/*
 * drivers/gpu/drm/omapdrm/omap_crtc.c
 *
 * Copyright (C) 2011 Texas Instruments
 * Author: Rob Clark <rob@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 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.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "omap_drv.h"

#include <drm/drm_mode.h>
#include "drm_crtc.h"
#include "drm_crtc_helper.h"

#define to_omap_crtc(x) container_of(x, struct omap_crtc, base)

struct omap_crtc {
        struct drm_crtc base;
        struct drm_plane *plane;

        const char *name;
        int pipe;
        enum omap_channel channel;
        struct omap_overlay_manager_info info;

        /*
         * Temporary: eventually this will go away, but it is needed
         * for now to keep the output's happy.  (They only need
         * mgr->id.)  Eventually this will be replaced w/ something
         * more common-panel-framework-y
         */
        struct omap_overlay_manager *mgr;

        struct omap_video_timings timings;
        bool enabled;
        bool full_update;

        struct omap_drm_apply apply;

        struct omap_drm_irq apply_irq;
        struct omap_drm_irq error_irq;

        /* list of in-progress apply's: */
        struct list_head pending_applies;

        /* list of queued apply's: */
        struct list_head queued_applies;

        /* for handling queued and in-progress applies: */
        struct work_struct apply_work;

        /* if there is a pending flip, these will be non-null: */
        struct drm_pending_vblank_event *event;
        struct drm_framebuffer *old_fb;

        /* for handling page flips without caring about what
         * the callback is called from.  Possibly we should just
         * make omap_gem always call the cb from the worker so
         * we don't have to care about this..
         *
         * XXX maybe fold into apply_work??
         */
        struct work_struct page_flip_work;
};

uint32_t pipe2vbl(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);

        return dispc_mgr_get_vsync_irq(omap_crtc->channel);
}

/*
 * Manager-ops, callbacks from output when they need to configure
 * the upstream part of the video pipe.
 *
 * Most of these we can ignore until we add support for command-mode
 * panels.. for video-mode the crtc-helpers already do an adequate
 * job of sequencing the setup of the video pipe in the proper order
 */

/* ovl-mgr-id -> crtc */
static struct omap_crtc *omap_crtcs[8];

/* we can probably ignore these until we support command-mode panels: */
static int omap_crtc_connect(struct omap_overlay_manager *mgr,
                struct omap_dss_device *dst)
{
        if (mgr->output)
                return -EINVAL;

        if ((mgr->supported_outputs & dst->id) == 0)
                return -EINVAL;

        dst->manager = mgr;
        mgr->output = dst;

        return 0;
}

static void omap_crtc_disconnect(struct omap_overlay_manager *mgr,
                struct omap_dss_device *dst)
{
        mgr->output->manager = NULL;
        mgr->output = NULL;
}

static void omap_crtc_start_update(struct omap_overlay_manager *mgr)
{
}

static int omap_crtc_enable(struct omap_overlay_manager *mgr)
{
        return 0;
}

static void omap_crtc_disable(struct omap_overlay_manager *mgr)
{
}

static void omap_crtc_set_timings(struct omap_overlay_manager *mgr,
                const struct omap_video_timings *timings)
{
        struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
        DBG("%s", omap_crtc->name);
        omap_crtc->timings = *timings;
        omap_crtc->full_update = true;
}

static void omap_crtc_set_lcd_config(struct omap_overlay_manager *mgr,
                const struct dss_lcd_mgr_config *config)
{
        struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
        DBG("%s", omap_crtc->name);
        dispc_mgr_set_lcd_config(omap_crtc->channel, config);
}

static int omap_crtc_register_framedone_handler(
                struct omap_overlay_manager *mgr,
                void (*handler)(void *), void *data)
{
        return 0;
}

static void omap_crtc_unregister_framedone_handler(
                struct omap_overlay_manager *mgr,
                void (*handler)(void *), void *data)
{
}

static const struct dss_mgr_ops mgr_ops = {
                .connect = omap_crtc_connect,
                .disconnect = omap_crtc_disconnect,
                .start_update = omap_crtc_start_update,
                .enable = omap_crtc_enable,
                .disable = omap_crtc_disable,
                .set_timings = omap_crtc_set_timings,
                .set_lcd_config = omap_crtc_set_lcd_config,
                .register_framedone_handler = omap_crtc_register_framedone_handler,
                .unregister_framedone_handler = omap_crtc_unregister_framedone_handler,
};

