/*
 * Copyright(c) 2015, 2016 Intel Corporation.
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License 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.
 *
 * BSD LICENSE
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  - Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  - Neither the name of Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/bitmap.h>

#include "hfi.h"
#include "common.h"
#include "sdma.h"

#define LINK_UP_DELAY  500  /* in microseconds */

static void set_mgmt_allowed(struct hfi1_pportdata *ppd)
{
        u32 frame;
        struct hfi1_devdata *dd = ppd->dd;

        if (ppd->neighbor_type == NEIGHBOR_TYPE_HFI) {
                ppd->mgmt_allowed = 1;
        } else {
                read_8051_config(dd, REMOTE_LNI_INFO, GENERAL_CONFIG, &frame);
                ppd->mgmt_allowed = (frame >> MGMT_ALLOWED_SHIFT)
                & MGMT_ALLOWED_MASK;
        }
}

/*
 * Our neighbor has indicated that we are allowed to act as a fabric
 * manager, so place the full management partition key in the second
 * (0-based) pkey array position. Note that we should already have
 * the limited management partition key in array element 1, and also
 * that the port is not yet up when add_full_mgmt_pkey() is invoked.
 */
static void add_full_mgmt_pkey(struct hfi1_pportdata *ppd)
{
        struct hfi1_devdata *dd = ppd->dd;

        /* Sanity check - ppd->pkeys[2] should be 0, or already initialized */
        if (!((ppd->pkeys[2] == 0) || (ppd->pkeys[2] == FULL_MGMT_P_KEY)))
                dd_dev_warn(dd, "%s pkey[2] already set to 0x%x, resetting it to 0x%x\n",
                            __func__, ppd->pkeys[2], FULL_MGMT_P_KEY);
        ppd->pkeys[2] = FULL_MGMT_P_KEY;
        (void)hfi1_set_ib_cfg(ppd, HFI1_IB_CFG_PKEYS, 0);
        hfi1_event_pkey_change(ppd->dd, ppd->port);
}

/**
 * format_hwmsg - format a single hwerror message
 * @msg message buffer
 * @msgl length of message buffer
 * @hwmsg message to add to message buffer
 */
static void format_hwmsg(char *msg, size_t msgl, const char *hwmsg)
{
        strlcat(msg, "[", msgl);
        strlcat(msg, hwmsg, msgl);
        strlcat(msg, "]", msgl);
}

/**
 * hfi1_format_hwerrors - format hardware error messages for display
 * @hwerrs hardware errors bit vector
 * @hwerrmsgs hardware error descriptions
 * @nhwerrmsgs number of hwerrmsgs
 * @msg message buffer
 * @msgl message buffer length
 */
void hfi1_format_hwerrors(u64 hwerrs, const struct hfi1_hwerror_msgs *hwerrmsgs,
                          size_t nhwerrmsgs, char *msg, size_t msgl)
{
        int i;

        for (i = 0; i < nhwerrmsgs; i++)
                if (hwerrs & hwerrmsgs[i].mask)
                        format_hwmsg(msg, msgl, hwerrmsgs[i].msg);
}

static void signal_ib_event(struct hfi1_pportdata *ppd, enum ib_event_type ev)
{
        struct ib_event event;
        struct hfi1_devdata *dd = ppd->dd;

        /*
         * Only call ib_dispatch_event() if the IB device has been
         * registered.  HFI1_INITED is set iff the driver has successfully
         * registered with the IB core.
         */
        if (!(dd->flags & HFI1_INITTED))
                return;
        event.device = &dd->verbs_dev.rdi.ibdev;
        event.element.port_num = ppd->port;
        event.event = ev;
        ib_dispatch_event(&event);
}

