Add helpers to read the min/max frequency being used
by SLPC. This is done by send a H2G command which forces
SLPC to update the shared data struct which can then be
read. These helpers will be used in a sysfs patch later
on.
v2: Address review comments (Michal W)
v3: Return err in case of query failure (Michal W)
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@xxxxxxxxx>
Signed-off-by: Sundaresan Sujaritha <sujaritha.sundaresan@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c | 54 +++++++++++++++++++++
drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h | 2 +
2 files changed, 56 insertions(+)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
index 0959cc9e104a..816c9ee301bf 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
@@ -320,6 +320,33 @@ int intel_guc_slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 val)
return ret;
}
+/**
+ * intel_guc_slpc_get_max_freq() - Get max frequency limit for SLPC.
+ * @slpc: pointer to intel_guc_slpc.
+ * @val: pointer to val which will hold max frequency (MHz)
+ *
+ * This function will invoke GuC SLPC action to read the max frequency
+ * limit for unslice.
+ *
+ * Return: 0 on success, non-zero error code on failure.
+ */
+int intel_guc_slpc_get_max_freq(struct intel_guc_slpc *slpc, u32 *val)
+{
+ struct drm_i915_private *i915 = slpc_to_i915(slpc);
+ intel_wakeref_t wakeref;
+ int ret = 0;
+
+ with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
+ /* Force GuC to update task data */
+ ret = slpc_query_task_state(slpc);
+
+ if (!ret)
+ *val = slpc_decode_max_freq(slpc);
+ }
+
+ return ret;
+}
+
/**
* intel_guc_slpc_set_min_freq() - Set min frequency limit for SLPC.
* @slpc: pointer to intel_guc_slpc.
@@ -349,6 +376,33 @@ int intel_guc_slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 val)
return ret;
}
+/**
+ * intel_guc_slpc_get_min_freq() - Get min frequency limit for SLPC.
+ * @slpc: pointer to intel_guc_slpc.
+ * @val: pointer to val which will hold min frequency (MHz)
+ *
+ * This function will invoke GuC SLPC action to read the min frequency
+ * limit for unslice.
+ *
+ * Return: 0 on success, non-zero error code on failure.
+ */
+int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val)
+{
+ struct drm_i915_private *i915 = slpc_to_i915(slpc);
+ intel_wakeref_t wakeref;
+ int ret = 0;
+
+ with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
+ /* Force GuC to update task data */
+ ret = slpc_query_task_state(slpc);
+
+ if (!ret)
+ *val = slpc_decode_min_freq(slpc);
+ }
+
+ return ret;
+}
+
/*
* intel_guc_slpc_enable() - Start SLPC
* @slpc: pointer to intel_guc_slpc.
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
index 788d87ff7b58..78a7893ce489 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
@@ -31,5 +31,7 @@ int intel_guc_slpc_enable(struct intel_guc_slpc *slpc);
void intel_guc_slpc_fini(struct intel_guc_slpc *slpc);
int intel_guc_slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 val);
int intel_guc_slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 val);
+int intel_guc_slpc_get_max_freq(struct intel_guc_slpc *slpc, u32 *val);
+int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val);
#endif
--
2.25.0
