arch/powerpc/platforms/iseries/iommu.c

   1 /*
   2  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
   3  *
   4  * Rewrite, cleanup:
   5  *
   6  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
   7  *
   8  * Dynamic DMA mapping support, iSeries-specific parts.
   9  *
  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/dma-mapping.h>
  28 #include <linux/list.h>
  29
  30 #include <asm/iommu.h>
  31 #include <asm/tce.h>
  32 #include <asm/machdep.h>
  33 #include <asm/abs_addr.h>
  34 #include <asm/pci-bridge.h>
  35 #include <asm/iseries/hv_call_xm.h>
  36
  37 #include "iommu.h"
  38
  39 extern struct list_head iSeries_Global_Device_List;
  40
  41
  42 static void tce_build_iSeries(struct iommu_table *tbl, long index, long npages,
  43                 unsigned long uaddr, enum dma_data_direction direction)
  44 {
  45         u64 rc;
  46         union tce_entry tce;
  47
  48         index <<= TCE_PAGE_FACTOR;
  49         npages <<= TCE_PAGE_FACTOR;
  50
  51         while (npages--) {
  52                 tce.te_word = 0;
  53                 tce.te_bits.tb_rpn = virt_to_abs(uaddr) >> TCE_SHIFT;
  54
  55                 if (tbl->it_type == TCE_VB) {
  56                         /* Virtual Bus */
  57                         tce.te_bits.tb_valid = 1;
  58                         tce.te_bits.tb_allio = 1;
  59                         if (direction != DMA_TO_DEVICE)
  60                                 tce.te_bits.tb_rdwr = 1;
  61                 } else {
  62                         /* PCI Bus */
  63                         tce.te_bits.tb_rdwr = 1; /* Read allowed */
  64                         if (direction != DMA_TO_DEVICE)
  65                                 tce.te_bits.tb_pciwr = 1;
  66                 }
  67
  68                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index,
  69                                 tce.te_word);
  70                 if (rc)
  71                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  72                                         rc);
  73                 index++;
  74                 uaddr += TCE_PAGE_SIZE;
  75         }
  76 }
  77
  78 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  79 {
  80         u64 rc;
  81
  82         npages <<= TCE_PAGE_FACTOR;
  83         index <<= TCE_PAGE_FACTOR;
  84
  85         while (npages--) {
  86                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, 0);
  87                 if (rc)
  88                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  89                                         rc);
  90                 index++;
  91         }
  92 }
  93
  94 /*
  95  * Call Hv with the architected data structure to get TCE table info.
  96  * info. Put the returned data into the Linux representation of the
  97  * TCE table data.
  98  * The Hardware Tce table comes in three flavors.
  99  * 1. TCE table shared between Buses.
 100  * 2. TCE table per Bus.
 101  * 3. TCE Table per IOA.
 102  */
 103 void iommu_table_getparms_iSeries(unsigned long busno,
 104                                   unsigned char slotno,
 105                                   unsigned char virtbus,
 106                                   struct iommu_table* tbl)
 107 {
 108         struct iommu_table_cb *parms;
 109
 110         parms = kmalloc(sizeof(*parms), GFP_KERNEL);
 111         if (parms == NULL)
 112                 panic("PCI_DMA: TCE Table Allocation failed.");
 113
 114         memset(parms, 0, sizeof(*parms));
 115
 116         parms->itc_busno = busno;
 117         parms->itc_slotno = slotno;
 118         parms->itc_virtbus = virtbus;
 119
 120         HvCallXm_getTceTableParms(iseries_hv_addr(parms));
 121
 122         if (parms->itc_size == 0)
 123                 panic("PCI_DMA: parms->size is zero, parms is 0x%p", parms);
 124
 125         /* itc_size is in pages worth of table, it_size is in # of entries */
 126         tbl->it_size = ((parms->itc_size * TCE_PAGE_SIZE) /
 127                         sizeof(union tce_entry)) >> TCE_PAGE_FACTOR;
 128         tbl->it_busno = parms->itc_busno;
 129         tbl->it_offset = parms->itc_offset >> TCE_PAGE_FACTOR;
 130         tbl->it_index = parms->itc_index;
 131         tbl->it_blocksize = 1;
 132         tbl->it_type = virtbus ? TCE_VB : TCE_PCI;
 133
 134         kfree(parms);
 135 }
 136
 137
 138 #ifdef CONFIG_PCI
 139 /*
 140  * This function compares the known tables to find an iommu_table
 141  * that has already been built for hardware TCEs.
 142  */
 143 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
 144 {
 145         struct pci_dn *pdn;
 146
 147         list_for_each_entry(pdn, &iSeries_Global_Device_List, Device_List) {
 148                 struct iommu_table *it = pdn->iommu_table;
 149                 if ((it != NULL) &&
 150                     (it->it_type == TCE_PCI) &&
 151                     (it->it_offset == tbl->it_offset) &&
 152                     (it->it_index == tbl->it_index) &&
 153                     (it->it_size == tbl->it_size))
 154                         return it;
 155         }
 156         return NULL;
 157 }
 158
 159
 160 void iommu_devnode_init_iSeries(struct device_node *dn)
 161 {
 162         struct iommu_table *tbl;
 163         struct pci_dn *pdn = PCI_DN(dn);
 164
 165         tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 166
 167         iommu_table_getparms_iSeries(pdn->busno, pdn->LogicalSlot, 0, tbl);
 168
 169         /* Look for existing tce table */
 170         pdn->iommu_table = iommu_table_find(tbl);
 171         if (pdn->iommu_table == NULL)
 172                 pdn->iommu_table = iommu_init_table(tbl);
 173         else
 174                 kfree(tbl);
 175 }
 176 #endif
 177
 178 static void iommu_dev_setup_iSeries(struct pci_dev *dev) { }
 179 static void iommu_bus_setup_iSeries(struct pci_bus *bus) { }
 180
 181 void iommu_init_early_iSeries(void)
 182 {
 183         ppc_md.tce_build = tce_build_iSeries;
 184         ppc_md.tce_free  = tce_free_iSeries;
 185
 186         ppc_md.iommu_dev_setup = iommu_dev_setup_iSeries;
 187         ppc_md.iommu_bus_setup = iommu_bus_setup_iSeries;
 188
 189         pci_iommu_init();
 190 }