sh: Split out ioremap in to _32 and _64 variants.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

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 00000000000..0c7b7e33abd
--- /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);