/*
 * Copyright (c) 2013-2016, NVIDIA CORPORATION.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include <linux/device.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/random.h>

#include <soc/tegra/fuse.h>

#include "fuse.h"

#define FUSE_BEGIN	0x100

/* Tegra30 and later */
#define FUSE_VENDOR_CODE	0x100
#define FUSE_FAB_CODE		0x104
#define FUSE_LOT_CODE_0		0x108
#define FUSE_LOT_CODE_1		0x10c
#define FUSE_WAFER_ID		0x110
#define FUSE_X_COORDINATE	0x114
#define FUSE_Y_COORDINATE	0x118

#define FUSE_HAS_REVISION_INFO	BIT(0)

static u32 tegra30_fuse_read_early(struct tegra_fuse *fuse, unsigned int offset)
{
	return readl_relaxed(fuse->base + FUSE_BEGIN + offset);
}

static u32 tegra30_fuse_read(struct tegra_fuse *fuse, unsigned int offset)
{
	u32 value;
	int err;

	err = clk_prepare_enable(fuse->clk);
	if (err < 0) {
		dev_err(fuse->dev, "failed to enable FUSE clock: %d\n", err);
		return 0;
	}

	value = readl_relaxed(fuse->base + FUSE_BEGIN + offset);

	clk_disable_unprepare(fuse->clk);

	return value;
}

static u32 tegra30_fuse_control_read(struct tegra_fuse *fuse,
	unsigned int offset)
{
	u32 value;
	int err;

	err = clk_prepare_enable(fuse->clk);
	if (err < 0) {
		dev_err(fuse->dev, "failed to enable FUSE clock: %d\n", err);
		return 0;
	}

	value = readl_relaxed(fuse->base + offset);

	clk_disable_unprepare(fuse->clk);

	return value;
}

static int tegra30_fuse_control_write(struct tegra_fuse *fuse, u32 value,
	unsigned int offset)
{
	int err;

	err = clk_prepare_enable(fuse->clk);
	if (err < 0) {
		dev_err(fuse->dev, "failed to enable FUSE clock: %d\n", err);
		return -EIO;
	}

	writel(value, fuse->base + offset);

	clk_disable_unprepare(fuse->clk);

	return 0;
}

static void __init tegra30_fuse_add_randomness(void)
{
	u32 randomness[12];

	randomness[0] = tegra_sku_info.sku_id;
	randomness[1] = tegra_read_straps();
	randomness[2] = tegra_read_chipid();
	randomness[3] = tegra_sku_info.cpu_process_id << 16;
	randomness[3] |= tegra_sku_info.soc_process_id;
	randomness[4] = tegra_sku_info.cpu_speedo_id << 16;
	randomness[4] |= tegra_sku_info.soc_speedo_id;
	randomness[5] = tegra_fuse_read_early(FUSE_VENDOR_CODE);
	randomness[6] = tegra_fuse_read_early(FUSE_FAB_CODE);
	randomness[7] = tegra_fuse_read_early(FUSE_LOT_CODE_0);
	randomness[8] = tegra_fuse_read_early(FUSE_LOT_CODE_1);
	randomness[9] = tegra_fuse_read_early(FUSE_WAFER_ID);
	randomness[10] = tegra_fuse_read_early(FUSE_X_COORDINATE);
	randomness[11] = tegra_fuse_read_early(FUSE_Y_COORDINATE);

	add_device_randomness(randomness, sizeof(randomness));
}

static int tegra30_fuse_write(struct tegra_fuse *fuse, u32 value,
	unsigned int offset)
{
	int err;

	err = clk_prepare_enable(fuse->clk);
	if (err < 0) {
		dev_err(fuse->dev, "failed to enable FUSE clock: %d\n", err);
		return -EIO;
	}

	writel(value, fuse->base + FUSE_BEGIN + offset);

	clk_disable_unprepare(fuse->clk);

	return 0;
}

static void __init tegra30_fuse_init(struct tegra_fuse *fuse)
{
	fuse->read_early = tegra30_fuse_read_early;
	fuse->read = tegra30_fuse_read;
	fuse->write = tegra30_fuse_write;
	fuse->control_read = tegra30_fuse_control_read;
	fuse->control_write = tegra30_fuse_control_write;

	tegra_init_revision();
	if (fuse->soc->speedo_init)
		fuse->soc->speedo_init(&tegra_sku_info);
	tegra30_fuse_add_randomness();
}

static const struct tegra_fuse_info tegra30_fuse_info = {
	.read = tegra30_fuse_read,
	.size = 0x2a4,
	.spare = 0x144,
};

const struct tegra_fuse_soc tegra30_fuse_soc = {
	.init = tegra30_fuse_init,
	.speedo_init = tegra30_init_speedo_data,
	.info = &tegra30_fuse_info,
};

static const struct tegra_fuse_info tegra114_fuse_info = {
	.read = tegra30_fuse_read,
	.size = 0x2a0,
	.spare = 0x180,
};

const struct tegra_fuse_soc tegra114_fuse_soc = {
	.init = tegra30_fuse_init,
	.speedo_init = tegra114_init_speedo_data,
	.info = &tegra114_fuse_info,
};

static const struct tegra_fuse_info tegra124_fuse_info = {
	.read = tegra30_fuse_read,
	.size = 0x300,
	.spare = 0x200,
};

const struct tegra_fuse_soc tegra124_fuse_soc = {
	.init = tegra30_fuse_init,
	.speedo_init = tegra124_init_speedo_data,
	.info = &tegra124_fuse_info,
};

static const struct tegra_fuse_info tegra210_fuse_info = {
	.read = tegra30_fuse_read,
	.write = tegra30_fuse_write,
	.size = 0x300,
	.spare = 0x280,
};

const struct tegra_fuse_soc tegra210_fuse_soc = {
	.init = tegra30_fuse_init,
	.speedo_init = tegra210_init_speedo_data,
	.info = &tegra210_fuse_info,
};

static const struct tegra_fuse_info tegra186_fuse_info = {
	.read = tegra30_fuse_read,
	.write = tegra30_fuse_write,
	.size = 0x300,
	.spare = 0x280,
};

const struct tegra_fuse_soc tegra186_fuse_soc = {
	.init = tegra30_fuse_init,
	.info = &tegra186_fuse_info,
};

const struct tegra_fuse_soc tegra194_fuse_soc = {
	.init = tegra30_fuse_init,
	.info = &tegra186_fuse_info,
};