drm/msm: Add a property for the GMEM base

Return the base address of GMEM in virtual address space as
a parameter.

Change-Id: Ic0dedbad3b849052313e4673efcf6c22bc81f21f
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>

drivers/gpu/drm/msm/adreno/adreno_gpu.c

@@ -35,6 +35,9 @@ int adreno_get_param(struct msm_gpu *gpu, uint32_t param, uint64_t *value)
 	case MSM_PARAM_GMEM_SIZE:
 		*value = adreno_gpu->gmem;
 		return 0;
+	case MSM_PARAM_GMEM_BASE:
+		*value = 0x100000;
+		return 0;
 	case MSM_PARAM_CHIP_ID:
 		*value = adreno_gpu->rev.patchid |
 				(adreno_gpu->rev.minor << 8) |

include/uapi/drm/msm_drm.h

@@ -54,6 +54,7 @@ struct drm_msm_timespec {
 #define MSM_PARAM_CHIP_ID    0x03
 #define MSM_PARAM_MAX_FREQ   0x04
 #define MSM_PARAM_TIMESTAMP  0x05
+#define MSM_PARAM_GMEM_BASE  0x06
 
 struct drm_msm_param {
 	__u32 pipe;           /* in, MSM_PIPE_x */