drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c - linux - Git at Google

 /*
  * Qualcomm Atheros IPQ806x GMAC glue layer
  *
  * Copyright (C) 2015 The Linux Foundation
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/phy.h>
 #include <linux/regmap.h>
 #include <linux/clk.h>
 #include <linux/reset.h>
 #include <linux/of_net.h>
 #include <linux/mfd/syscon.h>
 #include <linux/stmmac.h>
 #include <linux/of_mdio.h>
 #include <linux/module.h>

 #include "stmmac_platform.h"

 #define NSS_COMMON_CLK_GATE			0x8
 #define NSS_COMMON_CLK_GATE_PTP_EN(x)		BIT(0x10 + x)
 #define NSS_COMMON_CLK_GATE_RGMII_RX_EN(x)	BIT(0x9 + (x * 2))
 #define NSS_COMMON_CLK_GATE_RGMII_TX_EN(x)	BIT(0x8 + (x * 2))
 #define NSS_COMMON_CLK_GATE_GMII_RX_EN(x)	BIT(0x4 + x)
 #define NSS_COMMON_CLK_GATE_GMII_TX_EN(x)	BIT(0x0 + x)

 #define NSS_COMMON_CLK_DIV0			0xC
 #define NSS_COMMON_CLK_DIV_OFFSET(x)		(x * 8)
 #define NSS_COMMON_CLK_DIV_MASK			0x7f

 #define NSS_COMMON_CLK_SRC_CTRL			0x14
 #define NSS_COMMON_CLK_SRC_CTRL_OFFSET(x)	(x)
 /* Mode is coded on 1 bit but is different depending on the MAC ID:
  * MAC0: QSGMII=0 RGMII=1
  * MAC1: QSGMII=0 SGMII=0 RGMII=1
  * MAC2 & MAC3: QSGMII=0 SGMII=1
  */
 #define NSS_COMMON_CLK_SRC_CTRL_RGMII(x)	1
 #define NSS_COMMON_CLK_SRC_CTRL_SGMII(x)	((x >= 2) ? 1 : 0)

 #define NSS_COMMON_GMAC_CTL(x)			(0x30 + (x * 4))
 #define NSS_COMMON_GMAC_CTL_CSYS_REQ		BIT(19)
 #define NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL	BIT(16)
 #define NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET	8
 #define NSS_COMMON_GMAC_CTL_IFG_OFFSET		0

 #define NSS_COMMON_CLK_DIV_RGMII_1000		1
 #define NSS_COMMON_CLK_DIV_RGMII_100		9
 #define NSS_COMMON_CLK_DIV_RGMII_10		99
 #define NSS_COMMON_CLK_DIV_SGMII_1000		0
 #define NSS_COMMON_CLK_DIV_SGMII_100		4
 #define NSS_COMMON_CLK_DIV_SGMII_10		49

 #define QSGMII_PCS_CAL_LCKDT_CTL		0x120
 #define QSGMII_PCS_CAL_LCKDT_CTL_RST		BIT(19)

 /* Only GMAC1/2/3 support SGMII and their CTL register are not contiguous */
 #define QSGMII_PHY_SGMII_CTL(x)			((x == 1) ? 0x134 : \
 						 (0x13c + (4 * (x - 2))))
 #define QSGMII_PHY_CDR_EN			BIT(0)
 #define QSGMII_PHY_RX_FRONT_EN			BIT(1)
 #define QSGMII_PHY_RX_SIGNAL_DETECT_EN		BIT(2)
 #define QSGMII_PHY_TX_DRIVER_EN			BIT(3)
 #define QSGMII_PHY_QSGMII_EN			BIT(7)
 #define QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET	12
 #define QSGMII_PHY_RX_DC_BIAS_OFFSET		18
 #define QSGMII_PHY_RX_INPUT_EQU_OFFSET		20
 #define QSGMII_PHY_CDR_PI_SLEW_OFFSET		22
 #define QSGMII_PHY_TX_DRV_AMP_OFFSET		28

 struct ipq806x_gmac {
 	struct platform_device *pdev;
 	struct regmap *nss_common;
 	struct regmap *qsgmii_csr;
 	uint32_t id;
 	struct clk *core_clk;
 	phy_interface_t phy_mode;
 };

