arch/ppc64/kernel/pci_iommu.c

   1 /*
   2  * arch/ppc64/kernel/pci_iommu.c
   3  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
   4  *
   5  * Rewrite, cleanup, new allocation schemes:
   6  * Copyright (C) 2004 Olof Johansson, IBM Corporation
   7  *
   8  * Dynamic DMA mapping support, platform-independent parts.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  23  */
  24
  25
  26 #include <linux/config.h>
  27 #include <linux/init.h>
  28 #include <linux/types.h>
  29 #include <linux/slab.h>
  30 #include <linux/mm.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/string.h>
  33 #include <linux/pci.h>
  34 #include <linux/dma-mapping.h>
  35 #include <asm/io.h>
  36 #include <asm/prom.h>
  37 #include <asm/iommu.h>
  38 #include <asm/pci-bridge.h>
  39 #include <asm/machdep.h>
  40 #include "pci.h"
  41
  42 #ifdef CONFIG_PPC_ISERIES
  43 #include <asm/iSeries/iSeries_pci.h>
  44 #endif /* CONFIG_PPC_ISERIES */
  45
  46 static inline struct iommu_table *devnode_table(struct pci_dev *dev)
  47 {
  48         if (!dev)
  49                 dev = ppc64_isabridge_dev;
  50         if (!dev)
  51                 return NULL;
  52
  53 #ifdef CONFIG_PPC_ISERIES
  54         return ISERIES_DEVNODE(dev)->iommu_table;
  55 #endif /* CONFIG_PPC_ISERIES */
  56
  57 #ifdef CONFIG_PPC_MULTIPLATFORM
  58         return PCI_GET_DN(dev)->iommu_table;
  59 #endif /* CONFIG_PPC_MULTIPLATFORM */
  60 }
  61
  62
  63 /* Allocates a contiguous real buffer and creates mappings over it.
  64  * Returns the virtual address of the buffer and sets dma_handle
  65  * to the dma address (mapping) of the first page.
  66  */
  67 static void *pci_iommu_alloc_consistent(struct pci_dev *hwdev, size_t size,
  68                            dma_addr_t *dma_handle)
  69 {
  70         return iommu_alloc_consistent(devnode_table(hwdev), size, dma_handle);
  71 }
  72
  73 static void pci_iommu_free_consistent(struct pci_dev *hwdev, size_t size,
  74                          void *vaddr, dma_addr_t dma_handle)
  75 {
  76         iommu_free_consistent(devnode_table(hwdev), size, vaddr, dma_handle);
  77 }
  78
  79 /* Creates TCEs for a user provided buffer.  The user buffer must be
  80  * contiguous real kernel storage (not vmalloc).  The address of the buffer
  81  * passed here is the kernel (virtual) address of the buffer.  The buffer
  82  * need not be page aligned, the dma_addr_t returned will point to the same
  83  * byte within the page as vaddr.
  84  */
  85 static dma_addr_t pci_iommu_map_single(struct pci_dev *hwdev, void *vaddr,
  86                 size_t size, enum dma_data_direction direction)
  87 {
  88         return iommu_map_single(devnode_table(hwdev), vaddr, size, direction);
  89 }
  90
  91
  92 static void pci_iommu_unmap_single(struct pci_dev *hwdev, dma_addr_t dma_handle,
  93                 size_t size, enum dma_data_direction direction)
  94 {
  95         iommu_unmap_single(devnode_table(hwdev), dma_handle, size, direction);
  96 }
  97
  98
  99 static int pci_iommu_map_sg(struct pci_dev *pdev, struct scatterlist *sglist,
 100                 int nelems, enum dma_data_direction direction)
 101 {
 102         return iommu_map_sg(&pdev->dev, devnode_table(pdev), sglist,
 103                         nelems, direction);
 104 }
 105
 106 static void pci_iommu_unmap_sg(struct pci_dev *pdev, struct scatterlist *sglist,
 107                 int nelems, enum dma_data_direction direction)
 108 {
 109         iommu_unmap_sg(devnode_table(pdev), sglist, nelems, direction);
 110 }
 111
 112 /* We support DMA to/from any memory page via the iommu */
 113 static int pci_iommu_dma_supported(struct pci_dev *pdev, u64 mask)
 114 {
 115         return 1;
 116 }
 117
 118 void pci_iommu_init(void)
 119 {
 120         pci_dma_ops.pci_alloc_consistent = pci_iommu_alloc_consistent;
 121         pci_dma_ops.pci_free_consistent = pci_iommu_free_consistent;
 122         pci_dma_ops.pci_map_single = pci_iommu_map_single;
 123         pci_dma_ops.pci_unmap_single = pci_iommu_unmap_single;
 124         pci_dma_ops.pci_map_sg = pci_iommu_map_sg;
 125         pci_dma_ops.pci_unmap_sg = pci_iommu_unmap_sg;
 126         pci_dma_ops.pci_dma_supported = pci_iommu_dma_supported;
 127 }