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:

  de33c442ed ("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>
This commit is contained in:
Luis R. Rodriguez 2015-08-24 12:13:23 -07:00 committed by Ingo Molnar
parent 8d58b66ed2
commit c43996f400
2 changed files with 15 additions and 0 deletions

View File

@ -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

View File

@ -1661,6 +1661,7 @@ static inline void pci_mmcfg_late_init(void) { }
int pci_ext_cfg_avail(void);
void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar);
void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar);
#ifdef CONFIG_PCI_IOV
int pci_iov_virtfn_bus(struct pci_dev *dev, int id);