 static int get_clk_div_sgmii(struct ipq806x_gmac *gmac, unsigned int speed)
 {
 	struct device *dev = &gmac->pdev->dev;
 	int div;

 	switch (speed) {
 	case SPEED_1000:
 		div = NSS_COMMON_CLK_DIV_SGMII_1000;
 		break;

 	case SPEED_100:
 		div = NSS_COMMON_CLK_DIV_SGMII_100;
 		break;

 	case SPEED_10:
 		div = NSS_COMMON_CLK_DIV_SGMII_10;
 		break;

 	default:
 		dev_err(dev, "Speed %dMbps not supported in SGMII\n", speed);
 		return -EINVAL;
 	}

 	return div;
 }

 static int get_clk_div_rgmii(struct ipq806x_gmac *gmac, unsigned int speed)
 {
 	struct device *dev = &gmac->pdev->dev;
 	int div;

 	switch (speed) {
 	case SPEED_1000:
 		div = NSS_COMMON_CLK_DIV_RGMII_1000;
 		break;

 	case SPEED_100:
 		div = NSS_COMMON_CLK_DIV_RGMII_100;
 		break;

 	case SPEED_10:
 		div = NSS_COMMON_CLK_DIV_RGMII_10;
 		break;

 	default:
 		dev_err(dev, "Speed %dMbps not supported in RGMII\n", speed);
 		return -EINVAL;
 	}

 	return div;
 }

 static int ipq806x_gmac_set_speed(struct ipq806x_gmac *gmac, unsigned int speed)
 {
 	uint32_t clk_bits, val;
 	int div;

 	switch (gmac->phy_mode) {
 	case PHY_INTERFACE_MODE_RGMII:
 		div = get_clk_div_rgmii(gmac, speed);
 		clk_bits = NSS_COMMON_CLK_GATE_RGMII_RX_EN(gmac->id) |
 			   NSS_COMMON_CLK_GATE_RGMII_TX_EN(gmac->id);
 		break;

 	case PHY_INTERFACE_MODE_SGMII:
 		div = get_clk_div_sgmii(gmac, speed);
 		clk_bits = NSS_COMMON_CLK_GATE_GMII_RX_EN(gmac->id) |
 			   NSS_COMMON_CLK_GATE_GMII_TX_EN(gmac->id);
 		break;

 	default:
 		dev_err(&gmac->pdev->dev, "Unsupported PHY mode: \"%s\"\n",
 			phy_modes(gmac->phy_mode));
 		return -EINVAL;
 	}

 	/* Disable the clocks */
 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
 	val &= ~clk_bits;
 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

 	/* Set the divider */
 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_DIV0, &val);
 	val &= ~(NSS_COMMON_CLK_DIV_MASK
 		 << NSS_COMMON_CLK_DIV_OFFSET(gmac->id));
 	val |= div << NSS_COMMON_CLK_DIV_OFFSET(gmac->id);
 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_DIV0, val);

 	/* Enable the clock back */
 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
 	val |= clk_bits;
 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

 	return 0;
 }

 static int ipq806x_gmac_of_parse(struct ipq806x_gmac *gmac)
 {
 	struct device *dev = &gmac->pdev->dev;

 	gmac->phy_mode = of_get_phy_mode(dev->of_node);
 	if (gmac->phy_mode < 0) {
 		dev_err(dev, "missing phy mode property\n");
 		return -EINVAL;
 	}

 	if (of_property_read_u32(dev->of_node, "qcom,id", &gmac->id) < 0) {
 		dev_err(dev, "missing qcom id property\n");
 		return -EINVAL;
 	}

 	/* The GMACs are called 1 to 4 in the documentation, but to simplify the
 	 * code and keep it consistent with the Linux convention, we'll number
 	 * them from 0 to 3 here.
 	 */
 	if (gmac->id > 3) {
 		dev_err(dev, "invalid gmac id\n");
 		return -EINVAL;
 	}

 	gmac->core_clk = devm_clk_get(dev, "stmmaceth");
 	if (IS_ERR(gmac->core_clk)) {
 		dev_err(dev, "missing stmmaceth clk property\n");
 		return PTR_ERR(gmac->core_clk);
 	}
 	clk_set_rate(gmac->core_clk, 266000000);

