Re: [PATCH v5 1/4] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64

[Helge Deller]

On 9/21/23 13:04, Baoquan He wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> ioremap_uc() is only meaningful on old x86-32 systems with the PAT
> extension, and on ia64 with its slightly unconventional ioremap()
> behavior, everywhere else this is the same as ioremap() anyway.
>
> Change the only driver that still references ioremap_uc() to only do so
> on x86-32/ia64 in order to allow removing that interface at some
> point in the future for the other architectures.
>
> On some architectures, ioremap_uc() just returns NULL, changing
> the driver to call ioremap() means that they now have a chance
> of working correctly.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
> Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> Cc: Helge Deller <deller@xxxxxx>
> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
> Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> Cc: linux-fbdev@xxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx

applied to fbdev git tree.

Thanks!
Helge


> ---
>   drivers/video/fbdev/aty/atyfb_base.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/drivers/video/fbdev/aty/atyfb_base.c b/drivers/video/fbdev/aty/atyfb_base.c
> index 5c87817a4f4c..3dcf83f5e7b4 100644
> --- a/drivers/video/fbdev/aty/atyfb_base.c
> +++ b/drivers/video/fbdev/aty/atyfb_base.c
> @@ -3440,11 +3440,15 @@ static int atyfb_setup_generic(struct pci_dev *pdev, struct fb_info *info,
>   	}
>
>   	info->fix.mmio_start = raddr;
> +#if defined(__i386__) || defined(__ia64__)
>   	/*
>   	 * By using strong UC we force the MTRR to never have an
>   	 * effect on the MMIO region on both non-PAT and PAT systems.
>   	 */
>   	par->ati_regbase = ioremap_uc(info->fix.mmio_start, 0x1000);
> +#else
> +	par->ati_regbase = ioremap(info->fix.mmio_start, 0x1000);
> +#endif
>   	if (par->ati_regbase == NULL)
>   		return -ENOMEM;