// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * Copyright (C) 2013 John Crispin <john@phrozen.org>
 */

#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>

#include <asm/mach-ralink/ralink_regs.h>

#define REG_ILL_ACC_ADDR        0x10
#define REG_ILL_ACC_TYPE        0x14

#define ILL_INT_STATUS          BIT(31)
#define ILL_ACC_WRITE           BIT(30)
#define ILL_ACC_LEN_M           0xff
#define ILL_ACC_OFF_M           0xf
#define ILL_ACC_OFF_S           16
#define ILL_ACC_ID_M            0x7
#define ILL_ACC_ID_S            8

#define DRV_NAME                "ill_acc"

static const char * const ill_acc_ids[] = {
        "cpu", "dma", "ppe", "pdma rx", "pdma tx", "pci/e", "wmac", "usb",
};

static irqreturn_t ill_acc_irq_handler(int irq, void *_priv)
{
        struct device *dev = (struct device *) _priv;
        u32 addr = rt_memc_r32(REG_ILL_ACC_ADDR);
        u32 type = rt_memc_r32(REG_ILL_ACC_TYPE);

        dev_err(dev, "illegal %s access from %s - addr:0x%08x offset:%d len:%d\n",
                (type & ILL_ACC_WRITE) ? ("write") : ("read"),
                ill_acc_ids[(type >> ILL_ACC_ID_S) & ILL_ACC_ID_M],
                addr, (type >> ILL_ACC_OFF_S) & ILL_ACC_OFF_M,
                type & ILL_ACC_LEN_M);

        rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);

        return IRQ_HANDLED;
}

static int __init ill_acc_of_setup(void)
{
        struct platform_device *pdev;
        struct device_node *np;
        int irq;

        /* somehow this driver breaks on RT5350 */
        if (of_machine_is_compatible("ralink,rt5350-soc"))
                return -EINVAL;

        np = of_find_compatible_node(NULL, NULL, "ralink,rt3050-memc");
        if (!np)
                return -EINVAL;

        pdev = of_find_device_by_node(np);
        if (!pdev) {
                pr_err("%pOFn: failed to lookup pdev\n", np);
                of_node_put(np);
                return -EINVAL;
        }

        irq = irq_of_parse_and_map(np, 0);
        of_node_put(np);
        if (!irq) {
                dev_err(&pdev->dev, "failed to get irq\n");
                put_device(&pdev->dev);
                return -EINVAL;
        }

        if (request_irq(irq, ill_acc_irq_handler, 0, "ill_acc", &pdev->dev)) {
                dev_err(&pdev->dev, "failed to request irq\n");
                put_device(&pdev->dev);
                return -EINVAL;
        }

        rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);

        dev_info(&pdev->dev, "irq registered\n");

        return 0;
}

arch_initcall(ill_acc_of_setup);