6d463de46
Linus Walleij
2012-09-06
Subject
fbsplash: support non-RGB565 pixels in 16-bit mode
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miscutils/fbsplash.c+22 -5
| @@ -50,6 +50,10 @@ struct globals { | |
| struct fb_var_screeninfo scr_var; | |
| struct fb_fix_screeninfo scr_fix; | |
| unsigned bytes_per_pixel; | |
| + | // cached (8 - scr_var.COLOR.length): |
| + | unsigned red_shift; |
| + | unsigned green_shift; |
| + | unsigned blue_shift; |
| }; | |
| #define G (*ptr_to_globals) | |
| #define INIT_G() do { \ | |
| @@ -139,6 +143,9 @@ static void fb_open(const char *strfb_device) | |
| break; | |
| } | |
| + | G.red_shift = 8 - G.scr_var.red.length; |
| + | G.green_shift = 8 - G.scr_var.green.length; |
| + | G.blue_shift = 8 - G.scr_var.blue.length; |
| G.bytes_per_pixel = (G.scr_var.bits_per_pixel + 7) >> 3; | |
| // map the device in memory | |
| @@ -155,10 +162,13 @@ static void fb_open(const char *strfb_device) | |
| /** | |
| - | * Return pixel value of the passed RGB color |
| + | * Return pixel value of the passed RGB color. |
| + | * This is performance critical fn. |
| */ | |
| static unsigned fb_pixel_value(unsigned r, unsigned g, unsigned b) | |
| { | |
| + | /* We assume that the r,g,b values are <= 255 */ |
| + | |
| if (G.bytes_per_pixel == 1) { | |
| r = r & 0xe0; // 3-bit red | |
| g = (g >> 3) & 0x1c; // 3-bit green | |
| @@ -166,10 +176,17 @@ static unsigned fb_pixel_value(unsigned r, unsigned g, unsigned b) | |
| return r + g + b; | |
| } | |
| if (G.bytes_per_pixel == 2) { | |
| - | r = (r & 0xf8) << 8; // 5-bit red |
| - | g = (g & 0xfc) << 3; // 6-bit green |
| - | b = b >> 3; // 5-bit blue |
| - | return r + g + b; |
| + | // ARM PL110 on Integrator/CP has RGBA5551 bit arrangement. |
| + | // We want to support bit locations like that. |
| + | // |
| + | // First shift out unused bits |
| + | r = r >> G.red_shift; |
| + | g = g >> G.green_shift; |
| + | b = b >> G.blue_shift; |
| + | // Then shift the remaining bits to their offset |
| + | return (r << G.scr_var.red.offset) + |
| + | (g << G.scr_var.green.offset) + |
| + | (b << G.scr_var.blue.offset); |
| } | |
| // RGB 888 | |
| return b + (g << 8) + (r << 16); | |