// SPDX-License-Identifier: GPL-2.0+
/*
 * IBM Hot Plug Controller Driver
 *
 * Written By: Chuck Cole, Jyoti Shah, Tong Yu, Irene Zubarev, IBM Corporation
 *
 * Copyright (C) 2001,2003 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001-2003 IBM Corp.
 *
 * All rights reserved.
 *
 * Send feedback to <gregkh@us.ibm.com>
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include "../pci.h"
#include <asm/pci_x86.h>                /* for struct irq_routing_table */
#include <asm/io_apic.h>
#include "ibmphp.h"

#define attn_on(sl)  ibmphp_hpc_writeslot(sl, HPC_SLOT_ATTNON)
#define attn_off(sl) ibmphp_hpc_writeslot(sl, HPC_SLOT_ATTNOFF)
#define attn_LED_blink(sl) ibmphp_hpc_writeslot(sl, HPC_SLOT_BLINKLED)
#define get_ctrl_revision(sl, rev) ibmphp_hpc_readslot(sl, READ_REVLEVEL, rev)
#define get_hpc_options(sl, opt) ibmphp_hpc_readslot(sl, READ_HPCOPTIONS, opt)

#define DRIVER_VERSION  "0.6"
#define DRIVER_DESC     "IBM Hot Plug PCI Controller Driver"

int ibmphp_debug;

static bool debug;
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION(DRIVER_DESC);

struct pci_bus *ibmphp_pci_bus;
static int max_slots;

static int irqs[16];    /* PIC mode IRQs we're using so far (in case MPS
                         * tables don't provide default info for empty slots */

static int init_flag;

/*
static int get_max_adapter_speed_1 (struct hotplug_slot *, u8 *, u8);

static inline int get_max_adapter_speed (struct hotplug_slot *hs, u8 *value)
{
        return get_max_adapter_speed_1 (hs, value, 1);
}
*/
static inline int get_cur_bus_info(struct slot **sl)
{
        int rc = 1;
        struct slot *slot_cur = *sl;

        debug("options = %x\n", slot_cur->ctrl->options);
        debug("revision = %x\n", slot_cur->ctrl->revision);

        if (READ_BUS_STATUS(slot_cur->ctrl))
                rc = ibmphp_hpc_readslot(slot_cur, READ_BUSSTATUS, NULL);

        if (rc)
                return rc;

        slot_cur->bus_on->current_speed = CURRENT_BUS_SPEED(slot_cur->busstatus);
        if (READ_BUS_MODE(slot_cur->ctrl))
                slot_cur->bus_on->current_bus_mode =
                                CURRENT_BUS_MODE(slot_cur->busstatus);
        else
                slot_cur->bus_on->current_bus_mode = 0xFF;

        debug("busstatus = %x, bus_speed = %x, bus_mode = %x\n",
                        slot_cur->busstatus,
                        slot_cur->bus_on->current_speed,
                        slot_cur->bus_on->current_bus_mode);

        *sl = slot_cur;
        return 0;
}

static inline int slot_update(struct slot **sl)
{
        int rc;
        rc = ibmphp_hpc_readslot(*sl, READ_ALLSTAT, NULL);
        if (rc)
                return rc;
        if (!init_flag)
                rc = get_cur_bus_info(sl);
        return rc;
}

static int __init get_max_slots(void)
{
        struct slot *slot_cur;
        u8 slot_count = 0;

        list_for_each_entry(slot_cur, &ibmphp_slot_head, ibm_slot_list) {
                /* sometimes the hot-pluggable slots start with 4 (not always from 1) */
                slot_count = max(slot_count, slot_cur->number);
        }
        return slot_count;
}

/* This routine will put the correct slot->device information per slot.  It's
 * called from initialization of the slot structures. It will also assign
 * interrupt numbers per each slot.
 * Parameters: struct slot
 * Returns 0 or errors
 */
int ibmphp_init_devno(struct slot **cur_slot)
{
        struct irq_routing_table *rtable;
        int len;
        int loop;
        int i;

        rtable = pcibios_get_irq_routing_table();
        if (!rtable) {
                err("no BIOS routing table...\n");
                return -ENOMEM;
        }

        len = (rtable->size - sizeof(struct irq_routing_table)) /
                        sizeof(struct irq_info);

        if (!len) {
                kfree(rtable);
                return -1;
        }
        for (loop = 0; loop < len; loop++) {
                if ((*cur_slot)->number == rtable->slots[loop].slot &&
                    (*cur_slot)->bus == rtable->slots[loop].bus) {
                        (*cur_slot)->device = PCI_SLOT(rtable->slots[loop].devfn);
                        for (i = 0; i < 4; i++)
                                (*cur_slot)->irq[i] = IO_APIC_get_PCI_irq_vector((int) (*cur_slot)->bus,
                                                (int) (*cur_slot)->device, i);

                        debug("(*cur_slot)->irq[0] = %x\n",
                                        (*cur_slot)->irq[0]);
                        debug("(*cur_slot)->irq[1] = %x\n",
                                        (*cur_slot)->irq[1]);
                        debug("(*cur_slot)->irq[2] = %x\n",
                                        (*cur_slot)->irq[2]);
                        debug("(*cur_slot)->irq[3] = %x\n",
                                        (*cur_slot)->irq[3]);

