drivers/ata/ahci_dwc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * DWC AHCI SATA Platform driver
  *
  * Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
  */

 #include <linux/ahci_platform.h>
 #include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/clk.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/libata.h>
 #include <linux/log2.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/regmap.h>

 #include "ahci.h"

 #define DRV_NAME "ahci-dwc"

 #define AHCI_DWC_FBS_PMPN_MAX		15

 /* DWC AHCI SATA controller specific registers */
 #define AHCI_DWC_HOST_OOBR		0xbc
 #define AHCI_DWC_HOST_OOB_WE		BIT(31)
 #define AHCI_DWC_HOST_CWMIN_MASK	GENMASK(30, 24)
 #define AHCI_DWC_HOST_CWMAX_MASK	GENMASK(23, 16)
 #define AHCI_DWC_HOST_CIMIN_MASK	GENMASK(15, 8)
 #define AHCI_DWC_HOST_CIMAX_MASK	GENMASK(7, 0)

 #define AHCI_DWC_HOST_GPCR		0xd0
 #define AHCI_DWC_HOST_GPSR		0xd4

 #define AHCI_DWC_HOST_TIMER1MS		0xe0
 #define AHCI_DWC_HOST_TIMV_MASK		GENMASK(19, 0)

 #define AHCI_DWC_HOST_GPARAM1R		0xe8
 #define AHCI_DWC_HOST_ALIGN_M		BIT(31)
 #define AHCI_DWC_HOST_RX_BUFFER		BIT(30)
 #define AHCI_DWC_HOST_PHY_DATA_MASK	GENMASK(29, 28)
 #define AHCI_DWC_HOST_PHY_RST		BIT(27)
 #define AHCI_DWC_HOST_PHY_CTRL_MASK	GENMASK(26, 21)
 #define AHCI_DWC_HOST_PHY_STAT_MASK	GENMASK(20, 15)
 #define AHCI_DWC_HOST_LATCH_M		BIT(14)
 #define AHCI_DWC_HOST_PHY_TYPE_MASK	GENMASK(13, 11)
 #define AHCI_DWC_HOST_RET_ERR		BIT(10)
 #define AHCI_DWC_HOST_AHB_ENDIAN_MASK	GENMASK(9, 8)
 #define AHCI_DWC_HOST_S_HADDR		BIT(7)
 #define AHCI_DWC_HOST_M_HADDR		BIT(6)
 #define AHCI_DWC_HOST_S_HDATA_MASK	GENMASK(5, 3)
 #define AHCI_DWC_HOST_M_HDATA_MASK	GENMASK(2, 0)

 #define AHCI_DWC_HOST_GPARAM2R		0xec
 #define AHCI_DWC_HOST_FBS_MEM_S		BIT(19)
 #define AHCI_DWC_HOST_FBS_PMPN_MASK	GENMASK(17, 16)
 #define AHCI_DWC_HOST_FBS_SUP		BIT(15)
 #define AHCI_DWC_HOST_DEV_CP		BIT(14)
 #define AHCI_DWC_HOST_DEV_MP		BIT(13)
 #define AHCI_DWC_HOST_ENCODE_M		BIT(12)
 #define AHCI_DWC_HOST_RXOOB_CLK_M	BIT(11)
 #define AHCI_DWC_HOST_RXOOB_M		BIT(10)
 #define AHCI_DWC_HOST_TXOOB_M		BIT(9)
 #define AHCI_DWC_HOST_RXOOB_M		BIT(10)
 #define AHCI_DWC_HOST_RXOOB_CLK_MASK	GENMASK(8, 0)

 #define AHCI_DWC_HOST_PPARAMR		0xf0
 #define AHCI_DWC_HOST_TX_MEM_M		BIT(11)
 #define AHCI_DWC_HOST_TX_MEM_S		BIT(10)
 #define AHCI_DWC_HOST_RX_MEM_M		BIT(9)
 #define AHCI_DWC_HOST_RX_MEM_S		BIT(8)
 #define AHCI_DWC_HOST_TXFIFO_DEPTH	GENMASK(7, 4)
 #define AHCI_DWC_HOST_RXFIFO_DEPTH	GENMASK(3, 0)

 #define AHCI_DWC_HOST_TESTR		0xf4
 #define AHCI_DWC_HOST_PSEL_MASK		GENMASK(18, 16)
 #define AHCI_DWC_HOST_TEST_IF		BIT(0)

 #define AHCI_DWC_HOST_VERSIONR		0xf8
 #define AHCI_DWC_HOST_IDR		0xfc

 #define AHCI_DWC_PORT_DMACR		0x70
 #define AHCI_DWC_PORT_RXABL_MASK	GENMASK(15, 12)
 #define AHCI_DWC_PORT_TXABL_MASK	GENMASK(11, 8)
 #define AHCI_DWC_PORT_RXTS_MASK		GENMASK(7, 4)
 #define AHCI_DWC_PORT_TXTS_MASK		GENMASK(3, 0)
 #define AHCI_DWC_PORT_PHYCR		0x74
 #define AHCI_DWC_PORT_PHYSR		0x78

