/*
 * Copyright (c) 2017, Mellanox Technologies. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/module.h>
#include <linux/etherdevice.h>
#include <linux/mlx5/driver.h>

#include "mlx5_core.h"
#include "lib/mlx5.h"
#include "fpga/core.h"
#include "fpga/conn.h"

static const char *const mlx5_fpga_error_strings[] = {
        "Null Syndrome",
        "Corrupted DDR",
        "Flash Timeout",
        "Internal Link Error",
        "Watchdog HW Failure",
        "I2C Failure",
        "Image Changed",
        "Temperature Critical",
};

static struct mlx5_fpga_device *mlx5_fpga_device_alloc(void)
{
        struct mlx5_fpga_device *fdev = NULL;

        fdev = kzalloc(sizeof(*fdev), GFP_KERNEL);
        if (!fdev)
                return NULL;

        spin_lock_init(&fdev->state_lock);
        fdev->state = MLX5_FPGA_STATUS_NONE;
        return fdev;
}

static const char *mlx5_fpga_image_name(enum mlx5_fpga_image image)
{
        switch (image) {
        case MLX5_FPGA_IMAGE_USER:
                return "user";
        case MLX5_FPGA_IMAGE_FACTORY:
                return "factory";
        default:
                return "unknown";
        }
}

static int mlx5_fpga_device_load_check(struct mlx5_fpga_device *fdev)
{
        struct mlx5_fpga_query query;
        int err;

        err = mlx5_fpga_query(fdev->mdev, &query);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to query status: %d\n", err);
                return err;
        }

        fdev->last_admin_image = query.admin_image;
        fdev->last_oper_image = query.oper_image;

        mlx5_fpga_dbg(fdev, "Status %u; Admin image %u; Oper image %u\n",
                      query.status, query.admin_image, query.oper_image);

        if (query.status != MLX5_FPGA_STATUS_SUCCESS) {
                mlx5_fpga_err(fdev, "%s image failed to load; status %u\n",
                              mlx5_fpga_image_name(fdev->last_oper_image),
                              query.status);
                return -EIO;
        }

        return 0;
}

static int mlx5_fpga_device_brb(struct mlx5_fpga_device *fdev)
{
        int err;
        struct mlx5_core_dev *mdev = fdev->mdev;

        err = mlx5_fpga_ctrl_op(mdev, MLX5_FPGA_CTRL_OPERATION_SANDBOX_BYPASS_ON);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to set bypass on: %d\n", err);
                return err;
        }
        err = mlx5_fpga_ctrl_op(mdev, MLX5_FPGA_CTRL_OPERATION_RESET_SANDBOX);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to reset SBU: %d\n", err);
                return err;
        }
        err = mlx5_fpga_ctrl_op(mdev, MLX5_FPGA_CTRL_OPERATION_SANDBOX_BYPASS_OFF);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to set bypass off: %d\n", err);
                return err;
        }
        return 0;
}

int mlx5_fpga_device_start(struct mlx5_core_dev *mdev)
{
        struct mlx5_fpga_device *fdev = mdev->fpga;
        unsigned long flags;
        unsigned int max_num_qps;
        int err;

        if (!fdev)
                return 0;

        err = mlx5_fpga_device_load_check(fdev);
        if (err)
                goto out;

        err = mlx5_fpga_caps(fdev->mdev);
        if (err)
                goto out;

        mlx5_fpga_info(fdev, "device %u; %s image, version %u\n",
                       MLX5_CAP_FPGA(fdev->mdev, fpga_device),
                       mlx5_fpga_image_name(fdev->last_oper_image),
                       MLX5_CAP_FPGA(fdev->mdev, image_version));

        max_num_qps = MLX5_CAP_FPGA(mdev, shell_caps.max_num_qps);
        err = mlx5_core_reserve_gids(mdev, max_num_qps);
        if (err)
                goto out;

        err = mlx5_fpga_conn_device_init(fdev);
        if (err)
                goto err_rsvd_gid;

        if (fdev->last_oper_image == MLX5_FPGA_IMAGE_USER) {
                err = mlx5_fpga_device_brb(fdev);
                if (err)
                        goto err_conn_init;
        }

        goto out;

