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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* 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/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/cache.h>
static inline bool arc_uncached_addr_space(phys_addr_t paddr)
{
if (is_isa_arcompact()) {
if (paddr >= ARC_UNCACHED_ADDR_SPACE)
return true;
} else if (paddr >= perip_base && paddr <= 0xFFFFFFFF) {
return true;
}
return false;
}
void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
{
phys_addr_t end;
/* Don't allow wraparound or zero size */
end = paddr + size - 1;
if (!size || (end < paddr))
return NULL;
/*
* If the region is h/w uncached, MMU mapping can be elided as optim
* The cast to u32 is fine as this region can only be inside 4GB
*/
if (arc_uncached_addr_space(paddr))
return (void __iomem *)(u32)paddr;
return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
}
EXPORT_SYMBOL(ioremap);
/*
* ioremap with access flags
* Cache semantics wise it is same as ioremap - "forced" uncached.
* However unline vanilla ioremap which bypasses ARC MMU for addresses in
* ARC hardware uncached region, this one still goes thru the MMU as caller
* might need finer access control (R/W/X)
*/
void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
unsigned long flags)
{
unsigned long vaddr;
struct vm_struct *area;
phys_addr_t off, end;
pgprot_t prot = __pgprot(flags);
/* Don't allow wraparound, zero size */
end = paddr + size - 1;
if ((!size) || (end < paddr))
return NULL;
/* An early platform driver might end up here */
if (!slab_is_available())
return NULL;
/* force uncached */
prot = pgprot_noncached(prot);
/* Mappings have to be page-aligned */
off = paddr & ~PAGE_MASK;
paddr &= PAGE_MASK;
size = PAGE_ALIGN(end + 1) - paddr;
/*
* Ok, go for it..
*/
area = get_vm_area(size, VM_IOREMAP);
if (!area)
return NULL;
area->phys_addr = paddr;
vaddr = (unsigned long)area->addr;
if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {
vunmap((void __force *)vaddr);
return NULL;
}
return (void __iomem *)(off + (char __iomem *)vaddr);
}
EXPORT_SYMBOL(ioremap_prot);
void iounmap(const void __iomem *addr)
{
/* weird double cast to handle phys_addr_t > 32 bits */
if (arc_uncached_addr_space((phys_addr_t)(u32)addr))
return;
vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
}
EXPORT_SYMBOL(iounmap);
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