 	/* Setup the register map for the nss common registers */
 	gmac->nss_common = syscon_regmap_lookup_by_phandle(dev->of_node,
 							   "qcom,nss-common");
 	if (IS_ERR(gmac->nss_common)) {
 		dev_err(dev, "missing nss-common node\n");
 		return PTR_ERR(gmac->nss_common);
 	}

 	/* Setup the register map for the qsgmii csr registers */
 	gmac->qsgmii_csr = syscon_regmap_lookup_by_phandle(dev->of_node,
 							   "qcom,qsgmii-csr");
 	if (IS_ERR(gmac->qsgmii_csr))
 		dev_err(dev, "missing qsgmii-csr node\n");

 	return PTR_ERR_OR_ZERO(gmac->qsgmii_csr);
 }

 static void ipq806x_gmac_fix_mac_speed(void *priv, unsigned int speed)
 {
 	struct ipq806x_gmac *gmac = priv;

 	ipq806x_gmac_set_speed(gmac, speed);
 }

 static int ipq806x_gmac_probe(struct platform_device *pdev)
 {
 	struct plat_stmmacenet_data *plat_dat;
 	struct stmmac_resources stmmac_res;
 	struct device *dev = &pdev->dev;
 	struct ipq806x_gmac *gmac;
 	int val;
 	int err;

 	val = stmmac_get_platform_resources(pdev, &stmmac_res);
 	if (val)
 		return val;

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

 	gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
 	if (!gmac) {
 		err = -ENOMEM;
 		goto err_remove_config_dt;
 	}

 	gmac->pdev = pdev;

 	err = ipq806x_gmac_of_parse(gmac);
 	if (err) {
 		dev_err(dev, "device tree parsing error\n");
 		goto err_remove_config_dt;
 	}

 	regmap_write(gmac->qsgmii_csr, QSGMII_PCS_CAL_LCKDT_CTL,
 		     QSGMII_PCS_CAL_LCKDT_CTL_RST);

 	/* Inter frame gap is set to 12 */
 	val = 12 << NSS_COMMON_GMAC_CTL_IFG_OFFSET |
 	      12 << NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET;
 	/* We also initiate an AXI low power exit request */
 	val |= NSS_COMMON_GMAC_CTL_CSYS_REQ;
 	switch (gmac->phy_mode) {
 	case PHY_INTERFACE_MODE_RGMII:
 		val |= NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
 		break;
 	case PHY_INTERFACE_MODE_SGMII:
 		val &= ~NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
 		break;
 	default:
 		dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
 			phy_modes(gmac->phy_mode));
 		err = -EINVAL;
 		goto err_remove_config_dt;
 	}
 	regmap_write(gmac->nss_common, NSS_COMMON_GMAC_CTL(gmac->id), val);

 	/* Configure the clock src according to the mode */
 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, &val);
 	val &= ~(1 << NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id));
 	switch (gmac->phy_mode) {
 	case PHY_INTERFACE_MODE_RGMII:
 		val |= NSS_COMMON_CLK_SRC_CTRL_RGMII(gmac->id) <<
 			NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
 		break;
 	case PHY_INTERFACE_MODE_SGMII:
 		val |= NSS_COMMON_CLK_SRC_CTRL_SGMII(gmac->id) <<
 			NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
 		break;
 	default:
 		dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
 			phy_modes(gmac->phy_mode));
 		err = -EINVAL;
 		goto err_remove_config_dt;
 	}
 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, val);