 /* Baikal-T1 AHCI SATA specific registers */
 #define AHCI_BT1_HOST_PHYCR		AHCI_DWC_HOST_GPCR
 #define AHCI_BT1_HOST_MPLM_MASK		GENMASK(29, 23)
 #define AHCI_BT1_HOST_LOSDT_MASK	GENMASK(22, 20)
 #define AHCI_BT1_HOST_CRR		BIT(19)
 #define AHCI_BT1_HOST_CRW		BIT(18)
 #define AHCI_BT1_HOST_CRCD		BIT(17)
 #define AHCI_BT1_HOST_CRCA		BIT(16)
 #define AHCI_BT1_HOST_CRDI_MASK		GENMASK(15, 0)

 #define AHCI_BT1_HOST_PHYSR		AHCI_DWC_HOST_GPSR
 #define AHCI_BT1_HOST_CRA		BIT(16)
 #define AHCI_BT1_HOST_CRDO_MASK		GENMASK(15, 0)

 struct ahci_dwc_plat_data {
 	unsigned int pflags;
 	unsigned int hflags;
 	int (*init)(struct ahci_host_priv *hpriv);
 	int (*reinit)(struct ahci_host_priv *hpriv);
 	void (*clear)(struct ahci_host_priv *hpriv);
 };

 struct ahci_dwc_host_priv {
 	const struct ahci_dwc_plat_data *pdata;
 	struct platform_device *pdev;

 	u32 timv;
 	u32 dmacr[AHCI_MAX_PORTS];
 };

 static int ahci_bt1_init(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	int ret;

 	/* APB, application and reference clocks are required */
 	if (!ahci_platform_find_clk(hpriv, "pclk") ||
 	    !ahci_platform_find_clk(hpriv, "aclk") ||
 	    !ahci_platform_find_clk(hpriv, "ref")) {
 		dev_err(&dpriv->pdev->dev, "No system clocks specified\n");
 		return -EINVAL;
 	}

 	/*
 	 * Fully reset the SATA AXI and ref clocks domain to ensure the state
 	 * machine is working from scratch especially if the reference clocks
 	 * source has been changed.
 	 */
 	ret = ahci_platform_assert_rsts(hpriv);
 	if (ret) {
 		dev_err(&dpriv->pdev->dev, "Couldn't assert the resets\n");
 		return ret;
 	}

 	ret = ahci_platform_deassert_rsts(hpriv);
 	if (ret) {
 		dev_err(&dpriv->pdev->dev, "Couldn't de-assert the resets\n");
 		return ret;
 	}

 	return 0;
 }

 static struct ahci_host_priv *ahci_dwc_get_resources(struct platform_device *pdev)
 {
 	struct ahci_dwc_host_priv *dpriv;
 	struct ahci_host_priv *hpriv;

 	dpriv = devm_kzalloc(&pdev->dev, sizeof(*dpriv), GFP_KERNEL);
 	if (!dpriv)
 		return ERR_PTR(-ENOMEM);

 	dpriv->pdev = pdev;
 	dpriv->pdata = device_get_match_data(&pdev->dev);
 	if (!dpriv->pdata)
 		return ERR_PTR(-EINVAL);

 	hpriv = ahci_platform_get_resources(pdev, dpriv->pdata->pflags);
 	if (IS_ERR(hpriv))
 		return hpriv;

 	hpriv->flags |= dpriv->pdata->hflags;
 	hpriv->plat_data = (void *)dpriv;

 	return hpriv;
 }

 static void ahci_dwc_check_cap(struct ahci_host_priv *hpriv)
 {
 	unsigned long port_map = hpriv->saved_port_map | hpriv->mask_port_map;
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	bool dev_mp, dev_cp, fbs_sup;
 	unsigned int fbs_pmp;
 	u32 param;
 	int i;

 	param = readl(hpriv->mmio + AHCI_DWC_HOST_GPARAM2R);
 	dev_mp = !!(param & AHCI_DWC_HOST_DEV_MP);
 	dev_cp = !!(param & AHCI_DWC_HOST_DEV_CP);
 	fbs_sup = !!(param & AHCI_DWC_HOST_FBS_SUP);
 	fbs_pmp = 5 * FIELD_GET(AHCI_DWC_HOST_FBS_PMPN_MASK, param);

 	if (!dev_mp && hpriv->saved_cap & HOST_CAP_MPS) {
 		dev_warn(&dpriv->pdev->dev, "MPS is unsupported\n");
 		hpriv->saved_cap &= ~HOST_CAP_MPS;
 	}


 	if (fbs_sup && fbs_pmp < AHCI_DWC_FBS_PMPN_MAX) {
 		dev_warn(&dpriv->pdev->dev, "PMPn is limited up to %u ports\n",
 			 fbs_pmp);
 	}

