root/drivers/net/wwan/iosm/iosm_ipc_imem.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2020-21 Intel Corporation.
 */

#include <linux/delay.h>

#include "iosm_ipc_chnl_cfg.h"
#include "iosm_ipc_devlink.h"
#include "iosm_ipc_flash.h"
#include "iosm_ipc_imem.h"
#include "iosm_ipc_port.h"
#include "iosm_ipc_trace.h"
#include "iosm_ipc_debugfs.h"

/* Check the wwan ips if it is valid with Channel as input. */
static int ipc_imem_check_wwan_ips(struct ipc_mem_channel *chnl)
{
        if (chnl)
                return chnl->ctype == IPC_CTYPE_WWAN &&
                       chnl->if_id == IPC_MEM_MUX_IP_CH_IF_ID;
        return false;
}

static int ipc_imem_msg_send_device_sleep(struct iosm_imem *ipc_imem, u32 state)
{
        union ipc_msg_prep_args prep_args = {
                .sleep.target = 1,
                .sleep.state = state,
        };

        ipc_imem->device_sleep = state;

        return ipc_protocol_tq_msg_send(ipc_imem->ipc_protocol,
                                        IPC_MSG_PREP_SLEEP, &prep_args, NULL);
}

static bool ipc_imem_dl_skb_alloc(struct iosm_imem *ipc_imem,
                                  struct ipc_pipe *pipe)
{
        /* limit max. nr of entries */
        if (pipe->nr_of_queued_entries >= pipe->max_nr_of_queued_entries)
                return false;

        return ipc_protocol_dl_td_prepare(ipc_imem->ipc_protocol, pipe);
}

/* This timer handler will retry DL buff allocation if a pipe has no free buf
 * and gives doorbell if TD is available
 */
static int ipc_imem_tq_td_alloc_timer(struct iosm_imem *ipc_imem, int arg,
                                      void *msg, size_t size)
{
        bool new_buffers_available = false;
        bool retry_allocation = false;
        int i;

        for (i = 0; i < IPC_MEM_MAX_CHANNELS; i++) {
                struct ipc_pipe *pipe = &ipc_imem->channels[i].dl_pipe;

                if (!pipe->is_open || pipe->nr_of_queued_entries > 0)
                        continue;

                while (ipc_imem_dl_skb_alloc(ipc_imem, pipe))
                        new_buffers_available = true;

                if (pipe->nr_of_queued_entries == 0)
                        retry_allocation = true;
        }

        if (new_buffers_available)
                ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                              IPC_HP_DL_PROCESS);

        if (retry_allocation) {
                ipc_imem->hrtimer_period =
                ktime_set(0, IPC_TD_ALLOC_TIMER_PERIOD_MS * 1000 * 1000ULL);
                if (!hrtimer_active(&ipc_imem->td_alloc_timer))
                        hrtimer_start(&ipc_imem->td_alloc_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
        }
        return 0;
}

static enum hrtimer_restart ipc_imem_td_alloc_timer_cb(struct hrtimer *hr_timer)
{
        struct iosm_imem *ipc_imem =
                container_of(hr_timer, struct iosm_imem, td_alloc_timer);
        /* Post an async tasklet event to trigger HP update Doorbell */
        ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_td_alloc_timer, 0, NULL,
                                 0, false);
        return HRTIMER_NORESTART;
}

/* Fast update timer tasklet handler to trigger HP update */
static int ipc_imem_tq_fast_update_timer_cb(struct iosm_imem *ipc_imem, int arg,
                                            void *msg, size_t size)
{
        ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                      IPC_HP_FAST_TD_UPD_TMR);

        return 0;
}

static enum hrtimer_restart
ipc_imem_fast_update_timer_cb(struct hrtimer *hr_timer)
{
        struct iosm_imem *ipc_imem =
                container_of(hr_timer, struct iosm_imem, fast_update_timer);
        /* Post an async tasklet event to trigger HP update Doorbell */
        ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_fast_update_timer_cb, 0,
                                 NULL, 0, false);
        return HRTIMER_NORESTART;
}

static int ipc_imem_tq_adb_timer_cb(struct iosm_imem *ipc_imem, int arg,
                                    void *msg, size_t size)
{
        ipc_mux_ul_adb_finish(ipc_imem->mux);
        return 0;
}

static enum hrtimer_restart
ipc_imem_adb_timer_cb(struct hrtimer *hr_timer)
{
        struct iosm_imem *ipc_imem =
                container_of(hr_timer, struct iosm_imem, adb_timer);

        ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_adb_timer_cb, 0,
                                 NULL, 0, false);
        return HRTIMER_NORESTART;
}

static int ipc_imem_setup_cp_mux_cap_init(struct iosm_imem *ipc_imem,
                                          struct ipc_mux_config *cfg)
{
        ipc_mmio_update_cp_capability(ipc_imem->mmio);

        if (ipc_imem->mmio->mux_protocol == MUX_UNKNOWN) {
                dev_err(ipc_imem->dev, "Failed to get Mux capability.");
                return -EINVAL;
        }

        cfg->protocol = ipc_imem->mmio->mux_protocol;

        cfg->ul_flow = (ipc_imem->mmio->has_ul_flow_credit == 1) ?
                               MUX_UL_ON_CREDITS :
                               MUX_UL;

        /* The instance ID is same as channel ID because this is been reused
         * for channel alloc function.
         */
        cfg->instance_id = IPC_MEM_MUX_IP_CH_IF_ID;

        return 0;
}

void ipc_imem_msg_send_feature_set(struct iosm_imem *ipc_imem,
                                   unsigned int reset_enable, bool atomic_ctx)
{
        union ipc_msg_prep_args prep_args = { .feature_set.reset_enable =
                                                      reset_enable };

        if (atomic_ctx)
                ipc_protocol_tq_msg_send(ipc_imem->ipc_protocol,
                                         IPC_MSG_PREP_FEATURE_SET, &prep_args,
                                         NULL);
        else
                ipc_protocol_msg_send(ipc_imem->ipc_protocol,
                                      IPC_MSG_PREP_FEATURE_SET, &prep_args);
}

/**
 * ipc_imem_td_update_timer_start - Starts the TD Update Timer if not started.
 * @ipc_imem:                       Pointer to imem data-struct
 */
void ipc_imem_td_update_timer_start(struct iosm_imem *ipc_imem)
{
        /* Use the TD update timer only in the runtime phase */
        if (!ipc_imem->enter_runtime || ipc_imem->td_update_timer_suspended) {
                /* trigger the doorbell irq on CP directly. */
                ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                              IPC_HP_TD_UPD_TMR_START);
                return;
        }

        if (!hrtimer_active(&ipc_imem->tdupdate_timer)) {
                ipc_imem->hrtimer_period =
                ktime_set(0, TD_UPDATE_DEFAULT_TIMEOUT_USEC * 1000ULL);
                if (!hrtimer_active(&ipc_imem->tdupdate_timer))
                        hrtimer_start(&ipc_imem->tdupdate_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
        }
}

void ipc_imem_hrtimer_stop(struct hrtimer *hr_timer)
{
        if (hrtimer_active(hr_timer))
                hrtimer_cancel(hr_timer);
}

