drm/exynos: check NV12M format specific to Exynos properly

this patch adds buf_cnt variable in exynos_drm_fb structure and
that means a buffer count to drm framebuffer and also adds two
functions to get/set the buffer count from/to exynos_drm_fb structure.
if pixel format is not DRM_FORMAT_NV12MT then it gets a buffer count
to drm framebuffer refering to mode_cmd->handles and offsets.
but when booted, the buffer count will always be 1 because pixel
format of console framebuffer is RGB format.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

4 files changed, 73 insertions, 17 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fb.c b/drivers/gpu/drm/exynos/exynos_drm_fb.c
index 4ccfe4328fab..98f8b839673a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fb.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fb.c
@@ -41,10 +41,12 @@
  * exynos specific framebuffer structure.
  *
  * @fb: drm framebuffer obejct.
+ * @buf_cnt: a buffer count to drm framebuffer.
  * @exynos_gem_obj: array of exynos specific gem object containing a gem object.
  */
 struct exynos_drm_fb {
         struct drm_framebuffer          fb;
+        unsigned int                    buf_cnt;
         struct exynos_drm_gem_obj       *exynos_gem_obj[MAX_FB_BUFFER];
 };
 
@@ -101,6 +103,25 @@ static struct drm_framebuffer_funcs exynos_drm_fb_funcs = {
         .dirty          = exynos_drm_fb_dirty,
 };
 
+void exynos_drm_fb_set_buf_cnt(struct drm_framebuffer *fb,
+                                                unsigned int cnt)
+{
+        struct exynos_drm_fb *exynos_fb;
+
+        exynos_fb = to_exynos_fb(fb);
+
+        exynos_fb->buf_cnt = cnt;
+}
+
+unsigned int exynos_drm_fb_get_buf_cnt(struct drm_framebuffer *fb)
+{
+        struct exynos_drm_fb *exynos_fb;
+
+        exynos_fb = to_exynos_fb(fb);
+
+        return exynos_fb->buf_cnt;
+}
+
 struct drm_framebuffer *
 exynos_drm_framebuffer_init(struct drm_device *dev,
                             struct drm_mode_fb_cmd2 *mode_cmd,
@@ -127,6 +148,43 @@ exynos_drm_framebuffer_init(struct drm_device *dev,
         return &exynos_fb->fb;
 }
 
+static u32 exynos_drm_format_num_buffers(struct drm_mode_fb_cmd2 *mode_cmd)
+{
+        unsigned int cnt = 0;
+
+        if (mode_cmd->pixel_format != DRM_FORMAT_NV12)
+                return drm_format_num_planes(mode_cmd->pixel_format);
+
+        while (cnt != MAX_FB_BUFFER) {
+                if (!mode_cmd->handles[cnt])
+                        break;
+                cnt++;
+        }
+
+        /*
+         * check if NV12 or NV12M.
+         *
+         * NV12
+         * handles[0] = base1, offsets[0] = 0
+         * handles[1] = base1, offsets[1] = Y_size
+         *
+         * NV12M
+         * handles[0] = base1, offsets[0] = 0
+         * handles[1] = base2, offsets[1] = 0
+         */
+        if (cnt == 2) {
+                /*
+                 * in case of NV12 format, offsets[1] is not 0 and
+                 * handles[0] is same as handles[1].
+                 */
+                if (mode_cmd->offsets[1] &&
+                        mode_cmd->handles[0] == mode_cmd->handles[1])
+                        cnt = 1;
+        }
+
+        return cnt;
+}
+
 static struct drm_framebuffer *
 exynos_user_fb_create(struct drm_device *dev, struct drm_file *file_priv,
                       struct drm_mode_fb_cmd2 *mode_cmd)
@@ -134,7 +192,6 @@ exynos_user_fb_create(struct drm_device *dev, struct drm_file *file_priv,
         struct drm_gem_object *obj;
         struct drm_framebuffer *fb;
         struct exynos_drm_fb *exynos_fb;
-        int nr;
         int i;
 
         DRM_DEBUG_KMS("%s\n", __FILE__);
@@ -152,9 +209,11 @@ exynos_user_fb_create(struct drm_device *dev, struct drm_file *file_priv,
         }
 
         exynos_fb = to_exynos_fb(fb);
-        nr = exynos_drm_format_num_buffers(fb->pixel_format);
+        exynos_fb->buf_cnt = exynos_drm_format_num_buffers(mode_cmd);
+
+        DRM_DEBUG_KMS("buf_cnt = %d\n", exynos_fb->buf_cnt);
 
-        for (i = 1; i < nr; i++) {
+        for (i = 1; i < exynos_fb->buf_cnt; i++) {
                 obj = drm_gem_object_lookup(dev, file_priv,
                                 mode_cmd->handles[i]);
                 if (!obj) {
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fb.h b/drivers/gpu/drm/exynos/exynos_drm_fb.h
index 50823756cdea..96262e54f76d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fb.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_fb.h
@@ -28,19 +28,6 @@
 #ifndef _EXYNOS_DRM_FB_H_
 #define _EXYNOS_DRM_FB_H
 
-static inline int exynos_drm_format_num_buffers(uint32_t format)
-{
-        switch (format) {
-        case DRM_FORMAT_NV12:
-        case DRM_FORMAT_NV12MT:
-                return 2;
-        case DRM_FORMAT_YUV420:
-                return 3;
-        default:
-                return 1;
-        }
-}
-
 struct drm_framebuffer *
 exynos_drm_framebuffer_init(struct drm_device *dev,
                             struct drm_mode_fb_cmd2 *mode_cmd,
@@ -52,4 +39,11 @@ struct exynos_drm_gem_buf *exynos_drm_fb_buffer(struct drm_framebuffer *fb,
 
 void exynos_drm_mode_config_init(struct drm_device *dev);
 
+/* set a buffer count to drm framebuffer. */
+void exynos_drm_fb_set_buf_cnt(struct drm_framebuffer *fb,
+                                                unsigned int cnt);
+
+/* get a buffer count to drm framebuffer. */
+unsigned int exynos_drm_fb_get_buf_cnt(struct drm_framebuffer *fb);
+
 #endif
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index f4ac43356583..d7205f8b2301 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -79,6 +79,9 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
                 return -EFAULT;
         }
 
+        /* buffer count to framebuffer always is 1 at booting time. */
+        exynos_drm_fb_set_buf_cnt(fb, 1);
+
         offset = fbi->var.xoffset * (fb->bits_per_pixel >> 3);
         offset += fbi->var.yoffset * fb->pitches[0];
 
diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c
index e1f94b746bd7..8c3036dd512b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_plane.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c
@@ -47,7 +47,7 @@ int exynos_plane_mode_set(struct drm_plane *plane, struct drm_crtc *crtc,
 
         DRM_DEBUG_KMS("[%d] %s\n", __LINE__, __func__);
 
-        nr = exynos_drm_format_num_buffers(fb->pixel_format);
+        nr = exynos_drm_fb_get_buf_cnt(fb);
         for (i = 0; i < nr; i++) {
                 struct exynos_drm_gem_buf *buffer = exynos_drm_fb_buffer(fb, i);