Re: [PATCH 2/2] simplefb: use write-combined remapping

From: David Herrmann
Date: Wed Oct 30 2013 - 03:49:12 EST


Hi Tomi

Ping?

Thanks
David

On Wed, Oct 2, 2013 at 4:58 PM, David Herrmann <dh.herrmann@xxxxxxxxx> wrote:
> 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@xxxxxxx>
> Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxx>
> Tested-by: Tom Gundersen <teg@xxxxxxx>
> Tested-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> Tested-by: Stephen Warren <swarren@xxxxxxxxxxxxx>
> ---
> drivers/video/simplefb.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/video/simplefb.c b/drivers/video/simplefb.c
> index 74b016c..64db54a 100644
> --- 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;
> --
> 1.8.4
>
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