// SPDX-License-Identifier: GPL-2.0-only
//
// Copyright(c) 2020 Intel Corporation
//
// Author: Cezary Rojewski <cezary.rojewski@intel.com>
//

#include <linux/irqreturn.h>
#include "core.h"
#include "messages.h"
#include "registers.h"
#include "trace.h"

#define CATPT_IPC_TIMEOUT_MS    300

void catpt_ipc_init(struct catpt_ipc *ipc, struct device *dev)
{
        ipc->dev = dev;
        ipc->ready = false;
        ipc->default_timeout = CATPT_IPC_TIMEOUT_MS;
        init_completion(&ipc->done_completion);
        init_completion(&ipc->busy_completion);
        spin_lock_init(&ipc->lock);
        mutex_init(&ipc->mutex);
}

static int catpt_ipc_arm(struct catpt_ipc *ipc, struct catpt_fw_ready *config)
{
        /*
         * Both tx and rx are put into and received from outbox. Inbox is
         * only used for notifications where payload size is known upfront,
         * thus no separate buffer is allocated for it.
         */
        ipc->rx.data = devm_kzalloc(ipc->dev, config->outbox_size, GFP_KERNEL);
        if (!ipc->rx.data)
                return -ENOMEM;

        memcpy(&ipc->config, config, sizeof(*config));
        ipc->ready = true;

        return 0;
}

static void catpt_ipc_msg_init(struct catpt_ipc *ipc,
                               struct catpt_ipc_msg *reply)
{
        lockdep_assert_held(&ipc->lock);

        ipc->rx.header = 0;
        ipc->rx.size = reply ? reply->size : 0;
        reinit_completion(&ipc->done_completion);
        reinit_completion(&ipc->busy_completion);
}

static void catpt_dsp_send_tx(struct catpt_dev *cdev,
                              const struct catpt_ipc_msg *tx)
{
        u32 header = tx->header | CATPT_IPCC_BUSY;

        trace_catpt_ipc_request(header);
        trace_catpt_ipc_payload(tx->data, tx->size);

        memcpy_toio(catpt_outbox_addr(cdev), tx->data, tx->size);
        catpt_writel_shim(cdev, IPCC, header);
}

static int catpt_wait_msg_completion(struct catpt_dev *cdev, int timeout)
{
        struct catpt_ipc *ipc = &cdev->ipc;
        int ret;

        ret = wait_for_completion_timeout(&ipc->done_completion,
                                          msecs_to_jiffies(timeout));
        if (!ret)
                return -ETIMEDOUT;
        if (ipc->rx.rsp.status != CATPT_REPLY_PENDING)
                return 0;

        /* wait for delayed reply */
        ret = wait_for_completion_timeout(&ipc->busy_completion,
                                          msecs_to_jiffies(timeout));
        return ret ? 0 : -ETIMEDOUT;
}

static int catpt_dsp_do_send_msg(struct catpt_dev *cdev,
                                 struct catpt_ipc_msg request,
                                 struct catpt_ipc_msg *reply, int timeout, const char *name)
{
        struct catpt_ipc *ipc = &cdev->ipc;
        unsigned long flags;
        int ret;

        if (!ipc->ready)
                return -EPERM;
        if (request.size > ipc->config.outbox_size ||
            (reply && reply->size > ipc->config.outbox_size))
                return -EINVAL;

        spin_lock_irqsave(&ipc->lock, flags);
        catpt_ipc_msg_init(ipc, reply);
        catpt_dsp_send_tx(cdev, &request);
        spin_unlock_irqrestore(&ipc->lock, flags);

        ret = catpt_wait_msg_completion(cdev, timeout);
        if (ret) {
                dev_crit(cdev->dev, "communication severed: %d, rebooting dsp..\n",
                         ret);
                ipc->ready = false;
                /* TODO: attempt recovery */
                return ret;
        }

        ret = ipc->rx.rsp.status;
        if (ret)
                dev_err(cdev->dev, "%s (0x%08x) failed: %d\n", name, request.header, ret);
        if (reply) {
                reply->header = ipc->rx.header;

                if (!ret && reply->data)
                        memcpy(reply->data, ipc->rx.data, reply->size);
        }

        return ret;
}

int catpt_dsp_send_msg_timeout(struct catpt_dev *cdev,
                               struct catpt_ipc_msg request,
                               struct catpt_ipc_msg *reply, int timeout, const char *name)
{
        struct catpt_ipc *ipc = &cdev->ipc;
        int ret;

        mutex_lock(&ipc->mutex);
        ret = catpt_dsp_do_send_msg(cdev, request, reply, timeout, name);
        mutex_unlock(&ipc->mutex);

        return ret;
}

int catpt_dsp_send_msg(struct catpt_dev *cdev, struct catpt_ipc_msg request,
                       struct catpt_ipc_msg *reply, const char *name)
{
        return catpt_dsp_send_msg_timeout(cdev, request, reply,
                                          cdev->ipc.default_timeout, name);
}

static void
catpt_dsp_notify_stream(struct catpt_dev *cdev, union catpt_notify_msg msg)
{
        struct catpt_stream_runtime *stream;
        struct catpt_notify_position pos;
        struct catpt_notify_glitch glitch;

        stream = catpt_stream_find(cdev, msg.stream_hw_id);
        if (!stream) {
                dev_warn(cdev->dev, "notify %d for non-existent stream %d\n",
                         msg.notify_reason, msg.stream_hw_id);
                return;
        }

