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([2804:431:c7f5:7532:da7c:53df:9a5f:fa64]) by smtp.gmail.com with ESMTPSA id s10-20020a056830148a00b005ea12d6454bsm546284otq.38.2022.04.23.09.04.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 23 Apr 2022 09:04:45 -0700 (PDT) Message-ID: <6d9acb8b-8b1c-957e-8dd1-1d5ed99b08a6@gmail.com> Date: Sat, 23 Apr 2022 13:04:41 -0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH v5 6/9] drm: vkms: Refactor the plane composer to accept new formats Content-Language: en-US To: Pekka Paalanen References: <20220404204515.42144-1-igormtorrente@gmail.com> <20220404204515.42144-7-igormtorrente@gmail.com> <20220420153628.0a91fcb6@eldfell> From: Igor Torrente In-Reply-To: <20220420153628.0a91fcb6@eldfell> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: hamohammed.sa@gmail.com, tzimmermann@suse.de, rodrigosiqueiramelo@gmail.com, airlied@linux.ie, leandro.ribeiro@collabora.com, melissa.srw@gmail.com, dri-devel@lists.freedesktop.org, tales.aparecida@gmail.com, ~lkcamp/patches@lists.sr.ht Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Pekka, On 4/20/22 09:36, Pekka Paalanen wrote: > On Mon, 4 Apr 2022 17:45:12 -0300 > Igor Torrente wrote: > >> Currently the blend function only accepts XRGB_8888 and ARGB_8888 >> as a color input. >> >> This patch refactors all the functions related to the plane composition >> to overcome this limitation. >> >> A new internal format(`struct pixel`) is introduced to deal with all > > Hi, > > struct pixel_argb_u16 was added in the previous patch. I will fix it. Thanks! > >> possible inputs. It consists of 16 bits fields that represent each of >> the channels. >> >> The pixels blend is done using this internal format. And new handlers >> are being added to convert a specific format to/from this internal format. >> >> So the blend operation depends on these handlers to convert to this common >> format. The blended result, if necessary, is converted to the writeback >> buffer format. >> >> This patch introduces three major differences to the blend function. >> 1 - All the planes are blended at once. >> 2 - The blend calculus is done as per line instead of per pixel. >> 3 - It is responsible to calculates the CRC and writing the writeback >> buffer(if necessary). >> >> These changes allow us to allocate way less memory in the intermediate >> buffer to compute these operations. Because now we don't need to >> have the entire intermediate image lines at once, just one line is >> enough. >> >> | Memory consumption (output dimensions) | >> |:--------------------------------------:| >> | Current | This patch | >> |:------------------:|:-----------------:| >> | Width * Heigth | 2 * Width | >> >> Beyond memory, we also have a minor performance benefit from all >> these changes. Results running the IGT[1] test >> `igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times: >> >> | Frametime | >> |:------------------------------------------:| >> | Implementation | Current | This commit | >> |:---------------:|:---------:|:------------:| >> | frametime range | 9~22 ms | 5~17 ms | >> | Average | 11.4 ms | 7.8 ms | >> >> [1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4 >> >> V2: Improves the performance drastically, by performing the operations >> per-line and not per-pixel(Pekka Paalanen). >> Minor improvements(Pekka Paalanen). >> V3: Changes the code to blend the planes all at once. This improves >> performance, memory consumption, and removes much of the weirdness >> of the V2(Pekka Paalanen and me). >> Minor improvements(Pekka Paalanen and me). >> V4: Rebase the code and adapt it to the new NUM_OVERLAY_PLANES constant. >> V5: Minor checkpatch fixes and the removal of TO-DO item(Melissa Wen). >> Several security/robustness improvents(Pekka