[PATCH v8 07/17] drm/vkms: Update pixels accessor to support packed and multi-plane formats.
Louis Chauvet
louis.chauvet at bootlin.com
Thu May 16 13:04:52 UTC 2024
Introduce the usage of block_h/block_w to compute the offset and the
pointer of a pixel. The previous implementation was specialized for
planes with block_h == block_w == 1. To avoid confusion and allow easier
implementation of tiled formats. It also remove the usage of the
deprecated format field `cpp`.
Introduce the plane_index parameter to get an offset/pointer on a
different plane.
Signed-off-by: Louis Chauvet <louis.chauvet at bootlin.com>
---
drivers/gpu/drm/vkms/vkms_formats.c | 112 ++++++++++++++++++++++++++++--------
1 file changed, 89 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
index 69cf9733fec5..3874c8fe4f84 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.c
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -10,22 +10,45 @@
#include "vkms_formats.h"
/**
- * pixel_offset() - Get the offset of the pixel at coordinates x/y in the first plane
+ * packed_pixels_offset() - Get the offset of the block containing the pixel at coordinates x/y
*
* @frame_info: Buffer metadata
* @x: The x coordinate of the wanted pixel in the buffer
* @y: The y coordinate of the wanted pixel in the buffer
+ * @plane_index: The index of the plane to use
+ * @offset: The returned offset inside the buffer of the block
+ * @rem_x, at rem_y: The returned coordinate of the requested pixel in the block
*
- * The caller must ensure that the framebuffer associated with this request uses a pixel format
- * where block_h == block_w == 1.
- * If this requirement is not fulfilled, the resulting offset can point to an other pixel or
- * outside of the buffer.
+ * As some pixel formats store multiple pixels in a block (DRM_FORMAT_R* for example), some
+ * pixels are not individually addressable. This function return 3 values: the offset of the
+ * whole block, and the coordinate of the requested pixel inside this block.
+ * For example, if the format is DRM_FORMAT_R1 and the requested coordinate is 13,5, the offset
+ * will point to the byte 5*pitches + 13/8 (second byte of the 5th line), and the rem_x/rem_y
+ * coordinates will be (13 % 8, 5 % 1) = (5, 0)
+ *
+ * With this function, the caller just have to extract the correct pixel from the block.
*/
-static size_t pixel_offset(const struct vkms_frame_info *frame_info, int x, int y)
+static void packed_pixels_offset(const struct vkms_frame_info *frame_info, int x, int y,
+ int plane_index, int *offset, int *rem_x, int *rem_y)
{
struct drm_framebuffer *fb = frame_info->fb;
+ const struct drm_format_info *format = frame_info->fb->format;
+ /* Directly using x and y to multiply pitches and format->ccp is not sufficient because
+ * in some formats a block can represent multiple pixels.
+ *
+ * Dividing x and y by the block size allows to extract the correct offset of the block
+ * containing the pixel.
+ */
- return fb->offsets[0] + (y * fb->pitches[0]) + (x * fb->format->cpp[0]);
+ int block_x = x / drm_format_info_block_width(format, plane_index);
+ int block_y = y / drm_format_info_block_height(format, plane_index);
+ int block_pitch = fb->pitches[plane_index] * drm_format_info_block_height(format,
+ plane_index);
+ *rem_x = x % drm_format_info_block_width(format, plane_index);
+ *rem_y = y % drm_format_info_block_height(format, plane_index);
+ *offset = fb->offsets[plane_index] +
+ block_y * block_pitch +
+ block_x * format->char_per_block[plane_index];
}
/**
@@ -35,30 +58,70 @@ static size_t pixel_offset(const struct vkms_frame_info *frame_info, int x, int
* @frame_info: Buffer metadata
* @x: The x (width) coordinate inside the plane
* @y: The y (height) coordinate inside the plane
+ * @plane_index: The index of the plane
+ * @addr: The returned pointer
+ * @rem_x, at rem_y: The returned coordinate of the requested pixel in the block
*
- * Takes the information stored in the frame_info, a pair of coordinates, and
- * returns the address of the first color channel.
- * This function assumes the channels are packed together, i.e. a color channel
- * comes immediately after another in the memory. And therefore, this function
- * doesn't work for YUV with chroma subsampling (e.g. YUV420 and NV21).
+ * Takes the information stored in the frame_info, a pair of coordinates, and returns the address
+ * of the block containing this pixel and the pixel position inside this block.
*
- * The caller must ensure that the framebuffer associated with this request uses a pixel format
- * where block_h == block_w == 1, otherwise the returned pointer can be outside the buffer.