/**
 * ipc_imem_adb_timer_start -   Starts the adb Timer if not starting.
 * @ipc_imem:                   Pointer to imem data-struct
 */
void ipc_imem_adb_timer_start(struct iosm_imem *ipc_imem)
{
        if (!hrtimer_active(&ipc_imem->adb_timer)) {
                ipc_imem->hrtimer_period =
                        ktime_set(0, IOSM_AGGR_MUX_ADB_FINISH_TIMEOUT_NSEC);
                hrtimer_start(&ipc_imem->adb_timer,
                              ipc_imem->hrtimer_period,
                              HRTIMER_MODE_REL);
        }
}

bool ipc_imem_ul_write_td(struct iosm_imem *ipc_imem)
{
        struct ipc_mem_channel *channel;
        bool hpda_ctrl_pending = false;
        struct sk_buff_head *ul_list;
        bool hpda_pending = false;
        struct ipc_pipe *pipe;
        int i;

        /* Analyze the uplink pipe of all active channels. */
        for (i = 0; i < ipc_imem->nr_of_channels; i++) {
                channel = &ipc_imem->channels[i];

                if (channel->state != IMEM_CHANNEL_ACTIVE)
                        continue;

                pipe = &channel->ul_pipe;

                /* Get the reference to the skbuf accumulator list. */
                ul_list = &channel->ul_list;

                /* Fill the transfer descriptor with the uplink buffer info. */
                if (!ipc_imem_check_wwan_ips(channel)) {
                        hpda_ctrl_pending |=
                                ipc_protocol_ul_td_send(ipc_imem->ipc_protocol,
                                                        pipe, ul_list);
                } else {
                        hpda_pending |=
                                ipc_protocol_ul_td_send(ipc_imem->ipc_protocol,
                                                        pipe, ul_list);
                }
        }

        /* forced HP update needed for non data channels */
        if (hpda_ctrl_pending) {
                hpda_pending = false;
                ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                              IPC_HP_UL_WRITE_TD);
        }

        return hpda_pending;
}

void ipc_imem_ipc_init_check(struct iosm_imem *ipc_imem)
{
        int timeout = IPC_MODEM_BOOT_TIMEOUT;

        ipc_imem->ipc_requested_state = IPC_MEM_DEVICE_IPC_INIT;

        /* Trigger the CP interrupt to enter the init state. */
        ipc_doorbell_fire(ipc_imem->pcie, IPC_DOORBELL_IRQ_IPC,
                          IPC_MEM_DEVICE_IPC_INIT);
        /* Wait for the CP update. */
        do {
                if (ipc_mmio_get_ipc_state(ipc_imem->mmio) ==
                    ipc_imem->ipc_requested_state) {
                        /* Prepare the MMIO space */
                        ipc_mmio_config(ipc_imem->mmio);

                        /* Trigger the CP irq to enter the running state. */
                        ipc_imem->ipc_requested_state =
                                IPC_MEM_DEVICE_IPC_RUNNING;
                        ipc_doorbell_fire(ipc_imem->pcie, IPC_DOORBELL_IRQ_IPC,
                                          IPC_MEM_DEVICE_IPC_RUNNING);

                        return;
                }
                msleep(20);
        } while (--timeout);

        /* timeout */
        dev_err(ipc_imem->dev, "%s: ipc_status(%d) ne. IPC_MEM_DEVICE_IPC_INIT",
                ipc_imem_phase_get_string(ipc_imem->phase),
                ipc_mmio_get_ipc_state(ipc_imem->mmio));

        ipc_uevent_send(ipc_imem->dev, UEVENT_MDM_TIMEOUT);
}

/* Analyze the packet type and distribute it. */
static void ipc_imem_dl_skb_process(struct iosm_imem *ipc_imem,
                                    struct ipc_pipe *pipe, struct sk_buff *skb)
{
        u16 port_id;

        if (!skb)
                return;

        /* An AT/control or IP packet is expected. */
        switch (pipe->channel->ctype) {
        case IPC_CTYPE_CTRL:
                port_id = pipe->channel->channel_id;
                ipc_pcie_addr_unmap(ipc_imem->pcie, IPC_CB(skb)->len,
                                    IPC_CB(skb)->mapping,
                                    IPC_CB(skb)->direction);
                if (port_id == IPC_MEM_CTRL_CHL_ID_7)
                        ipc_imem_sys_devlink_notify_rx(ipc_imem->ipc_devlink,
                                                       skb);
                else if (ipc_is_trace_channel(ipc_imem, port_id))
                        ipc_trace_port_rx(ipc_imem, skb);
                else
                        wwan_port_rx(ipc_imem->ipc_port[port_id]->iosm_port,
                                     skb);
                break;

        case IPC_CTYPE_WWAN:
                if (pipe->channel->if_id == IPC_MEM_MUX_IP_CH_IF_ID)
                        ipc_mux_dl_decode(ipc_imem->mux, skb);
                break;
        default:
                dev_err(ipc_imem->dev, "Invalid channel type");
                break;
        }
}

/* Process the downlink data and pass them to the char or net layer. */
static void ipc_imem_dl_pipe_process(struct iosm_imem *ipc_imem,
                                     struct ipc_pipe *pipe)
{
        s32 cnt = 0, processed_td_cnt = 0;
        struct ipc_mem_channel *channel;
        u32 head = 0, tail = 0;
        bool processed = false;
        struct sk_buff *skb;

        channel = pipe->channel;

        ipc_protocol_get_head_tail_index(ipc_imem->ipc_protocol, pipe, &head,
                                         &tail);
        if (pipe->old_tail != tail) {
                if (pipe->old_tail < tail)
                        cnt = tail - pipe->old_tail;
                else
                        cnt = pipe->nr_of_entries - pipe->old_tail + tail;
        }

        processed_td_cnt = cnt;

        /* Seek for pipes with pending DL data. */
        while (cnt--) {
                skb = ipc_protocol_dl_td_process(ipc_imem->ipc_protocol, pipe);

                /* Analyze the packet type and distribute it. */
                ipc_imem_dl_skb_process(ipc_imem, pipe, skb);
        }

        /* try to allocate new empty DL SKbs from head..tail - 1*/
        while (ipc_imem_dl_skb_alloc(ipc_imem, pipe))
                processed = true;

        if (processed && !ipc_imem_check_wwan_ips(channel)) {
                /* Force HP update for non IP channels */
                ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                              IPC_HP_DL_PROCESS);
                processed = false;

                /* If Fast Update timer is already running then stop */
                ipc_imem_hrtimer_stop(&ipc_imem->fast_update_timer);
        }

        /* Any control channel process will get immediate HP update.
         * Start Fast update timer only for IP channel if all the TDs were
         * used in last process.
         */
        if (processed && (processed_td_cnt == pipe->nr_of_entries - 1)) {
                ipc_imem->hrtimer_period =
                ktime_set(0, FORCE_UPDATE_DEFAULT_TIMEOUT_USEC * 1000ULL);
                hrtimer_start(&ipc_imem->fast_update_timer,
                              ipc_imem->hrtimer_period, HRTIMER_MODE_REL);
        }

        if (ipc_imem->app_notify_dl_pend)
                complete(&ipc_imem->dl_pend_sem);
}

