drm/msm: Add support for pointer params

The 64b value field is already suffient to hold a pointer instead of
immediate, but we also need a length field.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20220317165144.222101-2-robdclark@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>

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

@@ -229,10 +229,14 @@ adreno_iommu_create_address_space(struct msm_gpu *gpu,
 }
 
 int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
-		     uint32_t param, uint64_t *value)
+		     uint32_t param, uint64_t *value, uint32_t *len)
 {
 	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
 
+	/* No pointer params yet */
+	if (*len != 0)
+		return -EINVAL;
+
 	switch (param) {
 	case MSM_PARAM_GPU_ID:
 		*value = adreno_gpu->info->revn;
@@ -284,8 +288,12 @@ int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
 }
 
 int adreno_set_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
-		     uint32_t param, uint64_t value)
+		     uint32_t param, uint64_t value, uint32_t len)
 {
+	/* No pointer params yet */
+	if (len != 0)
+		return -EINVAL;
+
 	switch (param) {
 	case MSM_PARAM_SYSPROF:
 		if (!capable(CAP_SYS_ADMIN))

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

@@ -281,9 +281,9 @@ static inline int adreno_is_a650_family(struct adreno_gpu *gpu)
 }
 
 int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
-		     uint32_t param, uint64_t *value);
+		     uint32_t param, uint64_t *value, uint32_t *len);
 int adreno_set_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
-		     uint32_t param, uint64_t value);
+		     uint32_t param, uint64_t value, uint32_t len);
 const struct firmware *adreno_request_fw(struct adreno_gpu *adreno_gpu,
 		const char *fwname);
 struct drm_gem_object *adreno_fw_create_bo(struct msm_gpu *gpu,

drivers/gpu/drm/msm/msm_drv.c

@@ -613,7 +613,7 @@ static int msm_ioctl_get_param(struct drm_device *dev, void *data,
 	/* for now, we just have 3d pipe.. eventually this would need to
 	 * be more clever to dispatch to appropriate gpu module:
 	 */
-	if (args->pipe != MSM_PIPE_3D0)
+	if ((args->pipe != MSM_PIPE_3D0) || (args->pad != 0))
 		return -EINVAL;
 
 	gpu = priv->gpu;
@@ -622,7 +622,7 @@ static int msm_ioctl_get_param(struct drm_device *dev, void *data,
 		return -ENXIO;
 
 	return gpu->funcs->get_param(gpu, file->driver_priv,
-				     args->param, &args->value);
+				     args->param, &args->value, &args->len);
 }
 
 static int msm_ioctl_set_param(struct drm_device *dev, void *data,
@@ -632,7 +632,7 @@ static int msm_ioctl_set_param(struct drm_device *dev, void *data,
 	struct drm_msm_param *args = data;
 	struct msm_gpu *gpu;
 
-	if (args->pipe != MSM_PIPE_3D0)
+	if ((args->pipe != MSM_PIPE_3D0) || (args->pad != 0))
 		return -EINVAL;
 
 	gpu = priv->gpu;
@@ -641,7 +641,7 @@ static int msm_ioctl_set_param(struct drm_device *dev, void *data,
 		return -ENXIO;
 
 	return gpu->funcs->set_param(gpu, file->driver_priv,
-				     args->param, args->value);
+				     args->param, args->value, args->len);
 }
 
 static int msm_ioctl_gem_new(struct drm_device *dev, void *data,

drivers/gpu/drm/msm/msm_gpu.h

@@ -44,9 +44,9 @@ struct msm_gpu_config {
  */
 struct msm_gpu_funcs {
 	int (*get_param)(struct msm_gpu *gpu, struct msm_file_private *ctx,
-			 uint32_t param, uint64_t *value);
+			 uint32_t param, uint64_t *value, uint32_t *len);
 	int (*set_param)(struct msm_gpu *gpu, struct msm_file_private *ctx,
-			 uint32_t param, uint64_t value);
+			 uint32_t param, uint64_t value, uint32_t len);
 	int (*hw_init)(struct msm_gpu *gpu);
 	int (*pm_suspend)(struct msm_gpu *gpu);
 	int (*pm_resume)(struct msm_gpu *gpu);

drivers/gpu/drm/msm/msm_rd.c

@@ -180,6 +180,7 @@ static int rd_open(struct inode *inode, struct file *file)
 	struct msm_gpu *gpu = priv->gpu;
 	uint64_t val;
 	uint32_t gpu_id;
+	uint32_t zero = 0;
 	int ret = 0;
 
 	if (!gpu)
@@ -200,12 +201,12 @@ static int rd_open(struct inode *inode, struct file *file)
 	 *
 	 * Note: These particular params do not require a context
 	 */
-	gpu->funcs->get_param(gpu, NULL, MSM_PARAM_GPU_ID, &val);
+	gpu->funcs->get_param(gpu, NULL, MSM_PARAM_GPU_ID, &val, &zero);
 	gpu_id = val;
 
 	rd_write_section(rd, RD_GPU_ID, &gpu_id, sizeof(gpu_id));
 
-	gpu->funcs->get_param(gpu, NULL, MSM_PARAM_CHIP_ID, &val);
+	gpu->funcs->get_param(gpu, NULL, MSM_PARAM_CHIP_ID, &val, &zero);
 	rd_write_section(rd, RD_CHIP_ID, &val, sizeof(val));
 
 out:

include/uapi/drm/msm_drm.h

@@ -95,6 +95,8 @@ struct drm_msm_param {
 	__u32 pipe;           /* in, MSM_PIPE_x */
 	__u32 param;          /* in, MSM_PARAM_x */
 	__u64 value;          /* out (get_param) or in (set_param) */
+	__u32 len;            /* zero for non-pointer params */
+	__u32 pad;            /* must be zero */
 };
 
 /*