/*
 * CRTC funcs:
 */

static void omap_crtc_destroy(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);

        DBG("%s", omap_crtc->name);

        WARN_ON(omap_crtc->apply_irq.registered);
        omap_irq_unregister(crtc->dev, &omap_crtc->error_irq);

        omap_crtc->plane->funcs->destroy(omap_crtc->plane);
        drm_crtc_cleanup(crtc);

        kfree(omap_crtc);
}

static void omap_crtc_dpms(struct drm_crtc *crtc, int mode)
{
        struct omap_drm_private *priv = crtc->dev->dev_private;
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        bool enabled = (mode == DRM_MODE_DPMS_ON);
        int i;

        DBG("%s: %d", omap_crtc->name, mode);

        if (enabled != omap_crtc->enabled) {
                omap_crtc->enabled = enabled;
                omap_crtc->full_update = true;
                omap_crtc_apply(crtc, &omap_crtc->apply);

                /* also enable our private plane: */
                WARN_ON(omap_plane_dpms(omap_crtc->plane, mode));

                /* and any attached overlay planes: */
                for (i = 0; i < priv->num_planes; i++) {
                        struct drm_plane *plane = priv->planes[i];
                        if (plane->crtc == crtc)
                                WARN_ON(omap_plane_dpms(plane, mode));
                }
        }
}

static bool omap_crtc_mode_fixup(struct drm_crtc *crtc,
                const struct drm_display_mode *mode,
                struct drm_display_mode *adjusted_mode)
{
        return true;
}

static int omap_crtc_mode_set(struct drm_crtc *crtc,
                struct drm_display_mode *mode,
                struct drm_display_mode *adjusted_mode,
                int x, int y,
                struct drm_framebuffer *old_fb)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);

        mode = adjusted_mode;

        DBG("%s: set mode: %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x",
                        omap_crtc->name, mode->base.id, mode->name,
                        mode->vrefresh, mode->clock,
                        mode->hdisplay, mode->hsync_start,
                        mode->hsync_end, mode->htotal,
                        mode->vdisplay, mode->vsync_start,
                        mode->vsync_end, mode->vtotal,
                        mode->type, mode->flags);

        copy_timings_drm_to_omap(&omap_crtc->timings, mode);
        omap_crtc->full_update = true;

        return omap_plane_mode_set(omap_crtc->plane, crtc, crtc->fb,
                        0, 0, mode->hdisplay, mode->vdisplay,
                        x << 16, y << 16,
                        mode->hdisplay << 16, mode->vdisplay << 16,
                        NULL, NULL);
}

static void omap_crtc_prepare(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        DBG("%s", omap_crtc->name);
        omap_crtc_dpms(crtc, DRM_MODE_DPMS_OFF);
}

static void omap_crtc_commit(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        DBG("%s", omap_crtc->name);
        omap_crtc_dpms(crtc, DRM_MODE_DPMS_ON);
}

static int omap_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
                struct drm_framebuffer *old_fb)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        struct drm_plane *plane = omap_crtc->plane;
        struct drm_display_mode *mode = &crtc->mode;

        return omap_plane_mode_set(plane, crtc, crtc->fb,
                        0, 0, mode->hdisplay, mode->vdisplay,
                        x << 16, y << 16,
                        mode->hdisplay << 16, mode->vdisplay << 16,
                        NULL, NULL);
}

static void vblank_cb(void *arg)
{
        struct drm_crtc *crtc = arg;
        struct drm_device *dev = crtc->dev;
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        unsigned long flags;

        spin_lock_irqsave(&dev->event_lock, flags);

