From d405bc2c3d82126f58e143708af55105876cf6af Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Tue, 11 Oct 2022 17:07:12 +0200 Subject: [PATCH] drm/ofdrm: Support big-endian scanout buffers All DRM formats assume little-endian byte order. On big-endian systems, it is likely that the scanout buffer is in big endian as well. Update the format accordingly and add endianness conversion to the format-helper library. Also opt-in to allocated buffers in host format by default. Suggested-by: Geert Uytterhoeven Signed-off-by: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20221011150712.3928-6-tzimmermann@suse.de --- drivers/gpu/drm/drm_format_helper.c | 10 +++++++ drivers/gpu/drm/tiny/ofdrm.c | 55 +++++++++++++++++++++++++++++++++++-- 2 files changed, 63 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c index e2f7662..653a582 100644 --- a/drivers/gpu/drm/drm_format_helper.c +++ b/drivers/gpu/drm/drm_format_helper.c @@ -660,6 +660,11 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d drm_fb_xrgb8888_to_rgb565(dst, dst_pitch, src, fb, clip, false); return 0; } + } else if (dst_format == (DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN)) { + if (fb_format == DRM_FORMAT_RGB565) { + drm_fb_swab(dst, dst_pitch, src, fb, clip, false); + return 0; + } } else if (dst_format == DRM_FORMAT_RGB888) { if (fb_format == DRM_FORMAT_XRGB8888) { drm_fb_xrgb8888_to_rgb888(dst, dst_pitch, src, fb, clip); @@ -678,6 +683,11 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d drm_fb_xrgb8888_to_xrgb2101010(dst, dst_pitch, src, fb, clip); return 0; } + } else if (dst_format == DRM_FORMAT_BGRX8888) { + if (fb_format == DRM_FORMAT_XRGB8888) { + drm_fb_swab(dst, dst_pitch, src, fb, clip, false); + return 0; + } } drm_warn_once(fb->dev, "No conversion helper from %p4cc to %p4cc found.\n", diff --git a/drivers/gpu/drm/tiny/ofdrm.c b/drivers/gpu/drm/tiny/ofdrm.c index 3b0eaeb..0e1cc23 100644 --- a/drivers/gpu/drm/tiny/ofdrm.c +++ b/drivers/gpu/drm/tiny/ofdrm.c @@ -94,7 +94,7 @@ static int display_get_validated_int0(struct drm_device *dev, const char *name, } static const struct drm_format_info *display_get_validated_format(struct drm_device *dev, - u32 depth) + u32 depth, bool big_endian) { const struct drm_format_info *info; u32 format; @@ -115,6 +115,29 @@ static const struct drm_format_info *display_get_validated_format(struct drm_dev return ERR_PTR(-EINVAL); } + /* + * DRM formats assume little-endian byte order. Update the format + * if the scanout buffer uses big-endian ordering. + */ + if (big_endian) { + switch (format) { + case DRM_FORMAT_XRGB8888: + format = DRM_FORMAT_BGRX8888; + break; + case DRM_FORMAT_ARGB8888: + format = DRM_FORMAT_BGRA8888; + break; + case DRM_FORMAT_RGB565: + format = DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN; + break; + case DRM_FORMAT_XRGB1555: + format = DRM_FORMAT_XRGB1555 | DRM_FORMAT_BIG_ENDIAN; + break; + default: + break; + } + } + info = drm_format_info(format); if (!info) { drm_err(dev, "cannot find framebuffer format for depth %u\n", depth); @@ -134,6 +157,23 @@ static int display_read_u32_of(struct drm_device *dev, struct device_node *of_no return ret; } +static bool display_get_big_endian_of(struct drm_device *dev, struct device_node *of_node) +{ + bool big_endian; + +#ifdef __BIG_ENDIAN + big_endian = true; + if (of_get_property(of_node, "little-endian", NULL)) + big_endian = false; +#else + big_endian = false; + if (of_get_property(of_node, "big-endian", NULL)) + big_endian = true; +#endif + + return big_endian; +} + static int display_get_width_of(struct drm_device *dev, struct device_node *of_node) { u32 width; @@ -613,6 +653,7 @@ static void ofdrm_device_set_gamma_linear(struct ofdrm_device *odev, switch (format->format) { case DRM_FORMAT_RGB565: + case DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN: /* Use better interpolation, to take 32 values from 0 to 255 */ for (i = 0; i < OFDRM_GAMMA_LUT_SIZE / 8; i++) { unsigned char r = i * 8 + i / 4; @@ -631,6 +672,7 @@ static void ofdrm_device_set_gamma_linear(struct ofdrm_device *odev, } break; case DRM_FORMAT_XRGB8888: + case DRM_FORMAT_BGRX8888: for (i = 0; i < OFDRM_GAMMA_LUT_SIZE; i++) odev->funcs->cmap_write(odev, i, i, i, i); break; @@ -650,6 +692,7 @@ static void ofdrm_device_set_gamma(struct ofdrm_device *odev, switch (format->format) { case DRM_FORMAT_RGB565: + case DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN: /* Use better interpolation, to take 32 values from lut[0] to lut[255] */ for (i = 0; i < OFDRM_GAMMA_LUT_SIZE / 8; i++) { unsigned char r = lut[i * 8 + i / 4].red >> 8; @@ -668,6 +711,7 @@ static void ofdrm_device_set_gamma(struct ofdrm_device *odev, } break; case DRM_FORMAT_XRGB8888: + case DRM_FORMAT_BGRX8888: for (i = 0; i < OFDRM_GAMMA_LUT_SIZE; i++) { unsigned char r = lut[i].red >> 8; unsigned char g = lut[i].green >> 8; @@ -718,6 +762,9 @@ static const uint32_t ofdrm_primary_plane_formats[] = { DRM_FORMAT_RGB565, //DRM_FORMAT_XRGB1555, //DRM_FORMAT_C8, + /* Big-endian formats below */ + DRM_FORMAT_BGRX8888, + DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN, }; static const uint64_t ofdrm_primary_plane_format_modifiers[] = { @@ -1051,6 +1098,7 @@ static struct ofdrm_device *ofdrm_device_create(struct drm_driver *drv, struct ofdrm_device *odev; struct drm_device *dev; enum ofdrm_model model; + bool big_endian; int width, height, depth, linebytes; const struct drm_format_info *format; u64 address; @@ -1112,6 +1160,8 @@ static struct ofdrm_device *ofdrm_device_create(struct drm_driver *drv, break; } + big_endian = display_get_big_endian_of(dev, of_node); + width = display_get_width_of(dev, of_node); if (width < 0) return ERR_PTR(width); @@ -1125,7 +1175,7 @@ static struct ofdrm_device *ofdrm_device_create(struct drm_driver *drv, if (linebytes < 0) return ERR_PTR(linebytes); - format = display_get_validated_format(dev, depth); + format = display_get_validated_format(dev, depth, big_endian); if (IS_ERR(format)) return ERR_CAST(format); if (!linebytes) { @@ -1237,6 +1287,7 @@ static struct ofdrm_device *ofdrm_device_create(struct drm_driver *drv, dev->mode_config.preferred_depth = depth; break; } + dev->mode_config.quirk_addfb_prefer_host_byte_order = true; /* Primary plane */ -- 2.7.4