drm/amd/powerplay: support enabled ppfeatures retrieving and setting V3

User can use "ppfeatures" sysfs interface to retrieve and set enabled
powerplay features.

V2: expose this feature for Vega10 and later dGPUs
V3: squash in removal of unused variable (Alex)

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 71 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
index 51eb2cf42b81..f21f294e6735 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
@@ -626,6 +626,60 @@ static ssize_t amdgpu_get_pp_od_clk_voltage(struct device *dev,
 }
 
 /**
+ * DOC: ppfeatures
+ *
+ * The amdgpu driver provides a sysfs API for adjusting what powerplay
+ * features to be enabled. The file ppfeatures is used for this. And
+ * this is only available for Vega10 and later dGPUs.
+ *
+ * Reading back the file will show you the followings:
+ * - Current ppfeature masks
+ * - List of the all supported powerplay features with their naming,
+ *   bitmasks and enablement status('Y'/'N' means "enabled"/"disabled").
+ *
+ * To manually enable or disable a specific feature, just set or clear
+ * the corresponding bit from original ppfeature masks and input the
+ * new ppfeature masks.
+ */
+static ssize_t amdgpu_set_ppfeature_status(struct device *dev,
+                struct device_attribute *attr,
+                const char *buf,
+                size_t count)
+{
+        struct drm_device *ddev = dev_get_drvdata(dev);
+        struct amdgpu_device *adev = ddev->dev_private;
+        uint64_t featuremask;
+        int ret;
+
+        ret = kstrtou64(buf, 0, &featuremask);
+        if (ret)
+                return -EINVAL;
+
+        pr_debug("featuremask = 0x%llx\n", featuremask);
+
+        if (adev->powerplay.pp_funcs->set_ppfeature_status) {
+                ret = amdgpu_dpm_set_ppfeature_status(adev, featuremask);
+                if (ret)
+                        return -EINVAL;
+        }
+
+        return count;
+}
+
+static ssize_t amdgpu_get_ppfeature_status(struct device *dev,
+                struct device_attribute *attr,
+                char *buf)
+{
+        struct drm_device *ddev = dev_get_drvdata(dev);
+        struct amdgpu_device *adev = ddev->dev_private;
+
+        if (adev->powerplay.pp_funcs->get_ppfeature_status)
+                return amdgpu_dpm_get_ppfeature_status(adev, buf);
+
+        return snprintf(buf, PAGE_SIZE, "\n");
+}
+
+/**
  * DOC: pp_dpm_sclk pp_dpm_mclk pp_dpm_pcie
  *
  * The amdgpu driver provides a sysfs API for adjusting what power levels
@@ -1051,6 +1105,9 @@ static DEVICE_ATTR(pp_od_clk_voltage, S_IRUGO | S_IWUSR,
 static DEVICE_ATTR(gpu_busy_percent, S_IRUGO,
                 amdgpu_get_busy_percent, NULL);
 static DEVICE_ATTR(pcie_bw, S_IRUGO, amdgpu_get_pcie_bw, NULL);
+static DEVICE_ATTR(ppfeatures, S_IRUGO | S_IWUSR,
+                amdgpu_get_ppfeature_status,
+                amdgpu_set_ppfeature_status);
 
 static ssize_t amdgpu_hwmon_show_temp(struct device *dev,
                                       struct device_attribute *attr,
@@ -2241,6 +2298,17 @@ int amdgpu_pm_sysfs_init(struct amdgpu_device *adev)
                 return ret;
         }
 
+        if ((adev->asic_type >= CHIP_VEGA10) &&
+            !(adev->flags & AMD_IS_APU)) {
+                ret = device_create_file(adev->dev,
+                                &dev_attr_ppfeatures);
+                if (ret) {
+                        DRM_ERROR("failed to create device file "
+                                        "ppfeatures\n");
+                        return ret;
+                }
+        }
+
         adev->pm.sysfs_initialized = true;
 
         return 0;
@@ -2276,6 +2344,9 @@ void amdgpu_pm_sysfs_fini(struct amdgpu_device *adev)
         device_remove_file(adev->dev, &dev_attr_gpu_busy_percent);
         if (adev->flags & !AMD_IS_APU)
                 device_remove_file(adev->dev, &dev_attr_pcie_bw);
+        if ((adev->asic_type >= CHIP_VEGA10) &&
+            !(adev->flags & AMD_IS_APU))
+                device_remove_file(adev->dev, &dev_attr_ppfeatures);
 }
 
 void amdgpu_pm_compute_clocks(struct amdgpu_device *adev)