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, pgprot_t prot) 117 { 118 unsigned long i; 119 120 /* We don't support the 4K PFN hack with ioremap */ 121 if (pgprot_val(prot) & H_PAGE_4K_PFN) 122 return NULL; 123 124 WARN_ON(pa & ~PAGE_MASK); 125 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 126 WARN_ON(size & ~PAGE_MASK); 127 128 for (i = 0; i < size; i += PAGE_SIZE) 129 if (map_kernel_page((unsigned long)ea + i, pa + i, prot)) 130 return NULL; 131 132 return (void __iomem *)ea; 133 } 134 135 /** 136 * __iounmap_from - Low level function to tear down the page tables 137 * for an IO mapping. This is used for mappings that 138 * are manipulated manually, like partial unmapping of 139 * PCI IOs or ISA space. 140 */ 141 void __iounmap_at(void *ea, unsigned long size) 142 { 143 WARN_ON(((unsigned long)ea) & ~PAGE_MASK); 144 WARN_ON(size & ~PAGE_MASK); 145 146 unmap_kernel_range((unsigned long)ea, size); 147 } 148 149 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, 150 pgprot_t prot, void *caller) 151 { 152 phys_addr_t paligned; 153 void __iomem *ret; 154 155 /* 156 * Choose an address to map it to. 157 * Once the imalloc system is running, we use it. 158 * Before that, we map using addresses going 159 * up from ioremap_bot. imalloc will use 160 * the addresses from ioremap_bot through 161 * IMALLOC_END 162 * 163 */ 164 paligned = addr & PAGE_MASK; 165 size = PAGE_ALIGN(addr + size) - paligned; 166 167 if ((size == 0) || (paligned == 0)) 168 return NULL; 169 170 if (slab_is_available()) { 171 struct vm_struct *area; 172 173 area = __get_vm_area_caller(size, VM_IOREMAP, 174 ioremap_bot, IOREMAP_END, 175 caller); 176 if (area == NULL) 177 return NULL; 178 179 area->phys_addr = paligned; 180 ret = __ioremap_at(paligned, area->addr, size, prot); 181 if (!ret) 182 vunmap(area->addr); 183 } else { 184 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot); 185 if (ret) 186 ioremap_bot += size; 187 } 188 189 if (ret) 190 ret += addr & ~PAGE_MASK; 191 return ret; 192 } 193 194 void __iomem * __ioremap(phys_addr_t addr, unsigned long size, 195 unsigned long flags) 196 { 197 return __ioremap_caller(addr, size, __pgprot(flags), __builtin_return_address(0)); 198 } 199 200 void __iomem * ioremap(phys_addr_t addr, unsigned long size) 201 { 202 pgprot_t prot = pgprot_noncached(PAGE_KERNEL); 203 void *caller = __builtin_return_address(0); 204 205 if (ppc_md.ioremap) 206 return ppc_md.ioremap(addr, size, prot, caller); 207 return __ioremap_caller(addr, size, prot, caller); 208 } 209 210 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) 211 { 212 pgprot_t prot = pgprot_noncached_wc(PAGE_KERNEL); 213 void *caller = __builtin_return_address(0); 214 215 if (ppc_md.ioremap) 216 return ppc_md.ioremap(addr, size, prot, caller); 217 return __ioremap_caller(addr, size, prot, caller); 218 } 219 220 void __iomem *ioremap_coherent(phys_addr_t addr, unsigned long size) 221 { 222 pgprot_t prot = pgprot_cached(PAGE_KERNEL); 223 void *caller = __builtin_return_address(0); 224 225 if (ppc_md.ioremap) 226 return ppc_md.ioremap(addr, size, prot, caller); 227 return __ioremap_caller(addr, size, prot, caller); 228 } 229 230 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, 231 unsigned long flags) 232 { 233 pte_t pte = __pte(flags); 234 void *caller = __builtin_return_address(0); 235 236 /* writeable implies dirty for kernel addresses */ 237 if (pte_write(pte)) 238 pte = pte_mkdirty(pte); 239 240 /* we don't want to let _PAGE_EXEC leak out */ 241 pte = pte_exprotect(pte); 242 /* 243 * Force kernel mapping. 244 */ 245 pte = pte_mkprivileged(pte); 246 247 if (ppc_md.ioremap) 248 return ppc_md.ioremap(addr, size, pte_pgprot(pte), caller); 249 return __ioremap_caller(addr, size, pte_pgprot(pte), caller); 250 } 251 252 253 /* 254 * Unmap an IO region and remove it from imalloc'd list. 255 * Access to IO memory should be serialized by driver. 256 */ 257 void __iounmap(volatile void __iomem *token) 258 { 259 void *addr; 260 261 if (!slab_is_available()) 262 return; 263 264 addr = (void *) ((unsigned long __force) 265 PCI_FIX_ADDR(token) & PAGE_MASK); 266 if ((unsigned long)addr < ioremap_bot) { 267 printk(KERN_WARNING "Attempt to iounmap early bolted mapping" 268 " at 0x%p\n", addr); 269 return; 270 } 271 vunmap(addr); 272 } 273 274 void iounmap(volatile void __iomem *token) 275 { 276 if (ppc_md.iounmap) 277 ppc_md.iounmap(token); 278 else 279 __iounmap(token); 280 } 281 282 EXPORT_SYMBOL(ioremap); 283 EXPORT_SYMBOL(ioremap_wc); 284 EXPORT_SYMBOL(ioremap_prot); 285 EXPORT_SYMBOL(__ioremap); 286 EXPORT_SYMBOL(__ioremap_at); 287 EXPORT_SYMBOL(iounmap); 288 EXPORT_SYMBOL(__iounmap); 289 EXPORT_SYMBOL(__iounmap_at); 290 291 #ifndef __PAGETABLE_PUD_FOLDED 292 /* 4 level page table */ 293 struct page *pgd_page(pgd_t pgd) 294 { 295 if (pgd_huge(pgd)) 296 return pte_page(pgd_pte(pgd)); 297 return virt_to_page(pgd_page_vaddr(pgd)); 298 } 299 #endif 300 301 struct page *pud_page(pud_t pud) 302 { 303 if (pud_huge(pud)) 304 return pte_page(pud_pte(pud)); 305 return virt_to_page(pud_page_vaddr(pud)); 306 } 307 308 /* 309 * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags 310 * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address. 311 */ 312 struct page *pmd_page(pmd_t pmd) 313 { 314 if (pmd_large(pmd) || pmd_huge(pmd) || pmd_devmap(pmd)) 315 return pte_page(pmd_pte(pmd)); 316 return virt_to_page(pmd_page_vaddr(pmd)); 317 } 318 319 #ifdef CONFIG_STRICT_KERNEL_RWX 320 void mark_rodata_ro(void) 321 { 322 if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) { 323 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n"); 324 return; 325 } 326 327 if (radix_enabled()) 328 radix__mark_rodata_ro(); 329 else 330 hash__mark_rodata_ro(); 331 } 332 333 void mark_initmem_nx(void) 334 { 335 if (radix_enabled()) 336 radix__mark_initmem_nx(); 337 else 338 hash__mark_initmem_nx(); 339 } 340 #endif 341