/*
 * Synopsys DWC Ethernet Quality-of-Service v4.10a linux driver
 *
 * Copyright (C) 2016 Joao Pinto <jpinto@synopsys.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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/clk.h>
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/ethtool.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/of_net.h>
#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
#include <linux/stmmac.h>

#include "stmmac_platform.h"

static int dwc_eth_dwmac_config_dt(struct platform_device *pdev,
				   struct plat_stmmacenet_data *plat_dat)
{
	struct device_node *np = pdev->dev.of_node;
	u32 burst_map = 0;
	u32 bit_index = 0;
	u32 a_index = 0;

	if (!plat_dat->axi) {
		plat_dat->axi = kzalloc(sizeof(struct stmmac_axi), GFP_KERNEL);

		if (!plat_dat->axi)
			return -ENOMEM;
	}

	plat_dat->axi->axi_lpi_en = of_property_read_bool(np, "snps,en-lpi");
	if (of_property_read_u32(np, "snps,write-requests",
				 &plat_dat->axi->axi_wr_osr_lmt)) {
		/**
		 * Since the register has a reset value of 1, if property
		 * is missing, default to 1.
		 */
		plat_dat->axi->axi_wr_osr_lmt = 1;
	} else {
		/**
		 * If property exists, to keep the behavior from dwc_eth_qos,
		 * subtract one after parsing.
		 */
		plat_dat->axi->axi_wr_osr_lmt--;
	}

	if (of_property_read_u32(np, "read,read-requests",
				 &plat_dat->axi->axi_rd_osr_lmt)) {
		/**
		 * Since the register has a reset value of 1, if property
		 * is missing, default to 1.
		 */
		plat_dat->axi->axi_rd_osr_lmt = 1;
	} else {
		/**
		 * If property exists, to keep the behavior from dwc_eth_qos,
		 * subtract one after parsing.
		 */
		plat_dat->axi->axi_rd_osr_lmt--;
	}
	of_property_read_u32(np, "snps,burst-map", &burst_map);

	/* converts burst-map bitmask to burst array */
	for (bit_index = 0; bit_index < 7; bit_index++) {
		if (burst_map & (1 << bit_index)) {
			switch (bit_index) {
			case 0:
			plat_dat->axi->axi_blen[a_index] = 4; break;
			case 1:
			plat_dat->axi->axi_blen[a_index] = 8; break;
			case 2:
			plat_dat->axi->axi_blen[a_index] = 16; break;
			case 3:
			plat_dat->axi->axi_blen[a_index] = 32; break;
			case 4:
			plat_dat->axi->axi_blen[a_index] = 64; break;
			case 5:
			plat_dat->axi->axi_blen[a_index] = 128; break;
			case 6:
			plat_dat->axi->axi_blen[a_index] = 256; break;
			default:
			break;
			}
			a_index++;
		}
	}

	/* dwc-qos needs GMAC4, AAL, TSO and PMT */
	plat_dat->has_gmac4 = 1;
	plat_dat->dma_cfg->aal = 1;
	plat_dat->tso_en = 1;
	plat_dat->pmt = 1;

	return 0;
}

static int dwc_eth_dwmac_probe(struct platform_device *pdev)
{
	struct plat_stmmacenet_data *plat_dat;
	struct stmmac_resources stmmac_res;
	struct resource *res;
	int ret;

	memset(&stmmac_res, 0, sizeof(struct stmmac_resources));

	/**
	 * Since stmmac_platform supports name IRQ only, basic platform
	 * resource initialization is done in the glue logic.
	 */
	stmmac_res.irq = platform_get_irq(pdev, 0);
	if (stmmac_res.irq < 0) {
		if (stmmac_res.irq != -EPROBE_DEFER)
			dev_err(&pdev->dev,
				"IRQ configuration information not found\n");

		return stmmac_res.irq;
	}
	stmmac_res.wol_irq = stmmac_res.irq;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	stmmac_res.addr = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(stmmac_res.addr))
		return PTR_ERR(stmmac_res.addr);

	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
	if (IS_ERR(plat_dat))
		return PTR_ERR(plat_dat);

	plat_dat->stmmac_clk = devm_clk_get(&pdev->dev, "apb_pclk");
	if (IS_ERR(plat_dat->stmmac_clk)) {
		dev_err(&pdev->dev, "apb_pclk clock not found.\n");
		ret = PTR_ERR(plat_dat->stmmac_clk);
		plat_dat->stmmac_clk = NULL;
		goto err_remove_config_dt;
	}
	clk_prepare_enable(plat_dat->stmmac_clk);

	plat_dat->pclk = devm_clk_get(&pdev->dev, "phy_ref_clk");
	if (IS_ERR(plat_dat->pclk)) {
		dev_err(&pdev->dev, "phy_ref_clk clock not found.\n");
		ret = PTR_ERR(plat_dat->pclk);
		plat_dat->pclk = NULL;
		goto err_out_clk_dis_phy;
	}
	clk_prepare_enable(plat_dat->pclk);

	ret = dwc_eth_dwmac_config_dt(pdev, plat_dat);
	if (ret)
		goto err_out_clk_dis_aper;

	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
	if (ret)
		goto err_out_clk_dis_aper;

	return 0;

err_out_clk_dis_aper:
	clk_disable_unprepare(plat_dat->pclk);
err_out_clk_dis_phy:
	clk_disable_unprepare(plat_dat->stmmac_clk);
err_remove_config_dt:
	stmmac_remove_config_dt(pdev, plat_dat);

	return ret;
}

static int dwc_eth_dwmac_remove(struct platform_device *pdev)
{
	return stmmac_pltfr_remove(pdev);
}

static const struct of_device_id dwc_eth_dwmac_match[] = {
	{ .compatible = "snps,dwc-qos-ethernet-4.10", },
	{ }
};
MODULE_DEVICE_TABLE(of, dwc_eth_dwmac_match);

static struct platform_driver dwc_eth_dwmac_driver = {
	.probe  = dwc_eth_dwmac_probe,
	.remove = dwc_eth_dwmac_remove,
	.driver = {
		.name           = "dwc-eth-dwmac",
		.of_match_table = dwc_eth_dwmac_match,
	},
};
module_platform_driver(dwc_eth_dwmac_driver);

MODULE_AUTHOR("Joao Pinto <jpinto@synopsys.com>");
MODULE_DESCRIPTION("Synopsys DWC Ethernet Quality-of-Service v4.10a driver");
MODULE_LICENSE("GPL v2");