                        debug("rtable->exclusive_irqs = %x\n",
                                        rtable->exclusive_irqs);
                        debug("rtable->slots[loop].irq[0].bitmap = %x\n",
                                        rtable->slots[loop].irq[0].bitmap);
                        debug("rtable->slots[loop].irq[1].bitmap = %x\n",
                                        rtable->slots[loop].irq[1].bitmap);
                        debug("rtable->slots[loop].irq[2].bitmap = %x\n",
                                        rtable->slots[loop].irq[2].bitmap);
                        debug("rtable->slots[loop].irq[3].bitmap = %x\n",
                                        rtable->slots[loop].irq[3].bitmap);

                        debug("rtable->slots[loop].irq[0].link = %x\n",
                                        rtable->slots[loop].irq[0].link);
                        debug("rtable->slots[loop].irq[1].link = %x\n",
                                        rtable->slots[loop].irq[1].link);
                        debug("rtable->slots[loop].irq[2].link = %x\n",
                                        rtable->slots[loop].irq[2].link);
                        debug("rtable->slots[loop].irq[3].link = %x\n",
                                        rtable->slots[loop].irq[3].link);
                        debug("end of init_devno\n");
                        kfree(rtable);
                        return 0;
                }
        }

        kfree(rtable);
        return -1;
}

static inline int power_on(struct slot *slot_cur)
{
        u8 cmd = HPC_SLOT_ON;
        int retval;

        retval = ibmphp_hpc_writeslot(slot_cur, cmd);
        if (retval) {
                err("power on failed\n");
                return retval;
        }
        if (CTLR_RESULT(slot_cur->ctrl->status)) {
                err("command not completed successfully in power_on\n");
                return -EIO;
        }
        msleep(3000);   /* For ServeRAID cards, and some 66 PCI */
        return 0;
}

static inline int power_off(struct slot *slot_cur)
{
        u8 cmd = HPC_SLOT_OFF;
        int retval;

        retval = ibmphp_hpc_writeslot(slot_cur, cmd);
        if (retval) {
                err("power off failed\n");
                return retval;
        }
        if (CTLR_RESULT(slot_cur->ctrl->status)) {
                err("command not completed successfully in power_off\n");
                retval = -EIO;
        }
        return retval;
}

static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 value)
{
        int rc = 0;
        struct slot *pslot;
        u8 cmd = 0x00;     /* avoid compiler warning */

        debug("set_attention_status - Entry hotplug_slot[%lx] value[%x]\n",
                        (ulong) hotplug_slot, value);
        ibmphp_lock_operations();


        if (hotplug_slot) {
                switch (value) {
                case HPC_SLOT_ATTN_OFF:
                        cmd = HPC_SLOT_ATTNOFF;
                        break;
                case HPC_SLOT_ATTN_ON:
                        cmd = HPC_SLOT_ATTNON;
                        break;
                case HPC_SLOT_ATTN_BLINK:
                        cmd = HPC_SLOT_BLINKLED;
                        break;
                default:
                        rc = -ENODEV;
                        err("set_attention_status - Error : invalid input [%x]\n",
                                        value);
                        break;
                }
                if (rc == 0) {
                        pslot = to_slot(hotplug_slot);
                        rc = ibmphp_hpc_writeslot(pslot, cmd);
                }
        } else
                rc = -ENODEV;

        ibmphp_unlock_operations();

        debug("set_attention_status - Exit rc[%d]\n", rc);
        return rc;
}

static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
        int rc = -ENODEV;
        struct slot *pslot;
        struct slot myslot;

        debug("get_attention_status - Entry hotplug_slot[%lx] pvalue[%lx]\n",
                                        (ulong) hotplug_slot, (ulong) value);

        ibmphp_lock_operations();
        if (hotplug_slot) {
                pslot = to_slot(hotplug_slot);
                memcpy(&myslot, pslot, sizeof(struct slot));
                rc = ibmphp_hpc_readslot(pslot, READ_SLOTSTATUS,
                                         &myslot.status);
                if (!rc)
                        rc = ibmphp_hpc_readslot(pslot, READ_EXTSLOTSTATUS,
                                                 &myslot.ext_status);
                if (!rc)
                        *value = SLOT_ATTN(myslot.status, myslot.ext_status);
        }

        ibmphp_unlock_operations();
        debug("get_attention_status - Exit rc[%d] value[%x]\n", rc, *value);
        return rc;
}

static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
        int rc = -ENODEV;
        struct slot *pslot;
        struct slot myslot;

        debug("get_latch_status - Entry hotplug_slot[%lx] pvalue[%lx]\n",
                                        (ulong) hotplug_slot, (ulong) value);
        ibmphp_lock_operations();
        if (hotplug_slot) {
                pslot = to_slot(hotplug_slot);
                memcpy(&myslot, pslot, sizeof(struct slot));
                rc = ibmphp_hpc_readslot(pslot, READ_SLOTSTATUS,
                                         &myslot.status);
                if (!rc)
                        *value = SLOT_LATCH(myslot.status);
        }

        ibmphp_unlock_operations();
        debug("get_latch_status - Exit rc[%d] rc[%x] value[%x]\n",
                        rc, rc, *value);
        return rc;
}


static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
        int rc = -ENODEV;
        struct slot *pslot;
        struct slot myslot;

