1 /* 2 * This file contains ioremap and related functions for 64-bit machines. 3 * 4 * Derived from arch/ppc64/mm/init.c 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * 7 * Modifications by Paul Mackerras (PowerMac) (paulus@samba.org) 8 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 9 * Copyright (C) 1996 Paul Mackerras 10 * 11 * Derived from "arch/i386/mm/init.c" 12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 13 * 14 * Dave Engebretsen <engebret@us.ibm.com> 15 * Rework for PPC64 port. 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License 19 * as published by the Free Software Foundation; either version 20 * 2 of the License, or (at your option) any later version. 21 * 22 */ 23 24 #include <linux/signal.h> 25 #include <linux/sched.h> 26 #include <linux/kernel.h> 27 #include <linux/errno.h> 28 #include <linux/string.h> 29 #include <linux/export.h> 30 #include <linux/types.h> 31 #include <linux/mman.h> 32 #include <linux/mm.h> 33 #include <linux/swap.h> 34 #include <linux/stddef.h> 35 #include <linux/vmalloc.h> 36 #include <linux/slab.h> 37 #include <linux/hugetlb.h> 38 39 #include <asm/pgalloc.h> 40 #include <asm/page.h> 41 #include <asm/prom.h> 42 #include <asm/io.h> 43 #include <asm/mmu_context.h> 44 #include <asm/pgtable.h> 45 #include <asm/mmu.h> 46 #include <asm/smp.h> 47 #include <asm/machdep.h> 48 #include <asm/tlb.h> 49 #include <asm/processor.h> 50 #include <asm/cputable.h> 51 #include <asm/sections.h> 52 #include <asm/firmware.h> 53 #include <asm/dma.h> 54 55 #include "mmu_decl.h" 56 57 58 #ifdef CONFIG_PPC_BOOK3S_64 59 /* 60 * partition table and process table for ISA 3.0 61 */ 62 struct prtb_entry *process_tb; 63 struct patb_entry *partition_tb; 64 /* 65 * page table size 66 */ 67 unsigned long __pte_index_size; 68 EXPORT_SYMBOL(__pte_index_size); 69 unsigned long __pmd_index_size; 70 EXPORT_SYMBOL(__pmd_index_size); 71 unsigned long __pud_index_size; 72 EXPORT_SYMBOL(__pud_index_size); 73 unsigned long __pgd_index_size; 74 EXPORT_SYMBOL(__pgd_index_size); 75 unsigned long __pud_cache_index; 76 EXPORT_SYMBOL(__pud_cache_index); 77 unsigned long __pte_table_size; 78 EXPORT_SYMBOL(__pte_table_size); 79 unsigned long __pmd_table_size; 80 EXPORT_SYMBOL(__pmd_table_size); 81 unsigned long __pud_table_size; 82 EXPORT_SYMBOL(__pud_table_size); 83 unsigned long __pgd_table_size; 84 EXPORT_SYMBOL(__pgd_table_size); 85 unsigned long __pmd_val_bits; 86 EXPORT_SYMBOL(__pmd_val_bits); 87 unsigned long __pud_val_bits; 88 EXPORT_SYMBOL(__pud_val_bits); 89 unsigned long __pgd_val_bits; 90 EXPORT_SYMBOL(__pgd_val_bits); 91 unsigned long __kernel_virt_start; 92 EXPORT_SYMBOL(__kernel_virt_start); 93 unsigned long __kernel_virt_size; 94 EXPORT_SYMBOL(__kernel_virt_size); 95 unsigned long __vmalloc_start; 96 EXPORT_SYMBOL(__vmalloc_start); 97 unsigned long __vmalloc_end; 98 EXPORT_SYMBOL(__vmalloc_end); 99 unsigned long __kernel_io_start; 100 EXPORT_SYMBOL(__kernel_io_start); 101 struct page *vmemmap; 102 EXPORT_SYMBOL(vmemmap); 103 unsigned long __pte_frag_nr; 104 EXPORT_SYMBOL(__pte_frag_nr); 105 unsigned long __pte_frag_size_shift; 106 EXPORT_SYMBOL(__pte_frag_size_shift); 107 unsigned long ioremap_bot; 108 #else /* !CONFIG_PPC_BOOK3S_64 */ 109 unsigned long ioremap_bot = IOREMAP_BASE; 110 #endif 111 112 /** 113 * __ioremap_at - Low level function to establish the page tables 114 * for an IO mapping 115 */ 116 void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size, 117 unsigned long flags) 118 { 119 unsigned long i; 120 121 /* Make sure we have the base flags */ 122 if ((flags & _PAGE_PRESENT) == 0) 123 flags |= pgprot_val(PAGE_KERNEL); 124 125 /* We don't support the 4K PFN hack with ioremap */ 126 if (flags & H_PAGE_4K_PFN) 127 return NULL; 128 129 WARN_ON(pa & ~PAGE_MASK); 130 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 131 WARN_ON(size & ~PAGE_MASK); 132 133 for (i = 0; i < size; i += PAGE_SIZE) 134 if (map_kernel_page((unsigned long)ea+i, pa+i, flags)) 135 return NULL; 136 137 return (void __iomem *)ea; 138 } 139 140 /** 141 * __iounmap_from - Low level function to tear down the page tables 142 * for an IO mapping. This is used for mappings that 143 * are manipulated manually, like partial unmapping of 144 * PCI IOs or ISA space. 