drm/radeon/kms: add info query for max pipes

The maximum number of pipes is needed by the user space compute
driver to calculate the number of wavefronts per thread group.
Signed-off-by: Tom Stellard <thomas.stellard@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_drv.c

@@ -56,9 +56,10 @@
  *   2.12.0 - RADEON_CS_KEEP_TILING_FLAGS
  *   2.13.0 - virtual memory support, streamout
  *   2.14.0 - add evergreen tiling informations
+ *   2.15.0 - add max_pipes query
  */
 #define KMS_DRIVER_MAJOR	2
-#define KMS_DRIVER_MINOR	14
+#define KMS_DRIVER_MINOR	15
 #define KMS_DRIVER_PATCHLEVEL	0
 int radeon_driver_load_kms(struct drm_device *dev, unsigned long flags);
 int radeon_driver_unload_kms(struct drm_device *dev);

drivers/gpu/drm/radeon/radeon_kms.c

@@ -264,6 +264,19 @@ int radeon_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 			return -EINVAL;
 		value = RADEON_IB_VM_MAX_SIZE;
 		break;
+	case RADEON_INFO_MAX_PIPES:
+		if (rdev->family >= CHIP_CAYMAN)
+			value = rdev->config.cayman.max_pipes_per_simd;
+		else if (rdev->family >= CHIP_CEDAR)
+			value = rdev->config.evergreen.max_pipes;
+		else if (rdev->family >= CHIP_RV770)
+			value = rdev->config.rv770.max_pipes;
+		else if (rdev->family >= CHIP_R600)
+			value = rdev->config.r600.max_pipes;
+		else {
+			return -EINVAL;
+		}
+		break;
 	default:
 		DRM_DEBUG_KMS("Invalid request %d\n", info->request);
 		return -EINVAL;

include/drm/radeon_drm.h

@@ -962,6 +962,8 @@ struct drm_radeon_cs {
 #define RADEON_INFO_VA_START		0x0e
 /* maximum size of ib using the virtual memory cs */
 #define RADEON_INFO_IB_VM_MAX_SIZE	0x0f
+/* max pipes - needed for compute shaders */
+#define RADEON_INFO_MAX_PIPES		0x10
 
 struct drm_radeon_info {
 	uint32_t		request;