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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /lib/pci_iomap.c
Initial import
Diffstat (limited to 'lib/pci_iomap.c')
-rw-r--r--lib/pci_iomap.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
new file mode 100644
index 000000000..bcce5f149
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+++ b/lib/pci_iomap.c
@@ -0,0 +1,73 @@
+/*
+ * Implement the default iomap interfaces
+ *
+ * (C) Copyright 2004 Linus Torvalds
+ */
+#include <linux/pci.h>
+#include <linux/io.h>
+
+#include <linux/export.h>
+
+#ifdef CONFIG_PCI
+/**
+ * pci_iomap_range - create a virtual mapping cookie for a PCI BAR
+ * @dev: PCI device that owns the BAR
+ * @bar: BAR number
+ * @offset: map memory at the given offset in BAR
+ * @maxlen: max length of the memory to map
+ *
+ * Using this function you will get a __iomem address to your device BAR.
+ * You can access it using ioread*() and iowrite*(). These functions hide
+ * the details if this is a MMIO or PIO address space and will just do what
+ * you expect from them in the correct way.
+ *
+ * @maxlen specifies the maximum length to map. If you want to get access to
+ * the complete BAR from offset to the end, pass %0 here.
+ * */
+void __iomem *pci_iomap_range(struct pci_dev *dev,
+ int bar,
+ unsigned long offset,
+ unsigned long maxlen)
+{
+ resource_size_t start = pci_resource_start(dev, bar);
+ resource_size_t len = pci_resource_len(dev, bar);
+ unsigned long flags = pci_resource_flags(dev, bar);
+
+ if (len <= offset || !start)
+ return NULL;
+ len -= offset;
+ start += offset;
+ if (maxlen && len > maxlen)
+ len = maxlen;
+ if (flags & IORESOURCE_IO)
+ return __pci_ioport_map(dev, start, len);
+ if (flags & IORESOURCE_MEM) {
+ if (flags & IORESOURCE_CACHEABLE)
+ return ioremap(start, len);
+ return ioremap_nocache(start, len);
+ }
+ /* What? */
+ return NULL;
+}
+EXPORT_SYMBOL(pci_iomap_range);
+
+/**
+ * pci_iomap - create a virtual mapping cookie for a PCI BAR
+ * @dev: PCI device that owns the BAR
+ * @bar: BAR number
+ * @maxlen: length of the memory to map
+ *
+ * Using this function you will get a __iomem address to your device BAR.
+ * You can access it using ioread*() and iowrite*(). These functions hide
+ * the details if this is a MMIO or PIO address space and will just do what
+ * you expect from them in the correct way.
+ *
+ * @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_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
+{
+ return pci_iomap_range(dev, bar, 0, maxlen);
+}
+EXPORT_SYMBOL(pci_iomap);
+#endif /* CONFIG_PCI */