 	/* Enable PTP clock */
 	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
 	val |= NSS_COMMON_CLK_GATE_PTP_EN(gmac->id);
 	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

 	if (gmac->phy_mode == PHY_INTERFACE_MODE_SGMII) {
 		regmap_write(gmac->qsgmii_csr, QSGMII_PHY_SGMII_CTL(gmac->id),
 			     QSGMII_PHY_CDR_EN |
 			     QSGMII_PHY_RX_FRONT_EN |
 			     QSGMII_PHY_RX_SIGNAL_DETECT_EN |
 			     QSGMII_PHY_TX_DRIVER_EN |
 			     QSGMII_PHY_QSGMII_EN |
 			     0x4ul << QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET |
 			     0x3ul << QSGMII_PHY_RX_DC_BIAS_OFFSET |
 			     0x1ul << QSGMII_PHY_RX_INPUT_EQU_OFFSET |
 			     0x2ul << QSGMII_PHY_CDR_PI_SLEW_OFFSET |
 			     0xCul << QSGMII_PHY_TX_DRV_AMP_OFFSET);
 	}

 	plat_dat->has_gmac = true;
 	plat_dat->bsp_priv = gmac;
 	plat_dat->fix_mac_speed = ipq806x_gmac_fix_mac_speed;

 	err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
 	if (err)
 		goto err_remove_config_dt;

 	return 0;

 err_remove_config_dt:
 	stmmac_remove_config_dt(pdev, plat_dat);

 	return err;
 }

 static const struct of_device_id ipq806x_gmac_dwmac_match[] = {
 	{ .compatible = "qcom,ipq806x-gmac" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ipq806x_gmac_dwmac_match);

 static struct platform_driver ipq806x_gmac_dwmac_driver = {
 	.probe = ipq806x_gmac_probe,
 	.remove = stmmac_pltfr_remove,
 	.driver = {
 		.name		= "ipq806x-gmac-dwmac",
 		.pm		= &stmmac_pltfr_pm_ops,
 		.of_match_table	= ipq806x_gmac_dwmac_match,
 	},
 };
 module_platform_driver(ipq806x_gmac_dwmac_driver);

 MODULE_AUTHOR("Mathieu Olivari <mathieu@codeaurora.org>");
 MODULE_DESCRIPTION("Qualcomm Atheros IPQ806x DWMAC specific glue layer");
 MODULE_LICENSE("Dual BSD/GPL");
	/*
	* Qualcomm Atheros IPQ806x GMAC glue layer
	*
	* Copyright (C) 2015 The Linux Foundation
	*
	* Permission to use, copy, modify, and/or distribute this software for any
	* purpose with or without fee is hereby granted, provided that the above
	* copyright notice and this permission notice appear in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#include <linux/device.h>
	#include <linux/platform_device.h>
	#include <linux/phy.h>
	#include <linux/regmap.h>
	#include <linux/clk.h>
	#include <linux/reset.h>
	#include <linux/of_net.h>
	#include <linux/mfd/syscon.h>
	#include <linux/stmmac.h>
	#include <linux/of_mdio.h>
	#include <linux/module.h>

	#include "stmmac_platform.h"

	#define NSS_COMMON_CLK_GATE 0x8
	#define NSS_COMMON_CLK_GATE_PTP_EN(x) BIT(0x10 + x)
	#define NSS_COMMON_CLK_GATE_RGMII_RX_EN(x) BIT(0x9 + (x * 2))
	#define NSS_COMMON_CLK_GATE_RGMII_TX_EN(x) BIT(0x8 + (x * 2))
	#define NSS_COMMON_CLK_GATE_GMII_RX_EN(x) BIT(0x4 + x)
	#define NSS_COMMON_CLK_GATE_GMII_TX_EN(x) BIT(0x0 + x)

	#define NSS_COMMON_CLK_DIV0 0xC
	#define NSS_COMMON_CLK_DIV_OFFSET(x) (x * 8)
	#define NSS_COMMON_CLK_DIV_MASK 0x7f

	#define NSS_COMMON_CLK_SRC_CTRL 0x14
	#define NSS_COMMON_CLK_SRC_CTRL_OFFSET(x) (x)
	/* Mode is coded on 1 bit but is different depending on the MAC ID:
	* MAC0: QSGMII=0 RGMII=1
	* MAC1: QSGMII=0 SGMII=0 RGMII=1
	* MAC2 & MAC3: QSGMII=0 SGMII=1
	*/
	#define NSS_COMMON_CLK_SRC_CTRL_RGMII(x) 1
	#define NSS_COMMON_CLK_SRC_CTRL_SGMII(x) ((x >= 2) ? 1 : 0)

