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 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). 11 * 12 * Derived from "arch/i386/mm/init.c" 13 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 14 * 15 * Dave Engebretsen <engebret@us.ibm.com> 16 * Rework for PPC64 port. 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License 20 * as published by the Free Software Foundation; either version 21 * 2 of the License, or (at your option) any later version. 22 * 23 */ 24 25 #include <linux/signal.h> 26 #include <linux/sched.h> 27 #include <linux/kernel.h> 28 #include <linux/errno.h> 29 #include <linux/string.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/init.h> 37 #include <linux/delay.h> 38 #include <linux/bootmem.h> 39 #include <linux/highmem.h> 40 #include <linux/idr.h> 41 #include <linux/nodemask.h> 42 #include <linux/module.h> 43 44 #include <asm/pgalloc.h> 45 #include <asm/page.h> 46 #include <asm/prom.h> 47 #include <asm/lmb.h> 48 #include <asm/rtas.h> 49 #include <asm/io.h> 50 #include <asm/mmu_context.h> 51 #include <asm/pgtable.h> 52 #include <asm/mmu.h> 53 #include <asm/uaccess.h> 54 #include <asm/smp.h> 55 #include <asm/machdep.h> 56 #include <asm/tlb.h> 57 #include <asm/eeh.h> 58 #include <asm/processor.h> 59 #include <asm/mmzone.h> 60 #include <asm/cputable.h> 61 #include <asm/sections.h> 62 #include <asm/system.h> 63 #include <asm/iommu.h> 64 #include <asm/abs_addr.h> 65 #include <asm/vdso.h> 66 67 #include "mmu_decl.h" 68 69 unsigned long ioremap_bot = IMALLOC_BASE; 70 static unsigned long phbs_io_bot = PHBS_IO_BASE; 71 72 #ifdef CONFIG_PPC_ISERIES 73 74 void __iomem *ioremap(unsigned long addr, unsigned long size) 75 { 76 return (void __iomem *)addr; 77 } 78 79 extern void __iomem *__ioremap(unsigned long addr, unsigned long size, 80 unsigned long flags) 81 { 82 return (void __iomem *)addr; 83 } 84 85 void iounmap(volatile void __iomem *addr) 86 { 87 return; 88 } 89 90 #else 91 92 /* 93 * map_io_page currently only called by __ioremap 94 * map_io_page adds an entry to the ioremap page table 95 * and adds an entry to the HPT, possibly bolting it 96 */ 97 static int map_io_page(unsigned long ea, unsigned long pa, int flags) 98 { 99 pgd_t *pgdp; 100 pud_t *pudp; 101 pmd_t *pmdp; 102 pte_t *ptep; 103 104 if (mem_init_done) { 105 pgdp = pgd_offset_k(ea); 106 pudp = pud_alloc(&init_mm, pgdp, ea); 107 if (!pudp) 108 return -ENOMEM; 109 pmdp = pmd_alloc(&init_mm, pudp, ea); 110 if (!pmdp) 111 return -ENOMEM; 112 ptep = pte_alloc_kernel(pmdp, ea); 113 if (!ptep) 114 return -ENOMEM; 115 set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, 116 __pgprot(flags))); 117 } else { 118 /* 119 * If the mm subsystem is not fully up, we cannot create a 120 * linux page table entry for this mapping. Simply bolt an 121 * entry in the hardware page table. 122 * 123 */ 124 if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags, 125 mmu_virtual_psize)) { 126 printk(KERN_ERR "Failed to do bolted mapping IO " 127 "memory at %016lx !\n", pa); 128 return -ENOMEM; 129 } 130 } 131 return 0; 132 } 133 134 135 static void __iomem * __ioremap_com(unsigned long addr, unsigned long pa, 136 unsigned long ea, unsigned long size, 137 unsigned long flags) 138 { 139 unsigned long i; 140 141 if ((flags & _PAGE_PRESENT) == 0) 142 flags |= pgprot_val(PAGE_KERNEL); 143 144 for (i = 0; i < size; i += PAGE_SIZE) 145 if (map_io_page(ea+i, pa+i, flags)) 146 return NULL; 147 148 return (void __iomem *) (ea + (addr & ~PAGE_MASK)); 149 } 150 151 152 void __iomem * 153 ioremap(unsigned long addr, unsigned long size) 154 { 155 return __ioremap(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED); 156 } 157 158 void __iomem * __ioremap(unsigned long addr, unsigned long size, 159 unsigned long flags) 160 { 161 unsigned long pa, ea; 162 void __iomem *ret; 163 164 /* 165 * Choose an address to map it to. 166 * Once the imalloc system is running, we use it. 167 * Before that, we map using addresses going 168 * up from ioremap_bot. imalloc will use 169 * the addresses from ioremap_bot through 170 * IMALLOC_END 171 * 172 */ 173 pa = addr & PAGE_MASK; 174 