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-rw-r--r--kernel/arch/cris/mm/ioremap.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/kernel/arch/cris/mm/ioremap.c b/kernel/arch/cris/mm/ioremap.c
new file mode 100644
index 000000000..80fdb995a
--- /dev/null
+++ b/kernel/arch/cris/mm/ioremap.c
@@ -0,0 +1,89 @@
+/*
+ * arch/cris/mm/ioremap.c
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ * Needed for memory-mapped I/O devices mapped outside our normal DRAM
+ * window (that is, all memory-mapped I/O devices).
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * CRIS-port by Axis Communications AB
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <asm/pgalloc.h>
+#include <arch/memmap.h>
+
+/*
+ * Generic mapping function (not visible outside):
+ */
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access high addresses
+ * directly.
+ *
+ * NOTE! We need to allow non-page-aligned mappings too: we will obviously
+ * have to convert them into an offset in a page-aligned mapping, but the
+ * caller shouldn't need to know that small detail.
+ */
+void __iomem * __ioremap_prot(unsigned long phys_addr, unsigned long size, pgprot_t prot)
+{
+ void __iomem * addr;
+ struct vm_struct * area;
+ unsigned long offset, last_addr;
+
+ /* Don't allow wraparound or zero size */
+ last_addr = phys_addr + size - 1;
+ if (!size || last_addr < phys_addr)
+ return NULL;
+
+ /*
+ * Mappings have to be page-aligned
+ */
+ offset = phys_addr & ~PAGE_MASK;
+ phys_addr &= PAGE_MASK;
+ size = PAGE_ALIGN(last_addr+1) - phys_addr;
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+ addr = (void __iomem *)area->addr;
+ if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
+ phys_addr, prot)) {
+ vfree((void __force *)addr);
+ return NULL;
+ }
+ return (void __iomem *) (offset + (char __iomem *)addr);
+}
+
+void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+ return __ioremap_prot(phys_addr, size,
+ __pgprot(_PAGE_PRESENT | __READABLE |
+ __WRITEABLE | _PAGE_GLOBAL |
+ _PAGE_KERNEL | flags));
+}
+
+/**
+ * ioremap_nocache - map bus memory into CPU space
+ * @offset: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * Must be freed with iounmap.
+ */
+
+void __iomem *ioremap_nocache(unsigned long phys_addr, unsigned long size)
+{
+ return __ioremap(phys_addr | MEM_NON_CACHEABLE, size, 0);
+}
+EXPORT_SYMBOL(ioremap_nocache);
+
+void iounmap(volatile void __iomem *addr)
+{
+ if (addr > high_memory)
+ return vfree((void *) (PAGE_MASK & (unsigned long) addr));
+}