1 files changed, 150 insertions, 0 deletions

diff --git a/arch/sh/mm/ioremap_32.c b/arch/sh/mm/ioremap_32.c
new file mode 100644
index 000000000000..0c7b7e33abdc
--- /dev/null
+++ b/arch/sh/mm/ioremap_32.c
@@ -0,0 +1,150 @@
+/*
+ * arch/sh/mm/ioremap.c
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ * This is needed for high PCI addresses that aren't mapped in the
+ * 640k-1MB IO memory area on PC's
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * (C) Copyright 2005, 2006 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ */
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/addrspace.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu.h>
+
+/*
+ * 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(unsigned long phys_addr, unsigned long size,
+                        unsigned long flags)
+{
+        struct vm_struct * area;
+        unsigned long offset, last_addr, addr, orig_addr;
+        pgprot_t pgprot;
+
+        /* Don't allow wraparound or zero size */
+        last_addr = phys_addr + size - 1;
+        if (!size || last_addr < phys_addr)
+                return NULL;
+
+        /*
+         * If we're on an SH7751 or SH7780 PCI controller, PCI memory is
+         * mapped at the end of the address space (typically 0xfd000000)
+         * in a non-translatable area, so mapping through page tables for
+         * this area is not only pointless, but also fundamentally
+         * broken. Just return the physical address instead.
+         *
+         * For boards that map a small PCI memory aperture somewhere in
+         * P1/P2 space, ioremap() will already do the right thing,
+         * and we'll never get this far.
+         */
+        if (is_pci_memaddr(phys_addr) && is_pci_memaddr(last_addr))
+                return (void __iomem *)phys_addr;
+
+        /*
+         * Don't allow anybody to remap normal RAM that we're using..
+         */
+        if (phys_addr < virt_to_phys(high_memory))
+                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;
+        area->phys_addr = phys_addr;
+        orig_addr = addr = (unsigned long)area->addr;
+
+#ifdef CONFIG_32BIT
+        /*
+         * First try to remap through the PMB once a valid VMA has been
+         * established. Smaller allocations (or the rest of the size
+         * remaining after a PMB mapping due to the size not being
+         * perfectly aligned on a PMB size boundary) are then mapped
+         * through the UTLB using conventional page tables.
+         *
+         * PMB entries are all pre-faulted.
+         */
+        if (unlikely(size >= 0x1000000)) {
+                unsigned long mapped = pmb_remap(addr, phys_addr, size, flags);
+
+                if (likely(mapped)) {
+                        addr            += mapped;
+                        phys_addr       += mapped;
+                        size            -= mapped;
+                }
+        }
+#endif
+
+        pgprot = __pgprot(pgprot_val(PAGE_KERNEL_NOCACHE) | flags);
+        if (likely(size))
+                if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) {
+                        vunmap((void *)orig_addr);
+                        return NULL;
+                }
+
+        return (void __iomem *)(offset + (char *)orig_addr);
+}
+EXPORT_SYMBOL(__ioremap);
+
+void __iounmap(void __iomem *addr)
+{
+        unsigned long vaddr = (unsigned long __force)addr;
+        struct vm_struct *p;
+
+        if (PXSEG(vaddr) < P3SEG || is_pci_memaddr(vaddr))
+                return;
+
+#ifdef CONFIG_32BIT
+        /*
+         * Purge any PMB entries that may have been established for this
+         * mapping, then proceed with conventional VMA teardown.
+         *
+         * XXX: Note that due to the way that remove_vm_area() does
+         * matching of the resultant VMA, we aren't able to fast-forward
+         * the address past the PMB space until the end of the VMA where
+         * the page tables reside. As such, unmap_vm_area() will be
+         * forced to linearly scan over the area until it finds the page
+         * tables where PTEs that need to be unmapped actually reside,
+         * which is far from optimal. Perhaps we need to use a separate
+         * VMA for the PMB mappings?
+         *                                      -- PFM.
+         */
+        pmb_unmap(vaddr);
+#endif
+
+        p = remove_vm_area((void *)(vaddr & PAGE_MASK));
+        if (!p) {
+                printk(KERN_ERR "%s: bad address %p\n", __FUNCTION__, addr);
+                return;
+        }
+
+        kfree(p);
+}
+EXPORT_SYMBOL(__iounmap);