 	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
 		if (!dev_mp && hpriv->saved_port_cap[i] & PORT_CMD_MPSP) {
 			dev_warn(&dpriv->pdev->dev, "MPS incapable port %d\n", i);
 			hpriv->saved_port_cap[i] &= ~PORT_CMD_MPSP;
 		}

 		if (!dev_cp && hpriv->saved_port_cap[i] & PORT_CMD_CPD) {
 			dev_warn(&dpriv->pdev->dev, "CPD incapable port %d\n", i);
 			hpriv->saved_port_cap[i] &= ~PORT_CMD_CPD;
 		}

 		if (!fbs_sup && hpriv->saved_port_cap[i] & PORT_CMD_FBSCP) {
 			dev_warn(&dpriv->pdev->dev, "FBS incapable port %d\n", i);
 			hpriv->saved_port_cap[i] &= ~PORT_CMD_FBSCP;
 		}
 	}
 }

 static void ahci_dwc_init_timer(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	unsigned long rate;
 	struct clk *aclk;
 	u32 cap, cap2;

 	/* 1ms tick is generated only for the CCC or DevSleep features */
 	cap = readl(hpriv->mmio + HOST_CAP);
 	cap2 = readl(hpriv->mmio + HOST_CAP2);
 	if (!(cap & HOST_CAP_CCC) && !(cap2 & HOST_CAP2_SDS))
 		return;

 	/*
 	 * Tick is generated based on the AXI/AHB application clocks signal
 	 * so we need to be sure in the clock we are going to use.
 	 */
 	aclk = ahci_platform_find_clk(hpriv, "aclk");
 	if (!aclk)
 		return;

 	/* 1ms timer interval is set as TIMV = AMBA_FREQ[MHZ] * 1000 */
 	dpriv->timv = readl(hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
 	dpriv->timv = FIELD_GET(AHCI_DWC_HOST_TIMV_MASK, dpriv->timv);
 	rate = clk_get_rate(aclk) / 1000UL;
 	if (rate == dpriv->timv)
 		return;

 	dev_info(&dpriv->pdev->dev, "Update CCC/DevSlp timer for Fapp %lu MHz\n",
 		 rate / 1000UL);
 	dpriv->timv = FIELD_PREP(AHCI_DWC_HOST_TIMV_MASK, rate);
 	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
 }

 static int ahci_dwc_init_dmacr(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	struct device_node *child;
 	void __iomem *port_mmio;
 	u32 port, dmacr, ts;

 	/*
 	 * Update the DMA Tx/Rx transaction sizes in accordance with the
 	 * platform setup. Note values exceeding maximal or minimal limits will
 	 * be automatically clamped. Also note the register isn't affected by
 	 * the HBA global reset so we can freely initialize it once until the
 	 * next system reset.
 	 */
 	for_each_child_of_node(dpriv->pdev->dev.of_node, child) {
 		if (!of_device_is_available(child))
 			continue;

 		if (of_property_read_u32(child, "reg", &port)) {
 			of_node_put(child);
 			return -EINVAL;
 		}

 		port_mmio = __ahci_port_base(hpriv, port);
 		dmacr = readl(port_mmio + AHCI_DWC_PORT_DMACR);

 		if (!of_property_read_u32(child, "snps,tx-ts-max", &ts)) {
 			ts = ilog2(ts);
 			dmacr &= ~AHCI_DWC_PORT_TXTS_MASK;
 			dmacr |= FIELD_PREP(AHCI_DWC_PORT_TXTS_MASK, ts);
 		}

 		if (!of_property_read_u32(child, "snps,rx-ts-max", &ts)) {
 			ts = ilog2(ts);
 			dmacr &= ~AHCI_DWC_PORT_RXTS_MASK;
 			dmacr |= FIELD_PREP(AHCI_DWC_PORT_RXTS_MASK, ts);
 		}

 		writel(dmacr, port_mmio + AHCI_DWC_PORT_DMACR);
 		dpriv->dmacr[port] = dmacr;
 	}

 	return 0;
 }

 static int ahci_dwc_init_host(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	int rc;

 	rc = ahci_platform_enable_resources(hpriv);
 	if (rc)
 		return rc;

 	if (dpriv->pdata->init) {
 		rc = dpriv->pdata->init(hpriv);
 		if (rc)
 			goto err_disable_resources;
 	}

 	ahci_dwc_check_cap(hpriv);

