[PATCH v7 1/4] drm/panic: Add integer scaling to blit()

[Thomas Zimmermann]

Am 22.08.24 um 09:33 schrieb Jocelyn Falempe:
> Add a parameter to the blit function, to upscale the image.
> This is necessary to draw a QR code, otherwise, the pixels are
> usually too small to be readable by most QR code reader.
> It can also be used later for drawing fonts on high DPI display.
>
> Signed-off-by: Jocelyn Falempe <jfalempe at redhat.com>

Reviewed-by: Thomas Zimmermann <tzimmermann at suse.de>

> ---
>   drivers/gpu/drm/drm_panic.c | 33 +++++++++++++++++++--------------
>   1 file changed, 19 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
> index eff4598e2fc73..0a047152f88b8 100644
> --- a/drivers/gpu/drm/drm_panic.c
> +++ b/drivers/gpu/drm/drm_panic.c
> @@ -257,20 +257,20 @@ static bool drm_panic_is_pixel_fg(const u8 *sbuf8, unsigned int spitch, int x, i
>   static void drm_panic_blit16(struct iosys_map *dmap, unsigned int dpitch,
>   			     const u8 *sbuf8, unsigned int spitch,
>   			     unsigned int height, unsigned int width,
> -			     u16 fg16)
> +			     unsigned int scale, u16 fg16)
>   {
>   	unsigned int y, x;
>   
>   	for (y = 0; y < height; y++)
>   		for (x = 0; x < width; x++)
> -			if (drm_panic_is_pixel_fg(sbuf8, spitch, x, y))
> +			if (drm_panic_is_pixel_fg(sbuf8, spitch, x / scale, y / scale))
>   				iosys_map_wr(dmap, y * dpitch + x * sizeof(u16), u16, fg16);
>   }
>   
>   static void drm_panic_blit24(struct iosys_map *dmap, unsigned int dpitch,
>   			     const u8 *sbuf8, unsigned int spitch,
>   			     unsigned int height, unsigned int width,
> -			     u32 fg32)
> +			     unsigned int scale, u32 fg32)
>   {
>   	unsigned int y, x;
>   
> @@ -278,7 +278,7 @@ static void drm_panic_blit24(struct iosys_map *dmap, unsigned int dpitch,
>   		for (x = 0; x < width; x++) {
>   			u32 off = y * dpitch + x * 3;
>   
> -			if (drm_panic_is_pixel_fg(sbuf8, spitch, x, y)) {
> +			if (drm_panic_is_pixel_fg(sbuf8, spitch, x / scale, y / scale)) {
>   				/* write blue-green-red to output in little endianness */
>   				iosys_map_wr(dmap, off, u8, (fg32 & 0x000000FF) >> 0);
>   				iosys_map_wr(dmap, off + 1, u8, (fg32 & 0x0000FF00) >> 8);
> @@ -291,24 +291,25 @@ static void drm_panic_blit24(struct iosys_map *dmap, unsigned int dpitch,
>   static void drm_panic_blit32(struct iosys_map *dmap, unsigned int dpitch,
>   			     const u8 *sbuf8, unsigned int spitch,
>   			     unsigned int height, unsigned int width,
> -			     u32 fg32)
> +			     unsigned int scale, u32 fg32)
>   {
>   	unsigned int y, x;
>   
>   	for (y = 0; y < height; y++)
>   		for (x = 0; x < width; x++)
> -			if (drm_panic_is_pixel_fg(sbuf8, spitch, x, y))
> +			if (drm_panic_is_pixel_fg(sbuf8, spitch, x / scale, y / scale))
>   				iosys_map_wr(dmap, y * dpitch + x * sizeof(u32), u32, fg32);
>   }
>   
>   static void drm_panic_blit_pixel(struct drm_scanout_buffer *sb, struct drm_rect *clip,
> -				 const u8 *sbuf8, unsigned int spitch, u32 fg_color)
> +				 const u8 *sbuf8, unsigned int spitch, unsigned int scale,
> +				 u32 fg_color)
>   {
>   	unsigned int y, x;
>   
>   	for (y = 0; y < drm_rect_height(clip); y++)
>   		for (x = 0; x < drm_rect_width(clip); x++)
> -			if (drm_panic_is_pixel_fg(sbuf8, spitch, x, y))
> +			if (drm_panic_is_pixel_fg(sbuf8, spitch, x / scale, y / scale))
>   				sb->set_pixel(sb, clip->x1 + x, clip->y1 + y, fg_color);
>   }
>   
> @@ -318,18 +319,22 @@ static void drm_panic_blit_pixel(struct drm_scanout_buffer *sb, struct drm_rect
>    * @clip: destination rectangle
>    * @sbuf8: source buffer, in monochrome format, 8 pixels per byte.
>    * @spitch: source pitch in bytes
> + * @scale: integer scale, source buffer is scale time smaller than destination
> + *         rectangle
>    * @fg_color: foreground color, in destination format
>    *
>    * This can be used to draw a font character, which is a monochrome image, to a
>    * framebuffer in other supported format.
>    */
>   static void drm_panic_blit(struct drm_scanout_buffer *sb, struct drm_rect *clip,
> -			   const u8 *sbuf8, unsigned int spitch, u32 fg_color)
> +			   const u8 *sbuf8, unsigned int spitch,
> +			   unsigned int scale, u32 fg_color)
> +
>   {
>   	struct iosys_map map;
>   
>   	if (sb->set_pixel)
> -		return drm_panic_blit_pixel(sb, clip, sbuf8, spitch, fg_color);
> +		return drm_panic_blit_pixel(sb, clip, sbuf8, spitch, scale, fg_color);
>   
>   	map = sb->map[0];
>   	iosys_map_incr(&map, clip->y1 * sb->pitch[0] + clip->x1 * sb->format->cpp[0]);
> @@ -337,15 +342,15 @@ static void drm_panic_blit(struct drm_scanout_buffer *sb, struct drm_rect *clip,
>   	switch (sb->format->cpp[0]) {
>   	case 2:
>   		drm_panic_blit16(&map, sb->pitch[0], sbuf8, spitch,
> -				 drm_rect_height(clip), drm_rect_width(clip), fg_color);
> +				 drm_rect_height(clip), drm_rect_width(clip), scale, fg_color);
>   	break;
>   	case 3:
>   		drm_panic_blit24(&map, sb->pitch[0], sbuf8, spitch,
> -				 drm_rect_height(clip), drm_rect_width(clip), fg_color);
> +				 drm_rect_height(clip), drm_rect_width(clip), scale, fg_color);
>   	break;
>   	case 4:
>   		drm_panic_blit32(&map, sb->pitch[0], sbuf8, spitch,
> -				 drm_rect_height(clip), drm_rect_width(clip), fg_color);
> +				 drm_rect_height(clip), drm_rect_width(clip), scale, fg_color);
>   	break;
>   	default:
>   		WARN_ONCE(1, "Can't blit with pixel width %d\n", sb->format->cpp[0]);
> @@ -485,7 +490,7 @@ static void draw_txt_rectangle(struct drm_scanout_buffer *sb,
>   		for (j = 0; j < line_len; j++) {
>   			src = get_char_bitmap(font, msg[i].txt[j], font_pitch);
>   			rec.x2 = rec.x1 + font->width;
> -			drm_panic_blit(sb, &rec, src, font_pitch, color);
> +			drm_panic_blit(sb, &rec, src, font_pitch, 1, color);
>   			rec.x1 += font->width;
>   		}
>   	}

-- 
--
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)