Re: [PATCH] drm/format-helper: Add conversion from XRGB8888 to BGR888

[Aditya Garg]

> On 8 Jul 2024, at 1:00 PM, Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
> 
> Hi
> 
> Am 05.07.24 um 13:38 schrieb Aditya Garg:
>> From: Kerem Karabay <kekrby@xxxxxxxxx>
>> 
>> Add XRGB8888 emulation helper for devices that only support BGR888.
> 
> Nothing wrong with that, but it needs a caller. Do you have a driver that uses this routine?

Yes, we need this for the Touch Bar driver for T2 Macs


https://github.com/kekrby/linux-t2/commit/1f0b6c21c4d56f5be74c4d7d0665525862e307c3


> 
> Best regards
> Thomas
> 
>> 
>> Signed-off-by: Kerem Karabay <kekrby@xxxxxxxxx>
>> Signed-off-by: Aditya Garg <gargaditya08@xxxxxxxx>
>> ---
>>  drivers/gpu/drm/drm_format_helper.c           | 54 +++++++++++++
>>  .../gpu/drm/tests/drm_format_helper_test.c    | 81 +++++++++++++++++++
>>  include/drm/drm_format_helper.h               |  3 +
>>  3 files changed, 138 insertions(+)
>> 
>> diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
>> index b1be458ed..28c0e76a1 100644
>> --- a/drivers/gpu/drm/drm_format_helper.c
>> +++ b/drivers/gpu/drm/drm_format_helper.c
>> @@ -702,6 +702,57 @@ void drm_fb_xrgb8888_to_rgb888(struct iosys_map *dst, const unsigned int *dst_pi
>>  }
>>  EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888);
>>  +static void drm_fb_xrgb8888_to_bgr888_line(void *dbuf, const void *sbuf, unsigned int pixels)
>> +{
>> + u8 *dbuf8 = dbuf;
>> + const __le32 *sbuf32 = sbuf;
>> + unsigned int x;
>> + u32 pix;
>> +
>> + for (x = 0; x < pixels; x++) {
>> + pix = le32_to_cpu(sbuf32[x]);
>> + /* write red-green-blue to output in little endianness */
>> + *dbuf8++ = (pix & 0x00FF0000) >> 16;
>> + *dbuf8++ = (pix & 0x0000FF00) >> 8;
>> + *dbuf8++ = (pix & 0x000000FF) >> 0;
>> + }
>> +}
>> +
>> +/**
>> + * drm_fb_xrgb8888_to_bgr888 - Convert XRGB8888 to BGR888 clip buffer
>> + * @dst: Array of BGR888 destination buffers
>> + * @dst_pitch: Array of numbers of bytes between the start of two consecutive scanlines
>> + *             within @dst; can be NULL if scanlines are stored next to each other.
>> + * @src: Array of XRGB8888 source buffers
>> + * @fb: DRM framebuffer
>> + * @clip: Clip rectangle area to copy
>> + * @state: Transform and conversion state
>> + *
>> + * This function copies parts of a framebuffer to display memory and converts the
>> + * color format during the process. Destination and framebuffer formats must match. The
>> + * parameters @dst, @dst_pitch and @src refer to arrays. Each array must have at
>> + * least as many entries as there are planes in @fb's format. Each entry stores the
>> + * value for the format's respective color plane at the same index.
>> + *
>> + * This function does not apply clipping on @dst (i.e. the destination is at the
>> + * top-left corner).
>> + *
>> + * Drivers can use this function for BGR888 devices that don't natively
>> + * support XRGB8888.
>> + */
>> +void drm_fb_xrgb8888_to_bgr888(struct iosys_map *dst, const unsigned int *dst_pitch,
>> +        const struct iosys_map *src, const struct drm_framebuffer *fb,
>> +        const struct drm_rect *clip, struct drm_format_conv_state *state)
>> +{
>> + static const u8 dst_pixsize[DRM_FORMAT_MAX_PLANES] = {
>> + 3,
>> + };
>> +
>> + drm_fb_xfrm(dst, dst_pitch, dst_pixsize, src, fb, clip, false, state,
>> +     drm_fb_xrgb8888_to_bgr888_line);
>> +}
>> +EXPORT_SYMBOL(drm_fb_xrgb8888_to_bgr888);
>> +
>>  static void drm_fb_xrgb8888_to_argb8888_line(void *dbuf, const void *sbuf, unsigned int pixels)
>>  {
>>   __le32 *dbuf32 = dbuf;
>> @@ -1035,6 +1086,9 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d
