drivers/dma/ioat.c

   1 /*
   2  * Intel I/OAT DMA Linux driver
   3  * Copyright(c) 2007 Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * The full GNU General Public License is included in this distribution in
  19  * the file called "COPYING".
  20  *
  21  */
  22
  23 /*
  24  * This driver supports an Intel I/OAT DMA engine, which does asynchronous
  25  * copy operations.
  26  */
  27
  28 #include <linux/init.h>
  29 #include <linux/module.h>
  30 #include <linux/pci.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/dca.h>
  33 #include "ioatdma.h"
  34 #include "ioatdma_registers.h"
  35 #include "ioatdma_hw.h"
  36
  37 MODULE_VERSION(IOAT_DMA_VERSION);
  38 MODULE_LICENSE("GPL");
  39 MODULE_AUTHOR("Intel Corporation");
  40
  41 static struct pci_device_id ioat_pci_tbl[] = {
  42         /* I/OAT v1 platforms */
  43         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
  44         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
  45         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
  46         { PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
  47
  48         /* I/OAT v2 platforms */
  49         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB) },
  50
  51         /* I/OAT v3 platforms */
  52         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG0) },
  53         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG1) },
  54         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG2) },
  55         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG3) },
  56         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG4) },
  57         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG5) },
  58         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG6) },
  59         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG7) },
  60         { 0, }
  61 };
  62
  63 struct ioat_device {
  64         struct pci_dev          *pdev;
  65         void __iomem            *iobase;
  66         struct ioatdma_device   *dma;
  67         struct dca_provider     *dca;
  68 };
  69
  70 static int __devinit ioat_probe(struct pci_dev *pdev,
  71                                 const struct pci_device_id *id);
  72 static void __devexit ioat_remove(struct pci_dev *pdev);
  73
  74 static int ioat_dca_enabled = 1;
  75 module_param(ioat_dca_enabled, int, 0644);
  76 MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)");
  77
  78 static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
  79 {
  80         struct ioat_device *device = pci_get_drvdata(pdev);
  81         u8 version;
  82         int err = 0;
  83
  84         version = readb(iobase + IOAT_VER_OFFSET);
  85         switch (version) {
  86         case IOAT_VER_1_2:
  87                 device->dma = ioat_dma_probe(pdev, iobase);
  88                 if (device->dma && ioat_dca_enabled)
  89                         device->dca = ioat_dca_init(pdev, iobase);
  90                 break;
  91         case IOAT_VER_2_0:
  92                 device->dma = ioat_dma_probe(pdev, iobase);
  93                 if (device->dma && ioat_dca_enabled)
  94                         device->dca = ioat2_dca_init(pdev, iobase);
  95                 break;
  96         case IOAT_VER_3_0:
  97                 device->dma = ioat_dma_probe(pdev, iobase);
  98                 if (device->dma && ioat_dca_enabled)
  99                         device->dca = ioat3_dca_init(pdev, iobase);
 100                 break;
 101         default:
 102                 err = -ENODEV;
 103                 break;
 104         }
 105         if (!device->dma)
 106                 err = -ENODEV;
 107         return err;
 108 }
 109
 110 static void ioat_shutdown_functionality(struct pci_dev *pdev)
 111 {
 112         struct ioat_device *device = pci_get_drvdata(pdev);
 113
 114         dev_err(&pdev->dev, "Removing dma and dca services\n");
 115         if (device->dca) {
 116                 unregister_dca_provider(device->dca);
 117                 free_dca_provider(device->dca);
 118                 device->dca = NULL;
 119         }
 120
 121         if (device->dma) {
 122                 ioat_dma_remove(device->dma);
 123                 device->dma = NULL;
 124         }
 125 }
 126
 127 static struct pci_driver ioat_pci_driver = {
 128         .name           = "ioatdma",
 129         .id_table       = ioat_pci_tbl,
 130         .probe          = ioat_probe,
 131         .shutdown       = ioat_shutdown_functionality,
 132         .remove         = __devexit_p(ioat_remove),
 133 };
 134
 135 static int __devinit ioat_probe(struct pci_dev *pdev,
 136                                 const struct pci_device_id *id)
 137 {
 138         void __iomem *iobase;
 139         struct ioat_device *device;
 140         unsigned long mmio_start, mmio_len;
 141         int err;
 142
 143         err = pci_enable_device(pdev);
 144         if (err)
 145                 goto err_enable_device;
 146
 147         err = pci_request_regions(pdev, ioat_pci_driver.name);
 148         if (err)
 149                 goto err_request_regions;
 150
 151         err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
 152         if (err)
 153                 err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
 154         if (err)
 155                 goto err_set_dma_mask;
 156
 157         err = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
 158         if (err)
 159                 err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
 160         if (err)
 161                 goto err_set_dma_mask;
 162
 163         mmio_start = pci_resource_start(pdev, 0);
 164         mmio_len = pci_resource_len(pdev, 0);
 165         iobase = ioremap(mmio_start, mmio_len);
 166         if (!iobase) {
 167                 err = -ENOMEM;
 168                 goto err_ioremap;
 169         }
 170
 171         device = kzalloc(sizeof(*device), GFP_KERNEL);
 172         if (!device) {
 173                 err = -ENOMEM;
 174                 goto err_kzalloc;
 175         }
 176         device->pdev = pdev;
 177         pci_set_drvdata(pdev, device);
 178         device->iobase = iobase;
 179
 180         pci_set_master(pdev);
 181
 182         err = ioat_setup_functionality(pdev, iobase);
 183         if (err)
 184                 goto err_version;
 185
 186         return 0;
 187
 188 err_version:
 189         kfree(device);
 190 err_kzalloc:
 191         iounmap(iobase);
 192 err_ioremap:
 193 err_set_dma_mask:
 194         pci_release_regions(pdev);
 195         pci_disable_device(pdev);
 196 err_request_regions:
 197 err_enable_device:
 198         return err;
 199 }
 200
 201 /*
 202  * It is unsafe to remove this module: if removed while a requested
 203  * dma is outstanding, esp. from tcp, it is possible to hang while
 204  * waiting for something that will never finish.  However, if you're
 205  * feeling lucky, this usually works just fine.
 206  */
 207 static void __devexit ioat_remove(struct pci_dev *pdev)
 208 {
 209         struct ioat_device *device = pci_get_drvdata(pdev);
 210
 211         ioat_shutdown_functionality(pdev);
 212
 213         kfree(device);
 214 }
 215
 216 static int __init ioat_init_module(void)
 217 {
 218         return pci_register_driver(&ioat_pci_driver);
 219 }
 220 module_init(ioat_init_module);
 221
 222 static void __exit ioat_exit_module(void)
 223 {
 224         pci_unregister_driver(&ioat_pci_driver);
 225 }
 226 module_exit(ioat_exit_module);