xref: /openbmc/linux/arch/xtensa/mm/ioremap.c (revision 23c2b932)
1 /*
2  * ioremap implementation.
3  *
4  * Copyright (C) 2015 Cadence Design Systems Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/io.h>
12 #include <linux/vmalloc.h>
13 #include <asm/cacheflush.h>
14 #include <asm/io.h>
15 #include <asm/pgtable.h>
16 
17 static void __iomem *xtensa_ioremap(unsigned long paddr, unsigned long size,
18 				    pgprot_t prot)
19 {
20 	unsigned long offset = paddr & ~PAGE_MASK;
21 	unsigned long pfn = __phys_to_pfn(paddr);
22 	struct vm_struct *area;
23 	unsigned long vaddr;
24 	int err;
25 
26 	paddr &= PAGE_MASK;
27 
28 	WARN_ON(pfn_valid(pfn));
29 
30 	size = PAGE_ALIGN(offset + size);
31 
32 	area = get_vm_area(size, VM_IOREMAP);
33 	if (!area)
34 		return NULL;
35 
36 	vaddr = (unsigned long)area->addr;
37 	area->phys_addr = paddr;
38 
39 	err = ioremap_page_range(vaddr, vaddr + size, paddr, prot);
40 
41 	if (err) {
42 		vunmap((void *)vaddr);
43 		return NULL;
44 	}
45 
46 	flush_cache_vmap(vaddr, vaddr + size);
47 	return (void __iomem *)(offset + vaddr);
48 }
49 
50 void __iomem *xtensa_ioremap_nocache(unsigned long addr, unsigned long size)
51 {
52 	return xtensa_ioremap(addr, size, pgprot_noncached(PAGE_KERNEL));
53 }
54 EXPORT_SYMBOL(xtensa_ioremap_nocache);
55 
56 void __iomem *xtensa_ioremap_cache(unsigned long addr, unsigned long size)
57 {
58 	return xtensa_ioremap(addr, size, PAGE_KERNEL);
59 }
60 EXPORT_SYMBOL(xtensa_ioremap_cache);
61 
62 void xtensa_iounmap(volatile void __iomem *io_addr)
63 {
64 	void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
65 
66 	vunmap(addr);
67 }
68 EXPORT_SYMBOL(xtensa_iounmap);
69