xref: /openbmc/linux/arch/arm/mm/nommu.c (revision 7fe2f639)
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 void __init sanity_check_meminfo(void)
31 {
32 }
33 
34 /*
35  * paging_init() sets up the page tables, initialises the zone memory
36  * maps, and sets up the zero page, bad page and bad page tables.
37  */
38 void __init paging_init(struct machine_desc *mdesc)
39 {
40 	bootmem_init();
41 }
42 
43 /*
44  * We don't need to do anything here for nommu machines.
45  */
46 void setup_mm_for_reboot(char mode)
47 {
48 }
49 
50 void flush_dcache_page(struct page *page)
51 {
52 	__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
53 }
54 EXPORT_SYMBOL(flush_dcache_page);
55 
56 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
57 		       unsigned long uaddr, void *dst, const void *src,
58 		       unsigned long len)
59 {
60 	memcpy(dst, src, len);
61 	if (vma->vm_flags & VM_EXEC)
62 		__cpuc_coherent_user_range(uaddr, uaddr + len);
63 }
64 
65 void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
66 				size_t size, unsigned int mtype)
67 {
68 	if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
69 		return NULL;
70 	return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
71 }
72 EXPORT_SYMBOL(__arm_ioremap_pfn);
73 
74 void __iomem *__arm_ioremap_pfn_caller(unsigned long pfn, unsigned long offset,
75 			   size_t size, unsigned int mtype, void *caller)
76 {
77 	return __arm_ioremap_pfn(pfn, offset, size, mtype);
78 }
79 
80 void __iomem *__arm_ioremap(unsigned long phys_addr, size_t size,
81 			    unsigned int mtype)
82 {
83 	return (void __iomem *)phys_addr;
84 }
85 EXPORT_SYMBOL(__arm_ioremap);
86 
87 void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
88 				   unsigned int mtype, void *caller)
89 {
90 	return __arm_ioremap(phys_addr, size, mtype);
91 }
92 
93 void __iounmap(volatile void __iomem *addr)
94 {
95 }
96 EXPORT_SYMBOL(__iounmap);
97