/*
 * Copyright 2013 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Dave Airlie
 *          Alon Levy
 */

#include <linux/pci.h>

#include <drm/drm_drv.h>
#include <drm/drm_print.h>

#include "qxl_drv.h"

static irqreturn_t qxl_irq_handler(int irq, void *arg)
{
        struct drm_device *dev = (struct drm_device *) arg;
        struct qxl_device *qdev = to_qxl(dev);
        uint32_t pending;

        pending = xchg(&qdev->ram_header->int_pending, 0);

        if (!pending)
                return IRQ_NONE;

        atomic_inc(&qdev->irq_received);

        if (pending & QXL_INTERRUPT_DISPLAY) {
                atomic_inc(&qdev->irq_received_display);
                wake_up_all(&qdev->display_event);
                qxl_queue_garbage_collect(qdev, false);
        }
        if (pending & QXL_INTERRUPT_CURSOR) {
                atomic_inc(&qdev->irq_received_cursor);
                wake_up_all(&qdev->cursor_event);
        }
        if (pending & QXL_INTERRUPT_IO_CMD) {
                atomic_inc(&qdev->irq_received_io_cmd);
                wake_up_all(&qdev->io_cmd_event);
        }
        if (pending & QXL_INTERRUPT_ERROR) {
                /* TODO: log it, reset device (only way to exit this condition)
                 * (do it a certain number of times, afterwards admit defeat,
                 * to avoid endless loops).
                 */
                qdev->irq_received_error++;
                DRM_WARN("driver is in bug mode\n");
        }
        if (pending & QXL_INTERRUPT_CLIENT_MONITORS_CONFIG) {
                schedule_work(&qdev->client_monitors_config_work);
        }
        qdev->ram_header->int_mask = QXL_INTERRUPT_MASK;
        outb(0, qdev->io_base + QXL_IO_UPDATE_IRQ);
        return IRQ_HANDLED;
}

static void qxl_client_monitors_config_work_func(struct work_struct *work)
{
        struct qxl_device *qdev = container_of(work, struct qxl_device,
                                               client_monitors_config_work);

        qxl_display_read_client_monitors_config(qdev);
}

int qxl_irq_init(struct qxl_device *qdev)
{
        struct drm_device *ddev = &qdev->ddev;
        struct pci_dev *pdev = to_pci_dev(ddev->dev);
        int ret;

        init_waitqueue_head(&qdev->display_event);
        init_waitqueue_head(&qdev->cursor_event);
        init_waitqueue_head(&qdev->io_cmd_event);
        init_waitqueue_head(&qdev->release_event);
        INIT_WORK(&qdev->client_monitors_config_work,
                  qxl_client_monitors_config_work_func);
        atomic_set(&qdev->irq_received, 0);
        atomic_set(&qdev->irq_received_display, 0);
        atomic_set(&qdev->irq_received_cursor, 0);
        atomic_set(&qdev->irq_received_io_cmd, 0);
        qdev->irq_received_error = 0;
        ret = request_irq(pdev->irq, qxl_irq_handler, IRQF_SHARED, ddev->driver->name, ddev);
        qdev->ram_header->int_mask = QXL_INTERRUPT_MASK;
        if (unlikely(ret != 0)) {
                DRM_ERROR("Failed installing irq: %d\n", ret);
                return 1;
        }
        return 0;
}