arch/ppc64/kernel/iSeries_iommu.c

   1 /*
   2  * arch/ppc64/kernel/iSeries_iommu.c
   3  *
   4  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
   5  *
   6  * Rewrite, cleanup:
   7  *
   8  * Copyright (C) 2004 Olof Johansson <olof@austin.ibm.com>, IBM Corporation
   9  *
  10  * Dynamic DMA mapping support, iSeries-specific parts.
  11  *
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  26  */
  27
  28 #include <linux/types.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/list.h>
  31
  32 #include <asm/iommu.h>
  33 #include <asm/machdep.h>
  34 #include <asm/iSeries/HvCallXm.h>
  35 #include <asm/iSeries/iSeries_pci.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
  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 iSeries_Device_Node *dp;
  94
  95         list_for_each_entry(dp, &iSeries_Global_Device_List, Device_List) {
  96                 if ((dp->iommu_table != NULL) &&
  97                     (dp->iommu_table->it_type == TCE_PCI) &&
  98                     (dp->iommu_table->it_offset == tbl->it_offset) &&
  99                     (dp->iommu_table->it_index == tbl->it_index) &&
 100                     (dp->iommu_table->it_size == tbl->it_size))
 101                         return dp->iommu_table;
 102         }
 103         return NULL;
 104 }
 105
 106 /*
 107  * Call Hv with the architected data structure to get TCE table info.
 108  * info. Put the returned data into the Linux representation of the
 109  * TCE table data.
 110  * The Hardware Tce table comes in three flavors.
 111  * 1. TCE table shared between Buses.
 112  * 2. TCE table per Bus.
 113  * 3. TCE Table per IOA.
 114  */
 115 static void iommu_table_getparms(struct iSeries_Device_Node* dn,
 116                                  struct iommu_table* tbl)
 117 {
 118         struct iommu_table_cb *parms;
 119
 120         parms = kmalloc(sizeof(*parms), GFP_KERNEL);
 121         if (parms == NULL)
 122                 panic("PCI_DMA: TCE Table Allocation failed.");
 123
 124         memset(parms, 0, sizeof(*parms));
 125
 126         parms->itc_busno = ISERIES_BUS(dn);
 127         parms->itc_slotno = dn->LogicalSlot;
 128         parms->itc_virtbus = 0;
 129
 130         HvCallXm_getTceTableParms(ISERIES_HV_ADDR(parms));
 131
 132         if (parms->itc_size == 0)
 133                 panic("PCI_DMA: parms->size is zero, parms is 0x%p", parms);
 134
 135         /* itc_size is in pages worth of table, it_size is in # of entries */
 136         tbl->it_size = (parms->itc_size * PAGE_SIZE) / sizeof(union tce_entry);
 137         tbl->it_busno = parms->itc_busno;
 138         tbl->it_offset = parms->itc_offset;
 139         tbl->it_index = parms->itc_index;
 140         tbl->it_blocksize = 1;
 141         tbl->it_type = TCE_PCI;
 142
 143         kfree(parms);
 144 }
 145
 146
 147 void iommu_devnode_init_iSeries(struct iSeries_Device_Node *dn)
 148 {
 149         struct iommu_table *tbl;
 150
 151         tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 152
 153         iommu_table_getparms(dn, tbl);
 154
 155         /* Look for existing tce table */
 156         dn->iommu_table = iommu_table_find(tbl);
 157         if (dn->iommu_table == NULL)
 158                 dn->iommu_table = iommu_init_table(tbl);
 159         else
 160                 kfree(tbl);
 161 }
 162
 163 static void iommu_dev_setup_iSeries(struct pci_dev *dev) { }
 164 static void iommu_bus_setup_iSeries(struct pci_bus *bus) { }
 165
 166 void iommu_init_early_iSeries(void)
 167 {
 168         ppc_md.tce_build = tce_build_iSeries;
 169         ppc_md.tce_free  = tce_free_iSeries;
 170
 171         ppc_md.iommu_dev_setup = iommu_dev_setup_iSeries;
 172         ppc_md.iommu_bus_setup = iommu_bus_setup_iSeries;
 173
 174         pci_iommu_init();
 175 }