Paalanen). >> Removes check_planes_x_bounds function and allows partial >> partly off-screen(Pekka Paalanen). >> >> Signed-off-by: Igor Torrente >> --- >> Documentation/gpu/vkms.rst | 4 - >> drivers/gpu/drm/vkms/Makefile | 1 + >> drivers/gpu/drm/vkms/vkms_composer.c | 318 ++++++++++++-------------- >> drivers/gpu/drm/vkms/vkms_formats.c | 151 ++++++++++++ >> drivers/gpu/drm/vkms/vkms_formats.h | 12 + >> drivers/gpu/drm/vkms/vkms_plane.c | 3 + >> drivers/gpu/drm/vkms/vkms_writeback.c | 3 + >> 7 files changed, 311 insertions(+), 181 deletions(-) >> create mode 100644 drivers/gpu/drm/vkms/vkms_formats.c >> create mode 100644 drivers/gpu/drm/vkms/vkms_formats.h >> >> diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst >> index 973e2d43108b..a49e4ae92653 100644 >> --- a/Documentation/gpu/vkms.rst >> +++ b/Documentation/gpu/vkms.rst >> @@ -118,10 +118,6 @@ Add Plane Features >> >> There's lots of plane features we could add support for: >> >> -- Clearing primary plane: clear primary plane before plane composition (at the >> - start) for correctness of pixel blend ops. It also guarantees alpha channel >> - is cleared in the target buffer for stable crc. [Good to get started] >> - >> - ARGB format on primary plane: blend the primary plane into background with >> translucent alpha. >> >> diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile >> index 72f779cbfedd..1b28a6a32948 100644 >> --- a/drivers/gpu/drm/vkms/Makefile >> +++ b/drivers/gpu/drm/vkms/Makefile >> @@ -3,6 +3,7 @@ vkms-y := \ >> vkms_drv.o \ >> vkms_plane.o \ >> vkms_output.o \ >> + vkms_formats.o \ >> vkms_crtc.o \ >> vkms_composer.o \ >> vkms_writeback.o >> diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c >> index 95029d2ebcac..cf24015bf90f 100644 >> --- a/drivers/gpu/drm/vkms/vkms_composer.c >> +++ b/drivers/gpu/drm/vkms/vkms_composer.c > > (For this file, I have removed all the minus diff lines from below to > better see the new code.) > > >> @@ -7,204 +7,186 @@ >> #include >> #include >> #include >> +#include >> >> #include "vkms_drv.h" >> >> +static u16 pre_mul_blend_channel(u16 src, u16 dst, u16 alpha) >> { >> + u32 new_color; >> >> + new_color = (src * 0xffff + dst * (0xffff - alpha)); >> >> + return DIV_ROUND_CLOSEST(new_color, 0xffff); > > This looks good. > >> } >> >> /** >> + * pre_mul_alpha_blend - alpha blending equation >> + * @src_frame_info: source framebuffer's metadata >> + * @stage_buffer: The line with the pixels from src_plane >> + * @output_buffer: A line buffer that receives all the blends output >> * >> + * Using the information from the `frame_info`, this blends only the >> + * necessary pixels from the `stage_buffer` to the `output_buffer` >> + * using premultiplied blend formula. >> * >> + * The current DRM assumption is that pixel color values have been already >> + * pre-multiplied with the alpha channel values. See more >> + * drm_plane_create_blend_mode_property(). Also, this formula assumes a >> + * completely opaque background. >> */ >> +static void pre_mul_alpha_blend(struct vkms_frame_info *frame_info, >> + struct line_buffer *stage_buffer, >> + struct line_buffer *output_buffer) >> { >> + int x, x_dst = frame_info->dst.x1; >> + struct pixel_argb_u16 *out = output_buffer->pixels + x_dst; >> + struct pixel_argb_u16 *in = stage_buffer->pixels; >> + int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), >> + stage_buffer->n_pixels); >> + >> + for (x = 0; x < x_limit; x++) { >> + out[x].a = (u16)0xffff; >> + out[x].r = pre_mul_blend_channel(in[x].r, out[x].r, in[x].a); >> + out[x].g = pre_mul_blend_channel(in[x].g, out[x].g, in[x].a); >> + out[x].b = pre_mul_blend_channel(in[x].b, out[x].b, in[x].a); >> } >> } >> >> +static bool check_y_limit(struct vkms_frame_info *frame_info, int y) >> { >> + if (y >= frame_info->dst.y1 && y < frame_info->dst.y2) >> + return true; >> >> + return false; >> } >> >> /** >> + * @wb_frame_info: The writeback frame buffer metadata >> + * @crtc_state: The crtc state >> + * @crc32: The crc output of the final frame >> + * @output_buffer: A buffer of a row that will receive the result of the blend(s) >> + * @stage_buffer: The line with the pixels from plane being blend to the output >> * >> + * This function blends the pixels (Using the `pre_mul_alpha_blend`) >> + * from all planes, calculates the crc32 of the output from the former step, >> + * and, if necessary, convert and store the output to the writeback buffer. >> */ >> +static void blend(struct vkms_writeback_job *wb, >> + struct vkms_crtc_state *crtc_state, >> + u32 *crc32, struct line_buffer *stage_buffer, >> + struct line_buffer *output_buffer, s64 row_size) >> { >> + struct vkms_plane_state **plane = crtc_state->active_planes; >> + struct vkms_frame_info *primary_plane_info = plane[0]->frame_info; >> + u32 n_active_planes = crtc_state->num_active_planes; >> + >> + int y_dst = primary_plane_info->dst.y1; >> + int h_dst = drm_rect_height(&primary_plane_info->dst); >> + int y_limit = y_dst + h_dst; >> + int y, i; >> + >> + for (y = y_dst; y < y_limit; y++) { >> + plane[0]->format_func(output_buffer, primary_plane_info, y); > > This is a bad assumption, but the next patch removes the need for this > assumption. The primary plane may not be the bottom-most AFAIU. > Overlays below the primary exist on real hardware. > >> + >> + /* If there are other planes besides primary, we consider the active >> + * planes should be in z-order and compose them associatively: >> + * ((primary <- overlay) <- cursor) >> + */ >> + for (i = 1; i < n_active_planes; i++) { >> + if (!check_y_limit(plane[i]->frame_info, y)) >> + continue; >> + >> + plane[i]->format_func(stage_buffer, plane[i]->frame_info, y); >> + pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer, >> + output_buffer); >> + } >> >> + *crc32 = crc32_le(*crc32, (void *)output_buffer->pixels, row_size); >> >> + if (wb) >> + wb->format_func(&wb->frame_info, output_buffer, y); >> } >> } >> >> +static int check_format_funcs(struct vkms_crtc_state *crtc_state, >> + struct vkms_writeback_job *active_wb) >> { >> + struct vkms_plane_state **planes = crtc_state->active_planes; >> + u32 n_active_planes = crtc_state->num_active_planes; >> + int i; >> >> + for (i = 0; i < n_active_planes; i++) >> + if (!planes[i]->format_func) >> + return -1; >> >> + if (active_wb && !active_wb->format_func) >> + return -1; >> >> + return 0; >> } >> >> +static int compose_active_planes(struct vkms_writeback_job *active_wb, >> + struct vkms_crtc_state *crtc_state, >> + u32 *crc32) >> { >> + int line_width, ret = 0, pixel_size = sizeof(struct pixel_argb_u16); >> + struct vkms_frame_info *primary_plane_info = NULL; >> + struct line_buffer output_buffer, stage_buffer; >> + struct vkms_plane_state *act_plane = NULL; >> + u32 wb_format; >> >> + if (WARN_ON(pixel_size != 8)) > > Isn't there a compile-time assert macro for this? Having to actually > run VKMS to check for this reduces the chances of finding it early. > What's the reason for this check anyway? > >> + return -EINVAL; >> + >> + if (crtc_state->num_active_planes >= 1) { >> + act_plane = crtc_state->active_planes[0]; >> + if (act_plane->base.base.plane->type == DRM_PLANE_TYPE_PRIMARY) >> + primary_plane_info = act_plane->frame_info; > > After the next patch, do you even need the primary plane for anything > specifically? There is the map_is_null check below, but that should be > done on all planes in the array, right? > > I suspect the next patch, or another patch in this series, should just > delete this chunk. > >> } >> >> + if (!primary_plane_info) >> + return -EINVAL; >> + >> if (WARN_ON(dma_buf_map_is_null(&primary_plane_info->map[0]))) >> return -EINVAL; >> >> + if (WARN_ON(check_format_funcs(crtc_state, active_wb))) >> + return -EINVAL; >> >> + line_width = drm_rect_width(&primary_plane_info->dst); >> + stage_buffer.n_pixels = line_width; >> + output_buffer.n_pixels = line_width; >> >> + stage_buffer.pixels = kvmalloc(line_width * pixel_size, GFP_KERNEL); >> + if (!stage_buffer.pixels) { >> + DRM_ERROR("Cannot allocate memory for the output line buffer"); >> + return -ENOMEM; >> + } >> >> + output_buffer.pixels = kvmalloc(line_width * pixel_size, GFP_KERNEL); >> + if (!output_buffer.pixels) { >> + DRM_ERROR("Cannot allocate memory for intermediate line buffer"); >> + ret = -ENOMEM; >> + goto free_stage_buffer; >> + } >> + >> + if (active_wb) { >> + struct vkms_frame_info *wb_frame_info = &active_wb->frame_info; >> + >> + wb_format = wb_frame_info->fb->format->format; > > I don't see wb_format being used, is it? This is probably a leftover from the last versions. Thanks for catching it. > >> + wb_frame_info->src = primary_plane_info->src; >> + wb_frame_info->dst = primary_plane_info->dst; >> + } >> + >> + blend(active_wb, crtc_state, crc32, &stage_buffer, >> + &output_buffer, (s64)line_width * pixel_size); > > What's the (s64) doing here? > > Are byte sizes not usually expressed with size_t or ssize_t types, or > is the kernel convention to use u64 and s64? > > This makes me suspect that pixel_offset() and friends in vkms_format.c > are going to need fixing as well. int type overflows at 2G. Yeah, I should be using size_t in all these places. > >> + >> + kvfree(output_buffer.pixels); >> +free_stage_buffer: >> + kvfree(stage_buffer.pixels); >> +can >> + return ret; >> } >> >> /** >> @@ -222,13 +204,11 @@ void vkms_composer_worker(struct work_struct *work) >> struct vkms_crtc_state, >> composer_work); >> struct drm_crtc *crtc = crtc_state->base.crtc; >> + struct vkms_writeback_job *active_wb = crtc_state->active_writeback; >> struct vkms_output *out = drm_crtc_to_vkms_output(crtc); >> bool crc_pending, wb_pending; >> u64 frame_start, frame_end; >> + u32 crc32 = 0; >> int ret; >> >> spin_lock_irq(&out->composer_lock); >> @@ -248,35 +228,19 @@ void vkms_composer_worker(struct work_struct *work) >> if (!crc_pending) >> return; >> >> if (wb_pending) >> + ret = compose_active_planes(active_wb, crtc_state, &crc32); >> + else >> + ret = compose_active_planes(NULL, crtc_state, &crc32); >> >> + if (ret) >> return; >> >> if (wb_pending) { >> drm_writeback_signal_completion(&out->wb_connector, 0); >> spin_lock_irq(&out->composer_lock); >> crtc_state->wb_pending = false; >> spin_unlock_irq(&out->composer_lock); >> } >> >> /* >> diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c >> new file mode 100644 >> index 000000000000..931a61405d6a >> --- /dev/null >> +++ b/drivers/gpu/drm/vkms/vkms_formats.c >> @@ -0,0 +1,151 @@ >> +// SPDX-License-Identifier: GPL-2.0+ >> + >> +#include >> +#include >> + >> +#include "vkms_formats.h" >> + >> +static int pixel_offset(const struct vkms_frame_info *frame_info, int x, int y) >> +{ >> + return frame_info->offset + (y * frame_info->pitch) >> + + (x * frame_info->cpp); >> +} >> + >> +/* >> + * packed_pixels_addr - Get the pointer to pixel of a given pair of coordinates >> + * >> + * @frame_info: Buffer metadata >> + * @x: The x(width) coordinate of the 2D buffer >> + * @y: The y(Heigth) coordinate of the 2D buffercan >> + * >> + * 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). >> + */ >> +static void *packed_pixels_addr(const struct vkms_frame_info *frame_info, >> + int x, int y) >> +{ >> + int offset = pixel_offset(frame_info, x, y); >> + >> + return (u8 *)frame_info->map[0].vaddr + offset; >> +} >> + >> +static