 	ahci_dwc_init_timer(hpriv);

 	rc = ahci_dwc_init_dmacr(hpriv);
 	if (rc)
 		goto err_clear_platform;

 	return 0;

 err_clear_platform:
 	if (dpriv->pdata->clear)
 		dpriv->pdata->clear(hpriv);

 err_disable_resources:
 	ahci_platform_disable_resources(hpriv);

 	return rc;
 }

 static int ahci_dwc_reinit_host(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
 	unsigned long port_map = hpriv->port_map;
 	void __iomem *port_mmio;
 	int i, rc;

 	rc = ahci_platform_enable_resources(hpriv);
 	if (rc)
 		return rc;

 	if (dpriv->pdata->reinit) {
 		rc = dpriv->pdata->reinit(hpriv);
 		if (rc)
 			goto err_disable_resources;
 	}

 	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);

 	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
 		port_mmio = __ahci_port_base(hpriv, i);
 		writel(dpriv->dmacr[i], port_mmio + AHCI_DWC_PORT_DMACR);
 	}

 	return 0;

 err_disable_resources:
 	ahci_platform_disable_resources(hpriv);

 	return rc;
 }

 static void ahci_dwc_clear_host(struct ahci_host_priv *hpriv)
 {
 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;

 	if (dpriv->pdata->clear)
 		dpriv->pdata->clear(hpriv);

 	ahci_platform_disable_resources(hpriv);
 }

 static void ahci_dwc_stop_host(struct ata_host *host)
 {
 	struct ahci_host_priv *hpriv = host->private_data;

 	ahci_dwc_clear_host(hpriv);
 }

 static struct ata_port_operations ahci_dwc_port_ops = {
 	.inherits	= &ahci_platform_ops,
 	.host_stop	= ahci_dwc_stop_host,
 };

 static const struct ata_port_info ahci_dwc_port_info = {
 	.flags		= AHCI_FLAG_COMMON,
 	.pio_mask	= ATA_PIO4,
 	.udma_mask	= ATA_UDMA6,
 	.port_ops	= &ahci_dwc_port_ops,
 };

 static const struct scsi_host_template ahci_dwc_scsi_info = {
 	AHCI_SHT(DRV_NAME),
 };

 static int ahci_dwc_probe(struct platform_device *pdev)
 {
 	struct ahci_host_priv *hpriv;
 	int rc;

 	hpriv = ahci_dwc_get_resources(pdev);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);

 	rc = ahci_dwc_init_host(hpriv);
 	if (rc)
 		return rc;

 	rc = ahci_platform_init_host(pdev, hpriv, &ahci_dwc_port_info,
 				     &ahci_dwc_scsi_info);
 	if (rc)
 		goto err_clear_host;

 	return 0;

 err_clear_host:
 	ahci_dwc_clear_host(hpriv);

 	return rc;
 }

 static int ahci_dwc_suspend(struct device *dev)
 {
 	struct ata_host *host = dev_get_drvdata(dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	int rc;

 	rc = ahci_platform_suspend_host(dev);
 	if (rc)
 		return rc;

 	ahci_dwc_clear_host(hpriv);

 	return 0;
 }

 static int ahci_dwc_resume(struct device *dev)
 {
 	struct ata_host *host = dev_get_drvdata(dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	int rc;

 	rc = ahci_dwc_reinit_host(hpriv);
 	if (rc)
 		return rc;

 	return ahci_platform_resume_host(dev);
 }

 static DEFINE_SIMPLE_DEV_PM_OPS(ahci_dwc_pm_ops, ahci_dwc_suspend,
 				ahci_dwc_resume);

 static struct ahci_dwc_plat_data ahci_dwc_plat = {
 	.pflags = AHCI_PLATFORM_GET_RESETS,
 };

 static struct ahci_dwc_plat_data ahci_bt1_plat = {
 	.pflags = AHCI_PLATFORM_GET_RESETS | AHCI_PLATFORM_RST_TRIGGER,
 	.init = ahci_bt1_init,
 };

 static const struct of_device_id ahci_dwc_of_match[] = {
 	{ .compatible = "snps,dwc-ahci", &ahci_dwc_plat },
 	{ .compatible = "snps,spear-ahci", &ahci_dwc_plat },
 	{ .compatible = "baikal,bt1-ahci", &ahci_bt1_plat },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ahci_dwc_of_match);

 static struct platform_driver ahci_dwc_driver = {
 	.probe = ahci_dwc_probe,
 	.remove = ata_platform_remove_one,
 	.shutdown = ahci_platform_shutdown,
 	.driver = {
 		.name = DRV_NAME,
 		.of_match_table = ahci_dwc_of_match,
 		.pm = &ahci_dwc_pm_ops,
 	},
 };
 module_platform_driver(ahci_dwc_driver);