        debug("get_power_status - Entry hotplug_slot[%lx] pvalue[%lx]\n",
                                        (ulong) hotplug_slot, (ulong) value);
        ibmphp_lock_operations();
        if (hotplug_slot) {
                pslot = to_slot(hotplug_slot);
                memcpy(&myslot, pslot, sizeof(struct slot));
                rc = ibmphp_hpc_readslot(pslot, READ_SLOTSTATUS,
                                         &myslot.status);
                if (!rc)
                        *value = SLOT_PWRGD(myslot.status);
        }

        ibmphp_unlock_operations();
        debug("get_power_status - Exit rc[%d] rc[%x] value[%x]\n",
                        rc, rc, *value);
        return rc;
}

static int get_adapter_present(struct hotplug_slot *hotplug_slot, u8 *value)
{
        int rc = -ENODEV;
        struct slot *pslot;
        u8 present;
        struct slot myslot;

        debug("get_adapter_status - Entry hotplug_slot[%lx] pvalue[%lx]\n",
                                        (ulong) hotplug_slot, (ulong) value);
        ibmphp_lock_operations();
        if (hotplug_slot) {
                pslot = to_slot(hotplug_slot);
                memcpy(&myslot, pslot, sizeof(struct slot));
                rc = ibmphp_hpc_readslot(pslot, READ_SLOTSTATUS,
                                         &myslot.status);
                if (!rc) {
                        present = SLOT_PRESENT(myslot.status);
                        if (present == HPC_SLOT_EMPTY)
                                *value = 0;
                        else
                                *value = 1;
                }
        }

        ibmphp_unlock_operations();
        debug("get_adapter_present - Exit rc[%d] value[%x]\n", rc, *value);
        return rc;
}

static int get_max_bus_speed(struct slot *slot)
{
        int rc = 0;
        u8 mode = 0;
        enum pci_bus_speed speed;
        struct pci_bus *bus = slot->hotplug_slot.pci_slot->bus;

        debug("%s - Entry slot[%p]\n", __func__, slot);

        ibmphp_lock_operations();
        mode = slot->supported_bus_mode;
        speed = slot->supported_speed;
        ibmphp_unlock_operations();

        switch (speed) {
        case BUS_SPEED_33:
                break;
        case BUS_SPEED_66:
                if (mode == BUS_MODE_PCIX)
                        speed += 0x01;
                break;
        case BUS_SPEED_100:
        case BUS_SPEED_133:
                speed += 0x01;
                break;
        default:
                /* Note (will need to change): there would be soon 256, 512 also */
                rc = -ENODEV;
        }

        if (!rc)
                bus->max_bus_speed = speed;

        debug("%s - Exit rc[%d] speed[%x]\n", __func__, rc, speed);
        return rc;
}

/*
static int get_max_adapter_speed_1(struct hotplug_slot *hotplug_slot, u8 *value, u8 flag)
{
        int rc = -ENODEV;
        struct slot *pslot;
        struct slot myslot;

        debug("get_max_adapter_speed_1 - Entry hotplug_slot[%lx] pvalue[%lx]\n",
                                                (ulong)hotplug_slot, (ulong) value);

        if (flag)
                ibmphp_lock_operations();

        if (hotplug_slot && value) {
                pslot = hotplug_slot->private;
                if (pslot) {
                        memcpy(&myslot, pslot, sizeof(struct slot));
                        rc = ibmphp_hpc_readslot(pslot, READ_SLOTSTATUS,
                                                &(myslot.status));

                        if (!(SLOT_LATCH (myslot.status)) &&
                                        (SLOT_PRESENT (myslot.status))) {
                                rc = ibmphp_hpc_readslot(pslot,
                                                READ_EXTSLOTSTATUS,
                                                &(myslot.ext_status));
                                if (!rc)
                                        *value = SLOT_SPEED(myslot.ext_status);
                        } else
                                *value = MAX_ADAPTER_NONE;
                }
        }

        if (flag)
                ibmphp_unlock_operations();

        debug("get_max_adapter_speed_1 - Exit rc[%d] value[%x]\n", rc, *value);
        return rc;
}

static int get_bus_name(struct hotplug_slot *hotplug_slot, char *value)
{
        int rc = -ENODEV;
        struct slot *pslot = NULL;

        debug("get_bus_name - Entry hotplug_slot[%lx]\n", (ulong)hotplug_slot);

        ibmphp_lock_operations();

        if (hotplug_slot) {
                pslot = hotplug_slot->private;
                if (pslot) {
                        rc = 0;
                        snprintf(value, 100, "Bus %x", pslot->bus);
                }
        } else
                rc = -ENODEV;

        ibmphp_unlock_operations();
        debug("get_bus_name - Exit rc[%d] value[%x]\n", rc, *value);
        return rc;
}
*/