/* process open uplink pipe */
static void ipc_imem_ul_pipe_process(struct iosm_imem *ipc_imem,
                                     struct ipc_pipe *pipe)
{
        struct ipc_mem_channel *channel;
        u32 tail = 0, head = 0;
        struct sk_buff *skb;
        s32 cnt = 0;

        channel = pipe->channel;

        /* Get the internal phase. */
        ipc_protocol_get_head_tail_index(ipc_imem->ipc_protocol, pipe, &head,
                                         &tail);

        if (pipe->old_tail != tail) {
                if (pipe->old_tail < tail)
                        cnt = tail - pipe->old_tail;
                else
                        cnt = pipe->nr_of_entries - pipe->old_tail + tail;
        }

        /* Free UL buffers. */
        while (cnt--) {
                skb = ipc_protocol_ul_td_process(ipc_imem->ipc_protocol, pipe);

                if (!skb)
                        continue;

                /* If the user app was suspended in uplink direction - blocking
                 * write, resume it.
                 */
                if (IPC_CB(skb)->op_type == UL_USR_OP_BLOCKED)
                        complete(&channel->ul_sem);

                /* Free the skbuf element. */
                if (IPC_CB(skb)->op_type == UL_MUX_OP_ADB) {
                        if (channel->if_id == IPC_MEM_MUX_IP_CH_IF_ID)
                                ipc_mux_ul_encoded_process(ipc_imem->mux, skb);
                        else
                                dev_err(ipc_imem->dev,
                                        "OP Type is UL_MUX, unknown if_id %d",
                                        channel->if_id);
                } else {
                        ipc_pcie_kfree_skb(ipc_imem->pcie, skb);
                }
        }

        /* Trace channel stats for IP UL pipe. */
        if (ipc_imem_check_wwan_ips(pipe->channel))
                ipc_mux_check_n_restart_tx(ipc_imem->mux);

        if (ipc_imem->app_notify_ul_pend)
                complete(&ipc_imem->ul_pend_sem);
}

/* Executes the irq. */
static void ipc_imem_rom_irq_exec(struct iosm_imem *ipc_imem)
{
        struct ipc_mem_channel *channel;

        channel = ipc_imem->ipc_devlink->devlink_sio.channel;
        ipc_imem->rom_exit_code = ipc_mmio_get_rom_exit_code(ipc_imem->mmio);
        complete(&channel->ul_sem);
}

/* Execute the UL bundle timer actions, generating the doorbell irq. */
static int ipc_imem_tq_td_update_timer_cb(struct iosm_imem *ipc_imem, int arg,
                                          void *msg, size_t size)
{
        ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol,
                                      IPC_HP_TD_UPD_TMR);
        return 0;
}

/* Consider link power management in the runtime phase. */
static void ipc_imem_slp_control_exec(struct iosm_imem *ipc_imem)
{
            /* link will go down, Test pending UL packets.*/
        if (ipc_protocol_pm_dev_sleep_handle(ipc_imem->ipc_protocol) &&
            hrtimer_active(&ipc_imem->tdupdate_timer)) {
                /* Generate the doorbell irq. */
                ipc_imem_tq_td_update_timer_cb(ipc_imem, 0, NULL, 0);
                /* Stop the TD update timer. */
                ipc_imem_hrtimer_stop(&ipc_imem->tdupdate_timer);
                /* Stop the fast update timer. */
                ipc_imem_hrtimer_stop(&ipc_imem->fast_update_timer);
        }
}

/* Execute startup timer and wait for delayed start (e.g. NAND) */
static int ipc_imem_tq_startup_timer_cb(struct iosm_imem *ipc_imem, int arg,
                                        void *msg, size_t size)
{
        /* Update & check the current operation phase. */
        if (ipc_imem_phase_update(ipc_imem) != IPC_P_RUN)
                return -EIO;

        if (ipc_mmio_get_ipc_state(ipc_imem->mmio) ==
            IPC_MEM_DEVICE_IPC_UNINIT) {
                ipc_imem->ipc_requested_state = IPC_MEM_DEVICE_IPC_INIT;

                ipc_doorbell_fire(ipc_imem->pcie, IPC_DOORBELL_IRQ_IPC,
                                  IPC_MEM_DEVICE_IPC_INIT);

                ipc_imem->hrtimer_period = ktime_set(0, 100 * 1000UL * 1000ULL);
                /* reduce period to 100 ms to check for mmio init state */
                if (!hrtimer_active(&ipc_imem->startup_timer))
                        hrtimer_start(&ipc_imem->startup_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
        } else if (ipc_mmio_get_ipc_state(ipc_imem->mmio) ==
                   IPC_MEM_DEVICE_IPC_INIT) {
                /* Startup complete  - disable timer */
                ipc_imem_hrtimer_stop(&ipc_imem->startup_timer);

                /* Prepare the MMIO space */
                ipc_mmio_config(ipc_imem->mmio);
                ipc_imem->ipc_requested_state = IPC_MEM_DEVICE_IPC_RUNNING;
                ipc_doorbell_fire(ipc_imem->pcie, IPC_DOORBELL_IRQ_IPC,
                                  IPC_MEM_DEVICE_IPC_RUNNING);
        }

        return 0;
}

static enum hrtimer_restart ipc_imem_startup_timer_cb(struct hrtimer *hr_timer)
{
        enum hrtimer_restart result = HRTIMER_NORESTART;
        struct iosm_imem *ipc_imem =
                container_of(hr_timer, struct iosm_imem, startup_timer);

        if (ktime_to_ns(ipc_imem->hrtimer_period)) {
                hrtimer_forward_now(&ipc_imem->startup_timer,
                                    ipc_imem->hrtimer_period);
                result = HRTIMER_RESTART;
        }

        ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_startup_timer_cb, 0,
                                 NULL, 0, false);
        return result;
}

/* Get the CP execution stage */
static enum ipc_mem_exec_stage
ipc_imem_get_exec_stage_buffered(struct iosm_imem *ipc_imem)
{
        return (ipc_imem->phase == IPC_P_RUN &&
                ipc_imem->ipc_status == IPC_MEM_DEVICE_IPC_RUNNING) ?
                       ipc_protocol_get_ap_exec_stage(ipc_imem->ipc_protocol) :
                       ipc_mmio_get_exec_stage(ipc_imem->mmio);
}

