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 #include <asm/firmware.h> 67 68 #include "mmu_decl.h" 69 70 unsigned long ioremap_bot = IMALLOC_BASE; 71 static unsigned long phbs_io_bot = PHBS_IO_BASE; 72 73 /* 74 * map_io_page currently only called by __ioremap 75 * map_io_page adds an entry to the ioremap page table 76 * and adds an entry to the HPT, possibly bolting it 77 */ 78 static int map_io_page(unsigned long ea, unsigned long pa, int flags) 79 { 80 pgd_t *pgdp; 81 pud_t *pudp; 82 pmd_t *pmdp; 83 pte_t *ptep; 84 85 if (mem_init_done) { 86 pgdp = pgd_offset_k(ea); 87 pudp = pud_alloc(&init_mm, pgdp, ea); 88 if (!pudp) 89 return -ENOMEM; 90 pmdp = pmd_alloc(&init_mm, pudp, ea); 91 if (!pmdp) 92 return -ENOMEM; 93 ptep = pte_alloc_kernel(pmdp, ea); 94 if (!ptep) 95 return -ENOMEM; 96 set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, 97 __pgprot(flags))); 98 } else { 99 /* 100 * If the mm subsystem is not fully up, we cannot create a 101 * linux page table entry for this mapping. Simply bolt an 102 * entry in the hardware page table. 103 * 104 */ 105 if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags, 106 mmu_io_psize)) { 107 printk(KERN_ERR "Failed to do bolted mapping IO " 108 "memory at %016lx !\n", pa); 109 return -ENOMEM; 110 } 111 } 112 return 0; 113 } 114 115 116 static void __iomem * __ioremap_com(phys_addr_t addr, unsigned long pa, 117 unsigned long ea, unsigned long size, 118 unsigned long flags) 119 { 120 unsigned long i; 121 122 if ((flags & _PAGE_PRESENT) == 0) 123 flags |= pgprot_val(PAGE_KERNEL); 124 125 for (i = 0; i < size; i += PAGE_SIZE) 126 if (map_io_page(ea+i, pa+i, flags)) 127 return NULL; 128 129 return (void __iomem *) (ea + (addr & ~PAGE_MASK)); 130 } 131 132 void __iomem * __ioremap(phys_addr_t addr, unsigned long size, 133 unsigned long flags) 134 { 135 unsigned long pa, ea; 136 void __iomem *ret; 137 138 /* 139 * Choose an address to map it to. 140 * Once the imalloc system is running, we use it. 141 * Before that, we map using addresses going 142 * up from ioremap_bot. imalloc will use 143 * the addresses from ioremap_bot through 144 * IMALLOC_END 145 * 146 */ 147 pa = addr & PAGE_MASK; 148 size = PAGE_ALIGN(addr + size) - pa; 149 150 if ((size == 0) || (pa == 0)) 151 return NULL; 152 153 if (mem_init_done) { 154 struct vm_struct *area; 155 area = im_get_free_area(size); 156 if (area == NULL) 157 return NULL; 158 ea = (unsigned long)(area->addr); 159 ret = __ioremap_com(addr, pa, ea, size, flags); 160 if (!ret) 161 im_free(area->addr); 162 } else { 163 ea = ioremap_bot; 164 ret = __ioremap_com(addr, pa, ea, size, flags); 165 if (ret) 166 ioremap_bot += size; 167 } 168 return ret; 169 } 170 171 172 void __iomem * ioremap(phys_addr_t addr, unsigned long size) 173 { 174 unsigned long flags = _PAGE_NO_CACHE | _PAGE_GUARDED; 175 176 if (ppc_md.ioremap) 177 return ppc_md.ioremap(addr, size, flags); 178 return __ioremap(addr, size, flags); 179 } 180 181 void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size, 182 unsigned long flags) 183 { 184 if (ppc_md.ioremap) 185 return ppc_md.ioremap(addr, size, flags); 186 return __ioremap(addr, size, flags); 187 } 188 189 190 #define IS_PAGE_ALIGNED(_val) ((_val) == ((_val) & PAGE_MASK)) 191 192 int __ioremap_explicit(phys_addr_t pa, unsigned long ea, 193 unsigned long size, unsigned long flags) 194 { 195 struct vm_struct *area; 196 void __iomem *ret; 197 198 /* For now, require page-aligned values for pa, ea, and size */ 199 if (!IS_PAGE_ALIGNED(pa) || !IS_PAGE_ALIGNED(ea) || 200 !IS_PAGE_ALIGNED(size)) { 201 printk(KERN_ERR "unaligned value in %s\n", __FUNCTION__); 202 return 1; 203 } 204 205 if (!mem_init_done) { 206 /* Two things to consider in this case: 207 * 1) No records will be kept (imalloc, etc) that the region 208 * has been remapped 209 * 2) It won't be easy to iounmap() the region later (because 210 * of 1) 211 */ 212 ; 213 } else { 214 area = im_get_area(ea, size, 215 IM_REGION_UNUSED|IM_REGION_SUBSET|IM_REGION_EXISTS); 216 if (area == NULL) { 217 /* Expected when PHB-dlpar is in play */ 218 return 1; 219 } 220 if (ea != (unsigned long) area->addr) { 221 printk(KERN_ERR "unexpected addr return from " 222 "im_get_area\n"); 223 return 1; 224 } 225 } 226 227 ret = __ioremap_com(pa, pa, ea, size, flags); 228 if (ret == NULL) { 229 printk(KERN_ERR "ioremap_explicit() allocation failure !\n"); 230 return 1; 231 } 232 if (ret != (void *) ea) { 233 printk(KERN_ERR "__ioremap_com() returned unexpected addr\n"); 234 return 1; 235 } 236 237 return 0; 238 } 239 240 /* 241 * Unmap an IO region and remove it from imalloc'd list. 242 * Access to IO memory should be serialized by driver. 243 * This code is modeled after vmalloc code - unmap_vm_area() 244 * 245 * XXX what about calls before mem_init_done (ie python_countermeasures()) 246 */ 247 void __iounmap(volatile void __iomem *token) 248 { 249 void *addr; 250 251 if (!mem_init_done) 252 return; 253 254 addr = (void *) ((unsigned long __force) token & PAGE_MASK); 255 256 im_free(addr); 257 } 258 259 void iounmap(volatile void __iomem *token) 260 { 261 if (ppc_md.iounmap) 262 ppc_md.iounmap(token); 263 else 264 __iounmap(token); 265 } 266 267 static int iounmap_subset_regions(unsigned long addr, unsigned long size) 268 { 269 struct vm_struct *area; 270 271 /* Check whether subsets of this region exist */ 272 area = im_get_area(addr, size, IM_REGION_SUPERSET); 273 if (area == NULL) 274 return 1; 275 276 while (area) { 277 iounmap((void __iomem *) area->addr); 278 area = im_get_area(addr, size, 279 IM_REGION_SUPERSET); 280 } 281 282 return 0; 283 } 284 285 int __iounmap_explicit(volatile void __iomem *start, unsigned long size) 286 { 287 struct vm_struct *area; 288 unsigned long addr; 289 int rc; 290 291 addr = (unsigned long __force) start & PAGE_MASK; 292 293 /* Verify that the region either exists or is a subset of an existing 294 * region. In the latter case, split the parent region to create 295 * the exact region 296 */ 297 area = im_get_area(addr, size, 298 IM_REGION_EXISTS | IM_REGION_SUBSET); 299 if (area == NULL) { 300 /* Determine whether subset regions exist. If so, unmap */ 301 rc = iounmap_subset_regions(addr, size); 302 if (rc) { 303 printk(KERN_ERR 304 "%s() cannot unmap nonexistent range 0x%lx\n", 305 __FUNCTION__, addr); 306 return 1; 307 } 308 } else { 309 iounmap((void __iomem *) area->addr); 310 } 311 /* 312 * FIXME! This can't be right: 313 iounmap(area->addr); 314 * Maybe it should be "iounmap(area);" 315 */ 316 return 0; 317 } 318 319 EXPORT_SYMBOL(ioremap); 320 EXPORT_SYMBOL(ioremap_flags); 321 EXPORT_SYMBOL(__ioremap); 322 EXPORT_SYMBOL(iounmap); 323 EXPORT_SYMBOL(__iounmap); 324 325 static DEFINE_SPINLOCK(phb_io_lock); 326 327 void __iomem * reserve_phb_iospace(unsigned long size) 328 { 329 void __iomem *virt_addr; 330 331 if (phbs_io_bot >= IMALLOC_BASE) 332 panic("reserve_phb_iospace(): phb io space overflow\n"); 333 334 spin_lock(&phb_io_lock); 335 virt_addr = (void __iomem *) phbs_io_bot; 336 phbs_io_bot += size; 337 spin_unlock(&phb_io_lock); 338 339 return virt_addr; 340 } 341