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  * Copyright (C) 2006 Olof Johansson <olof@lixom.net>
   8  *
   9  * Dynamic DMA mapping support, iSeries-specific parts.
  10  *
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  25  */
  26
  27 #include <linux/types.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/list.h>
  30
  31 #include <asm/iommu.h>
  32 #include <asm/tce.h>
  33 #include <asm/machdep.h>
  34 #include <asm/abs_addr.h>
  35 #include <asm/prom.h>
  36 #include <asm/pci-bridge.h>
  37 #include <asm/iseries/hv_call_xm.h>
  38 #include <asm/iseries/iommu.h>
  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         u64 tce, rpn;
  45
  46         index <<= TCE_PAGE_FACTOR;
  47         npages <<= TCE_PAGE_FACTOR;
  48
  49         while (npages--) {
  50                 rpn = virt_to_abs(uaddr) >> TCE_SHIFT;
  51                 tce = (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT;
  52
  53                 if (tbl->it_type == TCE_VB) {
  54                         /* Virtual Bus */
  55                         tce |= TCE_VALID|TCE_ALLIO;
  56                         if (direction != DMA_TO_DEVICE)
  57                                 tce |= TCE_VB_WRITE;
  58                 } else {
  59                         /* PCI Bus */
  60                         tce |= TCE_PCI_READ; /* Read allowed */
  61                         if (direction != DMA_TO_DEVICE)
  62                                 tce |= TCE_PCI_WRITE;
  63                 }
  64
  65                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, tce);
  66                 if (rc)
  67                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  68                                         rc);
  69                 index++;
  70                 uaddr += TCE_PAGE_SIZE;
  71         }
  72 }
  73
  74 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  75 {
  76         u64 rc;
  77
  78         npages <<= TCE_PAGE_FACTOR;
  79         index <<= TCE_PAGE_FACTOR;
  80
  81         while (npages--) {
  82                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, 0);
  83                 if (rc)
  84                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  85                                         rc);
  86                 index++;
  87         }
  88 }
  89
  90 /*
  91  * Call Hv with the architected data structure to get TCE table info.
  92  * info. Put the returned data into the Linux representation of the
  93  * TCE table data.
  94  * The Hardware Tce table comes in three flavors.
  95  * 1. TCE table shared between Buses.
  96  * 2. TCE table per Bus.
  97  * 3. TCE Table per IOA.
  98  */
  99 void iommu_table_getparms_iSeries(unsigned long busno,
 100                                   unsigned char slotno,
 101                                   unsigned char virtbus,
 102                                   struct iommu_table* tbl)
 103 {
 104         struct iommu_table_cb *parms;
 105
 106         parms = kmalloc(sizeof(*parms), GFP_KERNEL);
 107         if (parms == NULL)
 108                 panic("PCI_DMA: TCE Table Allocation failed.");
 109
 110         memset(parms, 0, sizeof(*parms));
 111
 112         parms->itc_busno = busno;
 113         parms->itc_slotno = slotno;
 114         parms->itc_virtbus = virtbus;
 115
 116         HvCallXm_getTceTableParms(iseries_hv_addr(parms));
 117
 118         if (parms->itc_size == 0)
 119                 panic("PCI_DMA: parms->size is zero, parms is 0x%p", parms);
 120
 121         /* itc_size is in pages worth of table, it_size is in # of entries */
 122         tbl->it_size = ((parms->itc_size * TCE_PAGE_SIZE) /
 123                         TCE_ENTRY_SIZE) >> TCE_PAGE_FACTOR;
 124         tbl->it_busno = parms->itc_busno;
 125         tbl->it_offset = parms->itc_offset >> TCE_PAGE_FACTOR;
 126         tbl->it_index = parms->itc_index;
 127         tbl->it_blocksize = 1;
 128         tbl->it_type = virtbus ? TCE_VB : TCE_PCI;
 129
 130         kfree(parms);
 131 }
 132
 133
 134 #ifdef CONFIG_PCI
 135 /*
 136  * This function compares the known tables to find an iommu_table
 137  * that has already been built for hardware TCEs.
 138  */
 139 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
 140 {
 141         struct device_node *node;
 142
 143         for (node = NULL; (node = of_find_all_nodes(node)); ) {
 144                 struct pci_dn *pdn = PCI_DN(node);
 145                 struct iommu_table *it;
 146
 147                 if (pdn == NULL)
 148                         continue;
 149                 it = pdn->iommu_table;
 150                 if ((it != NULL) &&
 151                     (it->it_type == TCE_PCI) &&
 152                     (it->it_offset == tbl->it_offset) &&
 153                     (it->it_index == tbl->it_index) &&
 154                     (it->it_size == tbl->it_size))
 155                         return it;
 156         }
 157         return NULL;
 158 }
 159
 160
 161 void iommu_devnode_init_iSeries(struct device_node *dn)
 162 {
 163         struct iommu_table *tbl;
 164         struct pci_dn *pdn = PCI_DN(dn);
 165         u32 *lsn = (u32 *)get_property(dn, "linux,logical-slot-number", NULL);
 166
 167         BUG_ON(lsn == NULL);
 168
 169         tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 170
 171         iommu_table_getparms_iSeries(pdn->busno, *lsn, 0, tbl);
 172
 173         /* Look for existing tce table */
 174         pdn->iommu_table = iommu_table_find(tbl);
 175         if (pdn->iommu_table == NULL)
 176                 pdn->iommu_table = iommu_init_table(tbl, -1);
 177         else
 178                 kfree(tbl);
 179 }
 180 #endif
 181
 182 static void iommu_dev_setup_iSeries(struct pci_dev *dev) { }
 183 static void iommu_bus_setup_iSeries(struct pci_bus *bus) { }
 184
 185 void iommu_init_early_iSeries(void)
 186 {
 187         ppc_md.tce_build = tce_build_iSeries;
 188         ppc_md.tce_free  = tce_free_iSeries;
 189
 190         ppc_md.iommu_dev_setup = iommu_dev_setup_iSeries;
 191         ppc_md.iommu_bus_setup = iommu_bus_setup_iSeries;
 192
 193         pci_iommu_init();
 194 }