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SubjectRe: [PATCH] Clarify pci_iomap() usage for MMIO-only devices
Benjamin Herrenschmidt wrote:
> On Tue, 2007-09-18 at 16:21 -0400, Jeff Garzik wrote:
>> A new pci_mmio_map() helper, to be used with 100% MMIO hardware, might
>> help eliminate confusion.
>
> Maybe not the best name in theory but at least would show that it
> relates to existing ioremap would be pci_ioremap()


Easy enough... 'pcimap' branch of
git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6.git

Jeff


commit 6e09c71822f76c618353682bf295fc7588284521
Author: Jeff Garzik <jeff@garzik.org>
Date: Tue Sep 18 19:06:08 2007 -0400

Add pci_ioremap() to generic iomap lib.

(arches that don't wish to use lib/iomap.c's version may fill in their own)

Signed-off-by: Jeff Garzik <jeff@garzik.org>

include/asm-generic/iomap.h | 1 +
lib/iomap.c | 34 ++++++++++++++++++++++++++++++++++
2 files changed, 35 insertions(+)

6e09c71822f76c618353682bf295fc7588284521
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index cde592f..611e6cf 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -63,6 +63,7 @@ extern void ioport_unmap(void __iomem *);
/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
struct pci_dev;
extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max);
+extern void __iomem *pci_ioremap(struct pci_dev *dev, int bar, unsigned long max);
extern void pci_iounmap(struct pci_dev *dev, void __iomem *);

#endif
diff --git a/lib/iomap.c b/lib/iomap.c
index 864f2ec..0338da0 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -275,9 +275,43 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
return NULL;
}

+/**
+ * pci_ioremap - create a virtual mapping cookie for a memory-based PCI BAR
+ * @dev: PCI device that owns the BAR
+ * @bar: BAR number
+ * @maxlen: length of MMIO memory to map
+ *
+ * Using this function you will get a __iomem address to your device BAR.
+ * You can access it using read*() and write*().
+ *
+ * @maxlen specifies the maximum length to map. If you want to get access to
+ * the complete BAR without checking for its length first, pass %0 here.
+ * */
+void __iomem *pci_ioremap(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+ unsigned long start = pci_resource_start(dev, bar);
+ unsigned long len = pci_resource_len(dev, bar);
+ unsigned long flags = pci_resource_flags(dev, bar);
+
+ if (!len || !start)
+ return NULL;
+ if (maxlen && len > maxlen)
+ len = maxlen;
+ if (flags & IORESOURCE_IO)
+ return NULL;
+ if (flags & IORESOURCE_MEM) {
+ if (flags & IORESOURCE_CACHEABLE)
+ return ioremap(start, len);
+ return ioremap_nocache(start, len);
+ }
+ /* What? */
+ return NULL;
+}
+
void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
{
IO_COND(addr, /* nothing */, iounmap(addr));
}
EXPORT_SYMBOL(pci_iomap);
+EXPORT_SYMBOL(pci_ioremap);
EXPORT_SYMBOL(pci_iounmap);
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