[PATCH v3 5/6] cpufreq: amd-pstate: Add a module device table

From: Mario Limonciello
Date: Thu Apr 14 2022 - 13:04:41 EST


`amd-pstate` currently only loads automatically if compiled into the
kernel. To improve the usability, add a module device table that
will load when AMD CPUs that support CPPC are detected.

Reviewed-by: Huang Rui <ray.huang@xxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v2->v3:
* Add Ray's tag
v1->v2:
* Add comment to indicate need of SBIOS support.

drivers/cpufreq/amd-pstate.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 8ae65a2072d6..3330504b7070 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -710,6 +710,17 @@ static void __exit amd_pstate_exit(void)
amd_pstate_enable(false);
}

+/*
+ * This will only match the HW feature, there still needs to be appropriate
+ * SBIOS support, so it's possible that in such cases this causes a module
+ * load with -ENODEV as the result.
+ */
+static const struct x86_cpu_id __maybe_unused amd_pstate_ids[] = {
+ X86_MATCH_VENDOR_FEATURE(AMD, X86_FEATURE_CPPC, NULL),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, amd_pstate_ids);
+
module_init(amd_pstate_init);
module_exit(amd_pstate_exit);

--
2.34.1