Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 */
5
6#include <linux/vmalloc.h>
7#include <linux/init.h>
8#include <linux/module.h>
9#include <linux/io.h>
10#include <linux/mm.h>
11#include <linux/cache.h>
12
13static inline bool arc_uncached_addr_space(phys_addr_t paddr)
14{
15 if (is_isa_arcompact()) {
16 if (paddr >= ARC_UNCACHED_ADDR_SPACE)
17 return true;
18 } else if (paddr >= perip_base && paddr <= perip_end) {
19 return true;
20 }
21
22 return false;
23}
24
25void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
26{
27 /*
28 * If the region is h/w uncached, MMU mapping can be elided as optim
29 * The cast to u32 is fine as this region can only be inside 4GB
30 */
31 if (arc_uncached_addr_space(paddr))
32 return (void __iomem *)(u32)paddr;
33
34 return ioremap_prot(paddr, size,
35 pgprot_noncached(PAGE_KERNEL));
36}
37EXPORT_SYMBOL(ioremap);
38
39/*
40 * ioremap with access flags
41 * Cache semantics wise it is same as ioremap - "forced" uncached.
42 * However unlike vanilla ioremap which bypasses ARC MMU for addresses in
43 * ARC hardware uncached region, this one still goes thru the MMU as caller
44 * might need finer access control (R/W/X)
45 */
46void __iomem *ioremap_prot(phys_addr_t paddr, size_t size,
47 pgprot_t prot)
48{
49 /* force uncached */
50 return generic_ioremap_prot(paddr, size, pgprot_noncached(prot));
51}
52EXPORT_SYMBOL(ioremap_prot);
53
54void iounmap(volatile void __iomem *addr)
55{
56 /* weird double cast to handle phys_addr_t > 32 bits */
57 if (arc_uncached_addr_space((phys_addr_t)(u32)addr))
58 return;
59
60 generic_iounmap(addr);
61}
62EXPORT_SYMBOL(iounmap);