/*
 * Tegra host1x Channel
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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 <linux/host1x.h>
#include <linux/slab.h>

#include <trace/events/host1x.h>

#include "../channel.h"
#include "../dev.h"
#include "../intr.h"
#include "../job.h"

#define HOST1X_CHANNEL_SIZE 16384
#define TRACE_MAX_LENGTH 128U

static void trace_write_gather(struct host1x_cdma *cdma, struct host1x_bo *bo,
                               u32 offset, u32 words)
{
        struct device *dev = cdma_to_channel(cdma)->dev;
        void *mem = NULL;

        if (host1x_debug_trace_cmdbuf)
                mem = host1x_bo_mmap(bo);

        if (mem) {
                u32 i;
                /*
                 * Write in batches of 128 as there seems to be a limit
                 * of how much you can output to ftrace at once.
                 */
                for (i = 0; i < words; i += TRACE_MAX_LENGTH) {
                        u32 num_words = min(words - i, TRACE_MAX_LENGTH);

                        offset += i * sizeof(u32);

                        trace_host1x_cdma_push_gather(dev_name(dev), bo,
                                                      num_words, offset,
                                                      mem);
                }

                host1x_bo_munmap(bo, mem);
        }
}

static void submit_gathers(struct host1x_job *job)
{
        struct host1x_cdma *cdma = &job->channel->cdma;
        unsigned int i;

        for (i = 0; i < job->num_gathers; i++) {
                struct host1x_job_gather *g = &job->gathers[i];
                u32 op1 = host1x_opcode_gather(g->words);
                u32 op2 = g->base + g->offset;

                trace_write_gather(cdma, g->bo, g->offset, op1 & 0xffff);
                host1x_cdma_push(cdma, op1, op2);
        }
}

static inline void synchronize_syncpt_base(struct host1x_job *job)
{
        struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
        struct host1x_syncpt *sp = host->syncpt + job->syncpt_id;
        unsigned int id;
        u32 value;

        value = host1x_syncpt_read_max(sp);
        id = sp->base->id;

        host1x_cdma_push(&job->channel->cdma,
                         host1x_opcode_setclass(HOST1X_CLASS_HOST1X,
                                HOST1X_UCLASS_LOAD_SYNCPT_BASE, 1),
                         HOST1X_UCLASS_LOAD_SYNCPT_BASE_BASE_INDX_F(id) |
                         HOST1X_UCLASS_LOAD_SYNCPT_BASE_VALUE_F(value));
}

static int channel_submit(struct host1x_job *job)
{
        struct host1x_channel *ch = job->channel;
        struct host1x_syncpt *sp;
        u32 user_syncpt_incrs = job->syncpt_incrs;
        u32 prev_max = 0;
        u32 syncval;
        int err;
        struct host1x_waitlist *completed_waiter = NULL;
        struct host1x *host = dev_get_drvdata(ch->dev->parent);

        sp = host->syncpt + job->syncpt_id;
        trace_host1x_channel_submit(dev_name(ch->dev),
                                    job->num_gathers, job->num_relocs,
                                    job->syncpt_id, job->syncpt_incrs);

        /* before error checks, return current max */
        prev_max = job->syncpt_end = host1x_syncpt_read_max(sp);

        /* get submit lock */
        err = mutex_lock_interruptible(&ch->submitlock);
        if (err)
                goto error;

        completed_waiter = kzalloc(sizeof(*completed_waiter), GFP_KERNEL);
        if (!completed_waiter) {
                mutex_unlock(&ch->submitlock);
                err = -ENOMEM;
                goto error;
        }

        /* begin a CDMA submit */
        err = host1x_cdma_begin(&ch->cdma, job);
        if (err) {
                mutex_unlock(&ch->submitlock);
                goto error;
        }

        if (job->serialize) {
                /*
                 * Force serialization by inserting a host wait for the
                 * previous job to finish before this one can commence.
                 */
                host1x_cdma_push(&ch->cdma,
                                 host1x_opcode_setclass(HOST1X_CLASS_HOST1X,
                                        host1x_uclass_wait_syncpt_r(), 1),
                                 host1x_class_host_wait_syncpt(job->syncpt_id,
                                        host1x_syncpt_read_max(sp)));
        }

        /* Synchronize base register to allow using it for relative waiting */
        if (sp->base)
                synchronize_syncpt_base(job);

        syncval = host1x_syncpt_incr_max(sp, user_syncpt_incrs);

        host1x_hw_syncpt_assign_to_channel(host, sp, ch);

        job->syncpt_end = syncval;

        /* add a setclass for modules that require it */
        if (job->class)
                host1x_cdma_push(&ch->cdma,
                                 host1x_opcode_setclass(job->class, 0, 0),
                                 HOST1X_OPCODE_NOP);

        submit_gathers(job);

        /* end CDMA submit & stash pinned hMems into sync queue */
        host1x_cdma_end(&ch->cdma, job);

        trace_host1x_channel_submitted(dev_name(ch->dev), prev_max, syncval);

        /* schedule a submit complete interrupt */
        err = host1x_intr_add_action(host, sp, syncval,
                                     HOST1X_INTR_ACTION_SUBMIT_COMPLETE, ch,
                                     completed_waiter, NULL);
        completed_waiter = NULL;
        WARN(err, "Failed to set submit complete interrupt");

        mutex_unlock(&ch->submitlock);

        return 0;

error:
        kfree(completed_waiter);
        return err;
}

static void enable_gather_filter(struct host1x *host,
                                 struct host1x_channel *ch)
{
#if HOST1X_HW >= 6
        u32 val;

        if (!host->hv_regs)
                return;

        val = host1x_hypervisor_readl(
                host, HOST1X_HV_CH_KERNEL_FILTER_GBUFFER(ch->id / 32));
        val |= BIT(ch->id % 32);
        host1x_hypervisor_writel(
                host, val, HOST1X_HV_CH_KERNEL_FILTER_GBUFFER(ch->id / 32));
#elif HOST1X_HW >= 4
        host1x_ch_writel(ch,
                         HOST1X_CHANNEL_CHANNELCTRL_KERNEL_FILTER_GBUFFER(1),
                         HOST1X_CHANNEL_CHANNELCTRL);
#endif
}

static int host1x_channel_init(struct host1x_channel *ch, struct host1x *dev,
                               unsigned int index)
{
        ch->regs = dev->regs + index * HOST1X_CHANNEL_SIZE;
        enable_gather_filter(dev, ch);
        return 0;
}

static const struct host1x_channel_ops host1x_channel_ops = {
        .init = host1x_channel_init,
        .submit = channel_submit,
};