+ * See @packed_pixel_offset for details about rem_x/rem_y behavior.
*/
-static void *packed_pixels_addr(const struct vkms_frame_info *frame_info,
- int x, int y)
+static void packed_pixels_addr(const struct vkms_frame_info *frame_info,
+ int x, int y, int plane_index, u8 **addr, int *rem_x,
+ int *rem_y)
{
- size_t offset = pixel_offset(frame_info, x, y);
+ int offset;
- return (u8 *)frame_info->map[0].vaddr + offset;
+ packed_pixels_offset(frame_info, x, y, plane_index, &offset, rem_x, rem_y);
+ *addr = (u8 *)frame_info->map[0].vaddr + offset;
}
-static void *get_packed_src_addr(const struct vkms_frame_info *frame_info, int y)
+/**
+ * packed_pixels_addr_1x1() - Get the pointer to the block containing the pixel at the given
+ * coordinates
+ *
+ * @frame_info: Buffer metadata
+ * @x: The x (width) coordinate inside the plane
+ * @y: The y (height) coordinate inside the plane
+ * @plane_index: The index of the plane
+ * @addr: The returned pointer
+ *
+ * This function can only be used with format where block_h == block_w == 1.
+ */
+static void packed_pixels_addr_1x1(const struct vkms_frame_info *frame_info,
+ int x, int y, int plane_index, u8 **addr)
+{
+ int offset, rem_x, rem_y;
+
+ WARN_ONCE(drm_format_info_block_width(frame_info->fb->format,
+ plane_index) != 1,
+ "%s() only support formats with block_w == 1", __func__);
+ WARN_ONCE(drm_format_info_block_height(frame_info->fb->format,
+ plane_index) != 1,
+ "%s() only support formats with block_h == 1", __func__);
+
+ packed_pixels_offset(frame_info, x, y, plane_index, &offset, &rem_x,
+ &rem_y);
+ *addr = (u8 *)frame_info->map[0].vaddr + offset;
+}
+
+static void *get_packed_src_addr(const struct vkms_frame_info *frame_info, int y,
+ int plane_index)
{
int x_src = frame_info->src.x1 >> 16;
int y_src = y - frame_info->rotated.y1 + (frame_info->src.y1 >> 16);
+ u8 *addr;
+ int rem_x, rem_y;
+
+ WARN_ONCE(drm_format_info_block_width(frame_info->fb->format, plane_index) != 1,
+ "%s() only support formats with block_w == 1", __func__);
+ WARN_ONCE(drm_format_info_block_height(frame_info->fb->format, plane_index) != 1,
+ "%s() only support formats with block_h == 1", __func__);
- return packed_pixels_addr(frame_info, x_src, y_src);
+ packed_pixels_addr(frame_info, x_src, y_src, plane_index, &addr, &rem_x, &rem_y);
+
+ return addr;
}
static int get_x_position(const struct vkms_frame_info *frame_info, int limit, int x)
@@ -167,14 +230,14 @@ void vkms_compose_row(struct line_buffer *stage_buffer, struct vkms_plane_state
{
struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
struct vkms_frame_info *frame_info = plane->frame_info;
- u8 *src_pixels = get_packed_src_addr(frame_info, y);
+ u8 *src_pixels = get_packed_src_addr(frame_info, y, 0);
int limit = min_t(size_t, drm_rect_width(&frame_info->dst), stage_buffer->n_pixels);
for (size_t x = 0; x < limit; x++, src_pixels += frame_info->fb->format->cpp[0]) {
int x_pos = get_x_position(frame_info, limit, x);
if (drm_rotation_90_or_270(frame_info->rotation))
- src_pixels = get_packed_src_addr(frame_info, x + frame_info->rotated.y1)
+ src_pixels = get_packed_src_addr(frame_info, x + frame_info->rotated.y1, 0)
+ frame_info->fb->format->cpp[0] * y;
plane->pixel_read(src_pixels, &out_pixels[x_pos]);
@@ -275,7 +338,10 @@ void vkms_writeback_row(struct vkms_writeback_job *wb,
{
struct vkms_frame_info *frame_info = &wb->wb_frame_info;
int x_dst = frame_info->dst.x1;
- u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
+ u8 *dst_pixels;
+ int rem_x, rem_y;
+
+ packed_pixels_addr(frame_info, x_dst, y, 0, &dst_pixels, &rem_x, &rem_y);
struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), src_buffer->n_pixels);
--
2.43.2
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