// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */


#include "msm_drv.h"
#include "mdp_kms.h"


struct mdp_irq_wait {
        struct mdp_irq irq;
        int count;
};

static DECLARE_WAIT_QUEUE_HEAD(wait_event);

static DEFINE_SPINLOCK(list_lock);

static void update_irq(struct mdp_kms *mdp_kms)
{
        struct mdp_irq *irq;
        uint32_t irqmask = mdp_kms->vblank_mask;

        assert_spin_locked(&list_lock);

        list_for_each_entry(irq, &mdp_kms->irq_list, node)
                irqmask |= irq->irqmask;

        mdp_kms->funcs->set_irqmask(mdp_kms, irqmask, mdp_kms->cur_irq_mask);
        mdp_kms->cur_irq_mask = irqmask;
}

/* if an mdp_irq's irqmask has changed, such as when mdp5 crtc<->encoder
 * link changes, this must be called to figure out the new global irqmask
 */
void mdp_irq_update(struct mdp_kms *mdp_kms)
{
        unsigned long flags;
        spin_lock_irqsave(&list_lock, flags);
        update_irq(mdp_kms);
        spin_unlock_irqrestore(&list_lock, flags);
}

void mdp_dispatch_irqs(struct mdp_kms *mdp_kms, uint32_t status)
{
        struct mdp_irq *handler, *n;
        unsigned long flags;

        spin_lock_irqsave(&list_lock, flags);
        mdp_kms->in_irq = true;
        list_for_each_entry_safe(handler, n, &mdp_kms->irq_list, node) {
                if (handler->irqmask & status) {
                        spin_unlock_irqrestore(&list_lock, flags);
                        handler->irq(handler, handler->irqmask & status);
                        spin_lock_irqsave(&list_lock, flags);
                }
        }
        mdp_kms->in_irq = false;
        update_irq(mdp_kms);
        spin_unlock_irqrestore(&list_lock, flags);

}

void mdp_update_vblank_mask(struct mdp_kms *mdp_kms, uint32_t mask, bool enable)
{
        unsigned long flags;

        spin_lock_irqsave(&list_lock, flags);
        if (enable)
                mdp_kms->vblank_mask |= mask;
        else
                mdp_kms->vblank_mask &= ~mask;
        update_irq(mdp_kms);
        spin_unlock_irqrestore(&list_lock, flags);
}

static void wait_irq(struct mdp_irq *irq, uint32_t irqstatus)
{
        struct mdp_irq_wait *wait =
                        container_of(irq, struct mdp_irq_wait, irq);
        wait->count--;
        wake_up_all(&wait_event);
}

void mdp_irq_wait(struct mdp_kms *mdp_kms, uint32_t irqmask)
{
        struct mdp_irq_wait wait = {
                .irq = {
                        .irq = wait_irq,
                        .irqmask = irqmask,
                },
                .count = 1,
        };
        mdp_irq_register(mdp_kms, &wait.irq);
        wait_event_timeout(wait_event, (wait.count <= 0),
                        msecs_to_jiffies(100));
        mdp_irq_unregister(mdp_kms, &wait.irq);
}

void mdp_irq_register(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
{
        unsigned long flags;
        bool needs_update = false;

        spin_lock_irqsave(&list_lock, flags);

        if (!irq->registered) {
                irq->registered = true;
                list_add(&irq->node, &mdp_kms->irq_list);
                needs_update = !mdp_kms->in_irq;
        }

        spin_unlock_irqrestore(&list_lock, flags);

        if (needs_update)
                mdp_irq_update(mdp_kms);
}

void mdp_irq_unregister(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
{
        unsigned long flags;
        bool needs_update = false;

        spin_lock_irqsave(&list_lock, flags);

        if (irq->registered) {
                irq->registered = false;
                list_del(&irq->node);
                needs_update = !mdp_kms->in_irq;
        }

        spin_unlock_irqrestore(&list_lock, flags);

        if (needs_update)
                mdp_irq_update(mdp_kms);
}