/* Callback to send the modem ready uevent */
static int ipc_imem_send_mdm_rdy_cb(struct iosm_imem *ipc_imem, int arg,
                                    void *msg, size_t size)
{
        enum ipc_mem_exec_stage exec_stage =
                ipc_imem_get_exec_stage_buffered(ipc_imem);

        if (exec_stage == IPC_MEM_EXEC_STAGE_RUN)
                ipc_uevent_send(ipc_imem->dev, UEVENT_MDM_READY);

        return 0;
}

/* This function is executed in a task context via an ipc_worker object,
 * as the creation or removal of device can't be done from tasklet.
 */
static void ipc_imem_run_state_worker(struct work_struct *instance)
{
        struct ipc_chnl_cfg chnl_cfg_port = { 0 };
        struct ipc_mux_config mux_cfg;
        struct iosm_imem *ipc_imem;
        u8 ctrl_chl_idx = 0;
        int ret;

        ipc_imem = container_of(instance, struct iosm_imem, run_state_worker);

        if (ipc_imem->phase != IPC_P_RUN) {
                dev_err(ipc_imem->dev,
                        "Modem link down. Exit run state worker.");
                goto err_out;
        }

        if (test_and_clear_bit(IOSM_DEVLINK_INIT, &ipc_imem->flag))
                ipc_devlink_deinit(ipc_imem->ipc_devlink);

        ret = ipc_imem_setup_cp_mux_cap_init(ipc_imem, &mux_cfg);
        if (ret < 0)
                goto err_out;

        ipc_imem->mux = ipc_mux_init(&mux_cfg, ipc_imem);
        if (!ipc_imem->mux)
                goto err_out;

        ret = ipc_imem_wwan_channel_init(ipc_imem, mux_cfg.protocol);
        if (ret < 0)
                goto err_ipc_mux_deinit;

        ipc_imem->mux->wwan = ipc_imem->wwan;

        while (ctrl_chl_idx < IPC_MEM_MAX_CHANNELS) {
                if (!ipc_chnl_cfg_get(&chnl_cfg_port, ctrl_chl_idx)) {
                        ipc_imem->ipc_port[ctrl_chl_idx] = NULL;

                        if (ipc_imem->pcie->pci->device == INTEL_CP_DEVICE_7560_ID &&
                            chnl_cfg_port.wwan_port_type == WWAN_PORT_XMMRPC) {
                                ctrl_chl_idx++;
                                continue;
                        }

                        if (ipc_imem->pcie->pci->device == INTEL_CP_DEVICE_7360_ID &&
                            chnl_cfg_port.wwan_port_type == WWAN_PORT_MBIM) {
                                ctrl_chl_idx++;
                                continue;
                        }
                        if (chnl_cfg_port.wwan_port_type != WWAN_PORT_UNKNOWN) {
                                ipc_imem_channel_init(ipc_imem, IPC_CTYPE_CTRL,
                                                      chnl_cfg_port,
                                                      IRQ_MOD_OFF);
                                ipc_imem->ipc_port[ctrl_chl_idx] =
                                        ipc_port_init(ipc_imem, chnl_cfg_port);
                        }
                }
                ctrl_chl_idx++;
        }

        ipc_debugfs_init(ipc_imem);

        ipc_task_queue_send_task(ipc_imem, ipc_imem_send_mdm_rdy_cb, 0, NULL, 0,
                                 false);

        /* Complete all memory stores before setting bit */
        smp_mb__before_atomic();

        set_bit(FULLY_FUNCTIONAL, &ipc_imem->flag);

        /* Complete all memory stores after setting bit */
        smp_mb__after_atomic();

        return;

err_ipc_mux_deinit:
        ipc_mux_deinit(ipc_imem->mux);
err_out:
        ipc_uevent_send(ipc_imem->dev, UEVENT_CD_READY_LINK_DOWN);
}

static void ipc_imem_handle_irq(struct iosm_imem *ipc_imem, int irq)
{
        enum ipc_mem_device_ipc_state curr_ipc_status;
        enum ipc_phase old_phase, phase;
        bool retry_allocation = false;
        bool ul_pending = false;
        int i;

        if (irq != IMEM_IRQ_DONT_CARE)
                ipc_imem->ev_irq_pending[irq] = false;

        /* Get the internal phase. */
        old_phase = ipc_imem->phase;

        if (old_phase == IPC_P_OFF_REQ) {
                dev_dbg(ipc_imem->dev,
                        "[%s]: Ignoring MSI. Deinit sequence in progress!",
                        ipc_imem_phase_get_string(old_phase));
                return;
        }

        /* Update the phase controlled by CP. */
        phase = ipc_imem_phase_update(ipc_imem);

        switch (phase) {
        case IPC_P_RUN:
                if (!ipc_imem->enter_runtime) {
                        /* Excute the transition from flash/boot to runtime. */
                        ipc_imem->enter_runtime = 1;

                        /* allow device to sleep, default value is
                         * IPC_HOST_SLEEP_ENTER_SLEEP
                         */
                        ipc_imem_msg_send_device_sleep(ipc_imem,
                                                       ipc_imem->device_sleep);

                        ipc_imem_msg_send_feature_set(ipc_imem,
                                                      IPC_MEM_INBAND_CRASH_SIG,
                                                  true);
                }

                curr_ipc_status =
                        ipc_protocol_get_ipc_status(ipc_imem->ipc_protocol);

                /* check ipc_status change */
                if (ipc_imem->ipc_status != curr_ipc_status) {
                        ipc_imem->ipc_status = curr_ipc_status;

                        if (ipc_imem->ipc_status ==
                            IPC_MEM_DEVICE_IPC_RUNNING) {
                                schedule_work(&ipc_imem->run_state_worker);
                        }
                }

                /* Consider power management in the runtime phase. */
                ipc_imem_slp_control_exec(ipc_imem);
                break; /* Continue with skbuf processing. */

                /* Unexpected phases. */
        case IPC_P_OFF:
        case IPC_P_OFF_REQ:
                dev_err(ipc_imem->dev, "confused phase %s",
                        ipc_imem_phase_get_string(phase));
                return;

        case IPC_P_PSI:
                if (old_phase != IPC_P_ROM)
                        break;

                fallthrough;
                /* On CP the PSI phase is already active. */

        case IPC_P_ROM:
                /* Before CP ROM driver starts the PSI image, it sets
                 * the exit_code field on the doorbell scratchpad and
                 * triggers the irq.
                 */
                ipc_imem_rom_irq_exec(ipc_imem);
                return;

        default:
                break;
        }

        /* process message ring */
        ipc_protocol_msg_process(ipc_imem, irq);

        /* process all open pipes */
        for (i = 0; i < IPC_MEM_MAX_CHANNELS; i++) {
                struct ipc_pipe *ul_pipe = &ipc_imem->channels[i].ul_pipe;
                struct ipc_pipe *dl_pipe = &ipc_imem->channels[i].dl_pipe;

                if (dl_pipe->is_open &&
                    (irq == IMEM_IRQ_DONT_CARE || irq == dl_pipe->irq)) {
                        ipc_imem_dl_pipe_process(ipc_imem, dl_pipe);

                        if (dl_pipe->nr_of_queued_entries == 0)
                                retry_allocation = true;
                }

                if (ul_pipe->is_open)
                        ipc_imem_ul_pipe_process(ipc_imem, ul_pipe);
        }

        /* Try to generate new ADB or ADGH. */
        if (ipc_mux_ul_data_encode(ipc_imem->mux)) {
                ipc_imem_td_update_timer_start(ipc_imem);
                if (ipc_imem->mux->protocol == MUX_AGGREGATION)
                        ipc_imem_adb_timer_start(ipc_imem);
        }

        /* Continue the send procedure with accumulated SIO or NETIF packets.
         * Reset the debounce flags.
         */
        ul_pending |= ipc_imem_ul_write_td(ipc_imem);

