/*
 *      PCI handling of I2O controller
 *
 *      Copyright (C) 1999-2002 Red Hat Software
 *
 *      Written by Alan Cox, Building Number Three Ltd
 *
 *      This program is free software; you can redistribute it and/or modify it
 *      under the terms of the GNU General Public License as published by the
 *      Free Software Foundation; either version 2 of the License, or (at your
 *      option) any later version.
 *
 *      A lot of the I2O message side code from this is taken from the Red
 *      Creek RCPCI45 adapter driver by Red Creek Communications
 *
 *      Fixes/additions:
 *              Philipp Rumpf
 *              Juha Sievänen <Juha.Sievanen@cs.Helsinki.FI>
 *              Auvo Häkkinen <Auvo.Hakkinen@cs.Helsinki.FI>
 *              Deepak Saxena <deepak@plexity.net>
 *              Boji T Kannanthanam <boji.t.kannanthanam@intel.com>
 *              Alan Cox <alan@lxorguk.ukuu.org.uk>:
 *                      Ported to Linux 2.5.
 *              Markus Lidel <Markus.Lidel@shadowconnect.com>:
 *                      Minor fixes for 2.6.
 *              Markus Lidel <Markus.Lidel@shadowconnect.com>:
 *                      Support for sysfs included.
 */

#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/i2o.h>
#include "core.h"

#define OSM_DESCRIPTION "I2O-subsystem"

/* PCI device id table for all I2O controllers */
static struct pci_device_id __devinitdata i2o_pci_ids[] = {
        {PCI_DEVICE_CLASS(PCI_CLASS_INTELLIGENT_I2O << 8, 0xffff00)},
        {PCI_DEVICE(PCI_VENDOR_ID_DPT, 0xa511)},
        {.vendor = PCI_VENDOR_ID_INTEL,.device = 0x1962,
         .subvendor = PCI_VENDOR_ID_PROMISE,.subdevice = PCI_ANY_ID},
        {0}
};

/**
 *      i2o_pci_free - Frees the DMA memory for the I2O controller
 *      @c: I2O controller to free
 *
 *      Remove all allocated DMA memory and unmap memory IO regions. If MTRR
 *      is enabled, also remove it again.
 */
static void i2o_pci_free(struct i2o_controller *c)
{
        struct device *dev;

        dev = &c->pdev->dev;

        i2o_dma_free(dev, &c->out_queue);
        i2o_dma_free(dev, &c->status_block);
        kfree(c->lct);
        i2o_dma_free(dev, &c->dlct);
        i2o_dma_free(dev, &c->hrt);
        i2o_dma_free(dev, &c->status);

        if (c->raptor && c->in_queue.virt)
                iounmap(c->in_queue.virt);

        if (c->base.virt)
                iounmap(c->base.virt);

        pci_release_regions(c->pdev);
}

/**
 *      i2o_pci_alloc - Allocate DMA memory, map IO memory for I2O controller
 *      @c: I2O controller
 *
 *      Allocate DMA memory for a PCI (or in theory AGP) I2O controller. All
 *      IO mappings are also done here. If MTRR is enabled, also do add memory
 *      regions here.
 *
 *      Returns 0 on success or negative error code on failure.
 */
static int __devinit i2o_pci_alloc(struct i2o_controller *c)
{
        struct pci_dev *pdev = c->pdev;
        struct device *dev = &pdev->dev;
        int i;

        if (pci_request_regions(pdev, OSM_DESCRIPTION)) {
                printk(KERN_ERR "%s: device already claimed\n", c->name);
                return -ENODEV;
        }

        for (i = 0; i < 6; i++) {
                /* Skip I/O spaces */
                if (!(pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
                        if (!c->base.phys) {
                                c->base.phys = pci_resource_start(pdev, i);
                                c->base.len = pci_resource_len(pdev, i);

