drm_format_plane_width_bytes() calculates and returns the number of bytes
for given width of specified format. The calculation uses @cpp
in drm format info for byte-aligned formats. If the format isn't
byte-aligned, @cpp should 0, and the macro pixel information is used.
This avoids bit level rounding.
Use this drm_fb_cma_get_gem_addr() for offset calculation.
Signed-off-by: Hyun Kwon <hyun.kwon@xxxxxxxxxx>
---
v3
- Update according to member changes
- Use @cpp for byte-aligned formats, and macro-pixel for non byte-aligned ones
- Squash a change in drm_fb_cma_helper.c into this
v2
- This function is added
---
---
drivers/gpu/drm/drm_fb_cma_helper.c | 3 ++-
drivers/gpu/drm/drm_fourcc.c | 35 +++++++++++++++++++++++++++++++++++
include/drm/drm_fourcc.h | 2 ++
3 files changed, 39 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
index 186d00a..271175e 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -124,7 +124,8 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer *fb,
return 0;
paddr = obj->paddr + fb->offsets[plane];
- paddr += fb->format->cpp[plane] * (state->src_x >> 16);
+ paddr += drm_format_plane_width_bytes(fb->format, plane,
+ state->src_x >> 16);
paddr += fb->pitches[plane] * (state->src_y >> 16);
return paddr;
diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
index 9c0152d..ed95de2 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -348,3 +348,38 @@ int drm_format_plane_height(int height, uint32_t format, int plane)
return height / info->vsub;
}
EXPORT_SYMBOL(drm_format_plane_height);
+
+/**
+ * drm_format_plane_width_bytes - bytes of the given width of the plane
+ * @info: DRM format information
+ * @plane: plane index
+ * @width: width to get the number of bytes
+ *
+ * This returns the number of bytes for given @width and @plane.
+ * The @cpp or macro pixel information should be valid.
+ *
+ * Returns:
+ * The bytes of @width of @plane. 0 for invalid format info.
+ */
+int drm_format_plane_width_bytes(const struct drm_format_info *info,
+ int plane, int width)
+{
+ if (!info || plane >= info->num_planes)
+ return 0;
+
+ if (info->cpp[plane])
+ return info->cpp[plane] * width;
+
+ if (WARN_ON(!info->bytes_per_macropixel[plane] ||
+ !info->pixels_per_macropixel[plane])) {
+ struct drm_format_name_buf buf;
+
+ DRM_WARN("Either cpp or macro-pixel info should be valid: %s\n",
+ drm_get_format_name(info->format, &buf));
+ return 0;
+ }
+
+ return DIV_ROUND_UP(width * info->bytes_per_macropixel[plane],
+ info->pixels_per_macropixel[plane]);
+}
+EXPORT_SYMBOL(drm_format_plane_width_bytes);
diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
index ce59329..8158290 100644
--- a/include/drm/drm_fourcc.h
+++ b/include/drm/drm_fourcc.h
@@ -119,6 +119,8 @@ int drm_format_horz_chroma_subsampling(uint32_t format);
int drm_format_vert_chroma_subsampling(uint32_t format);
int drm_format_plane_width(int width, uint32_t format, int plane);
int drm_format_plane_height(int height, uint32_t format, int plane);
+int drm_format_plane_width_bytes(const struct drm_format_info *info,
+ int plane, int width);
const char *drm_get_format_name(uint32_t format, struct drm_format_name_buf *buf);
#endif /* __DRM_FOURCC_H__ */
--
2.7.4
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