drm/i915: expose _SLICE_MASK GETPARM

Enables userspace to determine the number of slices enabled and also
know what specific slices are enabled. This information is required, for
example, to be able to analyse some OA counter reports where the counter
configuration depends on the HW slice configuration.

Signed-off-by: Robert Bragg <[email protected]>

Author: rib

drivers/gpu/drm/i915/i915_dma.c

@@ -170,6 +170,11 @@ static int i915_getparam(struct drm_device *dev, void *data,
 	case I915_PARAM_HAS_RESOURCE_STREAMER:
 		value = HAS_RESOURCE_STREAMER(dev);
 		break;
+	case I915_PARAM_SLICE_MASK:
+		value = INTEL_INFO(dev_priv)->slice_mask;
+		if (!value)
+			return -ENODEV;
+		break;
 	default:
 		DRM_DEBUG("Unknown parameter %d\n", param->param);
 		return -EINVAL;

include/uapi/drm/i915_drm.h

@@ -358,6 +358,7 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_EU_TOTAL		 34
 #define I915_PARAM_HAS_GPU_RESET	 35
 #define I915_PARAM_HAS_RESOURCE_STREAMER 36
+#define I915_PARAM_SLICE_MASK		 45 /* XXX: rebase before landing */
 
 typedef struct drm_i915_getparam {
 	__s32 param;