release/src-rt-6.x.4708/linux/linux-2.6.36/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 #include <linux/slab.h>
  33
  34 #include <asm/iommu.h>
  35 #include <asm/vio.h>
  36 #include <asm/tce.h>
  37 #include <asm/machdep.h>
  38 #include <asm/abs_addr.h>
  39 #include <asm/prom.h>
  40 #include <asm/pci-bridge.h>
  41 #include <asm/iseries/hv_call_xm.h>
  42 #include <asm/iseries/hv_call_event.h>
  43 #include <asm/iseries/iommu.h>
  44
  45 static int tce_build_iSeries(struct iommu_table *tbl, long index, long npages,
  46                 unsigned long uaddr, enum dma_data_direction direction,
  47                 struct dma_attrs *attrs)
  48 {
  49         u64 rc;
  50         u64 tce, rpn;
  51
  52         while (npages--) {
  53                 rpn = virt_to_abs(uaddr) >> TCE_SHIFT;
  54                 tce = (rpn & TCE_RPN_MASK) << TCE_RPN_SHIFT;
  55
  56                 if (tbl->it_type == TCE_VB) {
  57                         /* Virtual Bus */
  58                         tce |= TCE_VALID|TCE_ALLIO;
  59                         if (direction != DMA_TO_DEVICE)
  60                                 tce |= TCE_VB_WRITE;
  61                 } else {
  62                         /* PCI Bus */
  63                         tce |= TCE_PCI_READ; /* Read allowed */
  64                         if (direction != DMA_TO_DEVICE)
  65                                 tce |= TCE_PCI_WRITE;
  66                 }
  67
  68                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, tce);
  69                 if (rc)
  70                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%llx\n",
  71                                         rc);
  72                 index++;
  73                 uaddr += TCE_PAGE_SIZE;
  74         }
  75         return 0;
  76 }
  77
  78 static void tce_free_iSeries(struct iommu_table *tbl, long index, long npages)
  79 {
  80         u64 rc;
  81
  82         while (npages--) {
  83                 rc = HvCallXm_setTce((u64)tbl->it_index, (u64)index, 0);
  84                 if (rc)
  85                         panic("PCI_DMA: HvCallXm_setTce failed, Rc: 0x%llx\n",
  86                                         rc);
  87                 index++;
  88         }
  89 }
  90
  91 /*
  92  * Structure passed to HvCallXm_getTceTableParms
  93  */
  94 struct iommu_table_cb {
  95         unsigned long   itc_busno;      /* Bus number for this tce table */
  96         unsigned long   itc_start;      /* Will be NULL for secondary */
  97         unsigned long   itc_totalsize;  /* Size (in pages) of whole table */
  98         unsigned long   itc_offset;     /* Index into real tce table of the
  99                                            start of our section */
 100         unsigned long   itc_size;       /* Size (in pages) of our section */
 101         unsigned long   itc_index;      /* Index of this tce table */
 102         unsigned short  itc_maxtables;  /* Max num of tables for partition */
 103         unsigned char   itc_virtbus;    /* Flag to indicate virtual bus */
 104         unsigned char   itc_slotno;     /* IOA Tce Slot Index */
 105         unsigned char   itc_rsvd[4];
 106 };
 107
 108 /*
 109  * Call Hv with the architected data structure to get TCE table info.
 110  * info. Put the returned data into the Linux representation of the
 111  * TCE table data.
 112  * The Hardware Tce table comes in three flavors.
 113  * 1. TCE table shared between Buses.
 114  * 2. TCE table per Bus.
 115  * 3. TCE Table per IOA.
 116  */
 117 void iommu_table_getparms_iSeries(unsigned long busno,
 118                                   unsigned char slotno,
 119                                   unsigned char virtbus,
 120                                   struct iommu_table* tbl)
 121 {
 122         struct iommu_table_cb *parms;
 123
 124         parms = kzalloc(sizeof(*parms), GFP_KERNEL);
 125         if (parms == NULL)
 126                 panic("PCI_DMA: TCE Table Allocation failed.");
 127
 128         parms->itc_busno = busno;
 129         parms->itc_slotno = slotno;
 130         parms->itc_virtbus = virtbus;
 131
 132         HvCallXm_getTceTableParms(iseries_hv_addr(parms));
 133
 134         if (parms->itc_size == 0)
 135                 panic("PCI_DMA: parms->size is zero, parms is 0x%p", parms);
 136
 137         /* itc_size is in pages worth of table, it_size is in # of entries */
 138         tbl->it_size = (parms->itc_size * TCE_PAGE_SIZE) / TCE_ENTRY_SIZE;
 139         tbl->it_busno = parms->itc_busno;
 140         tbl->it_offset = parms->itc_offset;
 141         tbl->it_index = parms->itc_index;
 142         tbl->it_blocksize = 1;
 143         tbl->it_type = virtbus ? TCE_VB : TCE_PCI;
 144
 145         kfree(parms);
 146 }
 147
 148
 149 #ifdef CONFIG_PCI
 150 /*
 151  * This function compares the known tables to find an iommu_table
 152  * that has already been built for hardware TCEs.