/****************************************************************************
 * This routine will initialize the ops data structure used in the validate
 * function. It will also power off empty slots that are powered on since BIOS
 * leaves those on, albeit disconnected
 ****************************************************************************/
static int __init init_ops(void)
{
        struct slot *slot_cur;
        int retval;
        int rc;

        list_for_each_entry(slot_cur, &ibmphp_slot_head, ibm_slot_list) {
                debug("BEFORE GETTING SLOT STATUS, slot # %x\n",
                                                        slot_cur->number);
                if (slot_cur->ctrl->revision == 0xFF)
                        if (get_ctrl_revision(slot_cur,
                                                &slot_cur->ctrl->revision))
                                return -1;

                if (slot_cur->bus_on->current_speed == 0xFF)
                        if (get_cur_bus_info(&slot_cur))
                                return -1;
                get_max_bus_speed(slot_cur);

                if (slot_cur->ctrl->options == 0xFF)
                        if (get_hpc_options(slot_cur, &slot_cur->ctrl->options))
                                return -1;

                retval = slot_update(&slot_cur);
                if (retval)
                        return retval;

                debug("status = %x\n", slot_cur->status);
                debug("ext_status = %x\n", slot_cur->ext_status);
                debug("SLOT_POWER = %x\n", SLOT_POWER(slot_cur->status));
                debug("SLOT_PRESENT = %x\n", SLOT_PRESENT(slot_cur->status));
                debug("SLOT_LATCH = %x\n", SLOT_LATCH(slot_cur->status));

                if ((SLOT_PWRGD(slot_cur->status)) &&
                    !(SLOT_PRESENT(slot_cur->status)) &&
                    !(SLOT_LATCH(slot_cur->status))) {
                        debug("BEFORE POWER OFF COMMAND\n");
                                rc = power_off(slot_cur);
                                if (rc)
                                        return rc;

        /*              retval = slot_update(&slot_cur);
         *              if (retval)
         *                      return retval;
         *              ibmphp_update_slot_info(slot_cur);
         */
                }
        }
        init_flag = 0;
        return 0;
}

/* This operation will check whether the slot is within the bounds and
 * the operation is valid to perform on that slot
 * Parameters: slot, operation
 * Returns: 0 or error codes
 */
static int validate(struct slot *slot_cur, int opn)
{
        int number;
        int retval;

        if (!slot_cur)
                return -ENODEV;
        number = slot_cur->number;
        if ((number > max_slots) || (number < 0))
                return -EBADSLT;
        debug("slot_number in validate is %d\n", slot_cur->number);

        retval = slot_update(&slot_cur);
        if (retval)
                return retval;

        switch (opn) {
                case ENABLE:
                        if (!(SLOT_PWRGD(slot_cur->status)) &&
                             (SLOT_PRESENT(slot_cur->status)) &&
                             !(SLOT_LATCH(slot_cur->status)))
                                return 0;
                        break;
                case DISABLE:
                        if ((SLOT_PWRGD(slot_cur->status)) &&
                            (SLOT_PRESENT(slot_cur->status)) &&
                            !(SLOT_LATCH(slot_cur->status)))
                                return 0;
                        break;
                default:
                        break;
        }
        err("validate failed....\n");
        return -EINVAL;
}

/****************************************************************************
 * This routine is for updating the data structures in the hotplug core
 * Parameters: struct slot
 * Returns: 0 or error
 ****************************************************************************/
int ibmphp_update_slot_info(struct slot *slot_cur)
{
        struct pci_bus *bus = slot_cur->hotplug_slot.pci_slot->bus;
        u8 bus_speed;
        u8 mode;

        bus_speed = slot_cur->bus_on->current_speed;
        mode = slot_cur->bus_on->current_bus_mode;

        switch (bus_speed) {
                case BUS_SPEED_33:
                        break;
                case BUS_SPEED_66:
                        if (mode == BUS_MODE_PCIX)
                                bus_speed += 0x01;
                        else if (mode == BUS_MODE_PCI)
                                ;
                        else
                                bus_speed = PCI_SPEED_UNKNOWN;
                        break;
                case BUS_SPEED_100:
                case BUS_SPEED_133:
                        bus_speed += 0x01;
                        break;
                default:
                        bus_speed = PCI_SPEED_UNKNOWN;
        }

        bus->cur_bus_speed = bus_speed;
        // To do: bus_names

        return 0;
}


/******************************************************************************
 * This function will return the pci_func, given bus and devfunc, or NULL.  It
 * is called from visit routines
 ******************************************************************************/

static struct pci_func *ibm_slot_find(u8 busno, u8 device, u8 function)
{
        struct pci_func *func_cur;
        struct slot *slot_cur;
        list_for_each_entry(slot_cur, &ibmphp_slot_head, ibm_slot_list) {
                if (slot_cur->func) {
                        func_cur = slot_cur->func;
                        while (func_cur) {
                                if ((func_cur->busno == busno) &&
                                                (func_cur->device == device) &&
                                                (func_cur->function == function))
                                        return func_cur;
                                func_cur = func_cur->next;
                        }
                }
        }
        return NULL;
}

/*************************************************************
 * This routine frees up memory used by struct slot, including
 * the pointers to pci_func, bus, hotplug_slot, controller,
 * and deregistering from the hotplug core
 *************************************************************/
static void free_slots(void)
{
        struct slot *slot_cur, *next;

        debug("%s -- enter\n", __func__);

        list_for_each_entry_safe(slot_cur, next, &ibmphp_slot_head,
                                 ibm_slot_list) {
                pci_hp_del(&slot_cur->hotplug_slot);
                slot_cur->ctrl = NULL;
                slot_cur->bus_on = NULL;

