xref: /openbmc/linux/arch/csky/mm/ioremap.c (revision 0c874100)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #include <linux/export.h>
5 #include <linux/mm.h>
6 #include <linux/vmalloc.h>
7 #include <linux/io.h>
8 
9 #include <asm/pgtable.h>
10 
11 void __iomem *ioremap(phys_addr_t addr, size_t size)
12 {
13 	phys_addr_t last_addr;
14 	unsigned long offset, vaddr;
15 	struct vm_struct *area;
16 	pgprot_t prot;
17 
18 	last_addr = addr + size - 1;
19 	if (!size || last_addr < addr)
20 		return NULL;
21 
22 	offset = addr & (~PAGE_MASK);
23 	addr &= PAGE_MASK;
24 	size = PAGE_ALIGN(size + offset);
25 
26 	area = get_vm_area_caller(size, VM_ALLOC, __builtin_return_address(0));
27 	if (!area)
28 		return NULL;
29 
30 	vaddr = (unsigned long)area->addr;
31 
32 	prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE |
33 			_PAGE_GLOBAL | _CACHE_UNCACHED);
34 
35 	if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
36 		free_vm_area(area);
37 		return NULL;
38 	}
39 
40 	return (void __iomem *)(vaddr + offset);
41 }
42 EXPORT_SYMBOL(ioremap);
43 
44 void iounmap(void __iomem *addr)
45 {
46 	vunmap((void *)((unsigned long)addr & PAGE_MASK));
47 }
48 EXPORT_SYMBOL(iounmap);
49