	#define NSS_COMMON_GMAC_CTL(x) (0x30 + (x * 4))
	#define NSS_COMMON_GMAC_CTL_CSYS_REQ BIT(19)
	#define NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL BIT(16)
	#define NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET 8
	#define NSS_COMMON_GMAC_CTL_IFG_OFFSET 0

	#define NSS_COMMON_CLK_DIV_RGMII_1000 1
	#define NSS_COMMON_CLK_DIV_RGMII_100 9
	#define NSS_COMMON_CLK_DIV_RGMII_10 99
	#define NSS_COMMON_CLK_DIV_SGMII_1000 0
	#define NSS_COMMON_CLK_DIV_SGMII_100 4
	#define NSS_COMMON_CLK_DIV_SGMII_10 49

	#define QSGMII_PCS_CAL_LCKDT_CTL 0x120
	#define QSGMII_PCS_CAL_LCKDT_CTL_RST BIT(19)

	/* Only GMAC1/2/3 support SGMII and their CTL register are not contiguous */
	#define QSGMII_PHY_SGMII_CTL(x) ((x == 1) ? 0x134 : \
	(0x13c + (4 * (x - 2))))
	#define QSGMII_PHY_CDR_EN BIT(0)
	#define QSGMII_PHY_RX_FRONT_EN BIT(1)
	#define QSGMII_PHY_RX_SIGNAL_DETECT_EN BIT(2)
	#define QSGMII_PHY_TX_DRIVER_EN BIT(3)
	#define QSGMII_PHY_QSGMII_EN BIT(7)
	#define QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET 12
	#define QSGMII_PHY_RX_DC_BIAS_OFFSET 18
	#define QSGMII_PHY_RX_INPUT_EQU_OFFSET 20
	#define QSGMII_PHY_CDR_PI_SLEW_OFFSET 22
	#define QSGMII_PHY_TX_DRV_AMP_OFFSET 28

	struct ipq806x_gmac {
	struct platform_device *pdev;
	struct regmap *nss_common;
	struct regmap *qsgmii_csr;
	uint32_t id;
	struct clk *core_clk;
	phy_interface_t phy_mode;
	};

	static int get_clk_div_sgmii(struct ipq806x_gmac *gmac, unsigned int speed)
	{
	struct device *dev = &gmac->pdev->dev;
	int div;

	switch (speed) {
	case SPEED_1000:
	div = NSS_COMMON_CLK_DIV_SGMII_1000;
	break;

	case SPEED_100:
	div = NSS_COMMON_CLK_DIV_SGMII_100;
	break;

	case SPEED_10:
	div = NSS_COMMON_CLK_DIV_SGMII_10;
	break;

	default:
	dev_err(dev, "Speed %dMbps not supported in SGMII\n", speed);
	return -EINVAL;
	}

	return div;
	}

	static int get_clk_div_rgmii(struct ipq806x_gmac *gmac, unsigned int speed)
	{
	struct device *dev = &gmac->pdev->dev;
	int div;

	switch (speed) {
	case SPEED_1000:
	div = NSS_COMMON_CLK_DIV_RGMII_1000;
	break;

	case SPEED_100:
	div = NSS_COMMON_CLK_DIV_RGMII_100;
	break;

	case SPEED_10:
	div = NSS_COMMON_CLK_DIV_RGMII_10;
	break;

	default:
	dev_err(dev, "Speed %dMbps not supported in RGMII\n", speed);
	return -EINVAL;
	}

	return div;
	}

	static int ipq806x_gmac_set_speed(struct ipq806x_gmac *gmac, unsigned int speed)
	{
	uint32_t clk_bits, val;
	int div;

	switch (gmac->phy_mode) {
	case PHY_INTERFACE_MODE_RGMII:
	div = get_clk_div_rgmii(gmac, speed);
	clk_bits = NSS_COMMON_CLK_GATE_RGMII_RX_EN(gmac->id) \|
	NSS_COMMON_CLK_GATE_RGMII_TX_EN(gmac->id);
	break;

	case PHY_INTERFACE_MODE_SGMII:
	div = get_clk_div_sgmii(gmac, speed);
	clk_bits = NSS_COMMON_CLK_GATE_GMII_RX_EN(gmac->id) \|
	NSS_COMMON_CLK_GATE_GMII_TX_EN(gmac->id);
	break;

	default:
	dev_err(&gmac->pdev->dev, "Unsupported PHY mode: \"%s\"\n",
	phy_modes(gmac->phy_mode));
	return -EINVAL;
	}

