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/abs_addr.h>
  34 #include <asm/pci-bridge.h>
  35 #include <asm/iSeries/HvCallXm.h>
  36
  37 extern struct list_head iSeries_Global_Device_List;
  38
  39
  40 static void tce_build_iSeries(struct iommu_table *tbl, long index, long npages,
  41                 unsigned long uaddr, enum dma_data_direction direction)
  42 {
  43         u64 rc;
  44         union tce_entry tce;
  45
  46         while (npages--) {
  47                 tce.te_word = 0;
  48                 tce.te_bits.tb_rpn = virt_to_abs(uaddr) >> PAGE_SHIFT;
  49
  50                 if (tbl->it_type == TCE_VB) {
  51                         /* Virtual Bus */
  52                         tce.te_bits.tb_valid = 1;
  53                         tce.te_bits.tb_allio = 1;
  54                         if (direction != DMA_TO_DEVICE)
  55                                 tce.te_bits.tb_rdwr = 1;
  56                 } else {
  57                         /* PCI Bus */
  58                         tce.te_bits.tb_rdwr = 1; /* Read allowed */
  59                         if (direction != DMA_TO_DEVICE)
  60                                 tce.te_bits.tb_pciwr = 1;
  61                 }
  62
  63                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index,
  64                                 tce.te_word);
  65                 if (rc)
  66                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  67                                         rc);
  68                 index++;
  69                 uaddr += PAGE_SIZE;
  70         }
  71 }
  72
  73 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  74 {
  75         u64 rc;
  76
  77         while (npages--) {
  78                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, 0);
  79                 if (rc)
  80                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  81                                         rc);
  82                 index++;
  83         }
  84 }
  85
  86 #ifdef CONFIG_PCI
  87 /*
  88  * This function compares the known tables to find an iommu_table
  89  * that has already been built for hardware TCEs.
  90  */
  91 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
  92 {
  93         struct pci_dn *pdn;
  94
  95         list_for_each_entry(pdn, &iSeries_Global_Device_List, Device_List) {
  96                 struct iommu_table *it = pdn->iommu_table;
  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 pci_dn *pdn,
 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 = pdn->DsaAddr.Dsa.busNumber;
 128         parms->itc_slotno = pdn->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(pdn, 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 }