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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/avr32/mm/ioremap.c
Initial import
Diffstat (limited to 'arch/avr32/mm/ioremap.c')
-rw-r--r--arch/avr32/mm/ioremap.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/avr32/mm/ioremap.c b/arch/avr32/mm/ioremap.c
new file mode 100644
index 000000000..7def0d84c
--- /dev/null
+++ b/arch/avr32/mm/ioremap.c
@@ -0,0 +1,93 @@
+/*
+ * 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/mm.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#include <asm/pgtable.h>
+#include <asm/addrspace.h>
+
+/*
+ * 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)
+{
+ unsigned long 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_GLOBAL | _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 = (unsigned long )area->addr;
+ if (ioremap_page_range(addr, addr + size, phys_addr, prot)) {
+ vunmap((void *)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;
+ if (PXSEG(addr) == P2SEG)
+ 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);