// SPDX-License-Identifier: GPL-2.0
/*
 * SiFive Platform EDAC Driver
 *
 * Copyright (C) 2018-2022 SiFive, Inc.
 *
 * This driver is partially based on octeon_edac-pc.c
 *
 */
#include <linux/edac.h>
#include <linux/platform_device.h>
#include "edac_module.h"
#include <soc/sifive/sifive_ccache.h>

#define DRVNAME "sifive_edac"

struct sifive_edac_priv {
        struct notifier_block notifier;
        struct edac_device_ctl_info *dci;
};

/*
 * EDAC error callback
 *
 * @event: non-zero if unrecoverable.
 */
static
int ecc_err_event(struct notifier_block *this, unsigned long event, void *ptr)
{
        const char *msg = (char *)ptr;
        struct sifive_edac_priv *p;

        p = container_of(this, struct sifive_edac_priv, notifier);

        if (event == SIFIVE_CCACHE_ERR_TYPE_UE)
                edac_device_handle_ue(p->dci, 0, 0, msg);
        else if (event == SIFIVE_CCACHE_ERR_TYPE_CE)
                edac_device_handle_ce(p->dci, 0, 0, msg);

        return NOTIFY_OK;
}

static int ecc_register(struct platform_device *pdev)
{
        struct sifive_edac_priv *p;

        p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        p->notifier.notifier_call = ecc_err_event;
        platform_set_drvdata(pdev, p);

        p->dci = edac_device_alloc_ctl_info(0, "sifive_ecc", 1, "sifive_ecc",
                                            1, 1, edac_device_alloc_index());
        if (!p->dci)
                return -ENOMEM;

        p->dci->dev = &pdev->dev;
        p->dci->mod_name = "Sifive ECC Manager";
        p->dci->ctl_name = dev_name(&pdev->dev);
        p->dci->dev_name = dev_name(&pdev->dev);

        if (edac_device_add_device(p->dci)) {
                dev_err(p->dci->dev, "failed to register with EDAC core\n");
                goto err;
        }

        register_sifive_ccache_error_notifier(&p->notifier);

        return 0;

err:
        edac_device_free_ctl_info(p->dci);

        return -ENXIO;
}

static int ecc_unregister(struct platform_device *pdev)
{
        struct sifive_edac_priv *p = platform_get_drvdata(pdev);

        unregister_sifive_ccache_error_notifier(&p->notifier);
        edac_device_del_device(&pdev->dev);
        edac_device_free_ctl_info(p->dci);

        return 0;
}

static struct platform_device *sifive_pdev;

static int __init sifive_edac_init(void)
{
        int ret;

        sifive_pdev = platform_device_register_simple(DRVNAME, 0, NULL, 0);
        if (IS_ERR(sifive_pdev))
                return PTR_ERR(sifive_pdev);

        ret = ecc_register(sifive_pdev);
        if (ret)
                platform_device_unregister(sifive_pdev);

        return ret;
}

static void __exit sifive_edac_exit(void)
{
        ecc_unregister(sifive_pdev);
        platform_device_unregister(sifive_pdev);
}

module_init(sifive_edac_init);
module_exit(sifive_edac_exit);

MODULE_AUTHOR("SiFive Inc.");
MODULE_DESCRIPTION("SiFive platform EDAC driver");
MODULE_LICENSE("GPL v2");