]> www.infradead.org Git - users/hch/configfs.git/commit
ACPI: processor: Move arch_init_invariance_cppc() call later
authorMario Limonciello <mario.limonciello@amd.com>
Mon, 4 Nov 2024 22:28:55 +0000 (16:28 -0600)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 6 Nov 2024 20:31:36 +0000 (21:31 +0100)
commitb79276dcac9124a79c8cf7cc8fbdd3d4c3c9a7c7
tree0ae35fd8669dea40d3718625f2c9421e1fdeca22
parent59b723cd2adbac2a34fc8e12c74ae26ae45bf230
ACPI: processor: Move arch_init_invariance_cppc() call later

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.

Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the
architectures using the generic arch_topology.c code.

Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Ivan Shapovalov <intelfx@intelfx.name>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20241104222855.3959267-1-superm1@kernel.org
[ rjw: Changelog edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arch/arm64/include/asm/topology.h
arch/x86/include/asm/topology.h
arch/x86/kernel/acpi/cppc.c
drivers/acpi/cppc_acpi.c
drivers/acpi/processor_driver.c
drivers/base/arch_topology.c
include/acpi/processor.h
include/linux/arch_topology.h