1 /* 2 * linux/arch/m68k/mm/sun3kmap.c 3 * 4 * Copyright (C) 2002 Sam Creasey <sammy@sammy.net> 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file COPYING in the main directory of this archive 8 * for more details. 9 */ 10 11 #include <linux/types.h> 12 #include <linux/kernel.h> 13 #include <linux/mm.h> 14 #include <linux/vmalloc.h> 15 16 #include <asm/page.h> 17 #include <asm/pgtable.h> 18 #include <asm/io.h> 19 #include <asm/sun3mmu.h> 20 21 #undef SUN3_KMAP_DEBUG 22 23 #ifdef SUN3_KMAP_DEBUG 24 extern void print_pte_vaddr(unsigned long vaddr); 25 #endif 26 27 extern void mmu_emu_map_pmeg (int context, int vaddr); 28 29 static inline void do_page_mapin(unsigned long phys, unsigned long virt, 30 unsigned long type) 31 { 32 unsigned long pte; 33 pte_t ptep; 34 35 ptep = pfn_pte(phys >> PAGE_SHIFT, PAGE_KERNEL); 36 pte = pte_val(ptep); 37 pte |= type; 38 39 sun3_put_pte(virt, pte); 40 41 #ifdef SUN3_KMAP_DEBUG 42 print_pte_vaddr(virt); 43 #endif 44 45 } 46 47 static inline void do_pmeg_mapin(unsigned long phys, unsigned long virt, 48 unsigned long type, int pages) 49 { 50 51 if(sun3_get_segmap(virt & ~SUN3_PMEG_MASK) == SUN3_INVALID_PMEG) 52 mmu_emu_map_pmeg(sun3_get_context(), virt); 53 54 while(pages) { 55 do_page_mapin(phys, virt, type); 56 phys += PAGE_SIZE; 57 virt += PAGE_SIZE; 58 pages--; 59 } 60 } 61 62 void *sun3_ioremap(unsigned long phys, unsigned long size, 63 unsigned long type) 64 { 65 struct vm_struct *area; 66 unsigned long offset, virt, ret; 67 int pages; 68 69 if(!size) 70 return NULL; 71 72 /* page align */ 73 offset = phys & (PAGE_SIZE-1); 74 phys &= ~(PAGE_SIZE-1); 75 76 size += offset; 77 size = PAGE_ALIGN(size); 78 if((area = get_vm_area(size, VM_IOREMAP)) == NULL) 79 return NULL; 80 81 #ifdef SUN3_KMAP_DEBUG 82 printk("ioremap: got virt %p size %lx(%lx)\n", 83 area->addr, size, area->size); 84 #endif 85 86 pages = size / PAGE_SIZE; 87 virt = (unsigned long)area->addr; 88 ret = virt + offset; 89 90 while(pages) { 91 int seg_pages; 92 93 seg_pages = (SUN3_PMEG_SIZE - (virt & SUN3_PMEG_MASK)) / PAGE_SIZE; 94 if(seg_pages > pages) 95 seg_pages = pages; 96 97 do_pmeg_mapin(phys, virt, type, seg_pages); 98 99 pages -= seg_pages; 100 phys += seg_pages * PAGE_SIZE; 101 virt += seg_pages * PAGE_SIZE; 102 } 103 104 return (void *)ret; 105 106 } 107 108 109 void *__ioremap(unsigned long phys, unsigned long size, int cache) 110 { 111 112 return sun3_ioremap(phys, size, SUN3_PAGE_TYPE_IO); 113 114 } 115 116 void iounmap(void *addr) 117 { 118 vfree((void *)(PAGE_MASK & (unsigned long)addr)); 119 } 120 121 /* sun3_map_test(addr, val) -- Reads a byte from addr, storing to val, 122 * trapping the potential read fault. Returns 0 if the access faulted, 123 * 1 on success. 124 * 125 * This function is primarily used to check addresses on the VME bus. 126 * 127 * Mucking with the page fault handler seems a little hackish to me, but 128 * SunOS, NetBSD, and Mach all implemented this check in such a manner, 129 * so I figure we're allowed. 130 */ 131 int sun3_map_test(unsigned long addr, char *val) 132 { 133 int ret = 0; 134 135 __asm__ __volatile__ 136 (".globl _sun3_map_test_start\n" 137 "_sun3_map_test_start:\n" 138 "1: moveb (%2), (%0)\n" 139 " moveq #1, %1\n" 140 "2:\n" 141 ".section .fixup,\"ax\"\n" 142 ".even\n" 143 "3: moveq #0, %1\n" 144 " jmp 2b\n" 145 ".previous\n" 146 ".section __ex_table,\"a\"\n" 147 ".align 4\n" 148 ".long 1b,3b\n" 149 ".previous\n" 150 ".globl _sun3_map_test_end\n" 151 "_sun3_map_test_end:\n" 152 : "=a"(val), "=r"(ret) 153 : "a"(addr)); 154 155 return ret; 156 } 157