simplefb: use write-combined remapping

Framebuffers shouldn't be cached and it is usually very uncommon to read
them. Therefore, use ioremap_wc() to get significant speed improvements on
systems which provide it. On all other systems it's aliased to
ioremap_nocache() which is also fine.

Reported-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Tested-by: Tom Gundersen <teg@jklm.no>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

diff --git a/drivers/video/simplefb.c b/drivers/video/simplefb.c
index 129ab19..210f3a0 100644 (file)
--- a/drivers/video/simplefb.c
+++ b/drivers/video/simplefb.c
@@ -219,8 +219,8 @@ static int simplefb_probe(struct platform_device *pdev)
 
        info->fbops = &simplefb_ops;
        info->flags = FBINFO_DEFAULT | FBINFO_MISC_FIRMWARE;
-       info->screen_base = ioremap(info->fix.smem_start,
-                                   info->fix.smem_len);
+       info->screen_base = ioremap_wc(info->fix.smem_start,
+                                      info->fix.smem_len);
        if (!info->screen_base) {
                framebuffer_release(info);
                return -ENODEV;