err_conn_init:
        mlx5_fpga_conn_device_cleanup(fdev);

err_rsvd_gid:
        mlx5_core_unreserve_gids(mdev, max_num_qps);
out:
        spin_lock_irqsave(&fdev->state_lock, flags);
        fdev->state = err ? MLX5_FPGA_STATUS_FAILURE : MLX5_FPGA_STATUS_SUCCESS;
        spin_unlock_irqrestore(&fdev->state_lock, flags);
        return err;
}

int mlx5_fpga_init(struct mlx5_core_dev *mdev)
{
        struct mlx5_fpga_device *fdev = NULL;

        if (!MLX5_CAP_GEN(mdev, fpga)) {
                mlx5_core_dbg(mdev, "FPGA capability not present\n");
                return 0;
        }

        mlx5_core_dbg(mdev, "Initializing FPGA\n");

        fdev = mlx5_fpga_device_alloc();
        if (!fdev)
                return -ENOMEM;

        fdev->mdev = mdev;
        mdev->fpga = fdev;

        return 0;
}

void mlx5_fpga_device_stop(struct mlx5_core_dev *mdev)
{
        struct mlx5_fpga_device *fdev = mdev->fpga;
        unsigned int max_num_qps;
        unsigned long flags;
        int err;

        if (!fdev)
                return;

        spin_lock_irqsave(&fdev->state_lock, flags);
        if (fdev->state != MLX5_FPGA_STATUS_SUCCESS) {
                spin_unlock_irqrestore(&fdev->state_lock, flags);
                return;
        }
        fdev->state = MLX5_FPGA_STATUS_NONE;
        spin_unlock_irqrestore(&fdev->state_lock, flags);

        if (fdev->last_oper_image == MLX5_FPGA_IMAGE_USER) {
                err = mlx5_fpga_ctrl_op(mdev, MLX5_FPGA_CTRL_OPERATION_SANDBOX_BYPASS_ON);
                if (err)
                        mlx5_fpga_err(fdev, "Failed to re-set SBU bypass on: %d\n",
                                      err);
        }

        mlx5_fpga_conn_device_cleanup(fdev);
        max_num_qps = MLX5_CAP_FPGA(mdev, shell_caps.max_num_qps);
        mlx5_core_unreserve_gids(mdev, max_num_qps);
}

void mlx5_fpga_cleanup(struct mlx5_core_dev *mdev)
{
        struct mlx5_fpga_device *fdev = mdev->fpga;

        mlx5_fpga_device_stop(mdev);
        kfree(fdev);
        mdev->fpga = NULL;
}

static const char *mlx5_fpga_syndrome_to_string(u8 syndrome)
{
        if (syndrome < ARRAY_SIZE(mlx5_fpga_error_strings))
                return mlx5_fpga_error_strings[syndrome];
        return "Unknown";
}

void mlx5_fpga_event(struct mlx5_core_dev *mdev, u8 event, void *data)
{
        struct mlx5_fpga_device *fdev = mdev->fpga;
        const char *event_name;
        bool teardown = false;
        unsigned long flags;
        u8 syndrome;

        if (event != MLX5_EVENT_TYPE_FPGA_ERROR) {
                mlx5_fpga_warn_ratelimited(fdev, "Unexpected event %u\n",
                                           event);
                return;
        }

        syndrome = MLX5_GET(fpga_error_event, data, syndrome);
        event_name = mlx5_fpga_syndrome_to_string(syndrome);

        spin_lock_irqsave(&fdev->state_lock, flags);
        switch (fdev->state) {
        case MLX5_FPGA_STATUS_SUCCESS:
                mlx5_fpga_warn(fdev, "Error %u: %s\n", syndrome, event_name);
                teardown = true;
                break;
        default:
                mlx5_fpga_warn_ratelimited(fdev, "Unexpected error event %u: %s\n",
                                           syndrome, event_name);
        }
        spin_unlock_irqrestore(&fdev->state_lock, flags);
        /* We tear-down the card's interfaces and functionality because
         * the FPGA bump-on-the-wire is misbehaving and we lose ability
         * to communicate with the network. User may still be able to
         * recover by re-programming or debugging the FPGA
         */
        if (teardown)
                mlx5_trigger_health_work(fdev->mdev);
}