>>   } else if (dst_format == DRM_FORMAT_RGB888) {
>>   drm_fb_xrgb8888_to_rgb888(dst, dst_pitch, src, fb, clip, state);
>>   return 0;
>> + } else if (dst_format == DRM_FORMAT_BGR888) {
>> + drm_fb_xrgb8888_to_bgr888(dst, dst_pitch, src, fb, clip, state);
>> + return 0;
>>   } else if (dst_format == DRM_FORMAT_ARGB8888) {
>>   drm_fb_xrgb8888_to_argb8888(dst, dst_pitch, src, fb, clip, state);
>>   return 0;
>> diff --git a/drivers/gpu/drm/tests/drm_format_helper_test.c b/drivers/gpu/drm/tests/drm_format_helper_test.c
>> index 08992636e..e54f0f6e7 100644
>> --- a/drivers/gpu/drm/tests/drm_format_helper_test.c
>> +++ b/drivers/gpu/drm/tests/drm_format_helper_test.c
>> @@ -60,6 +60,11 @@ struct convert_to_rgb888_result {
>>   const u8 expected[TEST_BUF_SIZE];
>>  };
>>  +struct convert_to_bgr888_result {
>> + unsigned int dst_pitch;
>> + const u8 expected[TEST_BUF_SIZE];
>> +};
>> +
>>  struct convert_to_argb8888_result {
>>   unsigned int dst_pitch;
>>   const u32 expected[TEST_BUF_SIZE];
>> @@ -107,6 +112,7 @@ struct convert_xrgb8888_case {
>>   struct convert_to_argb1555_result argb1555_result;
>>   struct convert_to_rgba5551_result rgba5551_result;
>>   struct convert_to_rgb888_result rgb888_result;
>> + struct convert_to_bgr888_result bgr888_result;
>>   struct convert_to_argb8888_result argb8888_result;
>>   struct convert_to_xrgb2101010_result xrgb2101010_result;
>>   struct convert_to_argb2101010_result argb2101010_result;
>> @@ -151,6 +157,10 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
>>   .dst_pitch = TEST_USE_DEFAULT_PITCH,
>>   .expected = { 0x00, 0x00, 0xFF },
>>   },
>> + .bgr888_result = {
>> + .dst_pitch = TEST_USE_DEFAULT_PITCH,
>> + .expected = { 0xFF, 0x00, 0x00 },
>> + },
>>   .argb8888_result = {
>>   .dst_pitch = TEST_USE_DEFAULT_PITCH,
>>   .expected = { 0xFFFF0000 },
>> @@ -217,6 +227,10 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
>>   .dst_pitch = TEST_USE_DEFAULT_PITCH,
>>   .expected = { 0x00, 0x00, 0xFF },
>>   },
>> + .bgr888_result = {
>> + .dst_pitch = TEST_USE_DEFAULT_PITCH,
>> + .expected = { 0xFF, 0x00, 0x00 },
>> + },
>>   .argb8888_result = {
>>   .dst_pitch = TEST_USE_DEFAULT_PITCH,
>>   .expected = { 0xFFFF0000 },
>> @@ -330,6 +344,15 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
>>   0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x00,
>>   },
>>   },
>> + .bgr888_result = {
>> + .dst_pitch = TEST_USE_DEFAULT_PITCH,
>> + .expected = {
>> + 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00,
>> + 0xFF, 0x00, 0x00, 0x00, 0xFF, 0x00,
>> + 0x00, 0x00, 0xFF, 0xFF, 0x00, 0xFF,
>> + 0xFF, 0xFF, 0x00, 0x00, 0xFF, 0xFF,
>> + },
>> + },
>>   .argb8888_result = {
>>   .dst_pitch = TEST_USE_DEFAULT_PITCH,
>>   .expected = {
>> @@ -468,6 +491,17 @@ static struct convert_xrgb8888_case convert_xrgb8888_cases[] = {
>>   0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
>>   },
>>   },
>> + .bgr888_result = {
>> + .dst_pitch = 15,
>> + .expected = {
>> + 0x0E, 0x44, 0x9C, 0x11, 0x4D, 0x05, 0xA8, 0xF3, 0x03,
>> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
>> + 0x6C, 0xF0, 0x73, 0x0E, 0x44, 0x9C, 0x11, 0x4D, 0x05,
>> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
>> + 0xA8, 0x03, 0x03, 0x6C, 0xF0, 0x73, 0x0E, 0x44, 0x9C,
>> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
>> + },
>> + },
>>   .argb8888_result = {
>>   .dst_pitch = 20,
>>   .expected = {
>> @@ -914,6 +948,52 @@ static void drm_test_fb_xrgb8888_to_rgb888(struct kunit *test)
>>   KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
>>  }
>>  +static void drm_test_fb_xrgb8888_to_bgr888(struct kunit *test)
>> +{
