dynamit Thermal
     Power Management) power capping framework (Daniel Lezcano).

   - Reduce DTPM trace verbosity (Daniel Lezcano)"

* tag 'pm-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits)
  x86, sched: Fix undefined reference to init_freq_invariance_cppc() build error
  cpufreq: amd-pstate: Fix Kconfig dependencies for AMD P-State
  cpufreq: amd-pstate: Fix struct amd_cpudata kernel-doc comment
  cpuidle: use default_groups in kobj_type
  x86: intel_epb: Allow model specific normal EPB value
  MAINTAINERS: Add AMD P-State driver maintainer entry
  Documentation: amd-pstate: Add AMD P-State driver introduction
  cpufreq: amd-pstate: Add AMD P-State performance attributes
  cpufreq: amd-pstate: Add AMD P-State frequencies attributes
  cpufreq: amd-pstate: Add boost mode support for AMD P-State
  cpufreq: amd-pstate: Add trace for AMD P-State module
  cpufreq: amd-pstate: Introduce the support for the processors with shared memory solution
  cpufreq: amd-pstate: Add fast switch function for AMD P-State
  cpufreq: amd-pstate: Introduce a new AMD P-State driver to support future processors
  ACPI: CPPC: Add CPPC enable register function
  ACPI: CPPC: Check present CPUs for determining _CPC is valid
  ACPI: CPPC: Implement support for SystemIO registers
  x86/msr: Add AMD CPPC MSR definitions
  x86/cpufeatures: Add AMD Collaborative Processor Performance Control feature flag
  cpufreq: use default_groups in kobj_type
  ...

1 files changed, 21 insertions, 5 deletions

diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index 4b8454f26ca1..a60ff5dfed3a 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -874,11 +874,11 @@ static inline void acpi_sleep_syscore_init(void) {}
 #ifdef CONFIG_HIBERNATION
 static unsigned long s4_hardware_signature;
 static struct acpi_table_facs *facs;
-static bool nosigcheck;
+static int sigcheck = -1; /* Default behaviour is just to warn */
 
-void __init acpi_no_s4_hw_signature(void)
+void __init acpi_check_s4_hw_signature(int check)
 {
-	nosigcheck = true;
+	sigcheck = check;
 }
 
 static int acpi_hibernation_begin(pm_message_t stage)
@@ -1004,12 +1004,28 @@ static void acpi_sleep_hibernate_setup(void)
 	hibernation_set_ops(old_suspend_ordering ?
 			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
 	sleep_states[ACPI_STATE_S4] = 1;
-	if (nosigcheck)
+	if (!sigcheck)
 		return;
 
 	acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
-	if (facs)
+	if (facs) {
+		/*
+		 * s4_hardware_signature is the local variable which is just
+		 * used to warn about mismatch after we're attempting to
+		 * resume (in violation of the ACPI specification.)
+		 */
 		s4_hardware_signature = facs->hardware_signature;
+
+		if (sigcheck > 0) {
+			/*
+			 * If we're actually obeying the ACPI specification
+			 * then the signature is written out as part of the
+			 * swsusp header, in order to allow the boot kernel
+			 * to gracefully decline to resume.
+			 */
+			swsusp_hardware_signature = facs->hardware_signature;
+		}
+	}
 }
 #else /* !CONFIG_HIBERNATION */
 static inline void acpi_sleep_hibernate_setup(void) {}