Commit Graph

4 Commits

Author SHA1 Message Date
Luis R. Rodriguez
4edcd2ab12 drivers/video/fbdev/s3fb: Use arch_phys_wc_add() and pci_iomap_wc()
This driver uses the same area for MTRR as for the ioremap().

Convert the driver from using the x86-specific MTRR code to the
architecture-agnostic arch_phys_wc_add(). It will avoid MTRRs if
write-combining is available. In order to take advantage of that
also ensure the ioremapped 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 it is being 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 ifdeffery 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);

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: benh@kernel.crashing.org
Cc: bhelgaas@google.com
Cc: dan.j.williams@intel.com
Cc: konrad.wilk@oracle.com
Cc: linux-fbdev@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: mst@redhat.com
Cc: toshi.kani@hp.com
Cc: vinod.koul@intel.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1440443613-13696-8-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-25 09:59:45 +02:00
Lad, Prabhakar
c051af3152 video: fbdev: s3fb: suppress build warning
this patch fixes following build warning:
drivers/video/fbdev/s3fb.c: In function ‘s3_pci_probe’:
drivers/video/fbdev/s3fb.c:1185:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
  par->state.vgabase = (void __iomem *) vga_res.start;
                       ^
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-12-04 15:41:18 +02:00
Rickard Strandqvist
0c641bff31 video: fbdev: s3fb.c: Fix for possible null pointer dereference
There is otherwise a risk of a possible null pointer dereference.

Was largely found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-05-23 13:47:31 +03:00
Tomi Valkeinen
f7018c2135 video: move fbdev to drivers/video/fbdev
The drivers/video directory is a mess. It contains generic video related
files, directories for backlight, console, linux logo, lots of fbdev
device drivers, fbdev framework files.

Make some order into the chaos by creating drivers/video/fbdev
directory, and move all fbdev related files there.

No functionality is changed, although I guess it is possible that some
subtle Makefile build order related issue could be created by this
patch.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-04-17 08:10:19 +03:00