/*
 * Intel MIC Platform Software Stack (MPSS)
 *
 * Copyright(c) 2013 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms 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.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Intel MIC Host driver.
 *
 * Global TODO's across the driver to be added after initial base
 * patches are accepted upstream:
 * 1) Enable DMA support.
 * 2) Enable per vring interrupt support.
 */
#include <linux/fs.h>
#include <linux/idr.h>
#include <linux/module.h>
#include <linux/pci.h>

#include "../common/mic_device.h"
#include "mic_device.h"
#include "mic_x100.h"

static const char mic_driver_name[] = "mic";

static DEFINE_PCI_DEVICE_TABLE(mic_pci_tbl) = {
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2250)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2251)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2252)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2253)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2254)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2255)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2256)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2257)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2258)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_2259)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_225a)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_225b)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_225c)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_225d)},
	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MIC_X100_PCI_DEVICE_225e)},

	/* required last entry */
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, mic_pci_tbl);

/* ID allocator for MIC devices */
static struct ida g_mic_ida;
/* Class of MIC devices for sysfs accessibility. */
static struct class *g_mic_class;
/* Base device node number for MIC devices */
static dev_t g_mic_devno;

/**
 * mic_ops_init: Initialize HW specific operation tables.
 *
 * @mdev: pointer to mic_device instance
 *
 * returns none.
 */
static void mic_ops_init(struct mic_device *mdev)
{
	switch (mdev->family) {
	case MIC_FAMILY_X100:
		mdev->ops = &mic_x100_ops;
		break;
	default:
		break;
	}
}

/**
 * mic_get_family - Determine hardware family to which this MIC belongs.
 *
 * @pdev: The pci device structure
 *
 * returns family.
 */
static enum mic_hw_family mic_get_family(struct pci_dev *pdev)
{
	enum mic_hw_family family;

	switch (pdev->device) {
	case MIC_X100_PCI_DEVICE_2250:
	case MIC_X100_PCI_DEVICE_2251:
	case MIC_X100_PCI_DEVICE_2252:
	case MIC_X100_PCI_DEVICE_2253:
	case MIC_X100_PCI_DEVICE_2254:
	case MIC_X100_PCI_DEVICE_2255:
	case MIC_X100_PCI_DEVICE_2256:
	case MIC_X100_PCI_DEVICE_2257:
	case MIC_X100_PCI_DEVICE_2258:
	case MIC_X100_PCI_DEVICE_2259:
	case MIC_X100_PCI_DEVICE_225a:
	case MIC_X100_PCI_DEVICE_225b:
	case MIC_X100_PCI_DEVICE_225c:
	case MIC_X100_PCI_DEVICE_225d:
	case MIC_X100_PCI_DEVICE_225e:
		family = MIC_FAMILY_X100;
		break;
	default:
		family = MIC_FAMILY_UNKNOWN;
		break;
	}
	return family;
}

/**
 * mic_device_init - Allocates and initializes the MIC device structure
 *
 * @mdev: pointer to mic_device instance
 * @pdev: The pci device structure
 *
 * returns none.
 */
static void
mic_device_init(struct mic_device *mdev, struct pci_dev *pdev)
{
	mdev->family = mic_get_family(pdev);
	mdev->stepping = pdev->revision;
	mic_ops_init(mdev);
	mic_sysfs_init(mdev);
}

/**
 * mic_probe - Device Initialization Routine
 *
 * @pdev: PCI device structure
 * @ent: entry in mic_pci_tbl
 *
 * returns 0 on success, < 0 on failure.
 */
static int mic_probe(struct pci_dev *pdev,
		const struct pci_device_id *ent)
{
	int rc;
	struct mic_device *mdev;

	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
	if (!mdev) {
		rc = -ENOMEM;
		dev_err(&pdev->dev, "mdev kmalloc failed rc %d\n", rc);
		goto mdev_alloc_fail;
	}
	mdev->id = ida_simple_get(&g_mic_ida, 0, MIC_MAX_NUM_DEVS, GFP_KERNEL);
	if (mdev->id < 0) {
		rc = mdev->id;
		dev_err(&pdev->dev, "ida_simple_get failed rc %d\n", rc);
		goto ida_fail;
	}

	mic_device_init(mdev, pdev);

	rc = pci_enable_device(pdev);
	if (rc) {
		dev_err(&pdev->dev, "failed to enable pci device.\n");
		goto ida_remove;
	}

	pci_set_master(pdev);

