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/*
* arch/cris/mm/ioremap.c
*
* Re-map IO memory to kernel address space so that we can access it.
* Needed for memory-mapped I/O devices mapped outside our normal DRAM
* window (that is, all memory-mapped I/O devices).
*
* (C) Copyright 1995 1996 Linus Torvalds
* CRIS-port by Axis Communications AB
*/
#include <linux/vmalloc.h>
#include <linux/io.h>
#include <asm/pgalloc.h>
#include <arch/memmap.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.
*/
void __iomem * __ioremap_prot(unsigned long phys_addr, unsigned long size, pgprot_t prot)
{
void __iomem * addr;
struct vm_struct * area;
unsigned long offset, last_addr;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
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;
addr = (void __iomem *)area->addr;
if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
phys_addr, prot)) {
vfree((void __force *)addr);
return NULL;
}
return (void __iomem *) (offset + (char __iomem *)addr);
}
void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
{
return __ioremap_prot(phys_addr, size,
__pgprot(_PAGE_PRESENT | __READABLE |
__WRITEABLE | _PAGE_GLOBAL |
_PAGE_KERNEL | flags));
}
/**
* ioremap_nocache - map bus memory into CPU space
* @offset: bus address of the memory
* @size: size of the resource to map
*
* Must be freed with iounmap.
*/
void __iomem *ioremap_nocache(unsigned long phys_addr, unsigned long size)
{
return __ioremap(phys_addr | MEM_NON_CACHEABLE, size, 0);
}
EXPORT_SYMBOL(ioremap_nocache);
void iounmap(volatile void __iomem *addr)
{
if (addr > high_memory)
return vfree((void *) (PAGE_MASK & (unsigned long) addr));
}
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