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 70unsigned long ioremap_bot = IMALLOC_BASE; 71static 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 */ 78static 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 116static 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 132void __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 172void __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 181void __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 192int __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 240void __iounmap(volatile void __iomem *token) 241{ 242 void *addr; 243 244 if (!mem_init_done) 245 return; 246 247 addr = (void *) ((unsigned long __force) token & PAGE_MASK); 248 249 im_free(addr); 250} 251 252void iounmap(volatile void __iomem *token) 253{ 254 if (ppc_md.iounmap) 255 ppc_md.iounmap(token); 256 else 257 __iounmap(token); 258} 259 260static int iounmap_subset_regions(unsigned long addr, unsigned long size) 261{ 262 struct vm_struct *area; 263 264 /* Check whether subsets of this region exist */ 265 area = im_get_area(addr, size, IM_REGION_SUPERSET); 266 if (area == NULL) 267 return 1; 268 269 while (area) { 270 iounmap((void __iomem *) area->addr); 271 area = im_get_area(addr, size, 272 IM_REGION_SUPERSET); 273 } 274 275 return 0; 276} 277 278int __iounmap_explicit(volatile void __iomem *start, unsigned long size) 279{ 280 struct vm_struct *area; 281 unsigned long addr; 282 int rc; 283 284 addr = (unsigned long __force) start & PAGE_MASK; 285 286 /* Verify that the region either exists or is a subset of an existing 287 * region. In the latter case, split the parent region to create 288 * the exact region 289 */ 290 area = im_get_area(addr, size, 291 IM_REGION_EXISTS | IM_REGION_SUBSET); 292 if (area == NULL) { 293 /* Determine whether subset regions exist. If so, unmap */ 294 rc = iounmap_subset_regions(addr, size); 295 if (rc) { 296 printk(KERN_ERR 297 "%s() cannot unmap nonexistent range 0x%lx\n", 298 __FUNCTION__, addr); 299 return 1; 300 } 301 } else { 302 iounmap((void __iomem *) area->addr); 303 } 304 return 0; 305} 306 307EXPORT_SYMBOL(ioremap); 308EXPORT_SYMBOL(ioremap_flags); 309EXPORT_SYMBOL(__ioremap); 310EXPORT_SYMBOL(iounmap); 311EXPORT_SYMBOL(__iounmap); 312 313static DEFINE_SPINLOCK(phb_io_lock); 314 315void __iomem * reserve_phb_iospace(unsigned long size) 316{ 317 void __iomem *virt_addr; 318 319 if (phbs_io_bot >= IMALLOC_BASE) 320 panic("reserve_phb_iospace(): phb io space overflow\n"); 321 322 spin_lock(&phb_io_lock); 323 virt_addr = (void __iomem *) phbs_io_bot; 324 phbs_io_bot += size; 325 spin_unlock(&phb_io_lock); 326 327 return virt_addr; 328} 329