                /*
                 * We don't want to actually remove the resources,
                 * since ibmphp_free_resources() will do just that.
                 */
                ibmphp_unconfigure_card(&slot_cur, -1);

                pci_hp_destroy(&slot_cur->hotplug_slot);
                kfree(slot_cur);
        }
        debug("%s -- exit\n", __func__);
}

static void ibm_unconfigure_device(struct pci_func *func)
{
        struct pci_dev *temp;
        u8 j;

        debug("inside %s\n", __func__);
        debug("func->device = %x, func->function = %x\n",
                                        func->device, func->function);
        debug("func->device << 3 | 0x0  = %x\n", func->device << 3 | 0x0);

        pci_lock_rescan_remove();

        for (j = 0; j < 0x08; j++) {
                temp = pci_get_domain_bus_and_slot(0, func->busno,
                                                   (func->device << 3) | j);
                if (temp) {
                        pci_stop_and_remove_bus_device(temp);
                        pci_dev_put(temp);
                }
        }

        pci_dev_put(func->dev);

        pci_unlock_rescan_remove();
}

/*
 * The following function is to fix kernel bug regarding
 * getting bus entries, here we manually add those primary
 * bus entries to kernel bus structure whenever apply
 */
static u8 bus_structure_fixup(u8 busno)
{
        struct pci_bus *bus, *b;
        struct pci_dev *dev;
        u16 l;

        if (pci_find_bus(0, busno) || !(ibmphp_find_same_bus_num(busno)))
                return 1;

        bus = kmalloc(sizeof(*bus), GFP_KERNEL);
        if (!bus)
                return 1;

        dev = kmalloc(sizeof(*dev), GFP_KERNEL);
        if (!dev) {
                kfree(bus);
                return 1;
        }

        bus->number = busno;
        bus->ops = ibmphp_pci_bus->ops;
        dev->bus = bus;
        for (dev->devfn = 0; dev->devfn < 256; dev->devfn += 8) {
                if (!pci_read_config_word(dev, PCI_VENDOR_ID, &l) &&
                                        (l != 0x0000) && (l != 0xffff)) {
                        debug("%s - Inside bus_structure_fixup()\n",
                                                        __func__);
                        b = pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL);
                        if (!b)
                                continue;

                        pci_bus_add_devices(b);
                        break;
                }
        }

        kfree(dev);
        kfree(bus);

        return 0;
}

static int ibm_configure_device(struct pci_func *func)
{
        struct pci_bus *child;
        int num;
        int flag = 0;   /* this is to make sure we don't double scan the bus,
                                        for bridged devices primarily */

        pci_lock_rescan_remove();

        if (!(bus_structure_fixup(func->busno)))
                flag = 1;
        if (func->dev == NULL)
                func->dev = pci_get_domain_bus_and_slot(0, func->busno,
                                PCI_DEVFN(func->device, func->function));

        if (func->dev == NULL) {
                struct pci_bus *bus = pci_find_bus(0, func->busno);
                if (!bus)
                        goto out;

                num = pci_scan_slot(bus,
                                PCI_DEVFN(func->device, func->function));
                if (num)
                        pci_bus_add_devices(bus);

                func->dev = pci_get_domain_bus_and_slot(0, func->busno,
                                PCI_DEVFN(func->device, func->function));
                if (func->dev == NULL) {
                        err("ERROR... : pci_dev still NULL\n");
                        goto out;
                }
        }
        if (!(flag) && (func->dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)) {
                pci_hp_add_bridge(func->dev);
                child = func->dev->subordinate;
                if (child)
                        pci_bus_add_devices(child);
        }

 out:
        pci_unlock_rescan_remove();
        return 0;
}

/*******************************************************
 * Returns whether the bus is empty or not
 *******************************************************/
static int is_bus_empty(struct slot *slot_cur)
{
        int rc;
        struct slot *tmp_slot;
        u8 i = slot_cur->bus_on->slot_min;

        while (i <= slot_cur->bus_on->slot_max) {
                if (i == slot_cur->number) {
                        i++;
                        continue;
                }
                tmp_slot = ibmphp_get_slot_from_physical_num(i);
                if (!tmp_slot)
                        return 0;
                rc = slot_update(&tmp_slot);
                if (rc)
                        return 0;
                if (SLOT_PRESENT(tmp_slot->status) &&
                                        SLOT_PWRGD(tmp_slot->status))
                        return 0;
                i++;
        }
        return 1;
}

/***********************************************************
 * If the HPC permits and the bus currently empty, tries to set the
 * bus speed and mode at the maximum card and bus capability
 * Parameters: slot
 * Returns: bus is set (0) or error code
 ***********************************************************/
static int set_bus(struct slot *slot_cur)
{
        int rc;
        u8 speed;
        u8 cmd = 0x0;
        int retval;
        static const struct pci_device_id ciobx[] = {
                { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, 0x0101) },
                { },
        };