 153  */
 154 static struct iommu_table *iommu_table_find(struct iommu_table * tbl)
 155 {
 156         struct device_node *node;
 157
 158         for (node = NULL; (node = of_find_all_nodes(node)); ) {
 159                 struct pci_dn *pdn = PCI_DN(node);
 160                 struct iommu_table *it;
 161
 162                 if (pdn == NULL)
 163                         continue;
 164                 it = pdn->iommu_table;
 165                 if ((it != NULL) &&
 166                     (it->it_type == TCE_PCI) &&
 167                     (it->it_offset == tbl->it_offset) &&
 168                     (it->it_index == tbl->it_index) &&
 169                     (it->it_size == tbl->it_size)) {
 170                         of_node_put(node);
 171                         return it;
 172                 }
 173         }
 174         return NULL;
 175 }
 176
 177
 178 static void pci_dma_dev_setup_iseries(struct pci_dev *pdev)
 179 {
 180         struct iommu_table *tbl;
 181         struct device_node *dn = pci_device_to_OF_node(pdev);
 182         struct pci_dn *pdn = PCI_DN(dn);
 183         const u32 *lsn = of_get_property(dn, "linux,logical-slot-number", NULL);
 184
 185         BUG_ON(lsn == NULL);
 186
 187         tbl = kzalloc(sizeof(struct iommu_table), GFP_KERNEL);
 188
 189         iommu_table_getparms_iSeries(pdn->busno, *lsn, 0, tbl);
 190
 191         /* Look for existing tce table */
 192         pdn->iommu_table = iommu_table_find(tbl);
 193         if (pdn->iommu_table == NULL)
 194                 pdn->iommu_table = iommu_init_table(tbl, -1);
 195         else
 196                 kfree(tbl);
 197         set_iommu_table_base(&pdev->dev, pdn->iommu_table);
 198 }
 199 #else
 200 #define pci_dma_dev_setup_iseries       NULL
 201 #endif
 202
 203 static struct iommu_table veth_iommu_table;
 204 static struct iommu_table vio_iommu_table;
 205
 206 void *iseries_hv_alloc(size_t size, dma_addr_t *dma_handle, gfp_t flag)
 207 {
 208         return iommu_alloc_coherent(NULL, &vio_iommu_table, size, dma_handle,
 209                                 DMA_BIT_MASK(32), flag, -1);
 210 }
 211 EXPORT_SYMBOL_GPL(iseries_hv_alloc);
 212
 213 void iseries_hv_free(size_t size, void *vaddr, dma_addr_t dma_handle)
 214 {
 215         iommu_free_coherent(&vio_iommu_table, size, vaddr, dma_handle);
 216 }
 217 EXPORT_SYMBOL_GPL(iseries_hv_free);
 218
 219 dma_addr_t iseries_hv_map(void *vaddr, size_t size,
 220                         enum dma_data_direction direction)
 221 {
 222         return iommu_map_page(NULL, &vio_iommu_table, virt_to_page(vaddr),
 223                               (unsigned long)vaddr % PAGE_SIZE, size,
 224                               DMA_BIT_MASK(32), direction, NULL);
 225 }
 226
 227 void iseries_hv_unmap(dma_addr_t dma_handle, size_t size,
 228                         enum dma_data_direction direction)
 229 {
 230         iommu_unmap_page(&vio_iommu_table, dma_handle, size, direction, NULL);
 231 }
 232
 233 void __init iommu_vio_init(void)
 234 {
 235         iommu_table_getparms_iSeries(255, 0, 0xff, &veth_iommu_table);
 236         veth_iommu_table.it_size /= 2;
 237         vio_iommu_table = veth_iommu_table;
 238         vio_iommu_table.it_offset += veth_iommu_table.it_size;
 239
 240         if (!iommu_init_table(&veth_iommu_table, -1))
 241                 printk("Virtual Bus VETH TCE table failed.\n");
 242         if (!iommu_init_table(&vio_iommu_table, -1))
 243                 printk("Virtual Bus VIO TCE table failed.\n");
 244 }
 245
 246 struct iommu_table *vio_build_iommu_table_iseries(struct vio_dev *dev)
 247 {
 248         if (strcmp(dev->type, "network") == 0)
 249                 return &veth_iommu_table;
 250         return &vio_iommu_table;
 251 }
 252
 253 void iommu_init_early_iSeries(void)
 254 {
 255         ppc_md.tce_build = tce_build_iSeries;
 256         ppc_md.tce_free  = tce_free_iSeries;
 257
 258         ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_iseries;
 259         set_pci_dma_ops(&dma_iommu_ops);
 260 }