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 #include <linux/pci.h>
  31 #include <linux/module.h>
  32
  33 #include <asm/iommu.h>
  34 #include <asm/vio.h>
  35 #include <asm/tce.h>
  36 #include <asm/machdep.h>
  37 #include <asm/abs_addr.h>
  38 #include <asm/prom.h>
  39 #include <asm/pci-bridge.h>
  40 #include <asm/iseries/hv_call_xm.h>
  41 #include <asm/iseries/hv_call_event.h>
  42 #include <asm/iseries/iommu.h>
  43
  44 static void tce_build_iSeries(struct iommu_table *tbl, long index, long npages,
  45                 unsigned long uaddr, enum dma_data_direction direction)
  46 {
  47         u64 rc;
  48         u64 tce, rpn;
  49
  50         while (npages--) {
  51                 rpn = virt_to_abs(uaddr) >> TCE_SHIFT;
  52                 tce = (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT;
  53
  54                 if (tbl->it_type == TCE_VB) {
  55                         /* Virtual Bus */
  56                         tce |= TCE_VALID|TCE_ALLIO;
  57                         if (direction != DMA_TO_DEVICE)
  58                                 tce |= TCE_VB_WRITE;
  59                 } else {
  60                         /* PCI Bus */
  61                         tce |= TCE_PCI_READ; /* Read allowed */
  62                         if (direction != DMA_TO_DEVICE)
  63                                 tce |= TCE_PCI_WRITE;
  64                 }
  65
  66                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, tce);
  67                 if (rc)
  68                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  69                                         rc);
  70                 index++;
  71                 uaddr += TCE_PAGE_SIZE;
  72         }
  73 }
  74
  75 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  76 {
  77         u64 rc;
  78
  79         while (npages--) {
  80                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, 0);
  81                 if (rc)
  82                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%lx\n",
  83                                         rc);
  84                 index++;
  85         }
  86 }
  87
  88 /*
  89  * Structure passed to HvCallXm_getTceTableParms
  90  */
  91 struct iommu_table_cb {
  92         unsigned long   itc_busno;      /* Bus number for this tce table */
  93         unsigned long   itc_start;      /* Will be NULL for secondary */
  94         unsigned long   itc_totalsize;  /* Size (in pages) of whole table */
  95         unsigned long   itc_offset;     /* Index into real tce table of the
  96                                            start of our section */
  97         unsigned long   itc_size;       /* Size (in pages) of our section */
  98         unsigned long   itc_index;      /* Index of this tce table */
  99         unsigned short  itc_maxtables;  /* Max num of tables for partition */
 100         unsigned char   itc_virtbus;    /* Flag to indicate virtual bus */
 101         unsigned char   itc_slotno;     /* IOA Tce Slot Index */
 102         unsigned char   itc_rsvd[4];
 103 };
 104
 105 /*
 106  * Call Hv with the architected data structure to get TCE table info.
 107  * info. Put the returned data into the Linux representation of the
 108  * TCE table data.
 109  * The Hardware Tce table comes in three flavors.
 110  * 1. TCE table shared between Buses.
 111  * 2. TCE table per Bus.
 112  * 3. TCE Table per IOA.
 113  */
 114 void iommu_table_getparms_iSeries(unsigned long busno,
 115                                   unsigned char slotno,
 116                                   unsigned char virtbus,
 117                                   struct iommu_table* tbl)
 118 {
 119         struct iommu_table_cb *parms;
 120
 121         parms = kzalloc(sizeof(*parms), GFP_KERNEL);
 122         if (parms == NULL)
 123                 panic("PCI_DMA: TCE Table Allocation failed.");
 124
 125         parms->itc_busno = busno;
 126         parms->itc_slotno = slotno;
 127         parms->itc_virtbus = virtbus;
 128
 129         HvCallXm_getTceTableParms(iseries_hv_addr(parms));
 130
 131         if (parms->itc_size == 0)
 132                 panic("PCI_DMA: parms->size is zero, parms is 0x%p", parms);
 133
 134         /* itc_size is in pages worth of table, it_size is in # of entries */
 135         tbl->it_size = (parms->itc_size * TCE_PAGE_SIZE) / TCE_ENTRY_SIZE;
 136         tbl->it_busno = parms->itc_busno;
 137         tbl->it_offset = parms->itc_offset;
 138         tbl->it_index = parms->itc_index;
 139         tbl->it_blocksize = 1;
 140         tbl->it_type = virtbus ? TCE_VB : TCE_PCI;
 141
 142         kfree(parms);
 143 }
 144
 145
 146 #ifdef CONFIG_PCI
 147 /*
 148  * This function compares the known tables to find an iommu_table
 149  * that has already been built for hardware TCEs.