size = PAGE_ALIGN(addr + size) - pa; 175 176 if ((size == 0) || (pa == 0)) 177 return NULL; 178 179 if (mem_init_done) { 180 struct vm_struct *area; 181 area = im_get_free_area(size); 182 if (area == NULL) 183 return NULL; 184 ea = (unsigned long)(area->addr); 185 ret = __ioremap_com(addr, pa, ea, size, flags); 186 if (!ret) 187 im_free(area->addr); 188 } else { 189 ea = ioremap_bot; 190 ret = __ioremap_com(addr, pa, ea, size, flags); 191 if (ret) 192 ioremap_bot += size; 193 } 194 return ret; 195 } 196 197 #define IS_PAGE_ALIGNED(_val) ((_val) == ((_val) & PAGE_MASK)) 198 199 int __ioremap_explicit(unsigned long pa, unsigned long ea, 200 unsigned long size, unsigned long flags) 201 { 202 struct vm_struct *area; 203 void __iomem *ret; 204 205 /* For now, require page-aligned values for pa, ea, and size */ 206 if (!IS_PAGE_ALIGNED(pa) || !IS_PAGE_ALIGNED(ea) || 207 !IS_PAGE_ALIGNED(size)) { 208 printk(KERN_ERR "unaligned value in %s\n", __FUNCTION__); 209 return 1; 210 } 211 212 if (!mem_init_done) { 213 /* Two things to consider in this case: 214 * 1) No records will be kept (imalloc, etc) that the region 215 * has been remapped 216 * 2) It won't be easy to iounmap() the region later (because 217 * of 1) 218 */ 219 ; 220 } else { 221 area = im_get_area(ea, size, 222 IM_REGION_UNUSED|IM_REGION_SUBSET|IM_REGION_EXISTS); 223 if (area == NULL) { 224 /* Expected when PHB-dlpar is in play */ 225 return 1; 226 } 227 if (ea != (unsigned long) area->addr) { 228 printk(KERN_ERR "unexpected addr return from " 229 "im_get_area\n"); 230 return 1; 231 } 232 } 233 234 ret = __ioremap_com(pa, pa, ea, size, flags); 235 if (ret == NULL) { 236 printk(KERN_ERR "ioremap_explicit() allocation failure !\n"); 237 return 1; 238 } 239 if (ret != (void *) ea) { 240 printk(KERN_ERR "__ioremap_com() returned unexpected addr\n"); 241 return 1; 242 } 243 244 return 0; 245 } 246 247 /* 248 * Unmap an IO region and remove it from imalloc'd list. 249 * Access to IO memory should be serialized by driver. 250 * This code is modeled after vmalloc code - unmap_vm_area() 251 * 252 * XXX what about calls before mem_init_done (ie python_countermeasures()) 253 */ 254 void iounmap(volatile void __iomem *token) 255 { 256 void *addr; 257 258 if (!mem_init_done) 259 return; 260 261 addr = (void *) ((unsigned long __force) token & PAGE_MASK); 262 263 im_free(addr); 264 } 265 266 static int iounmap_subset_regions(unsigned long addr, unsigned long size) 267 { 268 struct vm_struct *area; 269 270 /* Check whether subsets of this region exist */ 271 area = im_get_area(addr, size, IM_REGION_SUPERSET); 272 if (area == NULL) 273 return 1; 274 275 while (area) { 276 iounmap((void __iomem *) area->addr); 277 area = im_get_area(addr, size, 278 IM_REGION_SUPERSET); 279 } 280 281 return 0; 282 } 283 284 int iounmap_explicit(volatile void __iomem *start, unsigned long size) 285 { 286 struct vm_struct *area; 287 unsigned long addr; 288 int rc; 289 290 addr = (unsigned long __force) start & PAGE_MASK; 291 292 /* Verify that the region either exists or is a subset of an existing 293 * region. In the latter case, split the parent region to create 294 * the exact region 295 */ 296 area = im_get_area(addr, size, 297 IM_REGION_EXISTS | IM_REGION_SUBSET); 298 if (area == NULL) { 299 /* Determine whether subset regions exist. If so, unmap */ 300 rc = iounmap_subset_regions(addr, size); 301 if (rc) { 302 printk(KERN_ERR 303 "%s() cannot unmap nonexistent range 0x%lx\n", 304 __FUNCTION__, addr); 305 return 1; 306 } 307 } else { 308 iounmap((void __iomem *) area->addr); 309 } 310 /* 311 * FIXME! This can't be right: 312 iounmap(area->addr); 313 * Maybe it should be "iounmap(area);" 314 */ 315 return 0; 316 } 317 318 #endif 319 320 EXPORT_SYMBOL(ioremap); 321 EXPORT_SYMBOL(__ioremap); 322 EXPORT_SYMBOL(iounmap); 323 324 void __iomem * reserve_phb_iospace(unsigned long size) 325 { 326 void __iomem *virt_addr; 327 328 if (phbs_io_bot >= IMALLOC_BASE) 329 panic("reserve_phb_iospace(): phb io space overflow\n"); 330 331 virt_addr = (void __iomem *) phbs_io_bot; 332 phbs_io_bot += size; 333 334 return virt_addr; 335 } 336