Commit ba715932 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Sam Ravnborg
Browse files

drm/fb-helper: Add support for DRM_FORMAT_C[124] 



Add support for color-indexed frame buffer formats with two, four, and
sixteen colors to the DRM framebuffer helper functions:
  1. Add support for 1, 2, and 4 bits per pixel to the damage helper,
  2. For color-indexed modes, the length of the color bitfields must be
     set to the color depth, else the logo code may pick a logo with too
     many colors.  Drop the incorrect DAC width comment, which
     originates from the i915 driver.
  3. Accept C[124] modes when validating or filling in struct
     fb_var_screeninfo, and use the correct number of bits per pixel.
  4. Set the visual to FB_VISUAL_PSEUDOCOLOR for all color-indexed
     modes.

Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/db3e80b445df661ff0cd7e698507a8d24a4c867e.1657294931.git.geert@linux-m68k.org
parent e5bd7e3e

drivers/gpu/drm/drm_fb_helper.c

+75 −26
Original line number Diff line number Diff line
@@ -377,12 +377,31 @@ static void drm_fb_helper_damage_blit_real(struct drm_fb_helper *fb_helper, 
					   struct iosys_map *dst)

{

	struct drm_framebuffer *fb = fb_helper->fb;

	unsigned int cpp = fb->format->cpp[0];

	size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp;

	void *src = fb_helper->fbdev->screen_buffer + offset;

	size_t len = (clip->x2 - clip->x1) * cpp;

	size_t offset = clip->y1 * fb->pitches[0];

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

	unsigned int y;

	void *src;



	switch (drm_format_info_bpp(fb->format, 0)) {

	case 1:

		offset += clip->x1 / 8;

		len = DIV_ROUND_UP(len + clip->x1 % 8, 8);

		break;

	case 2:

		offset += clip->x1 / 4;

		len = DIV_ROUND_UP(len + clip->x1 % 4, 4);

		break;

	case 4:

		offset += clip->x1 / 2;

		len = DIV_ROUND_UP(len + clip->x1 % 2, 2);

		break;

	default:

		offset += clip->x1 * fb->format->cpp[0];

		len *= fb->format->cpp[0];

		break;

	}



	src = fb_helper->fbdev->screen_buffer + offset;

	iosys_map_incr(dst, offset); /* go to first pixel within clip rect */



	for (y = clip->y1; y < clip->y2; y++) {
@@ -1274,19 +1293,23 @@ static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1, 
}



static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,

					 u8 depth)

					 const struct drm_format_info *format)

{

	switch (depth) {

	case 8:

	u8 depth = format->depth;



	if (format->is_color_indexed) {

		var->red.offset = 0;

		var->green.offset = 0;

		var->blue.offset = 0;

		var->red.length = 8; /* 8bit DAC */

		var->green.length = 8;

		var->blue.length = 8;

		var->red.length = depth;

		var->green.length = depth;

		var->blue.length = depth;

		var->transp.offset = 0;

		var->transp.length = 0;

		break;

		return;

	}



	switch (depth) {

	case 15:

		var->red.offset = 10;

		var->green.offset = 5;
@@ -1341,7 +1364,9 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, 
{

	struct drm_fb_helper *fb_helper = info->par;

	struct drm_framebuffer *fb = fb_helper->fb;

	const struct drm_format_info *format = fb->format;

	struct drm_device *dev = fb_helper->dev;

	unsigned int bpp;



	if (in_dbg_master())

		return -EINVAL;
@@ -1351,22 +1376,33 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, 
		var->pixclock = 0;

	}



	if ((drm_format_info_block_width(fb->format, 0) > 1) ||

	    (drm_format_info_block_height(fb->format, 0) > 1))

	switch (format->format) {

	case DRM_FORMAT_C1:

	case DRM_FORMAT_C2:

	case DRM_FORMAT_C4:

		/* supported format with sub-byte pixels */

		break;



	default:

		if ((drm_format_info_block_width(format, 0) > 1) ||

		    (drm_format_info_block_height(format, 0) > 1))

			return -EINVAL;

		break;

	}



	/*

	 * Changes struct fb_var_screeninfo are currently not pushed back

	 * to KMS, hence fail if different settings are requested.