        /* wakeup userspace */
        if (omap_crtc->event)
                drm_send_vblank_event(dev, omap_crtc->pipe, omap_crtc->event);

        omap_crtc->event = NULL;
        omap_crtc->old_fb = NULL;

        spin_unlock_irqrestore(&dev->event_lock, flags);
}

static void page_flip_worker(struct work_struct *work)
{
        struct omap_crtc *omap_crtc =
                        container_of(work, struct omap_crtc, page_flip_work);
        struct drm_crtc *crtc = &omap_crtc->base;
        struct drm_display_mode *mode = &crtc->mode;
        struct drm_gem_object *bo;

        mutex_lock(&crtc->mutex);
        omap_plane_mode_set(omap_crtc->plane, crtc, crtc->fb,
                        0, 0, mode->hdisplay, mode->vdisplay,
                        crtc->x << 16, crtc->y << 16,
                        mode->hdisplay << 16, mode->vdisplay << 16,
                        vblank_cb, crtc);
        mutex_unlock(&crtc->mutex);

        bo = omap_framebuffer_bo(crtc->fb, 0);
        drm_gem_object_unreference_unlocked(bo);
}

static void page_flip_cb(void *arg)
{
        struct drm_crtc *crtc = arg;
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        struct omap_drm_private *priv = crtc->dev->dev_private;

        /* avoid assumptions about what ctxt we are called from: */
        queue_work(priv->wq, &omap_crtc->page_flip_work);
}

static int omap_crtc_page_flip_locked(struct drm_crtc *crtc,
                 struct drm_framebuffer *fb,
                 struct drm_pending_vblank_event *event,
                 uint32_t page_flip_flags)
{
        struct drm_device *dev = crtc->dev;
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        struct drm_gem_object *bo;

        DBG("%d -> %d (event=%p)", crtc->fb ? crtc->fb->base.id : -1,
                        fb->base.id, event);

        if (omap_crtc->old_fb) {
                dev_err(dev->dev, "already a pending flip\n");
                return -EINVAL;
        }

        omap_crtc->event = event;
        crtc->fb = fb;

        /*
         * Hold a reference temporarily until the crtc is updated
         * and takes the reference to the bo.  This avoids it
         * getting freed from under us:
         */
        bo = omap_framebuffer_bo(fb, 0);
        drm_gem_object_reference(bo);

        omap_gem_op_async(bo, OMAP_GEM_READ, page_flip_cb, crtc);

        return 0;
}

static int omap_crtc_set_property(struct drm_crtc *crtc,
                struct drm_property *property, uint64_t val)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        struct omap_drm_private *priv = crtc->dev->dev_private;

        if (property == priv->rotation_prop) {
                crtc->invert_dimensions =
                                !!(val & ((1LL << DRM_ROTATE_90) | (1LL << DRM_ROTATE_270)));
        }

        return omap_plane_set_property(omap_crtc->plane, property, val);
}

static const struct drm_crtc_funcs omap_crtc_funcs = {
        .set_config = drm_crtc_helper_set_config,
        .destroy = omap_crtc_destroy,
        .page_flip = omap_crtc_page_flip_locked,
        .set_property = omap_crtc_set_property,
};

static const struct drm_crtc_helper_funcs omap_crtc_helper_funcs = {
        .dpms = omap_crtc_dpms,
        .mode_fixup = omap_crtc_mode_fixup,
        .mode_set = omap_crtc_mode_set,
        .prepare = omap_crtc_prepare,
        .commit = omap_crtc_commit,
        .mode_set_base = omap_crtc_mode_set_base,
};

const struct omap_video_timings *omap_crtc_timings(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        return &omap_crtc->timings;
}

enum omap_channel omap_crtc_channel(struct drm_crtc *crtc)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        return omap_crtc->channel;
}

static void omap_crtc_error_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
{
        struct omap_crtc *omap_crtc =
                        container_of(irq, struct omap_crtc, error_irq);
        struct drm_crtc *crtc = &omap_crtc->base;
        DRM_ERROR("%s: errors: %08x\n", omap_crtc->name, irqstatus);
        /* avoid getting in a flood, unregister the irq until next vblank */
        __omap_irq_unregister(crtc->dev, &omap_crtc->error_irq);
}

static void omap_crtc_apply_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
{
        struct omap_crtc *omap_crtc =
                        container_of(irq, struct omap_crtc, apply_irq);
        struct drm_crtc *crtc = &omap_crtc->base;

        if (!omap_crtc->error_irq.registered)
                __omap_irq_register(crtc->dev, &omap_crtc->error_irq);

        if (!dispc_mgr_go_busy(omap_crtc->channel)) {
                struct omap_drm_private *priv =
                                crtc->dev->dev_private;
                DBG("%s: apply done", omap_crtc->name);
                __omap_irq_unregister(crtc->dev, &omap_crtc->apply_irq);
                queue_work(priv->wq, &omap_crtc->apply_work);
        }
}

static void apply_worker(struct work_struct *work)
{
        struct omap_crtc *omap_crtc =
                        container_of(work, struct omap_crtc, apply_work);
        struct drm_crtc *crtc = &omap_crtc->base;
        struct drm_device *dev = crtc->dev;
        struct omap_drm_apply *apply, *n;
        bool need_apply;