        /* if UL data is pending restart TD update timer */
        if (ul_pending) {
                ipc_imem->hrtimer_period =
                ktime_set(0, TD_UPDATE_DEFAULT_TIMEOUT_USEC * 1000ULL);
                if (!hrtimer_active(&ipc_imem->tdupdate_timer))
                        hrtimer_start(&ipc_imem->tdupdate_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
        }

        /* If CP has executed the transition
         * from IPC_INIT to IPC_RUNNING in the PSI
         * phase, wake up the flash app to open the pipes.
         */
        if ((phase == IPC_P_PSI || phase == IPC_P_EBL) &&
            ipc_imem->ipc_requested_state == IPC_MEM_DEVICE_IPC_RUNNING &&
            ipc_mmio_get_ipc_state(ipc_imem->mmio) ==
                                                IPC_MEM_DEVICE_IPC_RUNNING) {
                complete(&ipc_imem->ipc_devlink->devlink_sio.channel->ul_sem);
        }

        /* Reset the expected CP state. */
        ipc_imem->ipc_requested_state = IPC_MEM_DEVICE_IPC_DONT_CARE;

        if (retry_allocation) {
                ipc_imem->hrtimer_period =
                ktime_set(0, IPC_TD_ALLOC_TIMER_PERIOD_MS * 1000 * 1000ULL);
                if (!hrtimer_active(&ipc_imem->td_alloc_timer))
                        hrtimer_start(&ipc_imem->td_alloc_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
        }
}

/* Callback by tasklet for handling interrupt events. */
static int ipc_imem_tq_irq_cb(struct iosm_imem *ipc_imem, int arg, void *msg,
                              size_t size)
{
        ipc_imem_handle_irq(ipc_imem, arg);

        return 0;
}

void ipc_imem_ul_send(struct iosm_imem *ipc_imem)
{
        /* start doorbell irq delay timer if UL is pending */
        if (ipc_imem_ul_write_td(ipc_imem))
                ipc_imem_td_update_timer_start(ipc_imem);
}

/* Check the execution stage and update the AP phase */
static enum ipc_phase ipc_imem_phase_update_check(struct iosm_imem *ipc_imem,
                                                  enum ipc_mem_exec_stage stage)
{
        switch (stage) {
        case IPC_MEM_EXEC_STAGE_BOOT:
                if (ipc_imem->phase != IPC_P_ROM) {
                        /* Send this event only once */
                        ipc_uevent_send(ipc_imem->dev, UEVENT_ROM_READY);
                }

                ipc_imem->phase = IPC_P_ROM;
                break;

        case IPC_MEM_EXEC_STAGE_PSI:
                ipc_imem->phase = IPC_P_PSI;
                break;

        case IPC_MEM_EXEC_STAGE_EBL:
                ipc_imem->phase = IPC_P_EBL;
                break;

        case IPC_MEM_EXEC_STAGE_RUN:
                if (ipc_imem->phase != IPC_P_RUN &&
                    ipc_imem->ipc_status == IPC_MEM_DEVICE_IPC_RUNNING) {
                        ipc_uevent_send(ipc_imem->dev, UEVENT_MDM_READY);
                }
                ipc_imem->phase = IPC_P_RUN;
                break;

        case IPC_MEM_EXEC_STAGE_CRASH:
                if (ipc_imem->phase != IPC_P_CRASH)
                        ipc_uevent_send(ipc_imem->dev, UEVENT_CRASH);

                ipc_imem->phase = IPC_P_CRASH;
                break;

        case IPC_MEM_EXEC_STAGE_CD_READY:
                if (ipc_imem->phase != IPC_P_CD_READY)
                        ipc_uevent_send(ipc_imem->dev, UEVENT_CD_READY);
                ipc_imem->phase = IPC_P_CD_READY;
                break;

        default:
                /* unknown exec stage:
                 * assume that link is down and send info to listeners
                 */
                ipc_uevent_send(ipc_imem->dev, UEVENT_CD_READY_LINK_DOWN);
                break;
        }

        return ipc_imem->phase;
}

/* Send msg to device to open pipe */
static bool ipc_imem_pipe_open(struct iosm_imem *ipc_imem,
                               struct ipc_pipe *pipe)
{
        union ipc_msg_prep_args prep_args = {
                .pipe_open.pipe = pipe,
        };

        if (ipc_protocol_msg_send(ipc_imem->ipc_protocol,
                                  IPC_MSG_PREP_PIPE_OPEN, &prep_args) == 0)
                pipe->is_open = true;

        return pipe->is_open;
}

/* Allocates the TDs for the given pipe along with firing HP update DB. */
static int ipc_imem_tq_pipe_td_alloc(struct iosm_imem *ipc_imem, int arg,
                                     void *msg, size_t size)
{
        struct ipc_pipe *dl_pipe = msg;
        bool processed = false;
        int i;

        for (i = 0; i < dl_pipe->nr_of_entries - 1; i++)
                processed |= ipc_imem_dl_skb_alloc(ipc_imem, dl_pipe);

        /* Trigger the doorbell irq to inform CP that new downlink buffers are
         * available.
         */
        if (processed)
                ipc_protocol_doorbell_trigger(ipc_imem->ipc_protocol, arg);

        return 0;
}

static enum hrtimer_restart
ipc_imem_td_update_timer_cb(struct hrtimer *hr_timer)
{
        struct iosm_imem *ipc_imem =
                container_of(hr_timer, struct iosm_imem, tdupdate_timer);

        ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_td_update_timer_cb, 0,
                                 NULL, 0, false);
        return HRTIMER_NORESTART;
}

/* Get the CP execution state and map it to the AP phase. */
enum ipc_phase ipc_imem_phase_update(struct iosm_imem *ipc_imem)
{
        enum ipc_mem_exec_stage exec_stage =
                                ipc_imem_get_exec_stage_buffered(ipc_imem);
        /* If the CP stage is undef, return the internal precalculated phase. */
        return ipc_imem->phase == IPC_P_OFF_REQ ?
                       ipc_imem->phase :
                       ipc_imem_phase_update_check(ipc_imem, exec_stage);
}

const char *ipc_imem_phase_get_string(enum ipc_phase phase)
{
        switch (phase) {
        case IPC_P_RUN:
                return "A-RUN";

        case IPC_P_OFF:
                return "A-OFF";

        case IPC_P_ROM:
                return "A-ROM";

        case IPC_P_PSI:
                return "A-PSI";

        case IPC_P_EBL:
                return "A-EBL";

        case IPC_P_CRASH:
                return "A-CRASH";

        case IPC_P_CD_READY:
                return "A-CD_READY";

        case IPC_P_OFF_REQ:
                return "A-OFF_REQ";

        default:
                return "A-???";
        }
}

void ipc_imem_pipe_close(struct iosm_imem *ipc_imem, struct ipc_pipe *pipe)
{
        union ipc_msg_prep_args prep_args = { .pipe_close.pipe = pipe };

        pipe->is_open = false;
        ipc_protocol_msg_send(ipc_imem->ipc_protocol, IPC_MSG_PREP_PIPE_CLOSE,
                              &prep_args);

        ipc_imem_pipe_cleanup(ipc_imem, pipe);
}

void ipc_imem_channel_close(struct iosm_imem *ipc_imem, int channel_id)
{
        struct ipc_mem_channel *channel;

        if (channel_id < 0 || channel_id >= ipc_imem->nr_of_channels) {
                dev_err(ipc_imem->dev, "invalid channel id %d", channel_id);
                return;
        }

        channel = &ipc_imem->channels[channel_id];

        if (channel->state == IMEM_CHANNEL_FREE) {
                dev_err(ipc_imem->dev, "ch[%d]: invalid channel state %d",
                        channel_id, channel->state);
                return;
        }

