[deliverable/linux.git] / arch / arc / mm / ioremap.c

/*
 * 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>

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 (paddr >= ARC_UNCACHED_ADDR_SPACE)
		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)
{
	if (addr >= (void __force __iomem *)ARC_UNCACHED_ADDR_SPACE)
		return;

	vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
}
EXPORT_SYMBOL(iounmap);
Commit	Line	Data
1162b070 VG	1	/*
	2	* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/vmalloc.h>
	10	#include <linux/init.h>
	11	#include <linux/module.h>
	12	#include <linux/io.h>
	13	#include <linux/mm.h>
	14	#include <linux/slab.h>
1ec9db10	15	#include <linux/cache.h>
1162b070	16
f5db19e9	17	void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
1162b070	18	{
f5db19e9	19	phys_addr_t end;
1162b070 VG	20
	21	/* Don't allow wraparound or zero size */
	22	end = paddr + size - 1;
	23	if (!size \|\| (end < paddr))
	24	return NULL;
	25
f5db19e9 VG	26	/*
	27	* If the region is h/w uncached, MMU mapping can be elided as optim
	28	* The cast to u32 is fine as this region can only be inside 4GB
	29	*/
1162b070	30	if (paddr >= ARC_UNCACHED_ADDR_SPACE)
f5db19e9	31	return (void __iomem *)(u32)paddr;
1162b070	32
4368902b GBY	33	return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
	34	}
	35	EXPORT_SYMBOL(ioremap);
	36
	37	/*
	38	* ioremap with access flags
	39	* Cache semantics wise it is same as ioremap - "forced" uncached.
	40	* However unline vanilla ioremap which bypasses ARC MMU for addresses in
	41	* ARC hardware uncached region, this one still goes thru the MMU as caller
	42	* might need finer access control (R/W/X)
	43	*/
	44	void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
	45	unsigned long flags)
	46	{
f5db19e9	47	unsigned long vaddr;
4368902b	48	struct vm_struct *area;
f5db19e9	49	phys_addr_t off, end;
4368902b GBY	50	pgprot_t prot = __pgprot(flags);
	51
	52	/* Don't allow wraparound, zero size */
	53	end = paddr + size - 1;
	54	if ((!size) \|\| (end < paddr))
	55	return NULL;
	56
1162b070 VG	57	/* An early platform driver might end up here */
	58	if (!slab_is_available())
	59	return NULL;
	60
4368902b GBY	61	/* force uncached */
	62	prot = pgprot_noncached(prot);
	63
	64	/* Mappings have to be page-aligned */
1162b070 VG	65	off = paddr & ~PAGE_MASK;
	66	paddr &= PAGE_MASK;
	67	size = PAGE_ALIGN(end + 1) - paddr;
	68
	69	/*
	70	* Ok, go for it..
	71	*/
	72	area = get_vm_area(size, VM_IOREMAP);
	73	if (!area)
	74	return NULL;
1162b070	75	area->phys_addr = paddr;
f5db19e9 VG	76	vaddr = (unsigned long)area->addr;
f5db19e9 VG	77	if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {
4368902b	78	vunmap((void __force *)vaddr);
1162b070 VG	79	return NULL;
1162b070 VG	80	}
1162b070 VG	81	return (void __iomem )(off + (char __iomem )vaddr);
1162b070 VG	82	}
4368902b GBY	83	EXPORT_SYMBOL(ioremap_prot);
4368902b GBY	84
1162b070 VG	85
	86	void iounmap(const void __iomem *addr)
	87	{
	88	if (addr >= (void __force __iomem *)ARC_UNCACHED_ADDR_SPACE)
	89	return;
	90
	91	vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
	92	}
	93	EXPORT_SYMBOL(iounmap);