diff options
| author | Luis R. Rodriguez <mcgrof@suse.com> | 2015-08-24 12:13:23 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-08-25 09:59:43 +0200 |
| commit | c43996f4001de629af4a4d6713782e883677e5b9 (patch) | |
| tree | 55f37c67d90ace6fb51277b95df9aeb43068b9b4 /drivers/pci/pci.c | |
| parent | 8d58b66ed2b000f27658c88a4ed70e8042e86a58 (diff) | |
PCI: Add pci_ioremap_wc_bar()
This lets drivers take advantage of PAT when available. It
should help with the transition of converting video drivers over
to ioremap_wc() to help with the goal of eventually using
_PAGE_CACHE_UC over _PAGE_CACHE_UC_MINUS on x86 on
ioremap_nocache(), see:
de33c442ed2a ("x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()")
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: <syrjala@sci.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Ville Syrjälä <syrjala@sci.fi>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: airlied@linux.ie
Cc: benh@kernel.crashing.org
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: vinod.koul@intel.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1440443613-13696-2-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 0008c950452c..fdae37b473f8 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -138,6 +138,20 @@ void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar) return ioremap_nocache(res->start, resource_size(res)); } EXPORT_SYMBOL_GPL(pci_ioremap_bar); + +void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar) +{ + /* + * Make sure the BAR is actually a memory resource, not an IO resource + */ + if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) { + WARN_ON(1); + return NULL; + } + return ioremap_wc(pci_resource_start(pdev, bar), + pci_resource_len(pdev, bar)); +} +EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar); #endif #define PCI_FIND_CAP_TTL 48 |