// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 *  Copyright (C) 2011-2015 John Crispin <blogic@phrozen.org>
 *  Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
 *  Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>

#include <lantiq_soc.h>

#define XBAR_ALWAYS_LAST        0x430
#define XBAR_FPI_BURST_EN       BIT(1)
#define XBAR_AHB_BURST_EN       BIT(2)

#define RCU_VR9_BE_AHB1S        0x00000008

static int ltq_fpi_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct device_node *np = dev->of_node;
        struct regmap *rcu_regmap;
        void __iomem *xbar_membase;
        u32 rcu_ahb_endianness_reg_offset;
        int ret;

        xbar_membase = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(xbar_membase))
                return PTR_ERR(xbar_membase);

        /* RCU configuration is optional */
        rcu_regmap = syscon_regmap_lookup_by_phandle(np, "lantiq,rcu");
        if (IS_ERR(rcu_regmap))
                return PTR_ERR(rcu_regmap);

        ret = device_property_read_u32(dev, "lantiq,offset-endianness",
                                       &rcu_ahb_endianness_reg_offset);
        if (ret) {
                dev_err(&pdev->dev, "Failed to get RCU reg offset\n");
                return ret;
        }

        ret = regmap_update_bits(rcu_regmap, rcu_ahb_endianness_reg_offset,
                                 RCU_VR9_BE_AHB1S, RCU_VR9_BE_AHB1S);
        if (ret) {
                dev_warn(&pdev->dev,
                         "Failed to configure RCU AHB endianness\n");
                return ret;
        }

        /* disable fpi burst */
        ltq_w32_mask(XBAR_FPI_BURST_EN, 0, xbar_membase + XBAR_ALWAYS_LAST);

        return of_platform_populate(dev->of_node, NULL, NULL, dev);
}

static const struct of_device_id ltq_fpi_match[] = {
        { .compatible = "lantiq,xrx200-fpi" },
        {},
};
MODULE_DEVICE_TABLE(of, ltq_fpi_match);

static struct platform_driver ltq_fpi_driver = {
        .probe = ltq_fpi_probe,
        .driver = {
                .name = "fpi-xway",
                .of_match_table = ltq_fpi_match,
        },
};

module_platform_driver(ltq_fpi_driver);

MODULE_DESCRIPTION("Lantiq FPI bus driver");
MODULE_LICENSE("GPL");