 150  */
 151 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
 152 {
 153         struct device_node *node;
 154
 155         for (node = NULL; (node = of_find_all_nodes(node)); ) {
 156                 struct pci_dn *pdn = PCI_DN(node);
 157                 struct iommu_table *it;
 158
 159                 if (pdn == NULL)
 160                         continue;
 161                 it = pdn->iommu_table;
 162                 if ((it != NULL) &&
 163                     (it->it_type == TCE_PCI) &&
 164                     (it->it_offset == tbl->it_offset) &&
 165                     (it->it_index == tbl->it_index) &&
 166                     (it->it_size == tbl->it_size)) {
 167                         of_node_put(node);
 168                         return it;
 169                 }
 170         }
 171         return NULL;
 172 }
 173
 174
 175 void iommu_devnode_init_iSeries(struct pci_dev *pdev, struct device_node *dn)
 176 {
 177         struct iommu_table *tbl;
 178         struct pci_dn *pdn = PCI_DN(dn);
 179         const u32 *lsn = of_get_property(dn, "linux,logical-slot-number", NULL);
 180
 181         BUG_ON(lsn == NULL);
 182
 183         tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 184
 185         iommu_table_getparms_iSeries(pdn->busno, *lsn, 0, tbl);
 186
 187         /* Look for existing tce table */
 188         pdn->iommu_table = iommu_table_find(tbl);
 189         if (pdn->iommu_table == NULL)
 190                 pdn->iommu_table = iommu_init_table(tbl, -1);
 191         else
 192                 kfree(tbl);
 193         pdev->dev.archdata.dma_data = pdn->iommu_table;
 194 }
 195 #endif
 196
 197 static struct iommu_table veth_iommu_table;
 198 static struct iommu_table vio_iommu_table;
 199
 200 void *iseries_hv_alloc(size_t size, dma_addr_t *dma_handle, gfp_t flag)
 201 {
 202         return iommu_alloc_coherent(&vio_iommu_table, size, dma_handle,
 203                                 DMA_32BIT_MASK, flag, -1);
 204 }
 205 EXPORT_SYMBOL_GPL(iseries_hv_alloc);
 206
 207 void iseries_hv_free(size_t size, void *vaddr, dma_addr_t dma_handle)
 208 {
 209         iommu_free_coherent(&vio_iommu_table, size, vaddr, dma_handle);
 210 }
 211 EXPORT_SYMBOL_GPL(iseries_hv_free);
 212
 213 dma_addr_t iseries_hv_map(void *vaddr, size_t size,
 214                         enum dma_data_direction direction)
 215 {
 216         return iommu_map_single(&vio_iommu_table, vaddr, size,
 217                                 DMA_32BIT_MASK, direction);
 218 }
 219
 220 void iseries_hv_unmap(dma_addr_t dma_handle, size_t size,
 221                         enum dma_data_direction direction)
 222 {
 223         iommu_unmap_single(&vio_iommu_table, dma_handle, size, direction);
 224 }
 225
 226 void __init iommu_vio_init(void)
 227 {
 228         iommu_table_getparms_iSeries(255, 0, 0xff, &veth_iommu_table);
 229         veth_iommu_table.it_size /= 2;
 230         vio_iommu_table = veth_iommu_table;
 231         vio_iommu_table.it_offset += veth_iommu_table.it_size;
 232
 233         if (!iommu_init_table(&veth_iommu_table, -1))
 234                 printk("Virtual Bus VETH TCE table failed.\n");
 235         if (!iommu_init_table(&vio_iommu_table, -1))
 236                 printk("Virtual Bus VIO TCE table failed.\n");
 237 }
 238
 239 struct iommu_table *vio_build_iommu_table_iseries(struct vio_dev *dev)
 240 {
 241         if (strcmp(dev->type, "network") == 0)
 242                 return &veth_iommu_table;
 243         return &vio_iommu_table;
 244 }
 245
 246 void iommu_init_early_iSeries(void)
 247 {
 248         ppc_md.tce_build = tce_build_iSeries;
 249         ppc_md.tce_free  = tce_free_iSeries;
 250
 251         set_pci_dma_ops(&dma_iommu_ops);
 252 }