	rc = pci_request_regions(pdev, mic_driver_name);
	if (rc) {
		dev_err(&pdev->dev, "failed to get pci regions.\n");
		goto disable_device;
	}

	rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
	if (rc) {
		dev_err(&pdev->dev, "Cannot set DMA mask\n");
		goto release_regions;
	}

	mdev->mmio.pa = pci_resource_start(pdev, mdev->ops->mmio_bar);
	mdev->mmio.len = pci_resource_len(pdev, mdev->ops->mmio_bar);
	mdev->mmio.va = pci_ioremap_bar(pdev, mdev->ops->mmio_bar);
	if (!mdev->mmio.va) {
		dev_err(&pdev->dev, "Cannot remap MMIO BAR\n");
		rc = -EIO;
		goto release_regions;
	}

	mdev->aper.pa = pci_resource_start(pdev, mdev->ops->aper_bar);
	mdev->aper.len = pci_resource_len(pdev, mdev->ops->aper_bar);
	mdev->aper.va = ioremap_wc(mdev->aper.pa, mdev->aper.len);
	if (!mdev->aper.va) {
		dev_err(&pdev->dev, "Cannot remap Aperture BAR\n");
		rc = -EIO;
		goto unmap_mmio;
	}

	pci_set_drvdata(pdev, mdev);

	mdev->sdev = device_create_with_groups(g_mic_class, &pdev->dev,
		MKDEV(MAJOR(g_mic_devno), mdev->id), NULL,
		mdev->attr_group, "mic%d", mdev->id);
	if (IS_ERR(mdev->sdev)) {
		rc = PTR_ERR(mdev->sdev);
		dev_err(&pdev->dev,
			"device_create_with_groups failed rc %d\n", rc);
		goto unmap_aper;
	}
	return 0;
unmap_aper:
	iounmap(mdev->aper.va);
unmap_mmio:
	iounmap(mdev->mmio.va);
release_regions:
	pci_release_regions(pdev);
disable_device:
	pci_disable_device(pdev);
ida_remove:
	ida_simple_remove(&g_mic_ida, mdev->id);
ida_fail:
	kfree(mdev);
mdev_alloc_fail:
	dev_err(&pdev->dev, "Probe failed rc %d\n", rc);
	return rc;
}

/**
 * mic_remove - Device Removal Routine
 * mic_remove is called by the PCI subsystem to alert the driver
 * that it should release a PCI device.
 *
 * @pdev: PCI device structure
 */
static void mic_remove(struct pci_dev *pdev)
{
	struct mic_device *mdev;

	mdev = pci_get_drvdata(pdev);
	if (!mdev)
		return;

	device_destroy(g_mic_class, MKDEV(MAJOR(g_mic_devno), mdev->id));
	iounmap(mdev->mmio.va);
	iounmap(mdev->aper.va);
	pci_release_regions(pdev);
	pci_disable_device(pdev);
	ida_simple_remove(&g_mic_ida, mdev->id);
	kfree(mdev);
}
static struct pci_driver mic_driver = {
	.name = mic_driver_name,
	.id_table = mic_pci_tbl,
	.probe = mic_probe,
	.remove = mic_remove
};

static int __init mic_init(void)
{
	int ret;

	ret = alloc_chrdev_region(&g_mic_devno, 0,
		MIC_MAX_NUM_DEVS, mic_driver_name);
	if (ret) {
		pr_err("alloc_chrdev_region failed ret %d\n", ret);
		goto error;
	}

	g_mic_class = class_create(THIS_MODULE, mic_driver_name);
	if (IS_ERR(g_mic_class)) {
		ret = PTR_ERR(g_mic_class);
		pr_err("class_create failed ret %d\n", ret);
		goto cleanup_chrdev;
	}

	ida_init(&g_mic_ida);
	ret = pci_register_driver(&mic_driver);
	if (ret) {
		pr_err("pci_register_driver failed ret %d\n", ret);
		goto class_destroy;
	}
	return ret;
class_destroy:
	class_destroy(g_mic_class);
cleanup_chrdev:
	unregister_chrdev_region(g_mic_devno, MIC_MAX_NUM_DEVS);
error:
	return ret;
}

static void __exit mic_exit(void)
{
	pci_unregister_driver(&mic_driver);
	ida_destroy(&g_mic_ida);
	class_destroy(g_mic_class);
	unregister_chrdev_region(g_mic_devno, MIC_MAX_NUM_DEVS);
}

module_init(mic_init);
module_exit(mic_exit);

MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("Intel(R) MIC X100 Host driver");
MODULE_LICENSE("GPL v2");