void *get_packed_src_addr(const struct vkms_frame_info *frame_info, int y) >> +{ >> + int x_src = frame_info->src.x1 >> 16; >> + int y_src = y - frame_info->dst.y1 + (frame_info->src.y1 >> 16); >> + >> + return packed_pixels_addr(frame_info, x_src, y_src); >> +} >> + >> +static void ARGB8888_to_argb_u16(struct line_buffer *stage_buffer, >> + const struct vkms_frame_info *frame_info, int y) >> +{ >> + struct pixel_argb_u16 *out_pixels = stage_buffer->pixels; >> + u8 *src_pixels = get_packed_src_addr(frame_info, y); >> + int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), >> + stage_buffer->n_pixels); >> + >> + for (x = 0; x < x_limit; x++, src_pixels += 4) { >> + /* >> + * The 257 is the "conversion ratio". This number is obtained by the >> + * (2^16 - 1) / (2^8 - 1) division. Which, in this case, tries to get >> + * the best color value in a pixel format with more possibilities. >> + * A similar idea applies to others RGB color conversions. >> + */ >> + out_pixels[x].a = (u16)src_pixels[3] * 257; >> + out_pixels[x].r = (u16)src_pixels[2] * 257; >> + out_pixels[x].g = (u16)src_pixels[1] * 257; >> + out_pixels[x].b = (u16)src_pixels[0] * 257; >> + } >> +} >> + >> +static void XRGB8888_to_argb_u16(struct line_buffer *stage_buffer, >> + const struct vkms_frame_info *frame_info, int y) >> +{ >> + struct pixel_argb_u16 *out_pixels = stage_buffer->pixels; >> + u8 *src_pixels = get_packed_src_addr(frame_info, y); >> + int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst), >> + stage_buffer->n_pixels); >> + >> + for (x = 0; x < x_limit; x++, src_pixels += 4) { >> + out_pixels[x].a = (u16)0xffff; >> + out_pixels[x].r = (u16)src_pixels[2] * 257; >> + out_pixels[x].g = (u16)src_pixels[1] * 257; >> + out_pixels[x].b = (u16)src_pixels[0] * 257; >> + } >> +} >> + >> +/* >> + * The following functions take an line of argb_u16 pixels from the >> + * src_buffer, convert them to a specific format, and store them in the >> + * destination. >> + * >> + * They are used in the `compose_active_planes` to convert and store a line >> + * from the src_buffer to the writeback buffer. >> + */ >> +static void argb_u16_to_ARGB8888(struct vkms_frame_info *frame_info, >> + const struct line_buffer *src_buffer, int y) >> +{ >> + int x, x_dst = frame_info->dst.x1; >> + u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, 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); >> + >> + for (x = 0; x < x_limit; x++, dst_pixels += 4) { >> + /* >> + * This sequence below is important because the format's byte order is >> + * in little-endian. In the case of the ARGB8888 the memory is >> + * organized this way: >> + * >> + * | Addr | = blue channel >> + * | Addr + 1 | = green channel >> + * | Addr + 2 | = Red channel >> + * | Addr + 3 | = Alpha channel >> + */ >> + dst_pixels[3] = DIV_ROUND_CLOSEST(in_pixels[x].a, 257); >> + dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixels[x].r, 257); >> + dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixels[x].g, 257); >> + dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixels[x].b, 257); >> + } >> +} >> + >> +static void argb_u16_to_XRGB8888(struct vkms_frame_info *frame_info, >> + const struct line_buffer *src_buffer, int y) >> +{ >> + int x, x_dst = frame_info->dst.x1; >> + u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, 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); >> + >> + for (x = 0; x < x_limit; x++, dst_pixels += 4) { >> + dst_pixels[3] = (u8)0xff; > > When writing to XRGB, it's not necessary to ensure the X channel has > any sensible value. Anyone reading from XRGB must ignore that value > anyway. So why not write something wacky here, like 0xa1, that is far > enough from both 0x00 or 0xff to not be confused with them even > visually? Also not 