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-rw-r--r--kernel/arch/m32r/mm/ioremap.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/kernel/arch/m32r/mm/ioremap.c b/kernel/arch/m32r/mm/ioremap.c
new file mode 100644
index 000000000..5152c4e6a
--- /dev/null
+++ b/kernel/arch/m32r/mm/ioremap.c
@@ -0,0 +1,111 @@
+/*
+ * linux/arch/m32r/mm/ioremap.c
+ *
+ * Copyright (c) 2001, 2002 Hiroyuki Kondo
+ *
+ * Taken from mips version.
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * (C) Copyright 2001 Ralf Baechle
+ */
+
+/*
+ * 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/module.h>
+#include <asm/addrspace.h>
+#include <asm/byteorder.h>
+
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <asm/pgalloc.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.
+ */
+
+#define IS_LOW512(addr) (!((unsigned long)(addr) & ~0x1fffffffUL))
+
+void __iomem *
+__ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+ void __iomem * addr;
+ struct vm_struct * area;
+ unsigned long offset, last_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;
+
+ /*
+ * Map objects in the low 512mb of address space using KSEG1, otherwise
+ * map using page tables.
+ */
+ if (IS_LOW512(phys_addr) && IS_LOW512(phys_addr + size - 1))
+ return (void *) KSEG1ADDR(phys_addr);
+
+ /*
+ * Don't allow anybody to remap normal RAM that we're using..
+ */
+ if (phys_addr < virt_to_phys(high_memory)) {
+ char *t_addr, *t_end;
+ struct page *page;
+
+ t_addr = __va(phys_addr);
+ t_end = t_addr + (size - 1);
+
+ for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
+ if(!PageReserved(page))
+ return NULL;
+ }
+
+ pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_READ
+ | _PAGE_WRITE | flags);
+
+ /*
+ * 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;
+ addr = (void __iomem *) area->addr;
+ if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
+ phys_addr, pgprot)) {
+ vunmap((void __force *) addr);
+ return NULL;
+ }
+
+ return (void __iomem *) (offset + (char __iomem *)addr);
+}
+
+#define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == KSEG1)
+
+void iounmap(volatile void __iomem *addr)
+{
+ if (!IS_KSEG1(addr))
+ vfree((void *) (PAGE_MASK & (unsigned long) addr));
+}
+