Commit 3c004b4f authored May 26, 2011 by Andy Lutomirski Committed by Paul Mundt Jun 02, 2011

efifb: Enable write-combining



Running fbcon on an uncached framebuffer is remarkably slow.  So try
to enable write combining in efifb.

Without this patch, it takes 5.8 seconds from efifb probe to i915
probe (default options; no plymouth or quiet mode).  With this patch,
it only takes 1.7 seconds.  That means we wasted over 4 seconds just
writing to UC memory.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

parent 0057f180

drivers/video/efifb.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -413,7 +413,7 @@ static int __devinit efifb_probe(struct platform_device *dev)
		info->apertures->ranges[0].base = efifb_fix.smem_start;
		info->apertures->ranges[0].size = size_remap;

		info->screen_base = ioremap(efifb_fix.smem_start, efifb_fix.smem_len);
		info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
		if (!info->screen_base) {
		printk(KERN_ERR "efifb: abort, cannot ioremap video memory "
		"0x%x @ 0x%lx\n",

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