	 */

	if (var->bits_per_pixel > fb->format->cpp[0] * 8 ||

	bpp = drm_format_info_bpp(format, 0);

	if (var->bits_per_pixel > bpp ||

	    var->xres > fb->width || var->yres > fb->height ||

	    var->xres_virtual > fb->width || var->yres_virtual > fb->height) {

		drm_dbg_kms(dev, "fb requested width/height/bpp can't fit in current fb "

			  "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",

			  var->xres, var->yres, var->bits_per_pixel,

			  var->xres_virtual, var->yres_virtual,

			  fb->width, fb->height, fb->format->cpp[0] * 8);

			  fb->width, fb->height, bpp);

		return -EINVAL;

	}
@@ -1381,13 +1417,13 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, 
	    !var->blue.length    && !var->transp.length   &&

	    !var->red.msb_right  && !var->green.msb_right &&

	    !var->blue.msb_right && !var->transp.msb_right) {

		drm_fb_helper_fill_pixel_fmt(var, fb->format->depth);

		drm_fb_helper_fill_pixel_fmt(var, format);

	}



	/*

	 * Likewise, bits_per_pixel should be rounded up to a supported value.

	 */

	var->bits_per_pixel = fb->format->cpp[0] * 8;

	var->bits_per_pixel = bpp;



	/*

	 * drm fbdev emulation doesn't support changing the pixel format at all,
@@ -1723,11 +1759,11 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, 
}



static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,

				   uint32_t depth)

				   bool is_color_indexed)

{

	info->fix.type = FB_TYPE_PACKED_PIXELS;

	info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :

		FB_VISUAL_TRUECOLOR;

	info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR

					    : FB_VISUAL_TRUECOLOR;

	info->fix.mmio_start = 0;

	info->fix.mmio_len = 0;

	info->fix.type_aux = 0;
@@ -1744,19 +1780,31 @@ static void drm_fb_helper_fill_var(struct fb_info *info, 
				   uint32_t fb_width, uint32_t fb_height)

{

	struct drm_framebuffer *fb = fb_helper->fb;

	const struct drm_format_info *format = fb->format;



	switch (format->format) {

	case DRM_FORMAT_C1:

	case DRM_FORMAT_C2:

	case DRM_FORMAT_C4:

		/* supported format with sub-byte pixels */

		break;



	default:

		WARN_ON((drm_format_info_block_width(format, 0) > 1) ||

			(drm_format_info_block_height(format, 0) > 1));

		break;

	}



	WARN_ON((drm_format_info_block_width(fb->format, 0) > 1) ||

		(drm_format_info_block_height(fb->format, 0) > 1));

	info->pseudo_palette = fb_helper->pseudo_palette;

	info->var.xres_virtual = fb->width;

	info->var.yres_virtual = fb->height;

	info->var.bits_per_pixel = fb->format->cpp[0] * 8;

	info->var.bits_per_pixel = drm_format_info_bpp(format, 0);

	info->var.accel_flags = FB_ACCELF_TEXT;

	info->var.xoffset = 0;

	info->var.yoffset = 0;

	info->var.activate = FB_ACTIVATE_NOW;



	drm_fb_helper_fill_pixel_fmt(&info->var, fb->format->depth);

	drm_fb_helper_fill_pixel_fmt(&info->var, format);



	info->var.xres = fb_width;

	info->var.yres = fb_height;
@@ -1781,7 +1829,8 @@ void drm_fb_helper_fill_info(struct fb_info *info, 
{

	struct drm_framebuffer *fb = fb_helper->fb;



	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format->depth);

	drm_fb_helper_fill_fix(info, fb->pitches[0],

			       fb->format->is_color_indexed);

	drm_fb_helper_fill_var(info, fb_helper,

			       sizes->fb_width, sizes->fb_height);