drm/i915/gvt: add/modify interfaces for flag F_CMD_ACCESS

flag F_CMD_ACCESS represents whether an MMIO is able to be accessed by
GPU commands.
In this patch,
1. add interface to set this flag
2. rename intel_gvt_mmio_is_cmd_access() to
intel_gvt_mmio_is_cmd_accessible() and update its description message.
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200811070233.3387-1-yan.y.zhao@intel.com

drivers/gpu/drm/i915/gvt/cmd_parser.c

@@ -936,7 +936,7 @@ static int cmd_reg_handler(struct parser_exec_state *s,
 		return -EFAULT;
 	}
 
-	if (!intel_gvt_mmio_is_cmd_access(gvt, offset)) {
+	if (!intel_gvt_mmio_is_cmd_accessible(gvt, offset)) {
 		gvt_vgpu_err("%s access to non-render register (%x)\n",
 				cmd, offset);
 		return -EBADRQC;

drivers/gpu/drm/i915/gvt/gvt.h

@@ -594,17 +594,32 @@ static inline void intel_gvt_mmio_set_accessed(
 }
 
 /**
- * intel_gvt_mmio_is_cmd_accessed - mark a MMIO could be accessed by command
+ * intel_gvt_mmio_is_cmd_accessible - if a MMIO could be accessed by command
  * @gvt: a GVT device
  * @offset: register offset
  *
+ * Returns:
+ * True if an MMIO is able to be accessed by GPU commands
  */
-static inline bool intel_gvt_mmio_is_cmd_access(
+static inline bool intel_gvt_mmio_is_cmd_accessible(
 			struct intel_gvt *gvt, unsigned int offset)
 {
 	return gvt->mmio.mmio_attribute[offset >> 2] & F_CMD_ACCESS;
 }
 
+/**
+ * intel_gvt_mmio_set_cmd_accessible -
+ *				mark a MMIO could be accessible by command
+ * @gvt: a GVT device
+ * @offset: register offset
+ *
+ */
+static inline void intel_gvt_mmio_set_cmd_accessible(
+			struct intel_gvt *gvt, unsigned int offset)
+{
+	gvt->mmio.mmio_attribute[offset >> 2] |= F_CMD_ACCESS;
+}
+
 /**
  * intel_gvt_mmio_is_unalign - mark a MMIO could be accessed unaligned
  * @gvt: a GVT device