        /*
         * Synchronize everything on mode_config.mutex, to keep
         * the callbacks and list modification all serialized
         * with respect to modesetting ioctls from userspace.
         */
        mutex_lock(&crtc->mutex);
        dispc_runtime_get();

        /*
         * If we are still pending a previous update, wait.. when the
         * pending update completes, we get kicked again.
         */
        if (omap_crtc->apply_irq.registered)
                goto out;

        /* finish up previous apply's: */
        list_for_each_entry_safe(apply, n,
                        &omap_crtc->pending_applies, pending_node) {
                apply->post_apply(apply);
                list_del(&apply->pending_node);
        }

        need_apply = !list_empty(&omap_crtc->queued_applies);

        /* then handle the next round of of queued apply's: */
        list_for_each_entry_safe(apply, n,
                        &omap_crtc->queued_applies, queued_node) {
                apply->pre_apply(apply);
                list_del(&apply->queued_node);
                apply->queued = false;
                list_add_tail(&apply->pending_node,
                                &omap_crtc->pending_applies);
        }

        if (need_apply) {
                enum omap_channel channel = omap_crtc->channel;

                DBG("%s: GO", omap_crtc->name);

                if (dispc_mgr_is_enabled(channel)) {
                        omap_irq_register(dev, &omap_crtc->apply_irq);
                        dispc_mgr_go(channel);
                } else {
                        struct omap_drm_private *priv = dev->dev_private;
                        queue_work(priv->wq, &omap_crtc->apply_work);
                }
        }

out:
        dispc_runtime_put();
        mutex_unlock(&crtc->mutex);
}

int omap_crtc_apply(struct drm_crtc *crtc,
                struct omap_drm_apply *apply)
{
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);

        WARN_ON(!mutex_is_locked(&crtc->mutex));

        /* no need to queue it again if it is already queued: */
        if (apply->queued)
                return 0;

        apply->queued = true;
        list_add_tail(&apply->queued_node, &omap_crtc->queued_applies);

        /*
         * If there are no currently pending updates, then go ahead and
         * kick the worker immediately, otherwise it will run again when
         * the current update finishes.
         */
        if (list_empty(&omap_crtc->pending_applies)) {
                struct omap_drm_private *priv = crtc->dev->dev_private;
                queue_work(priv->wq, &omap_crtc->apply_work);
        }

        return 0;
}

/* called only from apply */
static void set_enabled(struct drm_crtc *crtc, bool enable)
{
        struct drm_device *dev = crtc->dev;
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
        enum omap_channel channel = omap_crtc->channel;
        struct omap_irq_wait *wait = NULL;

        if (dispc_mgr_is_enabled(channel) == enable)
                return;

        /* ignore sync-lost irqs during enable/disable */
        omap_irq_unregister(crtc->dev, &omap_crtc->error_irq);

        if (dispc_mgr_get_framedone_irq(channel)) {
                if (!enable) {
                        wait = omap_irq_wait_init(dev,
                                        dispc_mgr_get_framedone_irq(channel), 1);
                }
        } else {
                /*
                 * When we disable digit output, we need to wait until fields
                 * are done.  Otherwise the DSS is still working, and turning
                 * off the clocks prevents DSS from going to OFF mode. And when
                 * enabling, we need to wait for the extra sync losts
                 */
                wait = omap_irq_wait_init(dev,
                                dispc_mgr_get_vsync_irq(channel), 2);
        }

        dispc_mgr_enable(channel, enable);

        if (wait) {
                int ret = omap_irq_wait(dev, wait, msecs_to_jiffies(100));
                if (ret) {
                        dev_err(dev->dev, "%s: timeout waiting for %s\n",
                                        omap_crtc->name, enable ? "enable" : "disable");
                }
        }

        omap_irq_register(crtc->dev, &omap_crtc->error_irq);
}

static void omap_crtc_pre_apply(struct omap_drm_apply *apply)
{
        struct omap_crtc *omap_crtc =
                        container_of(apply, struct omap_crtc, apply);
        struct drm_crtc *crtc = &omap_crtc->base;
        struct drm_encoder *encoder = NULL;

