/*
   * Intel I/OAT DMA Linux driver

   * Copyright(c) 2007 Intel Corporation.

   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms and conditions of the GNU General Public License,
   * version 2, as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * The full GNU General Public License is included in this distribution in
   * the file called "COPYING".
   *
   */
  
  /*
   * This driver supports an Intel I/OAT DMA engine, which does asynchronous
   * copy operations.
   */
  
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/pci.h>
  #include <linux/interrupt.h>

  #include <linux/dca.h>

  #include "ioatdma.h"
  #include "ioatdma_registers.h"
  #include "ioatdma_hw.h"

  MODULE_VERSION(IOAT_DMA_VERSION);

  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Intel Corporation");
  
  static struct pci_device_id ioat_pci_tbl[] = {

  	/* I/OAT v1 platforms */

  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },

  
  	/* I/OAT v2 platforms */
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB) },

  
  	/* I/OAT v3 platforms */
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG0) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG1) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG2) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG3) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG4) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG5) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG6) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG7) },

  	{ 0, }
  };
  
  struct ioat_device {
  	struct pci_dev		*pdev;
  	void __iomem		*iobase;
  	struct ioatdma_device	*dma;

  	struct dca_provider	*dca;

  };
  
  static int __devinit ioat_probe(struct pci_dev *pdev,
  				const struct pci_device_id *id);

  static void __devexit ioat_remove(struct pci_dev *pdev);

  static int ioat_dca_enabled = 1;
  module_param(ioat_dca_enabled, int, 0644);
  MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)");

  static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
  {
  	struct ioat_device *device = pci_get_drvdata(pdev);
  	u8 version;
  	int err = 0;
  
  	version = readb(iobase + IOAT_VER_OFFSET);
  	switch (version) {
  	case IOAT_VER_1_2:
  		device->dma = ioat_dma_probe(pdev, iobase);

  		if (device->dma && ioat_dca_enabled)

  			device->dca = ioat_dca_init(pdev, iobase);

  		break;

  	case IOAT_VER_2_0:
  		device->dma = ioat_dma_probe(pdev, iobase);
  		if (device->dma && ioat_dca_enabled)
  			device->dca = ioat2_dca_init(pdev, iobase);
  		break;

  	case IOAT_VER_3_0:
  		device->dma = ioat_dma_probe(pdev, iobase);
  		if (device->dma && ioat_dca_enabled)
  			device->dca = ioat3_dca_init(pdev, iobase);
  		break;

  	default:
  		err = -ENODEV;
  		break;
  	}

  	if (!device->dma)
  		err = -ENODEV;

  	return err;
  }
  
  static void ioat_shutdown_functionality(struct pci_dev *pdev)
  {
  	struct ioat_device *device = pci_get_drvdata(pdev);

  	dev_err(&pdev->dev, "Removing dma and dca services
  ");

  	if (device->dca) {
  		unregister_dca_provider(device->dca);
  		free_dca_provider(device->dca);
  		device->dca = NULL;
  	}

  	if (device->dma) {
  		ioat_dma_remove(device->dma);
  		device->dma = NULL;
  	}

  }

  static struct pci_driver ioat_pci_driver = {

  	.name		= "ioatdma",
  	.id_table	= ioat_pci_tbl,
  	.probe		= ioat_probe,
  	.shutdown	= ioat_shutdown_functionality,

  	.remove		= __devexit_p(ioat_remove),

  };
  
  static int __devinit ioat_probe(struct pci_dev *pdev,
  				const struct pci_device_id *id)
  {
  	void __iomem *iobase;
  	struct ioat_device *device;
  	unsigned long mmio_start, mmio_len;
  	int err;
  
  	err = pci_enable_device(pdev);
  	if (err)
  		goto err_enable_device;

  	err = pci_request_regions(pdev, ioat_pci_driver.name);

  	if (err)
  		goto err_request_regions;
  
  	err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
  	if (err)
  		err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
  	if (err)
  		goto err_set_dma_mask;
  
  	err = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
  	if (err)
  		err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
  	if (err)
  		goto err_set_dma_mask;
  
  	mmio_start = pci_resource_start(pdev, 0);
  	mmio_len = pci_resource_len(pdev, 0);
  	iobase = ioremap(mmio_start, mmio_len);
  	if (!iobase) {
  		err = -ENOMEM;
  		goto err_ioremap;
  	}
  
  	device = kzalloc(sizeof(*device), GFP_KERNEL);
  	if (!device) {
  		err = -ENOMEM;
  		goto err_kzalloc;
  	}
  	device->pdev = pdev;
  	pci_set_drvdata(pdev, device);
  	device->iobase = iobase;
  
  	pci_set_master(pdev);
  
  	err = ioat_setup_functionality(pdev, iobase);
  	if (err)
  		goto err_version;
  
  	return 0;
  
  err_version:
  	kfree(device);
  err_kzalloc:
  	iounmap(iobase);
  err_ioremap:
  err_set_dma_mask:
  	pci_release_regions(pdev);
  	pci_disable_device(pdev);
  err_request_regions:
  err_enable_device:
  	return err;
  }

  /*
   * It is unsafe to remove this module: if removed while a requested
   * dma is outstanding, esp. from tcp, it is possible to hang while

   * waiting for something that will never finish.  However, if you're
   * feeling lucky, this usually works just fine.

   */
  static void __devexit ioat_remove(struct pci_dev *pdev)
  {
  	struct ioat_device *device = pci_get_drvdata(pdev);
  
  	ioat_shutdown_functionality(pdev);
  
  	kfree(device);

  }

  
  static int __init ioat_init_module(void)
  {

  	return pci_register_driver(&ioat_pci_driver);

  }
  module_init(ioat_init_module);
  
  static void __exit ioat_exit_module(void)
  {

  	pci_unregister_driver(&ioat_pci_driver);

  }
  module_exit(ioat_exit_module);