1/* 2 * This file manages the translation entries for the IBM Calgary IOMMU. 3 * 4 * Derived from arch/powerpc/platforms/pseries/iommu.c 5 * 6 * Copyright (C) IBM Corporation, 2006 7 * 8 * Author: Jon Mason <jdmason@us.ibm.com> 9 * Author: Muli Ben-Yehuda <muli@il.ibm.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 24 */ 25 26#include <linux/types.h> 27#include <linux/slab.h> 28#include <linux/mm.h> 29#include <linux/spinlock.h> 30#include <linux/string.h> 31#include <linux/pci.h> 32#include <linux/dma-mapping.h> 33#include <linux/bootmem.h> 34#include <asm/tce.h> 35#include <asm/calgary.h> 36#include <asm/proto.h> 37 38/* flush a tce at 'tceaddr' to main memory */ 39static inline void flush_tce(void* tceaddr) 40{ 41 /* a single tce can't cross a cache line */ 42 if (cpu_has_clflush) 43 asm volatile("clflush (%0)" :: "r" (tceaddr)); 44 else 45 asm volatile("wbinvd":::"memory"); 46} 47 48void tce_build(struct iommu_table *tbl, unsigned long index, 49 unsigned int npages, unsigned long uaddr, int direction) 50{ 51 u64* tp; 52 u64 t; 53 u64 rpn; 54 55 t = (1 << TCE_READ_SHIFT); 56 if (direction != DMA_TO_DEVICE) 57 t |= (1 << TCE_WRITE_SHIFT); 58 59 tp = ((u64*)tbl->it_base) + index; 60 61 while (npages--) { 62 rpn = (virt_to_bus((void*)uaddr)) >> PAGE_SHIFT; 63 t &= ~TCE_RPN_MASK; 64 t |= (rpn << TCE_RPN_SHIFT); 65 66 *tp = cpu_to_be64(t); 67 flush_tce(tp); 68 69 uaddr += PAGE_SIZE; 70 tp++; 71 } 72} 73 74void tce_free(struct iommu_table *tbl, long index, unsigned int npages) 75{ 76 u64* tp; 77 78 tp = ((u64*)tbl->it_base) + index; 79 80 while (npages--) { 81 *tp = cpu_to_be64(0); 82 flush_tce(tp); 83 tp++; 84 } 85} 86 87static inline unsigned int table_size_to_number_of_entries(unsigned char size) 88{ 89 /* 90 * size is the order of the table, 0-7 91 * smallest table is 8K entries, so shift result by 13 to 92 * multiply by 8K 93 */ 94 return (1 << size) << 13; 95} 96 97static int tce_table_setparms(struct pci_dev *dev, struct iommu_table *tbl) 98{ 99 unsigned int bitmapsz; 100 unsigned long bmppages; 101 int ret; 102 103 tbl->it_busno = dev->bus->number; 104 105 /* set the tce table size - measured in entries */ 106 tbl->it_size = table_size_to_number_of_entries(specified_table_size); 107 108 /* 109 * number of bytes needed for the bitmap size in number of 110 * entries; we need one bit per entry 111 */ 112 bitmapsz = tbl->it_size / BITS_PER_BYTE; 113 bmppages = __get_free_pages(GFP_KERNEL, get_order(bitmapsz)); 114 if (!bmppages) { 115 printk(KERN_ERR "Calgary: cannot allocate bitmap\n"); 116 ret = -ENOMEM; 117 goto done; 118 } 119 120 tbl->it_map = (unsigned long*)bmppages; 121 122 memset(tbl->it_map, 0, bitmapsz); 123 124 tbl->it_hint = 0; 125 126 spin_lock_init(&tbl->it_lock); 127 128 return 0; 129 130done: 131 return ret; 132} 133 134int build_tce_table(struct pci_dev *dev, void __iomem *bbar) 135{ 136 struct iommu_table *tbl; 137 int ret; 138 139 if (dev->sysdata) { 140 printk(KERN_ERR "Calgary: dev %p has sysdata %p\n", 141 dev, dev->sysdata); 142 BUG(); 143 } 144 145 tbl = kzalloc(sizeof(struct iommu_table), GFP_KERNEL); 146 if (!tbl) { 147 printk(KERN_ERR "Calgary: error allocating iommu_table\n"); 148 ret = -ENOMEM; 149 goto done; 150 } 151 152 ret = tce_table_setparms(dev, tbl); 153 if (ret) 154 goto free_tbl; 155 156 tbl->bbar = bbar; 157 158 /* 159 * NUMA is already using the bus's sysdata pointer, so we use 160 * the bus's pci_dev's sysdata instead. 161 */ 162 dev->sysdata = tbl; 163 164 return 0; 165 166free_tbl: 167 kfree(tbl); 168done: 169 return ret; 170} 171 172void* alloc_tce_table(void) 173{ 174 unsigned int size; 175 176 size = table_size_to_number_of_entries(specified_table_size); 177 size *= TCE_ENTRY_SIZE; 178 179 return __alloc_bootmem_low(size, size, 0); 180} 181 182void free_tce_table(void *tbl) 183{ 184 unsigned int size; 185 186 if (!tbl) 187 return; 188 189 size = table_size_to_number_of_entries(specified_table_size); 190 size *= TCE_ENTRY_SIZE; 191 192 free_bootmem(__pa(tbl), size); 193} 194