                                /*
                                 * If we know what card it is, set the size
                                 * correctly. Code is taken from dpt_i2o.c
                                 */
                                if (pdev->device == 0xa501) {
                                        if (pdev->subsystem_device >= 0xc032 &&
                                            pdev->subsystem_device <= 0xc03b) {
                                                if (c->base.len > 0x400000)
                                                        c->base.len = 0x400000;
                                        } else {
                                                if (c->base.len > 0x100000)
                                                        c->base.len = 0x100000;
                                        }
                                }
                                if (!c->raptor)
                                        break;
                        } else {
                                c->in_queue.phys = pci_resource_start(pdev, i);
                                c->in_queue.len = pci_resource_len(pdev, i);
                                break;
                        }
                }
        }

        if (i == 6) {
                printk(KERN_ERR "%s: I2O controller has no memory regions"
                       " defined.\n", c->name);
                i2o_pci_free(c);
                return -EINVAL;
        }

        /* Map the I2O controller */
        if (c->raptor) {
                printk(KERN_INFO "%s: PCI I2O controller\n", c->name);
                printk(KERN_INFO "     BAR0 at 0x%08lX size=%ld\n",
                       (unsigned long)c->base.phys, (unsigned long)c->base.len);
                printk(KERN_INFO "     BAR1 at 0x%08lX size=%ld\n",
                       (unsigned long)c->in_queue.phys,
                       (unsigned long)c->in_queue.len);
        } else
                printk(KERN_INFO "%s: PCI I2O controller at %08lX size=%ld\n",
                       c->name, (unsigned long)c->base.phys,
                       (unsigned long)c->base.len);

        c->base.virt = ioremap_nocache(c->base.phys, c->base.len);
        if (!c->base.virt) {
                printk(KERN_ERR "%s: Unable to map controller.\n", c->name);
                i2o_pci_free(c);
                return -ENOMEM;
        }

        if (c->raptor) {
                c->in_queue.virt =
                    ioremap_nocache(c->in_queue.phys, c->in_queue.len);
                if (!c->in_queue.virt) {
                        printk(KERN_ERR "%s: Unable to map controller.\n",
                               c->name);
                        i2o_pci_free(c);
                        return -ENOMEM;
                }
        } else
                c->in_queue = c->base;

        c->irq_status = c->base.virt + I2O_IRQ_STATUS;
        c->irq_mask = c->base.virt + I2O_IRQ_MASK;
        c->in_port = c->base.virt + I2O_IN_PORT;
        c->out_port = c->base.virt + I2O_OUT_PORT;

        /* Motorola/Freescale chip does not follow spec */
        if (pdev->vendor == PCI_VENDOR_ID_MOTOROLA && pdev->device == 0x18c0) {
                /* Check if CPU is enabled */
                if (be32_to_cpu(readl(c->base.virt + 0x10000)) & 0x10000000) {
                        printk(KERN_INFO "%s: MPC82XX needs CPU running to "
                               "service I2O.\n", c->name);
                        i2o_pci_free(c);
                        return -ENODEV;
                } else {
                        c->irq_status += I2O_MOTOROLA_PORT_OFFSET;
                        c->irq_mask += I2O_MOTOROLA_PORT_OFFSET;
                        c->in_port += I2O_MOTOROLA_PORT_OFFSET;
                        c->out_port += I2O_MOTOROLA_PORT_OFFSET;
                        printk(KERN_INFO "%s: MPC82XX workarounds activated.\n",
                               c->name);
                }
        }

        if (i2o_dma_alloc(dev, &c->status, 8)) {
                i2o_pci_free(c);
                return -ENOMEM;
        }

        if (i2o_dma_alloc(dev, &c->hrt, sizeof(i2o_hrt))) {
                i2o_pci_free(c);
                return -ENOMEM;
        }

        if (i2o_dma_alloc(dev, &c->dlct, 8192)) {
                i2o_pci_free(c);
                return -ENOMEM;
        }

        if (i2o_dma_alloc(dev, &c->status_block, sizeof(i2o_status_block))) {
                i2o_pci_free(c);
                return -ENOMEM;
        }

        if (i2o_dma_alloc(dev, &c->out_queue,
                I2O_MAX_OUTBOUND_MSG_FRAMES * I2O_OUTBOUND_MSG_FRAME_SIZE *
                                sizeof(u32))) {
                i2o_pci_free(c);
                return -ENOMEM;
        }

        pci_set_drvdata(pdev, c);

