From: "Luis R. Rodriguez" <[email protected]> This lets drivers take advantage of PAT when available. This 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() (de33c442e titled "x86 PAT: fix performance drop for glx, use UC minus for ioremap(), ioremap_nocache() and pci_mmap_page_range()")
Cc: Toshi Kani <[email protected]> Cc: Bjorn Helgaas <[email protected]> Cc: Suresh Siddha <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Airlie <[email protected]> Cc: Antonino Daplas <[email protected]> Cc: Jean-Christophe Plagniol-Villard <[email protected]> Cc: Tomi Valkeinen <[email protected]> Cc: Ville Syrjälä <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Luis R. Rodriguez <[email protected]> --- drivers/pci/pci.c | 14 ++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 15 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 0008c95..fdae37b 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 diff --git a/include/linux/pci.h b/include/linux/pci.h index c0dd4ab..1193975 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1657,6 +1657,7 @@ 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); -- 2.3.2.209.gd67f9d5.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/