        /* Free only the channel id in the CP power off mode. */
        if (channel->state == IMEM_CHANNEL_RESERVED)
                /* Release only the channel id. */
                goto channel_free;

        if (ipc_imem->phase == IPC_P_RUN) {
                ipc_imem_pipe_close(ipc_imem, &channel->ul_pipe);
                ipc_imem_pipe_close(ipc_imem, &channel->dl_pipe);
        }

        ipc_imem_pipe_cleanup(ipc_imem, &channel->ul_pipe);
        ipc_imem_pipe_cleanup(ipc_imem, &channel->dl_pipe);

channel_free:
        ipc_imem_channel_free(channel);
}

struct ipc_mem_channel *ipc_imem_channel_open(struct iosm_imem *ipc_imem,
                                              int channel_id, u32 db_id)
{
        struct ipc_mem_channel *channel;

        if (channel_id < 0 || channel_id >= IPC_MEM_MAX_CHANNELS) {
                dev_err(ipc_imem->dev, "invalid channel ID: %d", channel_id);
                return NULL;
        }

        channel = &ipc_imem->channels[channel_id];

        channel->state = IMEM_CHANNEL_ACTIVE;

        if (!ipc_imem_pipe_open(ipc_imem, &channel->ul_pipe))
                goto ul_pipe_err;

        if (!ipc_imem_pipe_open(ipc_imem, &channel->dl_pipe))
                goto dl_pipe_err;

        /* Allocate the downlink buffers in tasklet context. */
        if (ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_pipe_td_alloc, db_id,
                                     &channel->dl_pipe, 0, false)) {
                dev_err(ipc_imem->dev, "td allocation failed : %d", channel_id);
                goto task_failed;
        }

        /* Active channel. */
        return channel;
task_failed:
        ipc_imem_pipe_close(ipc_imem, &channel->dl_pipe);
dl_pipe_err:
        ipc_imem_pipe_close(ipc_imem, &channel->ul_pipe);
ul_pipe_err:
        ipc_imem_channel_free(channel);
        return NULL;
}

void ipc_imem_pm_suspend(struct iosm_imem *ipc_imem)
{
        ipc_protocol_suspend(ipc_imem->ipc_protocol);
}

void ipc_imem_pm_s2idle_sleep(struct iosm_imem *ipc_imem, bool sleep)
{
        ipc_protocol_s2idle_sleep(ipc_imem->ipc_protocol, sleep);
}

void ipc_imem_pm_resume(struct iosm_imem *ipc_imem)
{
        enum ipc_mem_exec_stage stage;

        if (ipc_protocol_resume(ipc_imem->ipc_protocol)) {
                stage = ipc_mmio_get_exec_stage(ipc_imem->mmio);
                ipc_imem_phase_update_check(ipc_imem, stage);
        }
}

void ipc_imem_channel_free(struct ipc_mem_channel *channel)
{
        /* Reset dynamic channel elements. */
        channel->state = IMEM_CHANNEL_FREE;
}

int ipc_imem_channel_alloc(struct iosm_imem *ipc_imem, int index,
                           enum ipc_ctype ctype)
{
        struct ipc_mem_channel *channel;
        int i;

        /* Find channel of given type/index */
        for (i = 0; i < ipc_imem->nr_of_channels; i++) {
                channel = &ipc_imem->channels[i];
                if (channel->ctype == ctype && channel->index == index)
                        break;
        }

        if (i >= ipc_imem->nr_of_channels) {
                dev_dbg(ipc_imem->dev,
                        "no channel definition for index=%d ctype=%d", index,
                        ctype);
                return -ECHRNG;
        }

        if (ipc_imem->channels[i].state != IMEM_CHANNEL_FREE) {
                dev_dbg(ipc_imem->dev, "channel is in use");
                return -EBUSY;
        }

        if (channel->ctype == IPC_CTYPE_WWAN &&
            index == IPC_MEM_MUX_IP_CH_IF_ID)
                channel->if_id = index;

        channel->channel_id = index;
        channel->state = IMEM_CHANNEL_RESERVED;

        return i;
}

void ipc_imem_channel_init(struct iosm_imem *ipc_imem, enum ipc_ctype ctype,
                           struct ipc_chnl_cfg chnl_cfg, u32 irq_moderation)
{
        struct ipc_mem_channel *channel;

        if (chnl_cfg.ul_pipe >= IPC_MEM_MAX_PIPES ||
            chnl_cfg.dl_pipe >= IPC_MEM_MAX_PIPES) {
                dev_err(ipc_imem->dev, "invalid pipe: ul_pipe=%d, dl_pipe=%d",
                        chnl_cfg.ul_pipe, chnl_cfg.dl_pipe);
                return;
        }

        if (ipc_imem->nr_of_channels >= IPC_MEM_MAX_CHANNELS) {
                dev_err(ipc_imem->dev, "too many channels");
                return;
        }

        channel = &ipc_imem->channels[ipc_imem->nr_of_channels];
        channel->channel_id = ipc_imem->nr_of_channels;
        channel->ctype = ctype;
        channel->index = chnl_cfg.id;
        channel->net_err_count = 0;
        channel->state = IMEM_CHANNEL_FREE;
        ipc_imem->nr_of_channels++;

        ipc_imem_channel_update(ipc_imem, channel->channel_id, chnl_cfg,
                                IRQ_MOD_OFF);

        skb_queue_head_init(&channel->ul_list);

        init_completion(&channel->ul_sem);
}

void ipc_imem_channel_update(struct iosm_imem *ipc_imem, int id,
                             struct ipc_chnl_cfg chnl_cfg, u32 irq_moderation)
{
        struct ipc_mem_channel *channel;

        if (id < 0 || id >= ipc_imem->nr_of_channels) {
                dev_err(ipc_imem->dev, "invalid channel id %d", id);
                return;
        }

        channel = &ipc_imem->channels[id];

        if (channel->state != IMEM_CHANNEL_FREE &&
            channel->state != IMEM_CHANNEL_RESERVED) {
                dev_err(ipc_imem->dev, "invalid channel state %d",
                        channel->state);
                return;
        }

        channel->ul_pipe.nr_of_entries = chnl_cfg.ul_nr_of_entries;
        channel->ul_pipe.pipe_nr = chnl_cfg.ul_pipe;
        channel->ul_pipe.is_open = false;
        channel->ul_pipe.irq = IPC_UL_PIPE_IRQ_VECTOR;
        channel->ul_pipe.channel = channel;
        channel->ul_pipe.dir = IPC_MEM_DIR_UL;
        channel->ul_pipe.accumulation_backoff = chnl_cfg.accumulation_backoff;
        channel->ul_pipe.irq_moderation = irq_moderation;
        channel->ul_pipe.buf_size = 0;