0x7f or 0x80 which are close to half of 0xff. > > Or, you could save a whole function and just use argb_u16_to_ARGBxxxx() > instead, even for XRGB destination. Right. Maybe I could just leave the channel untouched. > >> + dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixels[x].r, 257); >> + dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixels[x].g, 257); >> + dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixels[x].b, 257); >> + } >> +} >> + >> +plane_format_transform_func get_plane_fmt_transform_function(u32 format) >> +{ >> + if (format == DRM_FORMAT_ARGB8888) >> + return &ARGB8888_to_argb_u16; >> + else if (format == DRM_FORMAT_XRGB8888) >> + return &XRGB8888_to_argb_u16; >> + else >> + return NULL; > > This works for now, but when more formats are added, I'd think a switch > statement would look better. ok. > >> +} >> + >> +wb_format_transform_func get_wb_fmt_transform_function(u32 format) >> +{ >> + if (format == DRM_FORMAT_ARGB8888) >> + return &argb_u16_to_ARGB8888; >> + else if (format == DRM_FORMAT_XRGB8888) >> + return &argb_u16_to_XRGB8888; >> + else >> + return NULL; >> +} >> diff --git a/drivers/gpu/drm/vkms/vkms_formats.h b/drivers/gpu/drm/vkms/vkms_formats.h >> new file mode 100644 >> index 000000000000..adc5a17b9584 >> --- /dev/null >> +++ b/drivers/gpu/drm/vkms/vkms_formats.h >> @@ -0,0 +1,12 @@ >> +// SPDX-License-Identifier: GPL-2.0+ >> + >> +#ifndef _VKMS_FORMATS_H_ >> +#define _VKMS_FORMATS_H_ >> + >> +#include "vkms_drv.h" >> + >> +plane_format_transform_func get_plane_fmt_transform_function(u32 format); >> + >> +wb_format_transform_func get_wb_fmt_transform_function(u32 format); > > This is good, exposing only what is necessary. > > > Thanks, > pq > >> + >> +#endif /* _VKMS_FORMATS_H_ */ >> diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c >> index 28752af0118c..798243837fd0 100644 >> --- a/drivers/gpu/drm/vkms/vkms_plane.c >> +++ b/drivers/gpu/drm/vkms/vkms_plane.c >> @@ -10,6 +10,7 @@ >> #include >> >> #include "vkms_drv.h" >> +#include "vkms_formats.h" >> >> static const u32 vkms_formats[] = { >> DRM_FORMAT_XRGB8888, >> @@ -100,6 +101,7 @@ static void vkms_plane_atomic_update(struct drm_plane *plane, >> struct drm_shadow_plane_state *shadow_plane_state; >> struct drm_framebuffer *fb = new_state->fb; >> struct vkms_frame_info *frame_info; >> + u32 fmt = fb->format->format; >> >> if (!new_state->crtc || !fb) >> return; >> @@ -116,6 +118,7 @@ static void vkms_plane_atomic_update(struct drm_plane *plane, >> frame_info->offset = fb->offsets[0]; >> frame_info->pitch = fb->pitches[0]; >> frame_info->cpp = fb->format->cpp[0]; >> + vkms_plane_state->format_func = get_plane_fmt_transform_function(fmt); >> } >> >> static int vkms_plane_atomic_check(struct drm_plane *plane, >> diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c >> index ad4bb1fb37ca..97f71e784bbf 100644 >> --- a/drivers/gpu/drm/vkms/vkms_writeback.c >> +++ b/drivers/gpu/drm/vkms/vkms_writeback.c >> @@ -11,6 +11,7 @@ >> #include >> >> #include "vkms_drv.h" >> +#include "vkms_formats.h" >> >> static const u32 vkms_wb_formats[] = { >> DRM_FORMAT_XRGB8888, >> @@ -123,6 +124,7 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn, >> struct drm_framebuffer *fb = connector_state->writeback_job->fb; >> struct vkms_writeback_job *active_wb; >> struct vkms_frame_info *wb_frame_info; >> + u32 wb_format = fb->format->format; >> >> if (!conn_state) >> return; >> @@ -140,6 +142,7 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn, >> crtc_state->wb_pending = true; >> spin_unlock_irq(&output->composer_lock); >> drm_writeback_queue_job(wb_conn, connector_state); >> + active_wb->format_func = get_wb_fmt_transform_function(wb_format); >> } >> >> static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = { >