drivers/video/fbdev/s3fb: Use arch_phys_wc_add() and pci_iomap_wc()

2015-08-25T07:59:45Z

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 Signed-off-by: Borislav Petkov Acked-by: Tomi Valkeinen Cc: Andrew Morton Cc: Andy Lutomirski Cc: Antonino Daplas Cc: Arnd Bergmann Cc: Daniel Vetter Cc: Dave Airlie Cc: Geert Uytterhoeven Cc: H. Peter Anvin Cc: Jean-Christophe Plagniol-Villard Cc: Jingoo Han Cc: Juergen Gross Cc: Lad, Prabhakar Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rickard Strandqvist Cc: Suresh Siddha Cc: Thomas Gleixner 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

video: fbdev: s3fb: suppress build warning

2014-12-04T13:41:18Z

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 Signed-off-by: Tomi Valkeinen

video: fbdev: s3fb.c: Fix for possible null pointer dereference

2014-05-23T10:47:31Z

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 Signed-off-by: Tomi Valkeinen

video: move fbdev to drivers/video/fbdev

2014-04-17T05:10:19Z

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 Acked-by: Laurent Pinchart Acked-by: Geert Uytterhoeven Acked-by: Rob Clark Acked-by: Jingoo Han Acked-by: Daniel Vetter

user/sven/linux.git/drivers/video/fbdev/s3fb.c, branch v4.9.99

drivers/video/fbdev/s3fb: Use arch_phys_wc_add() and pci_iomap_wc()

video: fbdev: s3fb: suppress build warning

video: fbdev: s3fb.c: Fix for possible null pointer dereference

video: move fbdev to drivers/video/fbdev