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