On Sun, Mar 13, 2022 at 08:29:52PM +0100, Thomas Zimmermann wrote:
Commit 0d03011894d2 ("fbdev: Improve performance of cfb_imageblit()") broke cfb_imageblit() for image widths that are not aligned to 8-bit boundaries. Fix this by handling the trailing pixels on each line separately. The performance improvements in the original commit do not regress by this change.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: 0d03011894d2 ("fbdev: Improve performance of cfb_imageblit()") Reported-by: Marek Szyprowski m.szyprowski@samsung.com Cc: Thomas Zimmermann tzimmermann@suse.de Cc: Javier Martinez Canillas javierm@redhat.com Cc: Sam Ravnborg sam@ravnborg.org Tested-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Daniel Vetter daniel.vetter@ffwll.ch Reviewed-by: Javier Martinez Canillas javierm@redhat.com
Tested-by: Guenter Roeck linux@roeck-us.net
drivers/video/fbdev/core/cfbimgblt.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-)
diff --git a/drivers/video/fbdev/core/cfbimgblt.c b/drivers/video/fbdev/core/cfbimgblt.c index 7361cfabdd85..9ebda4e0dc7a 100644 --- a/drivers/video/fbdev/core/cfbimgblt.c +++ b/drivers/video/fbdev/core/cfbimgblt.c @@ -218,7 +218,7 @@ static inline void fast_imageblit(const struct fb_image *image, struct fb_info * { u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel; u32 ppw = 32/bpp, spitch = (image->width + 7)/8;
- u32 bit_mask, eorx;
- u32 bit_mask, eorx, shift; const char *s = image->data, *src; u32 __iomem *dst; const u32 *tab = NULL;
@@ -259,17 +259,23 @@ static inline void fast_imageblit(const struct fb_image *image, struct fb_info *
for (i = image->height; i--; ) { dst = (u32 __iomem *)dst1;
shift = 8;src = s;
/** Manually unroll the per-line copying loop for better* performance. This works until we processed the last* completely filled source byte (inclusive).*/switch (ppw) { case 4: /* 8 bpp */
for (j = k; j; j -= 2, ++src) {
for (j = k; j >= 2; j -= 2, ++src) { FB_WRITEL(colortab[(*src >> 4) & bit_mask], dst++); FB_WRITEL(colortab[(*src >> 0) & bit_mask], dst++); } break;
for (j = k; j; j -= 4, ++src) {
for (j = k; j >= 4; j -= 4, ++src) { FB_WRITEL(colortab[(*src >> 6) & bit_mask], dst++); FB_WRITEL(colortab[(*src >> 4) & bit_mask], dst++); FB_WRITEL(colortab[(*src >> 2) & bit_mask], dst++);@@ -277,7 +283,7 @@ static inline void fast_imageblit(const struct fb_image *image, struct fb_info * } break; case 1: /* 32 bpp */
for (j = k; j; j -= 8, ++src) {
for (j = k; j >= 8; j -= 8, ++src) { FB_WRITEL(colortab[(*src >> 7) & bit_mask], dst++); FB_WRITEL(colortab[(*src >> 6) & bit_mask], dst++); FB_WRITEL(colortab[(*src >> 5) & bit_mask], dst++);@@ -290,6 +296,20 @@ static inline void fast_imageblit(const struct fb_image *image, struct fb_info * break; }
/** For image widths that are not a multiple of 8, there* are trailing pixels left on the current line. Print* them as well.*/for (; j--; ) {shift -= ppw;FB_WRITEL(colortab[(*src >> shift) & bit_mask], dst++);if (!shift) {shift = 8;++src;}}- dst1 += p->fix.line_length; s += spitch; }