[PATCH 09/16] drm/i915/guc/slpc: Add get max/min freq hooks

[Vinay Belgaumkar <vinay.belgaumkar@xxxxxxxxx>]

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.

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 | 58 +++++++++++++++++++++
 drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h |  2 +
 2 files changed, 60 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 19cb26479942..98a283d31734 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
@@ -278,6 +278,35 @@ int intel_guc_slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 val)
 	return ret;
 }
 
+int intel_guc_slpc_get_max_freq(struct intel_guc_slpc *slpc, u32 *val)
+{
+	struct slpc_shared_data *data;
+	intel_wakeref_t wakeref;
+	struct drm_i915_private *i915 = guc_to_gt(slpc_to_guc(slpc))->i915;
+	int ret = 0;
+
+	wakeref = intel_runtime_pm_get(&i915->runtime_pm);
+
+	/* Force GuC to update task data */
+	if (slpc_read_task_state(slpc)) {
+		DRM_ERROR("Unable to update task data");
+		ret = -EIO;
+		goto done;
+	}
+
+	GEM_BUG_ON(!slpc->vma);
+
+	drm_clflush_virt_range(slpc->vaddr, sizeof(struct slpc_shared_data));
+	data = slpc->vaddr;
+
+	*val = DIV_ROUND_CLOSEST(data->task_state_data.max_unslice_freq *
+				GT_FREQUENCY_MULTIPLIER, GEN9_FREQ_SCALER);
+
+done:
+	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
+	return ret;
+}
+
 /**
  * intel_guc_slpc_min_freq_set() - Set min frequency limit for SLPC.
  * @slpc: pointer to intel_guc_slpc.
@@ -312,6 +341,35 @@ int intel_guc_slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 val)
 	return ret;
 }
 
+int intel_guc_slpc_get_min_freq(struct intel_guc_slpc *slpc, u32 *val)
+{
+	struct slpc_shared_data *data;
+	intel_wakeref_t wakeref;
+	struct drm_i915_private *i915 = guc_to_gt(slpc_to_guc(slpc))->i915;
+	int ret = 0;
+
+	wakeref = intel_runtime_pm_get(&i915->runtime_pm);
+
+	/* Force GuC to update task data */
+	if (slpc_read_task_state(slpc)) {
+		DRM_ERROR("Unable to update task data");
+		ret = -EIO;
+		goto done;
+	}
+
+	GEM_BUG_ON(!slpc->vma);
+
+	drm_clflush_virt_range(slpc->vaddr, sizeof(struct slpc_shared_data));
+	data = slpc->vaddr;
+
+	*val = DIV_ROUND_CLOSEST(data->task_state_data.min_unslice_freq *
+				GT_FREQUENCY_MULTIPLIER, GEN9_FREQ_SCALER);
+
+done:
+	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
+	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 a473e1ea7c10..2cb830cdacb5 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.h
@@ -36,5 +36,7 @@ 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