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/bootmem.h> 10 11 #include <asm/cacheflush.h> 12 #include <asm/io.h> 13 #include <asm/page.h> 14 #include <asm/mach/arch.h> 15 16 #include "mm.h" 17 18 extern void _stext, __data_start, _end; 19 20 /* 21 * Reserve the various regions of node 0 22 */ 23 void __init reserve_node_zero(pg_data_t *pgdat) 24 { 25 /* 26 * Register the kernel text and data with bootmem. 27 * Note that this can only be in node 0. 28 */ 29 #ifdef CONFIG_XIP_KERNEL 30 reserve_bootmem_node(pgdat, __pa(&__data_start), &_end - &__data_start); 31 #else 32 reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext); 33 #endif 34 35 /* 36 * Register the exception vector page. 37 * some architectures which the DRAM is the exception vector to trap, 38 * alloc_page breaks with error, although it is not NULL, but "0." 39 */ 40 reserve_bootmem_node(pgdat, CONFIG_VECTORS_BASE, PAGE_SIZE); 41 } 42 43 /* 44 * paging_init() sets up the page tables, initialises the zone memory 45 * maps, and sets up the zero page, bad page and bad page tables. 46 */ 47 void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc) 48 { 49 bootmem_init(mi); 50 } 51 52 /* 53 * We don't need to do anything here for nommu machines. 54 */ 55 void setup_mm_for_reboot(char mode) 56 { 57 } 58 59 void flush_dcache_page(struct page *page) 60 { 61 __cpuc_flush_dcache_page(page_address(page)); 62 } 63 EXPORT_SYMBOL(flush_dcache_page); 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(unsigned long phys_addr, size_t size, 75 unsigned int mtype) 76 { 77 return (void __iomem *)phys_addr; 78 } 79 EXPORT_SYMBOL(__arm_ioremap); 80 81 void __iounmap(volatile void __iomem *addr) 82 { 83 } 84 EXPORT_SYMBOL(__iounmap); 85