Commit 877691b9 authored by Hector Martin's avatar Hector Martin Committed by Thomas Zimmermann
Browse files

drm/format-helper: Add drm_fb_xrgb8888_to_xrgb2101010_toio() 



Add XRGB8888 emulation support for devices that can only do XRGB2101010.

This is chiefly useful for simpledrm on Apple devices where the
bootloader-provided framebuffer is 10-bit.

Signed-off-by: default avatarHector Martin <marcan@marcan.st>
Reviewed-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211212062407.138309-3-marcan@marcan.st
parent 2f92ea21

drivers/gpu/drm/drm_format_helper.c

+64 −0
Original line number Diff line number Diff line
@@ -409,6 +409,61 @@ void drm_fb_xrgb8888_to_rgb888_toio(void __iomem *dst, unsigned int dst_pitch, 
}

EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_toio);



static void drm_fb_xrgb8888_to_xrgb2101010_line(u32 *dbuf, const u32 *sbuf,

						unsigned int pixels)

{

	unsigned int x;

	u32 val32;



	for (x = 0; x < pixels; x++) {

		val32 = ((sbuf[x] & 0x000000FF) << 2) |

			((sbuf[x] & 0x0000FF00) << 4) |

			((sbuf[x] & 0x00FF0000) << 6);

		*dbuf++ = val32 | ((val32 >> 8) & 0x00300C03);

	}

}



/**

 * drm_fb_xrgb8888_to_xrgb2101010_toio - Convert XRGB8888 to XRGB2101010 clip

 * buffer

 * @dst: XRGB2101010 destination buffer (iomem)

 * @dst_pitch: Number of bytes between two consecutive scanlines within dst

 * @vaddr: XRGB8888 source buffer

 * @fb: DRM framebuffer

 * @clip: Clip rectangle area to copy

 *

 * Drivers can use this function for XRGB2101010 devices that don't natively

 * support XRGB8888.

 */

void drm_fb_xrgb8888_to_xrgb2101010_toio(void __iomem *dst,

					 unsigned int dst_pitch, const void *vaddr,

					 const struct drm_framebuffer *fb,

					 const struct drm_rect *clip)

{

	size_t linepixels = clip->x2 - clip->x1;

	size_t dst_len = linepixels * sizeof(u32);

	unsigned int y, lines = clip->y2 - clip->y1;

	void *dbuf;



	if (!dst_pitch)

		dst_pitch = dst_len;



	dbuf = kmalloc(dst_len, GFP_KERNEL);

	if (!dbuf)

		return;



	vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));

	for (y = 0; y < lines; y++) {

		drm_fb_xrgb8888_to_xrgb2101010_line(dbuf, vaddr, linepixels);

		memcpy_toio(dst, dbuf, dst_len);

		vaddr += fb->pitches[0];

		dst += dst_pitch;

	}



	kfree(dbuf);

}

EXPORT_SYMBOL(drm_fb_xrgb8888_to_xrgb2101010_toio);



/**

 * drm_fb_xrgb8888_to_gray8 - Convert XRGB8888 to grayscale

 * @dst: 8-bit grayscale destination buffer
@@ -500,6 +555,10 @@ int drm_fb_blit_toio(void __iomem *dst, unsigned int dst_pitch, uint32_t dst_for 
		fb_format = DRM_FORMAT_XRGB8888;

	if (dst_format == DRM_FORMAT_ARGB8888)

		dst_format = DRM_FORMAT_XRGB8888;

	if (fb_format == DRM_FORMAT_ARGB2101010)

		fb_format = DRM_FORMAT_XRGB2101010;

	if (dst_format == DRM_FORMAT_ARGB2101010)

		dst_format = DRM_FORMAT_XRGB2101010;



	if (dst_format == fb_format) {

		drm_fb_memcpy_toio(dst, dst_pitch, vmap, fb, clip);
@@ -515,6 +574,11 @@ int drm_fb_blit_toio(void __iomem *dst, unsigned int dst_pitch, uint32_t dst_for 
			drm_fb_xrgb8888_to_rgb888_toio(dst, dst_pitch, vmap, fb, clip);

			return 0;

		}

	} else if (dst_format == DRM_FORMAT_XRGB2101010) {

		if (fb_format == DRM_FORMAT_XRGB8888) {

			drm_fb_xrgb8888_to_xrgb2101010_toio(dst, dst_pitch, vmap, fb, clip);

			return 0;

		}

	}



	return -EINVAL;

include/drm/drm_format_helper.h

+3 −0
Original line number Diff line number Diff line
@@ -33,6 +33,9 @@ void drm_fb_xrgb8888_to_rgb888(void *dst, unsigned int dst_pitch, const void *sr 
void drm_fb_xrgb8888_to_rgb888_toio(void __iomem *dst, unsigned int dst_pitch,

				    const void *vaddr, const struct drm_framebuffer *fb,

				    const struct drm_rect *clip);

void drm_fb_xrgb8888_to_xrgb2101010_toio(void __iomem *dst, unsigned int dst_pitch,

					 const void *vaddr, const struct drm_framebuffer *fb,

					 const struct drm_rect *clip);

void drm_fb_xrgb8888_to_gray8(void *dst, unsigned int dst_pitch, const void *vaddr,

			      const struct drm_framebuffer *fb, const struct drm_rect *clip);