drm/radeon: add query to fetch the max engine clock (v2)

This is needed for reporting the max GPU engine clock
in OpenCL.  This just reports the max possible engine
clock, it does not take into account current conditions
that may limit that clock.

v2: fix query number for merge with 3.13
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_kms.c

@@ -470,6 +470,13 @@ static int radeon_info_ioctl(struct drm_device *dev, void *data, struct drm_file
 			DRM_DEBUG_KMS("BACKEND_ENABLED_MASK is si+ only!\n");
 		}
 		break;
+	case RADEON_INFO_MAX_SCLK:
+		if ((rdev->pm.pm_method == PM_METHOD_DPM) &&
+		    rdev->pm.dpm_enabled)
+			*value = rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.sclk * 10;
+		else
+			*value = rdev->pm.default_sclk * 10;
+		break;
 	default:
 		DRM_DEBUG_KMS("Invalid request %d\n", info->request);
 		return -EINVAL;

drivers/gpu/drm/radeon/rv770_dpm.c

@@ -2251,7 +2251,6 @@ static void rv7xx_parse_pplib_clock_info(struct radeon_device *rdev,
 		pl->vddci = vddci;
 	}
 
-	if (rdev->family >= CHIP_BARTS) {
 	if ((rps->class & ATOM_PPLIB_CLASSIFICATION_UI_MASK) ==
 	    ATOM_PPLIB_CLASSIFICATION_UI_PERFORMANCE) {
 		rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.sclk = pl->sclk;
@@ -2259,7 +2258,6 @@ static void rv7xx_parse_pplib_clock_info(struct radeon_device *rdev,
 		rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.vddc = pl->vddc;
 		rdev->pm.dpm.dyn_state.max_clock_voltage_on_ac.vddci = pl->vddci;
 	}
-	}
 }
 
 int rv7xx_parse_power_table(struct radeon_device *rdev)

include/uapi/drm/radeon_drm.h

@@ -985,6 +985,8 @@ struct drm_radeon_cs {
 #define RADEON_INFO_CIK_MACROTILE_MODE_ARRAY	0x18
 /* query the number of render backends */
 #define RADEON_INFO_SI_BACKEND_ENABLED_MASK	0x19
+/* max engine clock - needed for OpenCL */
+#define RADEON_INFO_MAX_SCLK		0x1a
 
 
 struct drm_radeon_info {