arch/arm/mm/nommu.c

   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         phys_addr_t end = bank_phys_end(&meminfo.bank[meminfo.nr_banks - 1]);
  33         high_memory = __va(end - 1) + 1;
  34 }
  35
  36 /*
  37  * paging_init() sets up the page tables, initialises the zone memory
  38  * maps, and sets up the zero page, bad page and bad page tables.
  39  */
  40 void __init paging_init(struct machine_desc *mdesc)
  41 {
  42         bootmem_init();
  43 }
  44
  45 /*
  46  * We don't need to do anything here for nommu machines.
  47  */
  48 void setup_mm_for_reboot(void)
  49 {
  50 }
  51
  52 void flush_dcache_page(struct page *page)
  53 {
  54         __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
  55 }
  56 EXPORT_SYMBOL(flush_dcache_page);
  57
  58 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
  59                        unsigned long uaddr, void *dst, const void *src,
  60                        unsigned long len)
  61 {
  62         memcpy(dst, src, len);
  63         if (vma->vm_flags & VM_EXEC)
  64                 __cpuc_coherent_user_range(uaddr, uaddr + len);
  65 }
  66
  67 void __iomem *__arm_ioremap_pfn(unsigned long pfn, unsigned long offset,
  68                                 size_t size, unsigned int mtype)
  69 {
  70         if (pfn >= (0x100000000ULL >> PAGE_SHIFT))
  71                 return NULL;
  72         return (void __iomem *) (offset + (pfn << PAGE_SHIFT));
  73 }
  74 EXPORT_SYMBOL(__arm_ioremap_pfn);
  75
  76 void __iomem *__arm_ioremap_pfn_caller(unsigned long pfn, unsigned long offset,
  77                            size_t size, unsigned int mtype, void *caller)
  78 {
  79         return __arm_ioremap_pfn(pfn, offset, size, mtype);
  80 }
  81
  82 void __iomem *__arm_ioremap(unsigned long phys_addr, size_t size,
  83                             unsigned int mtype)
  84 {
  85         return (void __iomem *)phys_addr;
  86 }
  87 EXPORT_SYMBOL(__arm_ioremap);
  88
  89 void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
  90                                    unsigned int mtype, void *caller)
  91 {
  92         return __arm_ioremap(phys_addr, size, mtype);
  93 }
  94
  95 void __iounmap(volatile void __iomem *addr)
  96 {
  97 }
  98 EXPORT_SYMBOL(__iounmap);