        return 0;
}

/**
 *      i2o_pci_interrupt - Interrupt handler for I2O controller
 *      @irq: interrupt line
 *      @dev_id: pointer to the I2O controller
 *
 *      Handle an interrupt from a PCI based I2O controller. This turns out
 *      to be rather simple. We keep the controller pointer in the cookie.
 */
static irqreturn_t i2o_pci_interrupt(int irq, void *dev_id)
{
        struct i2o_controller *c = dev_id;
        u32 m;
        irqreturn_t rc = IRQ_NONE;

        while (readl(c->irq_status) & I2O_IRQ_OUTBOUND_POST) {
                m = readl(c->out_port);
                if (m == I2O_QUEUE_EMPTY) {
                        /*
                         * Old 960 steppings had a bug in the I2O unit that
                         * caused the queue to appear empty when it wasn't.
                         */
                        m = readl(c->out_port);
                        if (unlikely(m == I2O_QUEUE_EMPTY))
                                break;
                }

                /* dispatch it */
                if (i2o_driver_dispatch(c, m))
                        /* flush it if result != 0 */
                        i2o_flush_reply(c, m);

                rc = IRQ_HANDLED;
        }

        return rc;
}

/**
 *      i2o_pci_irq_enable - Allocate interrupt for I2O controller
 *      @c: i2o_controller that the request is for
 *
 *      Allocate an interrupt for the I2O controller, and activate interrupts
 *      on the I2O controller.
 *
 *      Returns 0 on success or negative error code on failure.
 */
static int i2o_pci_irq_enable(struct i2o_controller *c)
{
        struct pci_dev *pdev = c->pdev;
        int rc;

        writel(0xffffffff, c->irq_mask);

        if (pdev->irq) {
                rc = request_irq(pdev->irq, i2o_pci_interrupt, IRQF_SHARED,
                                 c->name, c);
                if (rc < 0) {
                        printk(KERN_ERR "%s: unable to allocate interrupt %d."
                               "\n", c->name, pdev->irq);
                        return rc;
                }
        }

        writel(0x00000000, c->irq_mask);

        printk(KERN_INFO "%s: Installed at IRQ %d\n", c->name, pdev->irq);

        return 0;
}

/**
 *      i2o_pci_irq_disable - Free interrupt for I2O controller
 *      @c: I2O controller
 *
 *      Disable interrupts in I2O controller and then free interrupt.
 */
static void i2o_pci_irq_disable(struct i2o_controller *c)
{
        writel(0xffffffff, c->irq_mask);

        if (c->pdev->irq > 0)
                free_irq(c->pdev->irq, c);
}

/**
 *      i2o_pci_probe - Probe the PCI device for an I2O controller
 *      @pdev: PCI device to test
 *      @id: id which matched with the PCI device id table
 *
 *      Probe the PCI device for any device which is a memory of the
 *      Intelligent, I2O class or an Adaptec Zero Channel Controller. We
 *      attempt to set up each such device and register it with the core.
 *
 *      Returns 0 on success or negative error code on failure.
 */
static int __devinit i2o_pci_probe(struct pci_dev *pdev,
                                   const struct pci_device_id *id)
{
        struct i2o_controller *c;
        int rc;
        struct pci_dev *i960 = NULL;

        printk(KERN_INFO "i2o: Checking for PCI I2O controllers...\n");

        if ((pdev->class & 0xff) > 1) {
                printk(KERN_WARNING "i2o: %s does not support I2O 1.5 "
                       "(skipping).\n", pci_name(pdev));
                return -ENODEV;
        }

        if ((rc = pci_enable_device(pdev))) {
                printk(KERN_WARNING "i2o: couldn't enable device %s\n",
                       pci_name(pdev));
                return rc;
        }

        if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
                printk(KERN_WARNING "i2o: no suitable DMA found for %s\n",
                       pci_name(pdev));
                rc = -ENODEV;
                goto disable;
        }

        pci_set_master(pdev);

        c = i2o_iop_alloc();
        if (IS_ERR(c)) {
                printk(KERN_ERR "i2o: couldn't allocate memory for %s\n",
                       pci_name(pdev));
                rc = PTR_ERR(c);
                goto disable;
        } else
                printk(KERN_INFO "%s: controller found (%s)\n", c->name,
                       pci_name(pdev));

        c->pdev = pdev;
        c->device.parent = &pdev->dev;

