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

[Thomas Zimmermann]

Hi

Am 09.07.24 um 08:10 schrieb Aditya Garg:
> Hi Thomas
>
> I found upstreamed drivers which may be using this routine.
>
> https://elixir.bootlin.com/linux/latest/A/ident/DRM_FORMAT_BGR888

These drivers support BGR888 in hardware. They don't convert pixel 
format on the fly.

> I guess the same logic was used to upstream all these:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm/drm_format_helper.c?h=v6.10-rc7&id=10cd592e639edcea50d781a07edcf3470d1f222e
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm/drm_format_helper.c?h=v6.10-rc7&id=56119bfb39142090fb84ac08a3f14dd48410e961
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm/drm_format_helper.c?h=v6.10-rc7&id=175073d694cd9db4c4ca97c978a447acc6b5cb33
>
>
> My apologies if I am wrong somewhere.

No worries.

Best regards
Thomas

> ________________________________________
> From: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Sent: 08 July 2024 13:00
> To: Aditya Garg; maarten.lankhorst@xxxxxxxxxxxxxxx; mripard@xxxxxxxxxx; airlied@xxxxxxxxx; daniel@xxxxxxxx
> Cc: Orlando Chamberlain; Kerem Karabay; dri-devel@xxxxxxxxxxxxxxxxxxxxx; Linux Kernel Mailing List
> Subject: Re: [PATCH] drm/format-helper: Add conversion from XRGB8888 to BGR888
>
> 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?
>
> 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)

--
--
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)