1 files changed, 197 insertions, 0 deletions

diff --git a/arch/avr32/mm/ioremap.c b/arch/avr32/mm/ioremap.c
new file mode 100644
index 000000000000..536021877df6
--- /dev/null
+++ b/arch/avr32/mm/ioremap.c
@@ -0,0 +1,197 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/addrspace.h>
+
+static inline int remap_area_pte(pte_t *pte, unsigned long address,
+                                  unsigned long end, unsigned long phys_addr,
+                                  pgprot_t prot)
+{
+        unsigned long pfn;
+
+        pfn = phys_addr >> PAGE_SHIFT;
+        do {
+                WARN_ON(!pte_none(*pte));
+
+                set_pte(pte, pfn_pte(pfn, prot));
+                address += PAGE_SIZE;
+                pfn++;
+                pte++;
+        } while (address && (address < end));
+
+        return 0;
+}
+
+static inline int remap_area_pmd(pmd_t *pmd, unsigned long address,
+                                 unsigned long end, unsigned long phys_addr,
+                                 pgprot_t prot)
+{
+        unsigned long next;
+
+        phys_addr -= address;
+
+        do {
+                pte_t *pte = pte_alloc_kernel(pmd, address);
+                if (!pte)
+                        return -ENOMEM;
+
+                next = (address + PMD_SIZE) & PMD_MASK;
+                if (remap_area_pte(pte, address, next,
+                                   address + phys_addr, prot))
+                        return -ENOMEM;
+
+                address = next;
+                pmd++;
+        } while (address && (address < end));
+        return 0;
+}
+
+static int remap_area_pud(pud_t *pud, unsigned long address,
+                          unsigned long end, unsigned long phys_addr,
+                          pgprot_t prot)
+{
+        unsigned long next;
+
+        phys_addr -= address;
+
+        do {
+                pmd_t *pmd = pmd_alloc(&init_mm, pud, address);
+                if (!pmd)
+                        return -ENOMEM;
+                next = (address + PUD_SIZE) & PUD_MASK;
+                if (remap_area_pmd(pmd, address, next,
+                                   phys_addr + address, prot))
+                        return -ENOMEM;
+
+                address = next;
+                pud++;
+        } while (address && address < end);
+
+        return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+                            size_t size, pgprot_t prot)
+{
+        unsigned long end = address + size;
+        unsigned long next;
+        pgd_t *pgd;
+        int err = 0;
+
+        phys_addr -= address;
+
+        pgd = pgd_offset_k(address);
+        flush_cache_all();
+        BUG_ON(address >= end);
+
+        spin_lock(&init_mm.page_table_lock);
+        do {
+                pud_t *pud = pud_alloc(&init_mm, pgd, address);
+
+                err = -ENOMEM;
+                if (!pud)
+                        break;
+
+                next = (address + PGDIR_SIZE) & PGDIR_MASK;
+                if (next < address || next > end)
+                        next = end;
+                err = remap_area_pud(pud, address, next,
+                                     phys_addr + address, prot);
+                if (err)
+                        break;
+
+                address = next;
+                pgd++;
+        } while (address && (address < end));
+
+        spin_unlock(&init_mm.page_table_lock);
+        flush_tlb_all();
+        return err;
+}
+
+/*
+ * Re-map an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access physical
+ * memory directly.
+ */
+void __iomem *__ioremap(unsigned long phys_addr, size_t size,
+                        unsigned long flags)
+{
+        void *addr;
+        struct vm_struct *area;
+        unsigned long offset, last_addr;
+        pgprot_t prot;
+
+        /*
+         * Check if we can simply use the P4 segment. This area is
+         * uncacheable, so if caching/buffering is requested, we can't
+         * use it.
+         */
+        if ((phys_addr >= P4SEG) && (flags == 0))
+                return (void __iomem *)phys_addr;
+
+        /* Don't allow wraparound or zero size */
+        last_addr = phys_addr + size - 1;
+        if (!size || last_addr < phys_addr)
+                return NULL;
+
+        /*
+         * XXX: When mapping regular RAM, we'd better make damn sure
+         * it's never used for anything else.  But this is really the
+         * caller's responsibility...
+         */
+        if (PHYSADDR(P2SEGADDR(phys_addr)) == phys_addr)
+                return (void __iomem *)P2SEGADDR(phys_addr);
+
+        /* Mappings have to be page-aligned */
+        offset = phys_addr & ~PAGE_MASK;
+        phys_addr &= PAGE_MASK;
+        size = PAGE_ALIGN(last_addr + 1) - phys_addr;
+
+        prot = __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY
+                        | _PAGE_ACCESSED | _PAGE_TYPE_SMALL | flags);
+
+        /*
+         * Ok, go for it..
+         */
+        area = get_vm_area(size, VM_IOREMAP);
+        if (!area)
+                return NULL;
+        area->phys_addr = phys_addr;
+        addr = area->addr;
+        if (remap_area_pages((unsigned long)addr, phys_addr, size, prot)) {
+                vunmap(addr);
+                return NULL;
+        }
+
+        return (void __iomem *)(offset + (char *)addr);
+}
+EXPORT_SYMBOL(__ioremap);
+
+void __iounmap(void __iomem *addr)
+{
+        struct vm_struct *p;
+
+        if ((unsigned long)addr >= P4SEG)
+                return;
+
+        p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr));
+        if (unlikely(!p)) {
+                printk (KERN_ERR "iounmap: bad address %p\n", addr);
+                return;
+        }
+
+        kfree (p);
+}
+EXPORT_SYMBOL(__iounmap);