        DBG("%s: enabled=%d, full=%d", omap_crtc->name,
                        omap_crtc->enabled, omap_crtc->full_update);

        if (omap_crtc->full_update) {
                struct omap_drm_private *priv = crtc->dev->dev_private;
                int i;
                for (i = 0; i < priv->num_encoders; i++) {
                        if (priv->encoders[i]->crtc == crtc) {
                                encoder = priv->encoders[i];
                                break;
                        }
                }
        }

        if (!omap_crtc->enabled) {
                set_enabled(&omap_crtc->base, false);
                if (encoder)
                        omap_encoder_set_enabled(encoder, false);
        } else {
                if (encoder) {
                        omap_encoder_set_enabled(encoder, false);
                        omap_encoder_update(encoder, omap_crtc->mgr,
                                        &omap_crtc->timings);
                        omap_encoder_set_enabled(encoder, true);
                        omap_crtc->full_update = false;
                }

                dispc_mgr_setup(omap_crtc->channel, &omap_crtc->info);
                dispc_mgr_set_timings(omap_crtc->channel,
                                &omap_crtc->timings);
                set_enabled(&omap_crtc->base, true);
        }

        omap_crtc->full_update = false;
}

static void omap_crtc_post_apply(struct omap_drm_apply *apply)
{
        /* nothing needed for post-apply */
}

static const char *channel_names[] = {
                [OMAP_DSS_CHANNEL_LCD] = "lcd",
                [OMAP_DSS_CHANNEL_DIGIT] = "tv",
                [OMAP_DSS_CHANNEL_LCD2] = "lcd2",
};

void omap_crtc_pre_init(void)
{
        dss_install_mgr_ops(&mgr_ops);
}

void omap_crtc_pre_uninit(void)
{
        dss_uninstall_mgr_ops();
}

/* initialize crtc */
struct drm_crtc *omap_crtc_init(struct drm_device *dev,
                struct drm_plane *plane, enum omap_channel channel, int id)
{
        struct drm_crtc *crtc = NULL;
        struct omap_crtc *omap_crtc;
        struct omap_overlay_manager_info *info;

        DBG("%s", channel_names[channel]);

        omap_crtc = kzalloc(sizeof(*omap_crtc), GFP_KERNEL);
        if (!omap_crtc)
                goto fail;

        crtc = &omap_crtc->base;

        INIT_WORK(&omap_crtc->page_flip_work, page_flip_worker);
        INIT_WORK(&omap_crtc->apply_work, apply_worker);

        INIT_LIST_HEAD(&omap_crtc->pending_applies);
        INIT_LIST_HEAD(&omap_crtc->queued_applies);

        omap_crtc->apply.pre_apply  = omap_crtc_pre_apply;
        omap_crtc->apply.post_apply = omap_crtc_post_apply;

        omap_crtc->channel = channel;
        omap_crtc->plane = plane;
        omap_crtc->plane->crtc = crtc;
        omap_crtc->name = channel_names[channel];
        omap_crtc->pipe = id;

        omap_crtc->apply_irq.irqmask = pipe2vbl(crtc);
        omap_crtc->apply_irq.irq = omap_crtc_apply_irq;

        omap_crtc->error_irq.irqmask =
                        dispc_mgr_get_sync_lost_irq(channel);
        omap_crtc->error_irq.irq = omap_crtc_error_irq;
        omap_irq_register(dev, &omap_crtc->error_irq);

        /* temporary: */
        omap_crtc->mgr = omap_dss_get_overlay_manager(channel);

        /* TODO: fix hard-coded setup.. add properties! */
        info = &omap_crtc->info;
        info->default_color = 0x00000000;
        info->trans_key = 0x00000000;
        info->trans_key_type = OMAP_DSS_COLOR_KEY_GFX_DST;
        info->trans_enabled = false;

        drm_crtc_init(dev, crtc, &omap_crtc_funcs);
        drm_crtc_helper_add(crtc, &omap_crtc_helper_funcs);

        omap_plane_install_properties(omap_crtc->plane, &crtc->base);

        omap_crtcs[channel] = omap_crtc;

        return crtc;

fail:
        if (crtc)
                omap_crtc_destroy(crtc);

        return NULL;
}