/**
 * handle_linkup_change - finish linkup/down state changes
 * @dd: valid device
 * @linkup: link state information
 *
 * Handle a linkup or link down notification.
 * The HW needs time to finish its link up state change. Give it that chance.
 *
 * This is called outside an interrupt.
 *
 */
void handle_linkup_change(struct hfi1_devdata *dd, u32 linkup)
{
        struct hfi1_pportdata *ppd = &dd->pport[0];
        enum ib_event_type ev;

        if (!(ppd->linkup ^ !!linkup))
                return; /* no change, nothing to do */

        if (linkup) {
                /*
                 * Quick linkup and all link up on the simulator does not
                 * trigger or implement:
                 *      - VerifyCap interrupt
                 *      - VerifyCap frames
                 * But rather moves directly to LinkUp.
                 *
                 * Do the work of the VerifyCap interrupt handler,
                 * handle_verify_cap(), but do not try moving the state to
                 * LinkUp as we are already there.
                 *
                 * NOTE: This uses this device's vAU, vCU, and vl15_init for
                 * the remote values.  Both sides must be using the values.
                 */
                if (quick_linkup || dd->icode == ICODE_FUNCTIONAL_SIMULATOR) {
                        set_up_vau(dd, dd->vau);
                        set_up_vl15(dd, dd->vl15_init);
                        assign_remote_cm_au_table(dd, dd->vcu);
                }

                ppd->neighbor_guid =
                        read_csr(dd, DC_DC8051_STS_REMOTE_GUID);
                ppd->neighbor_type =
                        read_csr(dd, DC_DC8051_STS_REMOTE_NODE_TYPE) &
                                 DC_DC8051_STS_REMOTE_NODE_TYPE_VAL_MASK;
                ppd->neighbor_port_number =
                        read_csr(dd, DC_DC8051_STS_REMOTE_PORT_NO) &
                                 DC_DC8051_STS_REMOTE_PORT_NO_VAL_SMASK;
                ppd->neighbor_fm_security =
                        read_csr(dd, DC_DC8051_STS_REMOTE_FM_SECURITY) &
                                 DC_DC8051_STS_LOCAL_FM_SECURITY_DISABLED_MASK;
                dd_dev_info(dd,
                            "Neighbor Guid %llx, Type %d, Port Num %d\n",
                            ppd->neighbor_guid, ppd->neighbor_type,
                            ppd->neighbor_port_number);

                /* HW needs LINK_UP_DELAY to settle, give it that chance */
                udelay(LINK_UP_DELAY);

                /*
                 * 'MgmtAllowed' information, which is exchanged during
                 * LNI, is available at this point.
                 */
                set_mgmt_allowed(ppd);

                if (ppd->mgmt_allowed)
                        add_full_mgmt_pkey(ppd);

                /* physical link went up */
                ppd->linkup = 1;
                ppd->offline_disabled_reason =
                        HFI1_ODR_MASK(OPA_LINKDOWN_REASON_NONE);

                /* link widths are not available until the link is fully up */
                get_linkup_link_widths(ppd);

        } else {
                /* physical link went down */
                ppd->linkup = 0;

                /* clear HW details of the previous connection */
                ppd->actual_vls_operational = 0;
                reset_link_credits(dd);

                /* freeze after a link down to guarantee a clean egress */
                start_freeze_handling(ppd, FREEZE_SELF | FREEZE_LINK_DOWN);

                ev = IB_EVENT_PORT_ERR;

                hfi1_set_uevent_bits(ppd, _HFI1_EVENT_LINKDOWN_BIT);

                /* if we are down, the neighbor is down */
                ppd->neighbor_normal = 0;

                /* notify IB of the link change */
                signal_ib_event(ppd, ev);
        }
}

/*
 * Handle receive or urgent interrupts for user contexts.  This means a user
 * process was waiting for a packet to arrive, and didn't want to poll.
 */
void handle_user_interrupt(struct hfi1_ctxtdata *rcd)
{
        struct hfi1_devdata *dd = rcd->dd;
        unsigned long flags;

        spin_lock_irqsave(&dd->uctxt_lock, flags);
        if (bitmap_empty(rcd->in_use_ctxts, HFI1_MAX_SHARED_CTXTS))
                goto done;

        if (test_and_clear_bit(HFI1_CTXT_WAITING_RCV, &rcd->event_flags)) {
                wake_up_interruptible(&rcd->wait);
                hfi1_rcvctrl(dd, HFI1_RCVCTRL_INTRAVAIL_DIS, rcd);
        } else if (test_and_clear_bit(HFI1_CTXT_WAITING_URG,
                                                        &rcd->event_flags)) {
                rcd->urgent++;
                wake_up_interruptible(&rcd->wait);
        }
done:
        spin_unlock_irqrestore(&dd->uctxt_lock, flags);
}