        channel->dl_pipe.nr_of_entries = chnl_cfg.dl_nr_of_entries;
        channel->dl_pipe.pipe_nr = chnl_cfg.dl_pipe;
        channel->dl_pipe.is_open = false;
        channel->dl_pipe.irq = IPC_DL_PIPE_IRQ_VECTOR;
        channel->dl_pipe.channel = channel;
        channel->dl_pipe.dir = IPC_MEM_DIR_DL;
        channel->dl_pipe.accumulation_backoff = chnl_cfg.accumulation_backoff;
        channel->dl_pipe.irq_moderation = irq_moderation;
        channel->dl_pipe.buf_size = chnl_cfg.dl_buf_size;
}

static void ipc_imem_channel_reset(struct iosm_imem *ipc_imem)
{
        int i;

        for (i = 0; i < ipc_imem->nr_of_channels; i++) {
                struct ipc_mem_channel *channel;

                channel = &ipc_imem->channels[i];

                ipc_imem_pipe_cleanup(ipc_imem, &channel->dl_pipe);
                ipc_imem_pipe_cleanup(ipc_imem, &channel->ul_pipe);

                ipc_imem_channel_free(channel);
        }
}

void ipc_imem_pipe_cleanup(struct iosm_imem *ipc_imem, struct ipc_pipe *pipe)
{
        struct sk_buff *skb;

        /* Force pipe to closed state also when not explicitly closed through
         * ipc_imem_pipe_close()
         */
        pipe->is_open = false;

        /* Empty the uplink skb accumulator. */
        while ((skb = skb_dequeue(&pipe->channel->ul_list)))
                ipc_pcie_kfree_skb(ipc_imem->pcie, skb);

        ipc_protocol_pipe_cleanup(ipc_imem->ipc_protocol, pipe);
}

/* Send IPC protocol uninit to the modem when Link is active. */
static void ipc_imem_device_ipc_uninit(struct iosm_imem *ipc_imem)
{
        int timeout = IPC_MODEM_UNINIT_TIMEOUT_MS;
        enum ipc_mem_device_ipc_state ipc_state;

        /* When PCIe link is up set IPC_UNINIT
         * of the modem otherwise ignore it when PCIe link down happens.
         */
        if (ipc_pcie_check_data_link_active(ipc_imem->pcie)) {
                /* set modem to UNINIT
                 * (in case we want to reload the AP driver without resetting
                 * the modem)
                 */
                ipc_doorbell_fire(ipc_imem->pcie, IPC_DOORBELL_IRQ_IPC,
                                  IPC_MEM_DEVICE_IPC_UNINIT);
                ipc_state = ipc_mmio_get_ipc_state(ipc_imem->mmio);

                /* Wait for maximum 30ms to allow the Modem to uninitialize the
                 * protocol.
                 */
                while ((ipc_state <= IPC_MEM_DEVICE_IPC_DONT_CARE) &&
                       (ipc_state != IPC_MEM_DEVICE_IPC_UNINIT) &&
                       (timeout > 0)) {
                        usleep_range(1000, 1250);
                        timeout--;
                        ipc_state = ipc_mmio_get_ipc_state(ipc_imem->mmio);
                }
        }
}

void ipc_imem_cleanup(struct iosm_imem *ipc_imem)
{
        ipc_imem->phase = IPC_P_OFF_REQ;

        /* forward MDM_NOT_READY to listeners */
        ipc_uevent_send(ipc_imem->dev, UEVENT_MDM_NOT_READY);

        hrtimer_cancel(&ipc_imem->td_alloc_timer);
        hrtimer_cancel(&ipc_imem->tdupdate_timer);
        hrtimer_cancel(&ipc_imem->fast_update_timer);
        hrtimer_cancel(&ipc_imem->startup_timer);

        /* cancel the workqueue */
        cancel_work_sync(&ipc_imem->run_state_worker);

        if (test_and_clear_bit(FULLY_FUNCTIONAL, &ipc_imem->flag)) {
                ipc_mux_deinit(ipc_imem->mux);
                ipc_debugfs_deinit(ipc_imem);
                ipc_wwan_deinit(ipc_imem->wwan);
                ipc_port_deinit(ipc_imem->ipc_port);
        }

        if (test_and_clear_bit(IOSM_DEVLINK_INIT, &ipc_imem->flag))
                ipc_devlink_deinit(ipc_imem->ipc_devlink);

        ipc_imem_device_ipc_uninit(ipc_imem);
        ipc_imem_channel_reset(ipc_imem);

        ipc_protocol_deinit(ipc_imem->ipc_protocol);
        ipc_task_deinit(ipc_imem->ipc_task);

        kfree(ipc_imem->ipc_task);
        kfree(ipc_imem->mmio);

        ipc_imem->phase = IPC_P_OFF;
}

/* After CP has unblocked the PCIe link, save the start address of the doorbell
 * scratchpad and prepare the shared memory region. If the flashing to RAM
 * procedure shall be executed, copy the chip information from the doorbell
 * scratchtpad to the application buffer and wake up the flash app.
 */
static int ipc_imem_config(struct iosm_imem *ipc_imem)
{
        enum ipc_phase phase;

        /* Initialize the semaphore for the blocking read UL/DL transfer. */
        init_completion(&ipc_imem->ul_pend_sem);

        init_completion(&ipc_imem->dl_pend_sem);

        /* clear internal flags */
        ipc_imem->ipc_status = IPC_MEM_DEVICE_IPC_UNINIT;
        ipc_imem->enter_runtime = 0;

        phase = ipc_imem_phase_update(ipc_imem);

        /* Either CP shall be in the power off or power on phase. */
        switch (phase) {
        case IPC_P_ROM:
                ipc_imem->hrtimer_period = ktime_set(0, 1000 * 1000 * 1000ULL);
                /* poll execution stage (for delayed start, e.g. NAND) */
                if (!hrtimer_active(&ipc_imem->startup_timer))
                        hrtimer_start(&ipc_imem->startup_timer,
                                      ipc_imem->hrtimer_period,
                                      HRTIMER_MODE_REL);
                return 0;

        case IPC_P_PSI:
        case IPC_P_EBL:
        case IPC_P_RUN:
                /* The initial IPC state is IPC_MEM_DEVICE_IPC_UNINIT. */
                ipc_imem->ipc_requested_state = IPC_MEM_DEVICE_IPC_UNINIT;

                /* Verify the exepected initial state. */
                if (ipc_imem->ipc_requested_state ==
                    ipc_mmio_get_ipc_state(ipc_imem->mmio)) {
                        ipc_imem_ipc_init_check(ipc_imem);

                        return 0;
                }
                dev_err(ipc_imem->dev,
                        "ipc_status(%d) != IPC_MEM_DEVICE_IPC_UNINIT",
                        ipc_mmio_get_ipc_state(ipc_imem->mmio));
                break;
        case IPC_P_CRASH:
        case IPC_P_CD_READY:
                dev_dbg(ipc_imem->dev,
                        "Modem is in phase %d, reset Modem to collect CD",
                        phase);
                return 0;
        default:
                dev_err(ipc_imem->dev, "unexpected operation phase %d", phase);
                break;
        }

        complete(&ipc_imem->dl_pend_sem);
        complete(&ipc_imem->ul_pend_sem);
        ipc_imem->phase = IPC_P_OFF;
        return -EIO;
}

