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 int tce_build_iSeries(struct iommu_table *tbl, long index, long npages,
  45                 unsigned long uaddr, enum dma_data_direction direction,
  46                 struct dma_attrs *attrs)
  47 {
  48         u64 rc;
  49         u64 tce, rpn;
  50
  51         while (npages--) {
  52                 rpn = virt_to_abs(uaddr) >> TCE_SHIFT;
  53                 tce = (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT;
  54
  55                 if (tbl->it_type == TCE_VB) {
  56                         /* Virtual Bus */
  57                         tce |= TCE_VALID|TCE_ALLIO;
  58                         if (direction != DMA_TO_DEVICE)
  59                                 tce |= TCE_VB_WRITE;
  60                 } else {
  61                         /* PCI Bus */
  62                         tce |= TCE_PCI_READ; /* Read allowed */
  63                         if (direction != DMA_TO_DEVICE)
  64                                 tce |= TCE_PCI_WRITE;
  65                 }
  66
  67                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, tce);
  68                 if (rc)
  69                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%llx\n",
  70                                         rc);
  71                 index++;
  72                 uaddr += TCE_PAGE_SIZE;
  73         }
  74         return 0;
  75 }
  76
  77 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  78 {
  79         u64 rc;
  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%llx\n",
  85                                         rc);
  86                 index++;
  87         }
  88 }
  89
  90 /*
  91  * Structure passed to HvCallXm_getTceTableParms
  92  */
  93 struct iommu_table_cb {
  94         unsigned long   itc_busno;      /* Bus number for this tce table */
  95         unsigned long   itc_start;      /* Will be NULL for secondary */
  96         unsigned long   itc_totalsize;  /* Size (in pages) of whole table */
  97         unsigned long   itc_offset;     /* Index into real tce table of the
  98                                            start of our section */
  99         unsigned long   itc_size;       /* Size (in pages) of our section */
 100         unsigned long   itc_index;      /* Index of this tce table */
 101         unsigned short  itc_maxtables;  /* Max num of tables for partition */
 102         unsigned char   itc_virtbus;    /* Flag to indicate virtual bus */
 103         unsigned char   itc_slotno;     /* IOA Tce Slot Index */
 104         unsigned char   itc_rsvd[4];
 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 void iommu_table_getparms_iSeries(unsigned long busno,
 117                                   unsigned char slotno,
 118                                   unsigned char virtbus,
 119                                   struct iommu_table* tbl)
 120 {
 121         struct iommu_table_cb *parms;
 122
 123         parms = kzalloc(sizeof(*parms), GFP_KERNEL);
 124         if (parms == NULL)
 125                 panic("PCI_DMA: TCE Table Allocation failed.");
 126
 127         parms->itc_busno = busno;
 128         parms->itc_slotno = slotno;
 129         parms->itc_virtbus = virtbus;
 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 * TCE_PAGE_SIZE) / TCE_ENTRY_SIZE;
 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 = virtbus ? TCE_VB : TCE_PCI;
 143
 144         kfree(parms);
 145 }
 146
 147
 148 #ifdef CONFIG_PCI
 149 /*
 150  * This function compares the known tables to find an iommu_table
 151  * that has already been built for hardware TCEs.
 152  */
 153 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
 154 {
 155         struct device_node *node;
 156
 157         for (node = NULL; (node = of_find_all_nodes(node)); ) {
 158                 struct pci_dn *pdn = PCI_DN(node);
 159                 struct iommu_table *it;
 160
 161                 if (pdn == NULL)
 162                         continue;
 163                 it = pdn->iommu_table;
 164                 if ((it != NULL) &&
 165                     (it->it_type == TCE_PCI) &&
 166                     (it->it_offset == tbl->it_offset) &&
 167                     (it->it_index == tbl->it_index) &&
 168                     (it->it_size == tbl->it_size)) {
 169                         of_node_put(node);
 170                         return it;
 171                 }
 172         }
 173         return NULL;
 174 }
 175
 176
 177 static void pci_dma_dev_setup_iseries(struct pci_dev *pdev)
 178 {
 179         struct iommu_table *tbl;
 180         struct device_node *dn = pci_device_to_OF_node(pdev);
 181         struct pci_dn *pdn = PCI_DN(dn);
 182         const u32 *lsn = of_get_property(dn, "linux,logical-slot-number", NULL);
 183
 184         BUG_ON(lsn == NULL);
 185
 186         tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL);
 187
 188         iommu_table_getparms_iSeries(pdn->busno, *lsn, 0, tbl);
 189
 190         /* Look for existing tce table */
 191         pdn->iommu_table = iommu_table_find(tbl);
 192         if (pdn->iommu_table == NULL)
 193                 pdn->iommu_table = iommu_init_table(tbl, -1);
 194         else
 195                 kfree(tbl);
 196         set_iommu_table_base(&pdev->dev, pdn->iommu_table);
 197 }
 198 #else
 199 #define pci_dma_dev_setup_iseries       NULL
 200 #endif
 201
 202 static struct iommu_table veth_iommu_table;
 203 static struct iommu_table vio_iommu_table;
 204
 205 void *iseries_hv_alloc(size_t size, dma_addr_t *dma_handle, gfp_t flag)
 206 {
 207         return iommu_alloc_coherent(NULL, &vio_iommu_table, size, dma_handle,
 208                                 DMA_BIT_MASK(32), flag, -1);
 209 }
 210 EXPORT_SYMBOL_GPL(iseries_hv_alloc);
 211
 212 void iseries_hv_free(size_t size, void *vaddr, dma_addr_t dma_handle)
 213 {
 214         iommu_free_coherent(&vio_iommu_table, size, vaddr, dma_handle);
 215 }
 216 EXPORT_SYMBOL_GPL(iseries_hv_free);
 217
 218 dma_addr_t iseries_hv_map(void *vaddr, size_t size,
 219                         enum dma_data_direction direction)
 220 {
 221         return iommu_map_page(NULL, &vio_iommu_table, virt_to_page(vaddr),
 222                               (unsigned long)vaddr % PAGE_SIZE, size,
 223                               DMA_BIT_MASK(32), direction, NULL);
 224 }
 225
 226 void iseries_hv_unmap(dma_addr_t dma_handle, size_t size,
 227                         enum dma_data_direction direction)
 228 {
 229         iommu_unmap_page(&vio_iommu_table, dma_handle, size, direction, NULL);
 230 }
 231
 232 void __init iommu_vio_init(void)
 233 {
 234         iommu_table_getparms_iSeries(255, 0, 0xff, &veth_iommu_table);
 235         veth_iommu_table.it_size /= 2;
 236         vio_iommu_table = veth_iommu_table;
 237         vio_iommu_table.it_offset += veth_iommu_table.it_size;
 238
 239         if (!iommu_init_table(&veth_iommu_table, -1))
 240                 printk("Virtual Bus VETH TCE table failed.\n");
 241         if (!iommu_init_table(&vio_iommu_table, -1))
 242                 printk("Virtual Bus VIO TCE table failed.\n");
 243 }
 244
 245 struct iommu_table *vio_build_iommu_table_iseries(struct vio_dev *dev)
 246 {
 247         if (strcmp(dev->type, "network") == 0)
 248                 return &veth_iommu_table;
 249         return &vio_iommu_table;
 250 }
 251
 252 void iommu_init_early_iSeries(void)
 253 {
 254         ppc_md.tce_build = tce_build_iSeries;
 255         ppc_md.tce_free  = tce_free_iSeries;
 256
 257         ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_iseries;
 258         set_pci_dma_ops(&dma_iommu_ops);
 259 }