        debug("%s - entry slot # %d\n", __func__, slot_cur->number);
        if (SET_BUS_STATUS(slot_cur->ctrl) && is_bus_empty(slot_cur)) {
                rc = slot_update(&slot_cur);
                if (rc)
                        return rc;
                speed = SLOT_SPEED(slot_cur->ext_status);
                debug("ext_status = %x, speed = %x\n", slot_cur->ext_status, speed);
                switch (speed) {
                case HPC_SLOT_SPEED_33:
                        cmd = HPC_BUS_33CONVMODE;
                        break;
                case HPC_SLOT_SPEED_66:
                        if (SLOT_PCIX(slot_cur->ext_status)) {
                                if ((slot_cur->supported_speed >= BUS_SPEED_66) &&
                                                (slot_cur->supported_bus_mode == BUS_MODE_PCIX))
                                        cmd = HPC_BUS_66PCIXMODE;
                                else if (!SLOT_BUS_MODE(slot_cur->ext_status))
                                        /* if max slot/bus capability is 66 pci
                                        and there's no bus mode mismatch, then
                                        the adapter supports 66 pci */
                                        cmd = HPC_BUS_66CONVMODE;
                                else
                                        cmd = HPC_BUS_33CONVMODE;
                        } else {
                                if (slot_cur->supported_speed >= BUS_SPEED_66)
                                        cmd = HPC_BUS_66CONVMODE;
                                else
                                        cmd = HPC_BUS_33CONVMODE;
                        }
                        break;
                case HPC_SLOT_SPEED_133:
                        switch (slot_cur->supported_speed) {
                        case BUS_SPEED_33:
                                cmd = HPC_BUS_33CONVMODE;
                                break;
                        case BUS_SPEED_66:
                                if (slot_cur->supported_bus_mode == BUS_MODE_PCIX)
                                        cmd = HPC_BUS_66PCIXMODE;
                                else
                                        cmd = HPC_BUS_66CONVMODE;
                                break;
                        case BUS_SPEED_100:
                                cmd = HPC_BUS_100PCIXMODE;
                                break;
                        case BUS_SPEED_133:
                                /* This is to take care of the bug in CIOBX chip */
                                if (pci_dev_present(ciobx))
                                        ibmphp_hpc_writeslot(slot_cur,
                                                        HPC_BUS_100PCIXMODE);
                                cmd = HPC_BUS_133PCIXMODE;
                                break;
                        default:
                                err("Wrong bus speed\n");
                                return -ENODEV;
                        }
                        break;
                default:
                        err("wrong slot speed\n");
                        return -ENODEV;
                }
                debug("setting bus speed for slot %d, cmd %x\n",
                                                slot_cur->number, cmd);
                retval = ibmphp_hpc_writeslot(slot_cur, cmd);
                if (retval) {
                        err("setting bus speed failed\n");
                        return retval;
                }
                if (CTLR_RESULT(slot_cur->ctrl->status)) {
                        err("command not completed successfully in set_bus\n");
                        return -EIO;
                }
        }
        /* This is for x440, once Brandon fixes the firmware,
        will not need this delay */
        msleep(1000);
        debug("%s -Exit\n", __func__);
        return 0;
}

/* This routine checks the bus limitations that the slot is on from the BIOS.
 * This is used in deciding whether or not to power up the slot.
 * (electrical/spec limitations. For example, >1 133 MHz or >2 66 PCI cards on
 * same bus)
 * Parameters: slot
 * Returns: 0 = no limitations, -EINVAL = exceeded limitations on the bus
 */
static int check_limitations(struct slot *slot_cur)
{
        u8 i;
        struct slot *tmp_slot;
        u8 count = 0;
        u8 limitation = 0;

        for (i = slot_cur->bus_on->slot_min; i <= slot_cur->bus_on->slot_max; i++) {
                tmp_slot = ibmphp_get_slot_from_physical_num(i);
                if (!tmp_slot)
                        return -ENODEV;
                if ((SLOT_PWRGD(tmp_slot->status)) &&
                                        !(SLOT_CONNECT(tmp_slot->status)))
                        count++;
        }
        get_cur_bus_info(&slot_cur);
        switch (slot_cur->bus_on->current_speed) {
        case BUS_SPEED_33:
                limitation = slot_cur->bus_on->slots_at_33_conv;
                break;
        case BUS_SPEED_66:
                if (slot_cur->bus_on->current_bus_mode == BUS_MODE_PCIX)
                        limitation = slot_cur->bus_on->slots_at_66_pcix;
                else
                        limitation = slot_cur->bus_on->slots_at_66_conv;
                break;
        case BUS_SPEED_100:
                limitation = slot_cur->bus_on->slots_at_100_pcix;
                break;
        case BUS_SPEED_133:
                limitation = slot_cur->bus_on->slots_at_133_pcix;
                break;
        }

        if ((count + 1) > limitation)
                return -EINVAL;
        return 0;
}

static inline void print_card_capability(struct slot *slot_cur)
{
        info("capability of the card is ");
        if ((slot_cur->ext_status & CARD_INFO) == PCIX133)
                info("   133 MHz PCI-X\n");
        else if ((slot_cur->ext_status & CARD_INFO) == PCIX66)
                info("    66 MHz PCI-X\n");
        else if ((slot_cur->ext_status & CARD_INFO) == PCI66)
                info("    66 MHz PCI\n");
        else
                info("    33 MHz PCI\n");

}

/* This routine will power on the slot, configure the device(s) and find the
 * drivers for them.
 * Parameters: hotplug_slot
 * Returns: 0 or failure codes
 */
static int enable_slot(struct hotplug_slot *hs)
{
        int rc, i, rcpr;
        struct slot *slot_cur;
        u8 function;
        struct pci_func *tmp_func;

        ibmphp_lock_operations();

        debug("ENABLING SLOT........\n");
        slot_cur = to_slot(hs);

        rc = validate(slot_cur, ENABLE);
        if (rc) {
                err("validate function failed\n");
                goto error_nopower;
        }

        attn_LED_blink(slot_cur);

        rc = set_bus(slot_cur);
        if (rc) {
                err("was not able to set the bus\n");
                goto error_nopower;
        }