>> + const struct convert_xrgb8888_case *params = test->param_value;
>> + const struct convert_to_bgr888_result *result = &params->bgr888_result;
>> + size_t dst_size;
>> + u8 *buf = NULL;
>> + __le32 *xrgb8888 = NULL;
>> + struct iosys_map dst, src;
>> +
>> + struct drm_framebuffer fb = {
>> + .format = drm_format_info(DRM_FORMAT_XRGB8888),
>> + .pitches = { params->pitch, 0, 0 },
>> + };
>> +
>> + dst_size = conversion_buf_size(DRM_FORMAT_BGR888, result->dst_pitch,
>> +        &params->clip, 0);
>> + KUNIT_ASSERT_GT(test, dst_size, 0);
>> +
>> + buf = kunit_kzalloc(test, dst_size, GFP_KERNEL);
>> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf);
>> + iosys_map_set_vaddr(&dst, buf);
>> +
>> + xrgb8888 = cpubuf_to_le32(test, params->xrgb8888, TEST_BUF_SIZE);
>> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xrgb8888);
>> + iosys_map_set_vaddr(&src, xrgb8888);
>> +
>> + /*
>> +  * BGR888 expected results are already in little-endian
>> +  * order, so there's no need to convert the test output.
>> +  */
>> + drm_fb_xrgb8888_to_bgr888(&dst, &result->dst_pitch, &src, &fb, &params->clip,
>> +   &fmtcnv_state);
>> + KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
>> +
>> + buf = dst.vaddr; /* restore original value of buf */
>> + memset(buf, 0, dst_size);
>> +
>> + int blit_result = 0;
>> +
>> + blit_result = drm_fb_blit(&dst, &result->dst_pitch, DRM_FORMAT_BGR888, &src, &fb, &params->clip,
>> +   &fmtcnv_state);
>> +
>> + KUNIT_EXPECT_FALSE(test, blit_result);
>> + KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
>> +}
>> +
>>  static void drm_test_fb_xrgb8888_to_argb8888(struct kunit *test)
>>  {
>>   const struct convert_xrgb8888_case *params = test->param_value;
>> @@ -1851,6 +1931,7 @@ static struct kunit_case drm_format_helper_test_cases[] = {
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_argb1555, convert_xrgb8888_gen_params),
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgba5551, convert_xrgb8888_gen_params),
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_rgb888, convert_xrgb8888_gen_params),
>> + KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_bgr888, convert_xrgb8888_gen_params),
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_argb8888, convert_xrgb8888_gen_params),
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_xrgb2101010, convert_xrgb8888_gen_params),
>>   KUNIT_CASE_PARAM(drm_test_fb_xrgb8888_to_argb2101010, convert_xrgb8888_gen_params),
>> diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h
>> index f13b34e0b..b53cf85ca 100644
>> --- a/include/drm/drm_format_helper.h
>> +++ b/include/drm/drm_format_helper.h
>> @@ -95,6 +95,9 @@ void drm_fb_xrgb8888_to_rgba5551(struct iosys_map *dst, const unsigned int *dst_
>>  void drm_fb_xrgb8888_to_rgb888(struct iosys_map *dst, const unsigned int *dst_pitch,
>>          const struct iosys_map *src, const struct drm_framebuffer *fb,
>>          const struct drm_rect *clip, struct drm_format_conv_state *state);
>> +void drm_fb_xrgb8888_to_bgr888(struct iosys_map *dst, const unsigned int *dst_pitch,
>> +        const struct iosys_map *src, const struct drm_framebuffer *fb,
>> +        const struct drm_rect *clip, struct drm_format_conv_state *state);
>>  void drm_fb_xrgb8888_to_argb8888(struct iosys_map *dst, const unsigned int *dst_pitch,
>>    const struct iosys_map *src, const struct drm_framebuffer *fb,
>>    const struct drm_rect *clip, struct drm_format_conv_state *state);
> 
> -- 
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Frankenstrasse 146, 90461 Nuernberg, Germany
> GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
> HRB 36809 (AG Nuernberg)