// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2023 Intel Corporation */
#include <linux/random.h>

#include "adf_admin.h"
#include "adf_common_drv.h"
#include "adf_heartbeat.h"

#define MAX_HB_TICKS 0xFFFFFFFF

static int adf_hb_set_timer_to_max(struct adf_accel_dev *accel_dev)
{
        struct adf_hw_device_data *hw_data = accel_dev->hw_device;

        accel_dev->heartbeat->hb_timer = 0;

        if (hw_data->stop_timer)
                hw_data->stop_timer(accel_dev);

        return adf_send_admin_hb_timer(accel_dev, MAX_HB_TICKS);
}

static void adf_set_hb_counters_fail(struct adf_accel_dev *accel_dev, u32 ae,
                                     u32 thr)
{
        struct hb_cnt_pair *stats = accel_dev->heartbeat->dma.virt_addr;
        struct adf_hw_device_data *hw_device = accel_dev->hw_device;
        const size_t max_aes = hw_device->get_num_aes(hw_device);
        const size_t hb_ctrs = hw_device->num_hb_ctrs;
        size_t thr_id = ae * hb_ctrs + thr;
        u16 num_rsp = stats[thr_id].resp_heartbeat_cnt;

        /*
         * Inject live.req != live.rsp and live.rsp == last.rsp
         * to trigger the heartbeat error detection
         */
        stats[thr_id].req_heartbeat_cnt++;
        stats += (max_aes * hb_ctrs);
        stats[thr_id].resp_heartbeat_cnt = num_rsp;
}

int adf_heartbeat_inject_error(struct adf_accel_dev *accel_dev)
{
        struct adf_hw_device_data *hw_device = accel_dev->hw_device;
        const size_t max_aes = hw_device->get_num_aes(hw_device);
        const size_t hb_ctrs = hw_device->num_hb_ctrs;
        u32 rand, rand_ae, rand_thr;
        unsigned long ae_mask;
        int ret;

        ae_mask = hw_device->ae_mask;

        do {
                /* Ensure we have a valid ae */
                get_random_bytes(&rand, sizeof(rand));
                rand_ae = rand % max_aes;
        } while (!test_bit(rand_ae, &ae_mask));

        get_random_bytes(&rand, sizeof(rand));
        rand_thr = rand % hb_ctrs;

        /* Increase the heartbeat timer to prevent FW updating HB counters */
        ret = adf_hb_set_timer_to_max(accel_dev);
        if (ret)
                return ret;

        /* Configure worker threads to stop processing any packet */
        ret = adf_disable_arb_thd(accel_dev, rand_ae, rand_thr);
        if (ret)
                return ret;

        /* Change HB counters memory to simulate a hang */
        adf_set_hb_counters_fail(accel_dev, rand_ae, rand_thr);

        return 0;
}