        /*-----------------debugging------------------------------*/
        get_cur_bus_info(&slot_cur);
        debug("the current bus speed right after set_bus = %x\n",
                                        slot_cur->bus_on->current_speed);
        /*----------------------------------------------------------*/

        rc = check_limitations(slot_cur);
        if (rc) {
                err("Adding this card exceeds the limitations of this bus.\n");
                err("(i.e., >1 133MHz cards running on same bus, or >2 66 PCI cards running on same bus.\n");
                err("Try hot-adding into another bus\n");

                rc = -EINVAL;
                goto error_nopower;
        }

        rc = power_on(slot_cur);

        if (rc) {
                err("something wrong when powering up... please see below for details\n");
                /* need to turn off before on, otherwise, blinking overwrites */
                attn_off(slot_cur);
                attn_on(slot_cur);
                if (slot_update(&slot_cur)) {
                        attn_off(slot_cur);
                        attn_on(slot_cur);
                        rc = -ENODEV;
                        goto exit;
                }
                /* Check to see the error of why it failed */
                if ((SLOT_POWER(slot_cur->status)) &&
                                        !(SLOT_PWRGD(slot_cur->status)))
                        err("power fault occurred trying to power up\n");
                else if (SLOT_BUS_SPEED(slot_cur->status)) {
                        err("bus speed mismatch occurred.  please check current bus speed and card capability\n");
                        print_card_capability(slot_cur);
                } else if (SLOT_BUS_MODE(slot_cur->ext_status)) {
                        err("bus mode mismatch occurred.  please check current bus mode and card capability\n");
                        print_card_capability(slot_cur);
                }
                ibmphp_update_slot_info(slot_cur);
                goto exit;
        }
        debug("after power_on\n");
        /*-----------------------debugging---------------------------*/
        get_cur_bus_info(&slot_cur);
        debug("the current bus speed right after power_on = %x\n",
                                        slot_cur->bus_on->current_speed);
        /*----------------------------------------------------------*/

        rc = slot_update(&slot_cur);
        if (rc)
                goto error_power;

        rc = -EINVAL;
        if (SLOT_POWER(slot_cur->status) && !(SLOT_PWRGD(slot_cur->status))) {
                err("power fault occurred trying to power up...\n");
                goto error_power;
        }
        if (SLOT_POWER(slot_cur->status) && (SLOT_BUS_SPEED(slot_cur->status))) {
                err("bus speed mismatch occurred.  please check current bus speed and card capability\n");
                print_card_capability(slot_cur);
                goto error_power;
        }
        /* Don't think this case will happen after above checks...
         * but just in case, for paranoia sake */
        if (!(SLOT_POWER(slot_cur->status))) {
                err("power on failed...\n");
                goto error_power;
        }

        slot_cur->func = kzalloc(sizeof(struct pci_func), GFP_KERNEL);
        if (!slot_cur->func) {
                /* do update_slot_info here? */
                rc = -ENOMEM;
                goto error_power;
        }
        slot_cur->func->busno = slot_cur->bus;
        slot_cur->func->device = slot_cur->device;
        for (i = 0; i < 4; i++)
                slot_cur->func->irq[i] = slot_cur->irq[i];

        debug("b4 configure_card, slot_cur->bus = %x, slot_cur->device = %x\n",
                                        slot_cur->bus, slot_cur->device);

        if (ibmphp_configure_card(slot_cur->func, slot_cur->number)) {
                err("configure_card was unsuccessful...\n");
                /* true because don't need to actually deallocate resources,
                 * just remove references */
                ibmphp_unconfigure_card(&slot_cur, 1);
                debug("after unconfigure_card\n");
                slot_cur->func = NULL;
                rc = -ENOMEM;
                goto error_power;
        }

        function = 0x00;
        do {
                tmp_func = ibm_slot_find(slot_cur->bus, slot_cur->func->device,
                                                        function++);
                if (tmp_func && !(tmp_func->dev))
                        ibm_configure_device(tmp_func);
        } while (tmp_func);

        attn_off(slot_cur);
        if (slot_update(&slot_cur)) {
                rc = -EFAULT;
                goto exit;
        }
        ibmphp_print_test();
        rc = ibmphp_update_slot_info(slot_cur);
exit:
        ibmphp_unlock_operations();
        return rc;

error_nopower:
        attn_off(slot_cur);     /* need to turn off if was blinking b4 */
        attn_on(slot_cur);
error_cont:
        rcpr = slot_update(&slot_cur);
        if (rcpr) {
                rc = rcpr;
                goto exit;
        }
        ibmphp_update_slot_info(slot_cur);
        goto exit;

error_power:
        attn_off(slot_cur);     /* need to turn off if was blinking b4 */
        attn_on(slot_cur);
        rcpr = power_off(slot_cur);
        if (rcpr) {
                rc = rcpr;
                goto exit;
        }
        goto error_cont;
}

