On Tue, 12 May 2020 at 12:34, Emil Velikov emil.l.velikov@gmail.com wrote:
Hi Rodrigo,
On Mon, 11 May 2020 at 12:55, Rodrigo Siqueira Rodrigo.Siqueira@amd.com wrote:
From: Rodrigo Siqueira rodrigosiqueiramelo@gmail.com
The compute_crc() function is responsible for calculating the framebuffer CRC value; due to the XRGB format, this function has to ignore the alpha channel during the CRC computation. Therefore, compute_crc() set zero to the alpha channel directly in the input framebuffer, which is not a problem since this function receives a copy of the original buffer. However, if we want to use this function in a context without a buffer copy, it will change the initial value. This patch makes compute_crc() calculate the CRC value without modifying the input framebuffer.
Signed-off-by: Rodrigo Siqueira rodrigosiqueiramelo@gmail.com
drivers/gpu/drm/vkms/vkms_composer.c | 31 +++++++++++++++++----------- 1 file changed, 19 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c index 258e659ecfba..686d25e7b01d 100644 --- a/drivers/gpu/drm/vkms/vkms_composer.c +++ b/drivers/gpu/drm/vkms/vkms_composer.c @@ -9,33 +9,40 @@
#include "vkms_drv.h"
+static u32 get_pixel_from_buffer(int x, int y, const u8 *buffer,
const struct vkms_composer *composer)+{
int src_offset = composer->offset + (y * composer->pitch)+ (x * composer->cpp);return *(u32 *)&buffer[src_offset];+}
/**
- compute_crc - Compute CRC value on output frame
- @vaddr_out: address to final framebuffer
*/
- @vaddr: address to final framebuffer
- @composer: framebuffer's metadata
- returns CRC value computed using crc32 on the visible portion of
- the final framebuffer at vaddr_out
-static uint32_t compute_crc(void *vaddr_out, struct vkms_composer *composer) +static uint32_t compute_crc(const u8 *vaddr,
const struct vkms_composer *composer){
int i, j, src_offset;
int x, y; int x_src = composer->src.x1 >> 16; int y_src = composer->src.y1 >> 16; int h_src = drm_rect_height(&composer->src) >> 16; int w_src = drm_rect_width(&composer->src) >> 16;
u32 crc = 0;
u32 crc = 0, pixel = 0;
for (i = y_src; i < y_src + h_src; ++i) {for (j = x_src; j < x_src + w_src; ++j) {src_offset = composer->offset+ (i * composer->pitch)+ (j * composer->cpp);
for (y = y_src; y < y_src + h_src; ++y) {for (x = x_src; x < x_src + w_src; ++x) { /* XRGB format ignores Alpha channel */
memset(vaddr_out + src_offset + 24, 0, 8);crc = crc32_le(crc, vaddr_out + src_offset,sizeof(u32));
pixel = get_pixel_from_buffer(x, y, vaddr, composer);bitmap_clear((void *)&pixel, 0, 8);crc = crc32_le(crc, (void *)&pixel, sizeof(u32)); } }IMHO using something like the following makes the code far simpler and clearer.
offset = composer->offset + (y_src * composer->pitch) + (x_src * composer->cpp);
for (i = 0; i < h_src; i++, offset += composer->pitch) { for (j = 0; j < w_src; j++, offset += composer->cpp) { pixel = get_pixel_from_buffer(vaddr, offset); crc = crc32_le(crc, &pixel, sizeof(u32); // cast should not be needed } }
With the bitmap_clear() and related comment moved into get_pixel_from_buffer().
If you fold the bitmap_clear() in get_pixel_from_buffer(), and drop the cast (unless I'm missing something and it's really needed) for crc32_le() this patch is:
Reviewed-by: Emil Velikov emil.l.velikov@gmail.com
I would suggest (but it's not a requirement) that you simplify the loop/offset calculation as separate patch in v5.
-Emil