	/* Disable the clocks */
	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
	val &= ~clk_bits;
	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

	/* Set the divider */
	regmap_read(gmac->nss_common, NSS_COMMON_CLK_DIV0, &val);
	val &= ~(NSS_COMMON_CLK_DIV_MASK
	<< NSS_COMMON_CLK_DIV_OFFSET(gmac->id));
	val \|= div << NSS_COMMON_CLK_DIV_OFFSET(gmac->id);
	regmap_write(gmac->nss_common, NSS_COMMON_CLK_DIV0, val);

	/* Enable the clock back */
	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
	val \|= clk_bits;
	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

	return 0;
	}

	static int ipq806x_gmac_of_parse(struct ipq806x_gmac *gmac)
	{
	struct device *dev = &gmac->pdev->dev;

	gmac->phy_mode = of_get_phy_mode(dev->of_node);
	if (gmac->phy_mode < 0) {
	dev_err(dev, "missing phy mode property\n");
	return -EINVAL;
	}

	if (of_property_read_u32(dev->of_node, "qcom,id", &gmac->id) < 0) {
	dev_err(dev, "missing qcom id property\n");
	return -EINVAL;
	}

	/* The GMACs are called 1 to 4 in the documentation, but to simplify the
	* code and keep it consistent with the Linux convention, we'll number
	* them from 0 to 3 here.
	*/
	if (gmac->id > 3) {
	dev_err(dev, "invalid gmac id\n");
	return -EINVAL;
	}

	gmac->core_clk = devm_clk_get(dev, "stmmaceth");
	if (IS_ERR(gmac->core_clk)) {
	dev_err(dev, "missing stmmaceth clk property\n");
	return PTR_ERR(gmac->core_clk);
	}
	clk_set_rate(gmac->core_clk, 266000000);

	/* Setup the register map for the nss common registers */
	gmac->nss_common = syscon_regmap_lookup_by_phandle(dev->of_node,
	"qcom,nss-common");
	if (IS_ERR(gmac->nss_common)) {
	dev_err(dev, "missing nss-common node\n");
	return PTR_ERR(gmac->nss_common);
	}

	/* Setup the register map for the qsgmii csr registers */
	gmac->qsgmii_csr = syscon_regmap_lookup_by_phandle(dev->of_node,
	"qcom,qsgmii-csr");
	if (IS_ERR(gmac->qsgmii_csr))
	dev_err(dev, "missing qsgmii-csr node\n");

	return PTR_ERR_OR_ZERO(gmac->qsgmii_csr);
	}

	static void ipq806x_gmac_fix_mac_speed(void *priv, unsigned int speed)
	{
	struct ipq806x_gmac *gmac = priv;

	ipq806x_gmac_set_speed(gmac, speed);
	}

	static int ipq806x_gmac_probe(struct platform_device *pdev)
	{
	struct plat_stmmacenet_data *plat_dat;
	struct stmmac_resources stmmac_res;
	struct device *dev = &pdev->dev;
	struct ipq806x_gmac *gmac;
	int val;
	int err;

	val = stmmac_get_platform_resources(pdev, &stmmac_res);
	if (val)
	return val;

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

	gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
	if (!gmac) {
	err = -ENOMEM;
	goto err_remove_config_dt;
	}

	gmac->pdev = pdev;

	err = ipq806x_gmac_of_parse(gmac);
	if (err) {
	dev_err(dev, "device tree parsing error\n");
	goto err_remove_config_dt;
	}

	regmap_write(gmac->qsgmii_csr, QSGMII_PCS_CAL_LCKDT_CTL,
	QSGMII_PCS_CAL_LCKDT_CTL_RST);