 MODULE_DESCRIPTION("DWC AHCI SATA platform driver");
 MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* DWC AHCI SATA Platform driver
	*
	* Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
	*/

	#include <linux/ahci_platform.h>
	#include <linux/bitfield.h>
	#include <linux/bits.h>
	#include <linux/clk.h>
	#include <linux/device.h>
	#include <linux/kernel.h>
	#include <linux/libata.h>
	#include <linux/log2.h>
	#include <linux/mfd/syscon.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm.h>
	#include <linux/regmap.h>

	#include "ahci.h"

	#define DRV_NAME "ahci-dwc"

	#define AHCI_DWC_FBS_PMPN_MAX 15

	/* DWC AHCI SATA controller specific registers */
	#define AHCI_DWC_HOST_OOBR 0xbc
	#define AHCI_DWC_HOST_OOB_WE BIT(31)
	#define AHCI_DWC_HOST_CWMIN_MASK GENMASK(30, 24)
	#define AHCI_DWC_HOST_CWMAX_MASK GENMASK(23, 16)
	#define AHCI_DWC_HOST_CIMIN_MASK GENMASK(15, 8)
	#define AHCI_DWC_HOST_CIMAX_MASK GENMASK(7, 0)

	#define AHCI_DWC_HOST_GPCR 0xd0
	#define AHCI_DWC_HOST_GPSR 0xd4

	#define AHCI_DWC_HOST_TIMER1MS 0xe0
	#define AHCI_DWC_HOST_TIMV_MASK GENMASK(19, 0)

	#define AHCI_DWC_HOST_GPARAM1R 0xe8
	#define AHCI_DWC_HOST_ALIGN_M BIT(31)
	#define AHCI_DWC_HOST_RX_BUFFER BIT(30)
	#define AHCI_DWC_HOST_PHY_DATA_MASK GENMASK(29, 28)
	#define AHCI_DWC_HOST_PHY_RST BIT(27)
	#define AHCI_DWC_HOST_PHY_CTRL_MASK GENMASK(26, 21)
	#define AHCI_DWC_HOST_PHY_STAT_MASK GENMASK(20, 15)
	#define AHCI_DWC_HOST_LATCH_M BIT(14)
	#define AHCI_DWC_HOST_PHY_TYPE_MASK GENMASK(13, 11)
	#define AHCI_DWC_HOST_RET_ERR BIT(10)
	#define AHCI_DWC_HOST_AHB_ENDIAN_MASK GENMASK(9, 8)
	#define AHCI_DWC_HOST_S_HADDR BIT(7)
	#define AHCI_DWC_HOST_M_HADDR BIT(6)
	#define AHCI_DWC_HOST_S_HDATA_MASK GENMASK(5, 3)
	#define AHCI_DWC_HOST_M_HDATA_MASK GENMASK(2, 0)

	#define AHCI_DWC_HOST_GPARAM2R 0xec
	#define AHCI_DWC_HOST_FBS_MEM_S BIT(19)
	#define AHCI_DWC_HOST_FBS_PMPN_MASK GENMASK(17, 16)
	#define AHCI_DWC_HOST_FBS_SUP BIT(15)
	#define AHCI_DWC_HOST_DEV_CP BIT(14)
	#define AHCI_DWC_HOST_DEV_MP BIT(13)
	#define AHCI_DWC_HOST_ENCODE_M BIT(12)
	#define AHCI_DWC_HOST_RXOOB_CLK_M BIT(11)
	#define AHCI_DWC_HOST_RXOOB_M BIT(10)
	#define AHCI_DWC_HOST_TXOOB_M BIT(9)
	#define AHCI_DWC_HOST_RXOOB_M BIT(10)
	#define AHCI_DWC_HOST_RXOOB_CLK_MASK GENMASK(8, 0)

	#define AHCI_DWC_HOST_PPARAMR 0xf0
	#define AHCI_DWC_HOST_TX_MEM_M BIT(11)
	#define AHCI_DWC_HOST_TX_MEM_S BIT(10)
	#define AHCI_DWC_HOST_RX_MEM_M BIT(9)
	#define AHCI_DWC_HOST_RX_MEM_S BIT(8)
	#define AHCI_DWC_HOST_TXFIFO_DEPTH GENMASK(7, 4)
	#define AHCI_DWC_HOST_RXFIFO_DEPTH GENMASK(3, 0)

	#define AHCI_DWC_HOST_TESTR 0xf4
	#define AHCI_DWC_HOST_PSEL_MASK GENMASK(18, 16)
	#define AHCI_DWC_HOST_TEST_IF BIT(0)

