cpufreq/amd-pstate: Toggle auto_sel in active mode on shared memory systems

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On shared memory systems, the EPP configuration path (handled via
cppc_set_epp_perf()) is responsible for toggling on the CPPC autonomous
selection register (auto_sel).

Currently, shmem_init_perf() returns early without doing any of the auto_sel
configuration steps if cppc_state is AMD_PSTATE_ACTIVE. This skips enabling
auto_sel, leaving the CPU in non-autonomous mode.

Remove the early return check in shmem_init_perf() when cppc_state is
AMD_PSTATE_ACTIVE. Toggling auto_sel is necessary for the active mode on
shared memory systems to function based on the ACPI spec for CPPC v2 and
below.

Fixes: 2dd6d0ebf7 ("cpufreq: amd-pstate: Add guided autonomous mode")
Assisted-by: Antigravity:gemini-3.5-flash
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Marco Scardovi <scardracs@disroot.org>
Reviewed-by: K Prateek Nayak <kprateek.anayk@amd.com>
Link: https://lore.kernel.org/r/20260609073042.81275-3-scardracs@disroot.org
Signed-off-by: Mario Limonciello <superm1@kernel.org>

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This commit is contained in:

Marco Scardovi 2026-06-09 09:29:04 +02:00 • committed by Mario Limonciello

parent 57476909c3

commit 9dfd13f80c

1 changed files with 0 additions and 3 deletions

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drivers/cpufreq/amd-pstate.c

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