        switch (msg.notify_reason) {
        case CATPT_NOTIFY_POSITION_CHANGED:
                memcpy_fromio(&pos, catpt_inbox_addr(cdev), sizeof(pos));
                trace_catpt_ipc_payload((u8 *)&pos, sizeof(pos));

                catpt_stream_update_position(cdev, stream, &pos);
                break;

        case CATPT_NOTIFY_GLITCH_OCCURRED:
                memcpy_fromio(&glitch, catpt_inbox_addr(cdev), sizeof(glitch));
                trace_catpt_ipc_payload((u8 *)&glitch, sizeof(glitch));

                dev_warn(cdev->dev, "glitch %d at pos: 0x%08llx, wp: 0x%08x\n",
                         glitch.type, glitch.presentation_pos,
                         glitch.write_pos);
                break;

        default:
                dev_warn(cdev->dev, "unknown notification: %d received\n",
                         msg.notify_reason);
                break;
        }
}

static void catpt_dsp_copy_rx(struct catpt_dev *cdev, u32 header)
{
        struct catpt_ipc *ipc = &cdev->ipc;

        ipc->rx.header = header;
        if (ipc->rx.rsp.status != CATPT_REPLY_SUCCESS)
                return;

        memcpy_fromio(ipc->rx.data, catpt_outbox_addr(cdev), ipc->rx.size);
        trace_catpt_ipc_payload(ipc->rx.data, ipc->rx.size);
}

static void catpt_dsp_process_response(struct catpt_dev *cdev, u32 header)
{
        union catpt_notify_msg msg = CATPT_MSG(header);
        struct catpt_ipc *ipc = &cdev->ipc;

        if (msg.fw_ready) {
                struct catpt_fw_ready config;
                /* to fit 32b header original address is shifted right by 3 */
                u32 off = msg.mailbox_address << 3;

                memcpy_fromio(&config, cdev->lpe_ba + off, sizeof(config));
                trace_catpt_ipc_payload((u8 *)&config, sizeof(config));

                catpt_ipc_arm(ipc, &config);
                complete(&cdev->fw_ready);
                return;
        }

        switch (msg.global_msg_type) {
        case CATPT_GLB_REQUEST_CORE_DUMP:
                dev_err(cdev->dev, "ADSP device coredump received\n");
                ipc->ready = false;
                catpt_coredump(cdev);
                /* TODO: attempt recovery */
                break;

        case CATPT_GLB_STREAM_MESSAGE:
                switch (msg.stream_msg_type) {
                case CATPT_STRM_NOTIFICATION:
                        catpt_dsp_notify_stream(cdev, msg);
                        break;
                default:
                        catpt_dsp_copy_rx(cdev, header);
                        /* signal completion of delayed reply */
                        complete(&ipc->busy_completion);
                        break;
                }
                break;

        default:
                dev_warn(cdev->dev, "unknown response: %d received\n",
                         msg.global_msg_type);
                break;
        }
}

irqreturn_t catpt_dsp_irq_thread(int irq, void *dev_id)
{
        struct catpt_dev *cdev = dev_id;
        u32 ipcd;

        ipcd = catpt_readl_shim(cdev, IPCD);
        trace_catpt_ipc_notify(ipcd);

        /* ensure there is delayed reply or notification to process */
        if (!(ipcd & CATPT_IPCD_BUSY))
                return IRQ_NONE;

        catpt_dsp_process_response(cdev, ipcd);

        /* tell DSP processing is completed */
        catpt_updatel_shim(cdev, IPCD, CATPT_IPCD_BUSY | CATPT_IPCD_DONE,
                           CATPT_IPCD_DONE);
        /* unmask dsp BUSY interrupt */
        catpt_updatel_shim(cdev, IMC, CATPT_IMC_IPCDB, 0);

        return IRQ_HANDLED;
}

irqreturn_t catpt_dsp_irq_handler(int irq, void *dev_id)
{
        struct catpt_dev *cdev = dev_id;
        irqreturn_t ret = IRQ_NONE;
        u32 isc, ipcc;

        isc = catpt_readl_shim(cdev, ISC);
        trace_catpt_irq(isc);

        /* immediate reply */
        if (isc & CATPT_ISC_IPCCD) {
                /* mask host DONE interrupt */
                catpt_updatel_shim(cdev, IMC, CATPT_IMC_IPCCD, CATPT_IMC_IPCCD);

                ipcc = catpt_readl_shim(cdev, IPCC);
                trace_catpt_ipc_reply(ipcc);
                catpt_dsp_copy_rx(cdev, ipcc);
                complete(&cdev->ipc.done_completion);

                /* tell DSP processing is completed */
                catpt_updatel_shim(cdev, IPCC, CATPT_IPCC_DONE, 0);
                /* unmask host DONE interrupt */
                catpt_updatel_shim(cdev, IMC, CATPT_IMC_IPCCD, 0);
                ret = IRQ_HANDLED;
        }

        /* delayed reply or notification */
        if (isc & CATPT_ISC_IPCDB) {
                /* mask dsp BUSY interrupt */
                catpt_updatel_shim(cdev, IMC, CATPT_IMC_IPCDB, CATPT_IMC_IPCDB);
                ret = IRQ_WAKE_THREAD;
        }

        return ret;
}