145 */ 146 void __iounmap_at(void *ea, unsigned long size) 147 { 148 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 149 WARN_ON(size & ~PAGE_MASK); 150 151 unmap_kernel_range((unsigned long)ea, size); 152 } 153 154 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, 155 unsigned long flags, void *caller) 156 { 157 phys_addr_t paligned; 158 void __iomem *ret; 159 160 /* 161 * Choose an address to map it to. 162 * Once the imalloc system is running, we use it. 163 * Before that, we map using addresses going 164 * up from ioremap_bot. imalloc will use 165 * the addresses from ioremap_bot through 166 * IMALLOC_END 167 * 168 */ 169 paligned = addr & PAGE_MASK; 170 size = PAGE_ALIGN(addr + size) - paligned; 171 172 if ((size == 0) || (paligned == 0)) 173 return NULL; 174 175 if (slab_is_available()) { 176 struct vm_struct *area; 177 178 area = __get_vm_area_caller(size, VM_IOREMAP, 179 ioremap_bot, IOREMAP_END, 180 caller); 181 if (area == NULL) 182 return NULL; 183 184 area->phys_addr = paligned; 185 ret = __ioremap_at(paligned, area->addr, size, flags); 186 if (!ret) 187 vunmap(area->addr); 188 } else { 189 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, flags); 190 if (ret) 191 ioremap_bot += size; 192 } 193 194 if (ret) 195 ret += addr & ~PAGE_MASK; 196 return ret; 197 } 198 199 void __iomem * __ioremap(phys_addr_t addr, unsigned long size, 200 unsigned long flags) 201 { 202 return __ioremap_caller(addr, size, flags, __builtin_return_address(0)); 203 } 204 205 void __iomem * ioremap(phys_addr_t addr, unsigned long size) 206 { 207 unsigned long flags = pgprot_val(pgprot_noncached(__pgprot(0))); 208 void *caller = __builtin_return_address(0); 209 210 if (ppc_md.ioremap) 211 return ppc_md.ioremap(addr, size, flags, caller); 212 return __ioremap_caller(addr, size, flags, caller); 213 } 214 215 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) 216 { 217 unsigned long flags = pgprot_val(pgprot_noncached_wc(__pgprot(0))); 218 void *caller = __builtin_return_address(0); 219 220 if (ppc_md.ioremap) 221 return ppc_md.ioremap(addr, size, flags, caller); 222 return __ioremap_caller(addr, size, flags, caller); 223 } 224 225 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, 226 unsigned long flags) 227 { 228 void *caller = __builtin_return_address(0); 229 230 /* writeable implies dirty for kernel addresses */ 231 if (flags & _PAGE_WRITE) 232 flags |= _PAGE_DIRTY; 233 234 /* we don't want to let _PAGE_EXEC leak out */ 235 flags &= ~_PAGE_EXEC; 236 /* 237 * Force kernel mapping. 238 */ 239 flags &= ~_PAGE_USER; 240 flags |= _PAGE_PRIVILEGED; 241 242 if (ppc_md.ioremap) 243 return ppc_md.ioremap(addr, size, flags, caller); 244 return __ioremap_caller(addr, size, flags, caller); 245 } 246 247 248 /* 249 * Unmap an IO region and remove it from imalloc'd list. 250 * Access to IO memory should be serialized by driver. 251 */ 252 void __iounmap(volatile void __iomem *token) 253 { 254 void *addr; 255 256 if (!slab_is_available()) 257 return; 258 259 addr = (void *) ((unsigned long __force) 260 PCI_FIX_ADDR(token) & PAGE_MASK); 261 if ((unsigned long)addr < ioremap_bot) { 262 printk(KERN_WARNING "Attempt to iounmap early bolted mapping" 263 " at 0x%p\n", addr); 264 return; 265 } 266 vunmap(addr); 267 } 268 269 void iounmap(volatile void __iomem *token) 270 { 271 if (ppc_md.iounmap) 272 ppc_md.iounmap(token); 273 else 274 __iounmap(token); 275 } 276 277 EXPORT_SYMBOL(ioremap); 278 EXPORT_SYMBOL(ioremap_wc); 279 EXPORT_SYMBOL(ioremap_prot); 280 EXPORT_SYMBOL(__ioremap); 281 EXPORT_SYMBOL(__ioremap_at); 282 EXPORT_SYMBOL(iounmap); 283 EXPORT_SYMBOL(__iounmap); 284 EXPORT_SYMBOL(__iounmap_at); 285 286 #ifndef __PAGETABLE_PUD_FOLDED 287 /* 4 level page table */ 288 struct page *pgd_page(pgd_t pgd) 289 { 290 if (pgd_huge(pgd)) 291 return pte_page(pgd_pte(pgd)); 292 return virt_to_page(pgd_page_vaddr(pgd)); 293 } 294 #endif 295 296 struct page *pud_page(pud_t pud) 297 { 298 if (pud_huge(pud)) 299 return pte_page(pud_pte(pud)); 300 return virt_to_page(pud_page_vaddr(pud)); 301 } 302 303 /* 304 * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags 305 * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address. 306 */ 307 struct page *pmd_page(pmd_t pmd) 308 { 309 if (pmd_trans_huge(pmd) || pmd_huge(pmd) || pmd_devmap(pmd)) 310 return pte_page(pmd_pte(pmd)); 311 return virt_to_page(pmd_page_vaddr(pmd)); 312 } 313 314 #ifdef CONFIG_STRICT_KERNEL_RWX 315 void mark_rodata_ro(void) 316 { 317 if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) { 318 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n"); 319 return; 320 } 321 322 if (radix_enabled()) 323 radix__mark_rodata_ro(); 324 else 325 hash__mark_rodata_ro(); 326 } 327 328 void mark_initmem_nx(void) 329 { 330 if (radix_enabled()) 331 radix__mark_initmem_nx(); 332 else 333 hash__mark_initmem_nx(); 334 } 335 #endif 336