/* Pass the dev ptr to the shared memory driver and request the entry points */
struct iosm_imem *ipc_imem_init(struct iosm_pcie *pcie, unsigned int device_id,
                                void __iomem *mmio, struct device *dev)
{
        struct iosm_imem *ipc_imem = kzalloc_obj(*pcie->imem);
        enum ipc_mem_exec_stage stage;

        if (!ipc_imem)
                return NULL;

        /* Save the device address. */
        ipc_imem->pcie = pcie;
        ipc_imem->dev = dev;

        ipc_imem->pci_device_id = device_id;

        ipc_imem->cp_version = 0;
        ipc_imem->device_sleep = IPC_HOST_SLEEP_ENTER_SLEEP;

        /* Reset the max number of configured channels */
        ipc_imem->nr_of_channels = 0;

        /* allocate IPC MMIO */
        ipc_imem->mmio = ipc_mmio_init(mmio, ipc_imem->dev);
        if (!ipc_imem->mmio) {
                dev_err(ipc_imem->dev, "failed to initialize mmio region");
                goto mmio_init_fail;
        }

        ipc_imem->ipc_task = kzalloc_obj(*ipc_imem->ipc_task);

        /* Create tasklet for event handling*/
        if (!ipc_imem->ipc_task)
                goto ipc_task_fail;

        if (ipc_task_init(ipc_imem->ipc_task))
                goto ipc_task_init_fail;

        ipc_imem->ipc_task->dev = ipc_imem->dev;

        INIT_WORK(&ipc_imem->run_state_worker, ipc_imem_run_state_worker);

        ipc_imem->ipc_protocol = ipc_protocol_init(ipc_imem);

        if (!ipc_imem->ipc_protocol)
                goto protocol_init_fail;

        /* The phase is set to power off. */
        ipc_imem->phase = IPC_P_OFF;

        hrtimer_setup(&ipc_imem->startup_timer, ipc_imem_startup_timer_cb, CLOCK_MONOTONIC,
                      HRTIMER_MODE_REL);

        hrtimer_setup(&ipc_imem->tdupdate_timer, ipc_imem_td_update_timer_cb, CLOCK_MONOTONIC,
                      HRTIMER_MODE_REL);

        hrtimer_setup(&ipc_imem->fast_update_timer, ipc_imem_fast_update_timer_cb, CLOCK_MONOTONIC,
                      HRTIMER_MODE_REL);

        hrtimer_setup(&ipc_imem->td_alloc_timer, ipc_imem_td_alloc_timer_cb, CLOCK_MONOTONIC,
                      HRTIMER_MODE_REL);

        hrtimer_setup(&ipc_imem->adb_timer, ipc_imem_adb_timer_cb, CLOCK_MONOTONIC,
                      HRTIMER_MODE_REL);

        if (ipc_imem_config(ipc_imem)) {
                dev_err(ipc_imem->dev, "failed to initialize the imem");
                goto imem_config_fail;
        }

        stage = ipc_mmio_get_exec_stage(ipc_imem->mmio);
        if (stage == IPC_MEM_EXEC_STAGE_BOOT) {
                /* Alloc and Register devlink */
                ipc_imem->ipc_devlink = ipc_devlink_init(ipc_imem);
                if (!ipc_imem->ipc_devlink) {
                        dev_err(ipc_imem->dev, "Devlink register failed");
                        goto imem_config_fail;
                }

                if (ipc_flash_link_establish(ipc_imem))
                        goto devlink_channel_fail;

                set_bit(IOSM_DEVLINK_INIT, &ipc_imem->flag);
        }
        return ipc_imem;
devlink_channel_fail:
        ipc_devlink_deinit(ipc_imem->ipc_devlink);
imem_config_fail:
        hrtimer_cancel(&ipc_imem->td_alloc_timer);
        hrtimer_cancel(&ipc_imem->fast_update_timer);
        hrtimer_cancel(&ipc_imem->tdupdate_timer);
        hrtimer_cancel(&ipc_imem->startup_timer);
protocol_init_fail:
        cancel_work_sync(&ipc_imem->run_state_worker);
        ipc_task_deinit(ipc_imem->ipc_task);
ipc_task_init_fail:
        kfree(ipc_imem->ipc_task);
ipc_task_fail:
        kfree(ipc_imem->mmio);
mmio_init_fail:
        kfree(ipc_imem);
        return NULL;
}

void ipc_imem_irq_process(struct iosm_imem *ipc_imem, int irq)
{
        /* Debounce IPC_EV_IRQ. */
        if (ipc_imem && !ipc_imem->ev_irq_pending[irq]) {
                ipc_imem->ev_irq_pending[irq] = true;
                ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_irq_cb, irq,
                                         NULL, 0, false);
        }
}

void ipc_imem_td_update_timer_suspend(struct iosm_imem *ipc_imem, bool suspend)
{
        ipc_imem->td_update_timer_suspended = suspend;
}

/* Verify the CP execution state, copy the chip info,
 * change the execution phase to ROM
 */
static int ipc_imem_devlink_trigger_chip_info_cb(struct iosm_imem *ipc_imem,
                                                 int arg, void *msg,
                                                 size_t msgsize)
{
        enum ipc_mem_exec_stage stage;
        struct sk_buff *skb;
        int rc = -EINVAL;
        size_t size;

        /* Test the CP execution state. */
        stage = ipc_mmio_get_exec_stage(ipc_imem->mmio);
        if (stage != IPC_MEM_EXEC_STAGE_BOOT) {
                dev_err(ipc_imem->dev,
                        "Execution_stage: expected BOOT, received = %X", stage);
                goto trigger_chip_info_fail;
        }
        /* Allocate a new sk buf for the chip info. */
        size = ipc_imem->mmio->chip_info_size;
        if (size > IOSM_CHIP_INFO_SIZE_MAX)
                goto trigger_chip_info_fail;

        skb = ipc_pcie_alloc_local_skb(ipc_imem->pcie, GFP_ATOMIC, size);
        if (!skb) {
                dev_err(ipc_imem->dev, "exhausted skbuf kernel DL memory");
                rc = -ENOMEM;
                goto trigger_chip_info_fail;
        }
        /* Copy the chip info characters into the ipc_skb. */
        ipc_mmio_copy_chip_info(ipc_imem->mmio, skb_put(skb, size), size);
        /* First change to the ROM boot phase. */
        dev_dbg(ipc_imem->dev, "execution_stage[%X] eq. BOOT", stage);
        ipc_imem->phase = ipc_imem_phase_update(ipc_imem);
        ipc_imem_sys_devlink_notify_rx(ipc_imem->ipc_devlink, skb);
        rc = 0;
trigger_chip_info_fail:
        return rc;
}

int ipc_imem_devlink_trigger_chip_info(struct iosm_imem *ipc_imem)
{
        return ipc_task_queue_send_task(ipc_imem,
                                        ipc_imem_devlink_trigger_chip_info_cb,
                                        0, NULL, 0, true);
}