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         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
  43         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
  44         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
  45         { PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
  46         { 0, }
  47 };
  48
  49 struct ioat_device {
  50         struct pci_dev          *pdev;
  51         void __iomem            *iobase;
  52         struct ioatdma_device   *dma;
  53         struct dca_provider     *dca;
  54 };
  55
  56 static int __devinit ioat_probe(struct pci_dev *pdev,
  57                                 const struct pci_device_id *id);
  58 static void __devexit ioat_remove(struct pci_dev *pdev);
  59
  60 static int ioat_dca_enabled = 1;
  61 module_param(ioat_dca_enabled, int, 0644);
  62 MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)");
  63
  64 static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
  65 {
  66         struct ioat_device *device = pci_get_drvdata(pdev);
  67         u8 version;
  68         int err = 0;
  69
  70         version = readb(iobase + IOAT_VER_OFFSET);
  71         switch (version) {
  72         case IOAT_VER_1_2:
  73                 device->dma = ioat_dma_probe(pdev, iobase);
  74                 if (device->dma && ioat_dca_enabled)
  75                         device->dca = ioat_dca_init(pdev, iobase);
  76                 break;
  77         default:
  78                 err = -ENODEV;
  79                 break;
  80         }
  81         return err;
  82 }
  83
  84 static void ioat_shutdown_functionality(struct pci_dev *pdev)
  85 {
  86         struct ioat_device *device = pci_get_drvdata(pdev);
  87
  88         dev_err(&pdev->dev, "Removing dma and dca services\n");
  89         if (device->dca) {
  90                 unregister_dca_provider(device->dca);
  91                 free_dca_provider(device->dca);
  92                 device->dca = NULL;
  93         }
  94
  95         if (device->dma) {
  96                 ioat_dma_remove(device->dma);
  97                 device->dma = NULL;
  98         }
  99 }
 100
 101 static struct pci_driver ioat_pci_driver = {
 102         .name           = "ioatdma",
 103         .id_table       = ioat_pci_tbl,
 104         .probe          = ioat_probe,
 105         .shutdown       = ioat_shutdown_functionality,
 106         .remove         = __devexit_p(ioat_remove),
 107 };
 108
 109 static int __devinit ioat_probe(struct pci_dev *pdev,
 110                                 const struct pci_device_id *id)
 111 {
 112         void __iomem *iobase;
 113         struct ioat_device *device;
 114         unsigned long mmio_start, mmio_len;
 115         int err;
 116
 117         err = pci_enable_device(pdev);
 118         if (err)
 119                 goto err_enable_device;
 120
 121         err = pci_request_regions(pdev, ioat_pci_driver.name);
 122         if (err)
 123                 goto err_request_regions;
 124
 125         err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
 126         if (err)
 127                 err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
 128         if (err)
 129                 goto err_set_dma_mask;
 130
 131         err = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
 132         if (err)
 133                 err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
 134         if (err)
 135                 goto err_set_dma_mask;
 136
 137         mmio_start = pci_resource_start(pdev, 0);
 138         mmio_len = pci_resource_len(pdev, 0);
 139         iobase = ioremap(mmio_start, mmio_len);
 140         if (!iobase) {
 141                 err = -ENOMEM;
 142                 goto err_ioremap;
 143         }
 144
 145         device = kzalloc(sizeof(*device), GFP_KERNEL);
 146         if (!device) {
 147                 err = -ENOMEM;
 148                 goto err_kzalloc;
 149         }
 150         device->pdev = pdev;
 151         pci_set_drvdata(pdev, device);
 152         device->iobase = iobase;
 153
 154         pci_set_master(pdev);
 155
 156         err = ioat_setup_functionality(pdev, iobase);
 157         if (err)
 158                 goto err_version;
 159
 160         return 0;
 161
 162 err_version:
 163         kfree(device);
 164 err_kzalloc:
 165         iounmap(iobase);
 166 err_ioremap:
 167 err_set_dma_mask:
 168         pci_release_regions(pdev);
 169         pci_disable_device(pdev);
 170 err_request_regions:
 171 err_enable_device:
 172         return err;
 173 }
 174
 175 /*
 176  * It is unsafe to remove this module: if removed while a requested
 177  * dma is outstanding, esp. from tcp, it is possible to hang while
 178  * waiting for something that will never finish.  However, if you're
 179  * feeling lucky, this usually works just fine.
 180  */
 181 static void __devexit ioat_remove(struct pci_dev *pdev)
 182 {
 183         struct ioat_device *device = pci_get_drvdata(pdev);
 184
 185         ioat_shutdown_functionality(pdev);
 186
 187         kfree(device);
 188 }
 189
 190 static int __init ioat_init_module(void)
 191 {
 192         return pci_register_driver(&ioat_pci_driver);
 193 }
 194 module_init(ioat_init_module);
 195
 196 static void __exit ioat_exit_module(void)
 197 {
 198         pci_unregister_driver(&ioat_pci_driver);
 199 }
 200 module_exit(ioat_exit_module);