	/* Inter frame gap is set to 12 */
	val = 12 << NSS_COMMON_GMAC_CTL_IFG_OFFSET \|
	12 << NSS_COMMON_GMAC_CTL_IFG_LIMIT_OFFSET;
	/* We also initiate an AXI low power exit request */
	val \|= NSS_COMMON_GMAC_CTL_CSYS_REQ;
	switch (gmac->phy_mode) {
	case PHY_INTERFACE_MODE_RGMII:
	val \|= NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
	break;
	case PHY_INTERFACE_MODE_SGMII:
	val &= ~NSS_COMMON_GMAC_CTL_PHY_IFACE_SEL;
	break;
	default:
	dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
	phy_modes(gmac->phy_mode));
	err = -EINVAL;
	goto err_remove_config_dt;
	}
	regmap_write(gmac->nss_common, NSS_COMMON_GMAC_CTL(gmac->id), val);

	/* Configure the clock src according to the mode */
	regmap_read(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, &val);
	val &= ~(1 << NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id));
	switch (gmac->phy_mode) {
	case PHY_INTERFACE_MODE_RGMII:
	val \|= NSS_COMMON_CLK_SRC_CTRL_RGMII(gmac->id) <<
	NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
	break;
	case PHY_INTERFACE_MODE_SGMII:
	val \|= NSS_COMMON_CLK_SRC_CTRL_SGMII(gmac->id) <<
	NSS_COMMON_CLK_SRC_CTRL_OFFSET(gmac->id);
	break;
	default:
	dev_err(&pdev->dev, "Unsupported PHY mode: \"%s\"\n",
	phy_modes(gmac->phy_mode));
	err = -EINVAL;
	goto err_remove_config_dt;
	}
	regmap_write(gmac->nss_common, NSS_COMMON_CLK_SRC_CTRL, val);

	/* Enable PTP clock */
	regmap_read(gmac->nss_common, NSS_COMMON_CLK_GATE, &val);
	val \|= NSS_COMMON_CLK_GATE_PTP_EN(gmac->id);
	regmap_write(gmac->nss_common, NSS_COMMON_CLK_GATE, val);

	if (gmac->phy_mode == PHY_INTERFACE_MODE_SGMII) {
	regmap_write(gmac->qsgmii_csr, QSGMII_PHY_SGMII_CTL(gmac->id),
	QSGMII_PHY_CDR_EN \|
	QSGMII_PHY_RX_FRONT_EN \|
	QSGMII_PHY_RX_SIGNAL_DETECT_EN \|
	QSGMII_PHY_TX_DRIVER_EN \|
	QSGMII_PHY_QSGMII_EN \|
	0x4ul << QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET \|
	0x3ul << QSGMII_PHY_RX_DC_BIAS_OFFSET \|
	0x1ul << QSGMII_PHY_RX_INPUT_EQU_OFFSET \|
	0x2ul << QSGMII_PHY_CDR_PI_SLEW_OFFSET \|
	0xCul << QSGMII_PHY_TX_DRV_AMP_OFFSET);
	}

	plat_dat->has_gmac = true;
	plat_dat->bsp_priv = gmac;
	plat_dat->fix_mac_speed = ipq806x_gmac_fix_mac_speed;

	err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
	if (err)
	goto err_remove_config_dt;

	return 0;

	err_remove_config_dt:
	stmmac_remove_config_dt(pdev, plat_dat);

	return err;
	}

	static const struct of_device_id ipq806x_gmac_dwmac_match[] = {
	{ .compatible = "qcom,ipq806x-gmac" },
	{ }
	};
	MODULE_DEVICE_TABLE(of, ipq806x_gmac_dwmac_match);

	static struct platform_driver ipq806x_gmac_dwmac_driver = {
	.probe = ipq806x_gmac_probe,
	.remove = stmmac_pltfr_remove,
	.driver = {
	.name = "ipq806x-gmac-dwmac",
	.pm = &stmmac_pltfr_pm_ops,
	.of_match_table = ipq806x_gmac_dwmac_match,
	},
	};
	module_platform_driver(ipq806x_gmac_dwmac_driver);

	MODULE_AUTHOR("Mathieu Olivari <mathieu@codeaurora.org>");
	MODULE_DESCRIPTION("Qualcomm Atheros IPQ806x DWMAC specific glue layer");
	MODULE_LICENSE("Dual BSD/GPL");