/*
 * Copyright (C) 2013
 *  Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 *  Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <common.h>
#include <init.h>
#include <io.h>
#include <of.h>
#include <of_address.h>
#include <linux/clk.h>

/*
 * Marvell MVEBU SoC id and revision can be read from any PCIe
 * controller port.
 */
u16 soc_devid;
EXPORT_SYMBOL(soc_devid);
u16 soc_revid;
EXPORT_SYMBOL(soc_revid);

static const struct of_device_id mvebu_pcie_of_ids[] = {
	{ .compatible = "marvell,armada-xp-pcie", },
	{ .compatible = "marvell,armada-370-pcie", },
	{ .compatible = "marvell,dove-pcie" },
	{ .compatible = "marvell,kirkwood-pcie" },
	{ },
};

#define PCIE_VEN_DEV_ID		0x000
#define PCIE_REV_ID		0x008
#define  REV_ID_MASK		0xff

static int mvebu_soc_id_init(void)
{
	struct device_node *np, *cnp;
	struct clk *clk;
	void __iomem *base;

	np = of_find_matching_node(NULL, mvebu_pcie_of_ids);
	if (!np)
		return -ENODEV;

	for_each_child_of_node(np, cnp) {
		base = of_iomap(cnp, 0);
		if (!base)
			continue;

		clk = of_clk_get(cnp, 0);
		if (IS_ERR(clk))
			continue;

		clk_enable(clk);
		soc_devid = readl(base + PCIE_VEN_DEV_ID) >> 16;
		soc_revid = readl(base + PCIE_REV_ID) & REV_ID_MASK;
		clk_disable(clk);
		break;
	}

	if (!soc_devid) {
		pr_err("Unable to read SoC id from PCIe ports\n");
		return -EINVAL;
	}

	pr_info("SoC: Marvell %04x rev %d\n", soc_devid, soc_revid);

	return 0;
}
postcore_initcall(mvebu_soc_id_init);