	#define AHCI_DWC_HOST_VERSIONR 0xf8
	#define AHCI_DWC_HOST_IDR 0xfc

	#define AHCI_DWC_PORT_DMACR 0x70
	#define AHCI_DWC_PORT_RXABL_MASK GENMASK(15, 12)
	#define AHCI_DWC_PORT_TXABL_MASK GENMASK(11, 8)
	#define AHCI_DWC_PORT_RXTS_MASK GENMASK(7, 4)
	#define AHCI_DWC_PORT_TXTS_MASK GENMASK(3, 0)
	#define AHCI_DWC_PORT_PHYCR 0x74
	#define AHCI_DWC_PORT_PHYSR 0x78

	/* Baikal-T1 AHCI SATA specific registers */
	#define AHCI_BT1_HOST_PHYCR AHCI_DWC_HOST_GPCR
	#define AHCI_BT1_HOST_MPLM_MASK GENMASK(29, 23)
	#define AHCI_BT1_HOST_LOSDT_MASK GENMASK(22, 20)
	#define AHCI_BT1_HOST_CRR BIT(19)
	#define AHCI_BT1_HOST_CRW BIT(18)
	#define AHCI_BT1_HOST_CRCD BIT(17)
	#define AHCI_BT1_HOST_CRCA BIT(16)
	#define AHCI_BT1_HOST_CRDI_MASK GENMASK(15, 0)

	#define AHCI_BT1_HOST_PHYSR AHCI_DWC_HOST_GPSR
	#define AHCI_BT1_HOST_CRA BIT(16)
	#define AHCI_BT1_HOST_CRDO_MASK GENMASK(15, 0)

	struct ahci_dwc_plat_data {
	unsigned int pflags;
	unsigned int hflags;
	int (init)(struct ahci_host_priv hpriv);
	int (reinit)(struct ahci_host_priv hpriv);
	void (clear)(struct ahci_host_priv hpriv);
	};

	struct ahci_dwc_host_priv {
	const struct ahci_dwc_plat_data *pdata;
	struct platform_device *pdev;

	u32 timv;
	u32 dmacr[AHCI_MAX_PORTS];
	};

	static int ahci_bt1_init(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	int ret;

	/* APB, application and reference clocks are required */
	if (!ahci_platform_find_clk(hpriv, "pclk") \|\|
	!ahci_platform_find_clk(hpriv, "aclk") \|\|
	!ahci_platform_find_clk(hpriv, "ref")) {
	dev_err(&dpriv->pdev->dev, "No system clocks specified\n");
	return -EINVAL;
	}

	/*
	* Fully reset the SATA AXI and ref clocks domain to ensure the state
	* machine is working from scratch especially if the reference clocks
	* source has been changed.
	*/
	ret = ahci_platform_assert_rsts(hpriv);
	if (ret) {
	dev_err(&dpriv->pdev->dev, "Couldn't assert the resets\n");
	return ret;
	}

	ret = ahci_platform_deassert_rsts(hpriv);
	if (ret) {
	dev_err(&dpriv->pdev->dev, "Couldn't de-assert the resets\n");
	return ret;
	}

	return 0;
	}

	static struct ahci_host_priv ahci_dwc_get_resources(struct platform_device pdev)
	{
	struct ahci_dwc_host_priv *dpriv;
	struct ahci_host_priv *hpriv;

	dpriv = devm_kzalloc(&pdev->dev, sizeof(*dpriv), GFP_KERNEL);
	if (!dpriv)
	return ERR_PTR(-ENOMEM);

	dpriv->pdev = pdev;
	dpriv->pdata = device_get_match_data(&pdev->dev);
	if (!dpriv->pdata)
	return ERR_PTR(-EINVAL);

	hpriv = ahci_platform_get_resources(pdev, dpriv->pdata->pflags);
	if (IS_ERR(hpriv))
	return hpriv;

	hpriv->flags \|= dpriv->pdata->hflags;
	hpriv->plat_data = (void *)dpriv;

	return hpriv;
	}

	static void ahci_dwc_check_cap(struct ahci_host_priv *hpriv)
	{
	unsigned long port_map = hpriv->saved_port_map \| hpriv->mask_port_map;
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	bool dev_mp, dev_cp, fbs_sup;
	unsigned int fbs_pmp;
	u32 param;
	int i;

	param = readl(hpriv->mmio + AHCI_DWC_HOST_GPARAM2R);
	dev_mp = !!(param & AHCI_DWC_HOST_DEV_MP);
	dev_cp = !!(param & AHCI_DWC_HOST_DEV_CP);
	fbs_sup = !!(param & AHCI_DWC_HOST_FBS_SUP);
	fbs_pmp = 5 * FIELD_GET(AHCI_DWC_HOST_FBS_PMPN_MASK, param);

	if (!dev_mp && hpriv->saved_cap & HOST_CAP_MPS) {
	dev_warn(&dpriv->pdev->dev, "MPS is unsupported\n");
	hpriv->saved_cap &= ~HOST_CAP_MPS;
	}


	if (fbs_sup && fbs_pmp < AHCI_DWC_FBS_PMPN_MAX) {
	dev_warn(&dpriv->pdev->dev, "PMPn is limited up to %u ports\n",
	fbs_pmp);
	}