        /* Cards that fall apart if you hit them with large I/O loads... */
        if (pdev->vendor == PCI_VENDOR_ID_NCR && pdev->device == 0x0630) {
                c->short_req = 1;
                printk(KERN_INFO "%s: Symbios FC920 workarounds activated.\n",
                       c->name);
        }

        if (pdev->subsystem_vendor == PCI_VENDOR_ID_PROMISE) {
                /*
                 * Expose the ship behind i960 for initialization, or it will
                 * failed
                 */
                i960 = pci_get_slot(c->pdev->bus,
                                  PCI_DEVFN(PCI_SLOT(c->pdev->devfn), 0));

                if (i960) {
                        pci_write_config_word(i960, 0x42, 0);
                        pci_dev_put(i960);
                }

                c->promise = 1;
                c->limit_sectors = 1;
        }

        if (pdev->subsystem_vendor == PCI_VENDOR_ID_DPT)
                c->adaptec = 1;

        /* Cards that go bananas if you quiesce them before you reset them. */
        if (pdev->vendor == PCI_VENDOR_ID_DPT) {
                c->no_quiesce = 1;
                if (pdev->device == 0xa511)
                        c->raptor = 1;

                if (pdev->subsystem_device == 0xc05a) {
                        c->limit_sectors = 1;
                        printk(KERN_INFO
                               "%s: limit sectors per request to %d\n", c->name,
                               I2O_MAX_SECTORS_LIMITED);
                }
#ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
                if (sizeof(dma_addr_t) > 4) {
                        if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)))
                                printk(KERN_INFO "%s: 64-bit DMA unavailable\n",
                                       c->name);
                        else {
                                c->pae_support = 1;
                                printk(KERN_INFO "%s: using 64-bit DMA\n",
                                       c->name);
                        }
                }
#endif
        }

        if ((rc = i2o_pci_alloc(c))) {
                printk(KERN_ERR "%s: DMA / IO allocation for I2O controller "
                       "failed\n", c->name);
                goto free_controller;
        }

        if (i2o_pci_irq_enable(c)) {
                printk(KERN_ERR "%s: unable to enable interrupts for I2O "
                       "controller\n", c->name);
                goto free_pci;
        }

        if ((rc = i2o_iop_add(c)))
                goto uninstall;

        if (i960)
                pci_write_config_word(i960, 0x42, 0x03ff);

        return 0;

      uninstall:
        i2o_pci_irq_disable(c);

      free_pci:
        i2o_pci_free(c);

      free_controller:
        i2o_iop_free(c);

      disable:
        pci_disable_device(pdev);

        return rc;
}

/**
 *      i2o_pci_remove - Removes a I2O controller from the system
 *      @pdev: I2O controller which should be removed
 *
 *      Reset the I2O controller, disable interrupts and remove all allocated
 *      resources.
 */
static void __devexit i2o_pci_remove(struct pci_dev *pdev)
{
        struct i2o_controller *c;
        c = pci_get_drvdata(pdev);

        i2o_iop_remove(c);
        i2o_pci_irq_disable(c);
        i2o_pci_free(c);

        pci_disable_device(pdev);

        printk(KERN_INFO "%s: Controller removed.\n", c->name);

        put_device(&c->device);
};

/* PCI driver for I2O controller */
static struct pci_driver i2o_pci_driver = {
        .name = "PCI_I2O",
        .id_table = i2o_pci_ids,
        .probe = i2o_pci_probe,
        .remove = __devexit_p(i2o_pci_remove),
};

/**
 *      i2o_pci_init - registers I2O PCI driver in PCI subsystem
 *
 *      Returns > 0 on success or negative error code on failure.
 */
int __init i2o_pci_init(void)
{
        return pci_register_driver(&i2o_pci_driver);
};

/**
 *      i2o_pci_exit - unregisters I2O PCI driver from PCI subsystem
 */
void __exit i2o_pci_exit(void)
{
        pci_unregister_driver(&i2o_pci_driver);
};

MODULE_DEVICE_TABLE(pci, i2o_pci_ids);