drm/msm/mdp4: refactor HW revision detection into read_mdp_hw_revision

Inspired by MDP5 code.
Also use DRM_DEV_INFO for MDP version as MDP5 does.

Cosmetic change: uint32_t -> u32 - checkpatch suggestion.
Signed-off-by: David Heidelberg <david@ixit.cz>
Link: https://lore.kernel.org/r/20210705231641.315804-1-david@ixit.czReviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c

@@ -19,20 +19,13 @@ static int mdp4_hw_init(struct msm_kms *kms)
 {
 	struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
 	struct drm_device *dev = mdp4_kms->dev;
-	uint32_t version, major, minor, dmap_cfg, vg_cfg;
+	u32 major, minor, dmap_cfg, vg_cfg;
 	unsigned long clk;
 	int ret = 0;
 
 	pm_runtime_get_sync(dev->dev);
 
-	mdp4_enable(mdp4_kms);
-	version = mdp4_read(mdp4_kms, REG_MDP4_VERSION);
-	mdp4_disable(mdp4_kms);
-
-	major = FIELD(version, MDP4_VERSION_MAJOR);
-	minor = FIELD(version, MDP4_VERSION_MINOR);
-
-	DBG("found MDP4 version v%d.%d", major, minor);
+	read_mdp_hw_revision(mdp4_kms, &major, &minor);
 
 	if (major != 4) {
 		DRM_DEV_ERROR(dev->dev, "unexpected MDP version: v%d.%d\n",
@@ -411,6 +404,22 @@ static int modeset_init(struct mdp4_kms *mdp4_kms)
 	return ret;
 }
 
+static void read_mdp_hw_revision(struct mdp4_kms *mdp4_kms,
+				 u32 *major, u32 *minor)
+{
+	struct drm_device *dev = mdp4_kms->dev;
+	u32 version;
+
+	mdp4_enable(mdp4_kms);
+	version = mdp4_read(mdp4_kms, REG_MDP4_VERSION);
+	mdp4_disable(mdp4_kms);
+
+	*major = FIELD(version, MDP4_VERSION_MAJOR);
+	*minor = FIELD(version, MDP4_VERSION_MINOR);
+
+	DRM_DEV_INFO(dev->dev, "MDP4 version v%d.%d", *major, *minor);
+}
+
 struct msm_kms *mdp4_kms_init(struct drm_device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev->dev);