From: Mario Limonciello <mario.limonciello@xxxxxxx>
arch_init_invariance_cppc() is called at the end of
acpi_cppc_processor_probe() in order to configure frequency invariance
based upon the values from _CPC.
This however doesn't work on AMD CPPC shared memory designs that have
AMD preferred cores enabled because _CPC needs to be analyzed from all
cores to judge if preferred cores are enabled.
This issue manifests to users as a warning since commit 21fb59ab4b97
("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
```
Could not retrieve highest performance (-19)
```
However the warning isn't the cause of this, it was actually
commit 279f838a61f9 ("x86/amd: Detect preferred cores in
amd_get_boost_ratio_numerator()") which exposed the issue.
To fix this problem, change arch_init_invariance_cppc() into a new weak
symbol that is called at the end of acpi_processor_driver_init().
Each architecture that supports it can declare the symbol to override
the weak one.
Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Ivan Shapovalov <intelfx@xxxxxxxxxxxx>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v3:
* Weak symbol instead of macro to help riscv build failure
* Update commit message
* Add comment
---
arch/arm64/include/asm/topology.h | 2 +-
arch/x86/include/asm/topology.h | 2 +-
drivers/acpi/cppc_acpi.c | 6 ------
drivers/acpi/processor_driver.c | 9 +++++++++
include/acpi/processor.h | 2 ++
5 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h
index 5fc3af9f8f29b..8a1860877967e 100644
--- a/arch/arm64/include/asm/topology.h
+++ b/arch/arm64/include/asm/topology.h
@@ -27,7 +27,7 @@ void update_freq_counters_refs(void);
#define arch_scale_freq_ref topology_get_freq_ref
#ifdef CONFIG_ACPI_CPPC_LIB
-#define arch_init_invariance_cppc topology_init_cpu_capacity_cppc
+#define acpi_processor_init_invariance_cppc topology_init_cpu_capacity_cppc
#endif
/* Replace task scheduler's default cpu-invariant accounting */
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index aef70336d6247..0fb705524aeaa 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -307,7 +307,7 @@ extern void arch_scale_freq_tick(void);
#ifdef CONFIG_ACPI_CPPC_LIB
void init_freq_invariance_cppc(void);
-#define arch_init_invariance_cppc init_freq_invariance_cppc
+#define acpi_processor_init_invariance_cppc init_freq_invariance_cppc
#endif
#endif /* _ASM_X86_TOPOLOGY_H */
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 1a40f0514eaa3..5c0cc7aae8726 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
* )
*/
-#ifndef arch_init_invariance_cppc
-static inline void arch_init_invariance_cppc(void) { }
-#endif
-
/**
* acpi_cppc_processor_probe - Search for per CPU _CPC objects.
* @pr: Ptr to acpi_processor containing this CPU's logical ID.
@@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
goto out_free;
}
- arch_init_invariance_cppc();
-
kfree(output.pointer);
return 0;
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index cb52dd000b958..3b281bc1e73c3 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -237,6 +237,9 @@ static struct notifier_block acpi_processor_notifier_block = {
.notifier_call = acpi_processor_notifier,
};
+void __weak acpi_processor_init_invariance_cppc(void)
+{ }
+
/*
* We keep the driver loaded even when ACPI is not running.
* This is needed for the powernow-k8 driver, that works even without
@@ -270,6 +273,12 @@ static int __init acpi_processor_driver_init(void)
NULL, acpi_soft_cpu_dead);
acpi_processor_throttling_init();
+
+ /*
+ * Frequency invariance calculations on AMD platforms can't be run until
+ * after acpi_cppc_processor_probe() has been called for all online CPUs.
+ */
+ acpi_processor_init_invariance_cppc();
return 0;
err:
driver_unregister(&acpi_processor_driver);
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index e6f6074eadbf3..a17e97e634a68 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -465,4 +465,6 @@ extern int acpi_processor_ffh_lpi_probe(unsigned int cpu);
extern int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi);
#endif
+void acpi_processor_init_invariance_cppc(void);
+
#endif
base-commit: 6db936d4ac0fe281af48b4d1ebf69b1523bbac31
--
2.43.0
