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-rw-r--r--arch/sh/mm/ioremap.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/sh/mm/ioremap.c b/arch/sh/mm/ioremap.c
new file mode 100644
index 000000000..213425811
--- /dev/null
+++ b/arch/sh/mm/ioremap.c
@@ -0,0 +1,192 @@
+/*
+ * arch/sh/mm/ioremap.c
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * (C) Copyright 2005 - 2010 Paul Mundt
+ *
+ * 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
+ *
+ * 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/slab.h>
+#include <linux/mm.h>
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <asm/io_trapped.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>
+#include "ioremap.h"
+
+/*
+ * On 32-bit SH, we traditionally have the whole physical address space mapped
+ * at all times (as MIPS does), so "ioremap()" and "iounmap()" do not need to do
+ * anything but place the address in the proper segment. This is true for P1
+ * and P2 addresses, as well as some P3 ones. However, most of the P3 addresses
+ * and newer cores using extended addressing need to map through page tables, so
+ * the ioremap() implementation becomes a bit more complicated.
+ */
+#ifdef CONFIG_29BIT
+static void __iomem *
+__ioremap_29bit(phys_addr_t offset, unsigned long size, pgprot_t prot)
+{
+ phys_addr_t last_addr = offset + size - 1;
+
+ /*
+ * For P1 and P2 space this is trivial, as everything is already
+ * mapped. Uncached access for P1 addresses are done through P2.
+ * In the P3 case or for addresses outside of the 29-bit space,
+ * mapping must be done by the PMB or by using page tables.
+ */
+ if (likely(PXSEG(offset) < P3SEG && PXSEG(last_addr) < P3SEG)) {
+ u64 flags = pgprot_val(prot);
+
+ /*
+ * Anything using the legacy PTEA space attributes needs
+ * to be kicked down to page table mappings.
+ */
+ if (unlikely(flags & _PAGE_PCC_MASK))
+ return NULL;
+ if (unlikely(flags & _PAGE_CACHABLE))
+ return (void __iomem *)P1SEGADDR(offset);
+
+ return (void __iomem *)P2SEGADDR(offset);
+ }
+
+ /* P4 above the store queues are always mapped. */
+ if (unlikely(offset >= P3_ADDR_MAX))
+ return (void __iomem *)P4SEGADDR(offset);
+
+ return NULL;
+}
+#else
+#define __ioremap_29bit(offset, size, prot) NULL
+#endif /* CONFIG_29BIT */
+
+/*
+ * 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 * __ref
+__ioremap_caller(phys_addr_t phys_addr, unsigned long size,
+ pgprot_t pgprot, void *caller)
+{
+ struct vm_struct *area;
+ unsigned long offset, last_addr, addr, orig_addr;
+ void __iomem *mapped;
+
+ mapped = __ioremap_trapped(phys_addr, size);
+ if (mapped)
+ return mapped;
+
+ mapped = __ioremap_29bit(phys_addr, size, pgprot);
+ if (mapped)
+ return mapped;
+
+ /* Don't allow wraparound or zero size */
+ last_addr = phys_addr + size - 1;
+ if (!size || last_addr < phys_addr)
+ return NULL;
+
+ /*
+ * If we can't yet use the regular approach, go the fixmap route.
+ */
+ if (!mem_init_done)
+ return ioremap_fixed(phys_addr, size, pgprot);
+
+ /*
+ * First try to remap through the PMB.
+ * PMB entries are all pre-faulted.
+ */
+ mapped = pmb_remap_caller(phys_addr, size, pgprot, caller);
+ if (mapped && !IS_ERR(mapped))
+ return mapped;
+
+ /*
+ * 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_caller(size, VM_IOREMAP, caller);
+ if (!area)
+ return NULL;
+ area->phys_addr = phys_addr;
+ orig_addr = addr = (unsigned long)area->addr;
+
+ 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_caller);
+
+/*
+ * Simple checks for non-translatable mappings.
+ */
+static inline int iomapping_nontranslatable(unsigned long offset)
+{
+#ifdef CONFIG_29BIT
+ /*
+ * In 29-bit mode this includes the fixed P1/P2 areas, as well as
+ * parts of P3.
+ */
+ if (PXSEG(offset) < P3SEG || offset >= P3_ADDR_MAX)
+ return 1;
+#endif
+
+ return 0;
+}
+
+void iounmap(void __iomem *addr)
+{
+ unsigned long vaddr = (unsigned long __force)addr;
+ struct vm_struct *p;
+
+ /*
+ * Nothing to do if there is no translatable mapping.
+ */
+ if (iomapping_nontranslatable(vaddr))
+ return;
+
+ /*
+ * There's no VMA if it's from an early fixed mapping.
+ */
+ if (iounmap_fixed(addr) == 0)
+ return;
+
+ /*
+ * If the PMB handled it, there's nothing else to do.
+ */
+ if (pmb_unmap(addr) == 0)
+ return;
+
+ p = remove_vm_area((void *)(vaddr & PAGE_MASK));
+ if (!p) {
+ printk(KERN_ERR "%s: bad address %p\n", __func__, addr);
+ return;
+ }
+
+ kfree(p);
+}
+EXPORT_SYMBOL(iounmap);