Re: [PATCH v3] staging: sm750fb: use arch_phys_wc_add() and ioremap_wc()

[Luis R. Rodriguez]

On Tue, Apr 21, 2015 at 1:13 PM, Luis R. Rodriguez
<mcgrof@xxxxxxxxxxxxxxxx> wrote:
> From: "Luis R. Rodriguez" <mcgrof@xxxxxxxx>
>
> The same area used for ioremap() is used for the MTRR area.
> Convert the driver from using the x86 specific MTRR code to
> the architecture agnostic arch_phys_wc_add(). arch_phys_wc_add()
> will avoid MTRR if write-combining is available, in order to
> take advantage of that also ensure the ioremap'd area is requested
> as write-combining.
>
> There are a few motivations for this:
>
> a) Take advantage of PAT when available
>
> b) Help bury MTRR code away, MTRR is architecture specific and on
>    x86 its replaced by PAT
>
> c) Help with the goal of eventually using _PAGE_CACHE_UC over
>    _PAGE_CACHE_UC_MINUS on x86 on ioremap_nocache() (see commit
>    de33c442e titled "x86 PAT: fix performance drop for glx,
>    use UC minus for ioremap(), ioremap_nocache() and
>    pci_mmap_page_range()")
>
> The conversion done is expressed by the following Coccinelle
> SmPL patch, it additionally required manual intervention to
> address all the #ifdery and removal of redundant things which
> arch_phys_wc_add() already addresses such as verbose message
> about when MTRR fails and doing nothing when we didn't get
> an MTRR.
>
> @ mtrr_found @
> expression index, base, size;
> @@
>
> -index = mtrr_add(base, size, MTRR_TYPE_WRCOMB, 1);
> +index = arch_phys_wc_add(base, size);
>
> @ mtrr_rm depends on mtrr_found @
> expression mtrr_found.index, mtrr_found.base, mtrr_found.size;
> @@
>
> -mtrr_del(index, base, size);
> +arch_phys_wc_del(index);
>
> @ mtrr_rm_zero_arg depends on mtrr_found @
> expression mtrr_found.index;
> @@
>
> -mtrr_del(index, 0, 0);
> +arch_phys_wc_del(index);
>
> @ mtrr_rm_fb_info depends on mtrr_found @
> struct fb_info *info;
> expression mtrr_found.index;
> @@
>
> -mtrr_del(index, info->fix.smem_start, info->fix.smem_len);
> +arch_phys_wc_del(index);
>
> @ ioremap_replace_nocache depends on mtrr_found @
> struct fb_info *info;
> expression base, size;
> @@
>
> -info->screen_base = ioremap_nocache(base, size);
> +info->screen_base = ioremap_wc(base, size);
>
> @ ioremap_replace_default depends on mtrr_found @
> struct fb_info *info;
> expression base, size;
> @@
>
> -info->screen_base = ioremap(base, size);
> +info->screen_base = ioremap_wc(base, size);
>
> Generated-by: Coccinelle SmPL
> Cc: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx>
> Cc: Teddy Wang <teddy.wang@xxxxxxxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Suresh Siddha <sbsiddha@xxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Juergen Gross <jgross@xxxxxxxx>
> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> Cc: Dave Airlie <airlied@xxxxxxxxxx>
> Cc: Antonino Daplas <adaplas@xxxxxxxxx>
> Cc: Jean-Christophe Plagniol-Villard <plagnioj@xxxxxxxxxxxx>
> Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
> Cc: devel@xxxxxxxxxxxxxxxxxxxx
> Cc: linux-fbdev@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxx>

Hey folks, just a follow up. Can this be considered to be merged?

 Luis
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/