	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
	if (!dev_mp && hpriv->saved_port_cap[i] & PORT_CMD_MPSP) {
	dev_warn(&dpriv->pdev->dev, "MPS incapable port %d\n", i);
	hpriv->saved_port_cap[i] &= ~PORT_CMD_MPSP;
	}

	if (!dev_cp && hpriv->saved_port_cap[i] & PORT_CMD_CPD) {
	dev_warn(&dpriv->pdev->dev, "CPD incapable port %d\n", i);
	hpriv->saved_port_cap[i] &= ~PORT_CMD_CPD;
	}

	if (!fbs_sup && hpriv->saved_port_cap[i] & PORT_CMD_FBSCP) {
	dev_warn(&dpriv->pdev->dev, "FBS incapable port %d\n", i);
	hpriv->saved_port_cap[i] &= ~PORT_CMD_FBSCP;
	}
	}
	}

	static void ahci_dwc_init_timer(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	unsigned long rate;
	struct clk *aclk;
	u32 cap, cap2;

	/* 1ms tick is generated only for the CCC or DevSleep features */
	cap = readl(hpriv->mmio + HOST_CAP);
	cap2 = readl(hpriv->mmio + HOST_CAP2);
	if (!(cap & HOST_CAP_CCC) && !(cap2 & HOST_CAP2_SDS))
	return;

	/*
	* Tick is generated based on the AXI/AHB application clocks signal
	* so we need to be sure in the clock we are going to use.
	*/
	aclk = ahci_platform_find_clk(hpriv, "aclk");
	if (!aclk)
	return;

	/* 1ms timer interval is set as TIMV = AMBA_FREQ[MHZ] * 1000 */
	dpriv->timv = readl(hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
	dpriv->timv = FIELD_GET(AHCI_DWC_HOST_TIMV_MASK, dpriv->timv);
	rate = clk_get_rate(aclk) / 1000UL;
	if (rate == dpriv->timv)
	return;

	dev_info(&dpriv->pdev->dev, "Update CCC/DevSlp timer for Fapp %lu MHz\n",
	rate / 1000UL);
	dpriv->timv = FIELD_PREP(AHCI_DWC_HOST_TIMV_MASK, rate);
	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
	}

	static int ahci_dwc_init_dmacr(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	struct device_node *child;
	void __iomem *port_mmio;
	u32 port, dmacr, ts;

	/*
	* Update the DMA Tx/Rx transaction sizes in accordance with the
	* platform setup. Note values exceeding maximal or minimal limits will
	* be automatically clamped. Also note the register isn't affected by
	* the HBA global reset so we can freely initialize it once until the
	* next system reset.
	*/
	for_each_child_of_node(dpriv->pdev->dev.of_node, child) {
	if (!of_device_is_available(child))
	continue;

	if (of_property_read_u32(child, "reg", &port)) {
	of_node_put(child);
	return -EINVAL;
	}

	port_mmio = __ahci_port_base(hpriv, port);
	dmacr = readl(port_mmio + AHCI_DWC_PORT_DMACR);

	if (!of_property_read_u32(child, "snps,tx-ts-max", &ts)) {
	ts = ilog2(ts);
	dmacr &= ~AHCI_DWC_PORT_TXTS_MASK;
	dmacr \|= FIELD_PREP(AHCI_DWC_PORT_TXTS_MASK, ts);
	}

	if (!of_property_read_u32(child, "snps,rx-ts-max", &ts)) {
	ts = ilog2(ts);
	dmacr &= ~AHCI_DWC_PORT_RXTS_MASK;
	dmacr \|= FIELD_PREP(AHCI_DWC_PORT_RXTS_MASK, ts);
	}

	writel(dmacr, port_mmio + AHCI_DWC_PORT_DMACR);
	dpriv->dmacr[port] = dmacr;
	}

	return 0;
	}

	static int ahci_dwc_init_host(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	int rc;

	rc = ahci_platform_enable_resources(hpriv);
	if (rc)
	return rc;

	if (dpriv->pdata->init) {
	rc = dpriv->pdata->init(hpriv);
	if (rc)
	goto err_disable_resources;
	}

	ahci_dwc_check_cap(hpriv);

	ahci_dwc_init_timer(hpriv);

	rc = ahci_dwc_init_dmacr(hpriv);
	if (rc)
	goto err_clear_platform;

	return 0;

	err_clear_platform:
	if (dpriv->pdata->clear)
	dpriv->pdata->clear(hpriv);

	err_disable_resources:
	ahci_platform_disable_resources(hpriv);

	return rc;
	}

	static int ahci_dwc_reinit_host(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
	unsigned long port_map = hpriv->port_map;
	void __iomem *port_mmio;
	int i, rc;

	rc = ahci_platform_enable_resources(hpriv);
	if (rc)
	return rc;

	if (dpriv->pdata->reinit) {
	rc = dpriv->pdata->reinit(hpriv);
	if (rc)
	goto err_disable_resources;
	}