/**************************************************************
* HOT REMOVING ADAPTER CARD                                   *
* INPUT: POINTER TO THE HOTPLUG SLOT STRUCTURE                *
* OUTPUT: SUCCESS 0 ; FAILURE: UNCONFIGURE , VALIDATE         *
*               DISABLE POWER ,                               *
**************************************************************/
static int ibmphp_disable_slot(struct hotplug_slot *hotplug_slot)
{
        struct slot *slot = to_slot(hotplug_slot);
        int rc;

        ibmphp_lock_operations();
        rc = ibmphp_do_disable_slot(slot);
        ibmphp_unlock_operations();
        return rc;
}

int ibmphp_do_disable_slot(struct slot *slot_cur)
{
        int rc;
        u8 flag;

        debug("DISABLING SLOT...\n");

        if ((slot_cur == NULL) || (slot_cur->ctrl == NULL))
                return -ENODEV;

        flag = slot_cur->flag;
        slot_cur->flag = 1;

        if (flag == 1) {
                rc = validate(slot_cur, DISABLE);
                        /* checking if powered off already & valid slot # */
                if (rc)
                        goto error;
        }
        attn_LED_blink(slot_cur);

        if (slot_cur->func == NULL) {
                /* We need this for functions that were there on bootup */
                slot_cur->func = kzalloc(sizeof(struct pci_func), GFP_KERNEL);
                if (!slot_cur->func) {
                        rc = -ENOMEM;
                        goto error;
                }
                slot_cur->func->busno = slot_cur->bus;
                slot_cur->func->device = slot_cur->device;
        }

        ibm_unconfigure_device(slot_cur->func);

        /*
         * If we got here from latch suddenly opening on operating card or
         * a power fault, there's no power to the card, so cannot
         * read from it to determine what resources it occupied.  This operation
         * is forbidden anyhow.  The best we can do is remove it from kernel
         * lists at least */

        if (!flag) {
                attn_off(slot_cur);
                return 0;
        }

        rc = ibmphp_unconfigure_card(&slot_cur, 0);
        slot_cur->func = NULL;
        debug("in disable_slot. after unconfigure_card\n");
        if (rc) {
                err("could not unconfigure card.\n");
                goto error;
        }

        rc = ibmphp_hpc_writeslot(slot_cur, HPC_SLOT_OFF);
        if (rc)
                goto error;

        attn_off(slot_cur);
        rc = slot_update(&slot_cur);
        if (rc)
                goto exit;

        rc = ibmphp_update_slot_info(slot_cur);
        ibmphp_print_test();
exit:
        return rc;

error:
        /*  Need to turn off if was blinking b4 */
        attn_off(slot_cur);
        attn_on(slot_cur);
        if (slot_update(&slot_cur)) {
                rc = -EFAULT;
                goto exit;
        }
        if (flag)
                ibmphp_update_slot_info(slot_cur);
        goto exit;
}

const struct hotplug_slot_ops ibmphp_hotplug_slot_ops = {
        .set_attention_status =         set_attention_status,
        .enable_slot =                  enable_slot,
        .disable_slot =                 ibmphp_disable_slot,
        .hardware_test =                NULL,
        .get_power_status =             get_power_status,
        .get_attention_status =         get_attention_status,
        .get_latch_status =             get_latch_status,
        .get_adapter_status =           get_adapter_present,
/*      .get_max_adapter_speed =        get_max_adapter_speed,
        .get_bus_name_status =          get_bus_name,
*/
};

static void ibmphp_unload(void)
{
        free_slots();
        debug("after slots\n");
        ibmphp_free_resources();
        debug("after resources\n");
        ibmphp_free_bus_info_queue();
        debug("after bus info\n");
        ibmphp_free_ebda_hpc_queue();
        debug("after ebda hpc\n");
        ibmphp_free_ebda_pci_rsrc_queue();
        debug("after ebda pci rsrc\n");
        kfree(ibmphp_pci_bus);
}

static int __init ibmphp_init(void)
{
        struct pci_bus *bus;
        int i = 0;
        int rc = 0;

        init_flag = 1;

        info(DRIVER_DESC " version: " DRIVER_VERSION "\n");

        ibmphp_pci_bus = kmalloc(sizeof(*ibmphp_pci_bus), GFP_KERNEL);
        if (!ibmphp_pci_bus) {
                rc = -ENOMEM;
                goto exit;
        }

        bus = pci_find_bus(0, 0);
        if (!bus) {
                err("Can't find the root pci bus, can not continue\n");
                rc = -ENODEV;
                goto error;
        }
        memcpy(ibmphp_pci_bus, bus, sizeof(*ibmphp_pci_bus));

        ibmphp_debug = debug;

        for (i = 0; i < 16; i++)
                irqs[i] = 0;

        rc = ibmphp_access_ebda();
        if (rc)
                goto error;
        debug("after ibmphp_access_ebda()\n");

        rc = ibmphp_rsrc_init();
        if (rc)
                goto error;
        debug("AFTER Resource & EBDA INITIALIZATIONS\n");

        max_slots = get_max_slots();

        rc = ibmphp_register_pci();
        if (rc)
                goto error;

        if (init_ops()) {
                rc = -ENODEV;
                goto error;
        }

        ibmphp_print_test();
        rc = ibmphp_hpc_start_poll_thread();
        if (rc)
                goto error;

exit:
        return rc;

error:
        ibmphp_unload();
        goto exit;
}

static void __exit ibmphp_exit(void)
{
        ibmphp_hpc_stop_poll_thread();
        debug("after polling\n");
        ibmphp_unload();
        debug("done\n");
}

module_init(ibmphp_init);
module_exit(ibmphp_exit);