xref: /linux/arch/arm/mm/nommu.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 /*
2  *  linux/arch/arm/mm/nommu.c
3  *
4  * ARM uCLinux supporting functions.
5  */
6 #include <linux/module.h>
7 #include <linux/mm.h>
8 #include <linux/pagemap.h>
9 #include <linux/io.h>
10 #include <linux/memblock.h>
11 
12 #include <asm/cacheflush.h>
13 #include <asm/sections.h>
14 #include <asm/page.h>
15 #include <asm/setup.h>
16 #include <asm/mach/arch.h>
17 
18 #include "mm.h"
19 
20 void __init arm_mm_memblock_reserve(void)
21 {
22 	/*
23 	 * Register the exception vector page.
24 	 * some architectures which the DRAM is the exception vector to trap,
25 	 * alloc_page breaks with error, although it is not NULL, but "0."
26 	 */
27 	memblock_reserve(CONFIG_VECTORS_BASE, PAGE_SIZE);
28 }
29 
30 /*
31  * paging_init() sets up the page tables, initialises the zone memory
32  * maps, and sets up the zero page, bad page and bad page tables.
33  */
34 void __init paging_init(struct machine_desc *mdesc)
35 {
36 	bootmem_init();
37 }
38 
39 /*
40  * We don't need to do anything here for nommu machines.
41  */
42 void setup_mm_for_reboot(char mode)
43 {
44 }
45 
46 void flush_dcache_page(struct page *page)
47 {
48 	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
49 }
50 EXPORT_SYMBOL(flush_dcache_page);
51 
52 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
53 		       unsigned long uaddr, void *dst, const void *src,
54 		       unsigned long len)
55 {
56 	memcpy(dst, src, len);
57 	if (vma->vm_flags & VM_EXEC)
58 		__cpuc_coherent_user_range(uaddr, uaddr + len);
59 }
60 
61 void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
62 				size_t size, unsigned int mtype)
63 {
64 	if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
65 		return NULL;
66 	return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
67 }
68 EXPORT_SYMBOL(__arm_ioremap_pfn);
69 
70 void __iomem *__arm_ioremap_pfn_caller(unsigned long pfn, unsigned long offset,
71 			   size_t size, unsigned int mtype, void *caller)
72 {
73 	return __arm_ioremap_pfn(pfn, offset, size, mtype);
74 }
75 
76 void __iomem *__arm_ioremap(unsigned long phys_addr, size_t size,
77 			    unsigned int mtype)
78 {
79 	return (void __iomem *)phys_addr;
80 }
81 EXPORT_SYMBOL(__arm_ioremap);
82 
83 void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
84 				   unsigned int mtype, void *caller)
85 {
86 	return __arm_ioremap(phys_addr, size, mtype);
87 }
88 
89 void __iounmap(volatile void __iomem *addr)
90 {
91 }
92 EXPORT_SYMBOL(__iounmap);
93