	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);

	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
	port_mmio = __ahci_port_base(hpriv, i);
	writel(dpriv->dmacr[i], port_mmio + AHCI_DWC_PORT_DMACR);
	}

	return 0;

	err_disable_resources:
	ahci_platform_disable_resources(hpriv);

	return rc;
	}

	static void ahci_dwc_clear_host(struct ahci_host_priv *hpriv)
	{
	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;

	if (dpriv->pdata->clear)
	dpriv->pdata->clear(hpriv);

	ahci_platform_disable_resources(hpriv);
	}

	static void ahci_dwc_stop_host(struct ata_host *host)
	{
	struct ahci_host_priv *hpriv = host->private_data;

	ahci_dwc_clear_host(hpriv);
	}

	static struct ata_port_operations ahci_dwc_port_ops = {
	.inherits = &ahci_platform_ops,
	.host_stop = ahci_dwc_stop_host,
	};

	static const struct ata_port_info ahci_dwc_port_info = {
	.flags = AHCI_FLAG_COMMON,
	.pio_mask = ATA_PIO4,
	.udma_mask = ATA_UDMA6,
	.port_ops = &ahci_dwc_port_ops,
	};

	static const struct scsi_host_template ahci_dwc_scsi_info = {
	AHCI_SHT(DRV_NAME),
	};

	static int ahci_dwc_probe(struct platform_device *pdev)
	{
	struct ahci_host_priv *hpriv;
	int rc;

	hpriv = ahci_dwc_get_resources(pdev);
	if (IS_ERR(hpriv))
	return PTR_ERR(hpriv);

	rc = ahci_dwc_init_host(hpriv);
	if (rc)
	return rc;

	rc = ahci_platform_init_host(pdev, hpriv, &ahci_dwc_port_info,
	&ahci_dwc_scsi_info);
	if (rc)
	goto err_clear_host;

	return 0;

	err_clear_host:
	ahci_dwc_clear_host(hpriv);

	return rc;
	}

	static int ahci_dwc_suspend(struct device *dev)
	{
	struct ata_host *host = dev_get_drvdata(dev);
	struct ahci_host_priv *hpriv = host->private_data;
	int rc;

	rc = ahci_platform_suspend_host(dev);
	if (rc)
	return rc;

	ahci_dwc_clear_host(hpriv);

	return 0;
	}

	static int ahci_dwc_resume(struct device *dev)
	{
	struct ata_host *host = dev_get_drvdata(dev);
	struct ahci_host_priv *hpriv = host->private_data;
	int rc;

	rc = ahci_dwc_reinit_host(hpriv);
	if (rc)
	return rc;

	return ahci_platform_resume_host(dev);
	}

	static DEFINE_SIMPLE_DEV_PM_OPS(ahci_dwc_pm_ops, ahci_dwc_suspend,
	ahci_dwc_resume);

	static struct ahci_dwc_plat_data ahci_dwc_plat = {
	.pflags = AHCI_PLATFORM_GET_RESETS,
	};

	static struct ahci_dwc_plat_data ahci_bt1_plat = {
	.pflags = AHCI_PLATFORM_GET_RESETS \| AHCI_PLATFORM_RST_TRIGGER,
	.init = ahci_bt1_init,
	};

	static const struct of_device_id ahci_dwc_of_match[] = {
	{ .compatible = "snps,dwc-ahci", &ahci_dwc_plat },
	{ .compatible = "snps,spear-ahci", &ahci_dwc_plat },
	{ .compatible = "baikal,bt1-ahci", &ahci_bt1_plat },
	{},
	};
	MODULE_DEVICE_TABLE(of, ahci_dwc_of_match);

	static struct platform_driver ahci_dwc_driver = {
	.probe = ahci_dwc_probe,
	.remove = ata_platform_remove_one,
	.shutdown = ahci_platform_shutdown,
	.driver = {
	.name = DRV_NAME,
	.of_match_table = ahci_dwc_of_match,
	.pm = &ahci_dwc_pm_ops,
	},
	};
	module_platform_driver(ahci_dwc_driver);

	MODULE_DESCRIPTION("DWC AHCI SATA platform driver");
	MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
	MODULE_LICENSE("GPL");