Re: [PATCH v6 08/14] mmc: sdhci-xenon: Add Marvell Xenon SDHC core functionality

[Adrian Hunter]

On 14/02/17 19:01, Gregory CLEMENT wrote:
> From: Hu Ziji <huziji@xxxxxxxxxxx>
> 
> Add Xenon eMMC/SD/SDIO host controller core functionality.
> Add Xenon specific initialization process.
> Add Xenon specific mmc_host_ops APIs.
> Add Xenon specific register definitions.
> 
> Add CONFIG_MMC_SDHCI_XENON support in drivers/mmc/host/Kconfig.
> 
> Marvell Xenon SDHC conforms to SD Physical Layer Specification
> Version 3.01 and is designed according to the guidelines provided
> in the SD Host Controller Standard Specification Version 3.00.
> 
> Signed-off-by: Hu Ziji <huziji@xxxxxxxxxxx>
> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>

A few minor comments below.

> ---
>  drivers/mmc/host/Kconfig       |   9 +-
>  drivers/mmc/host/Makefile      |   3 +-
>  drivers/mmc/host/sdhci-xenon.c | 602 ++++++++++++++++++++++++++++++++++-
>  drivers/mmc/host/sdhci-xenon.h |  70 ++++-
>  4 files changed, 684 insertions(+)
>  create mode 100644 drivers/mmc/host/sdhci-xenon.c
>  create mode 100644 drivers/mmc/host/sdhci-xenon.h
> 
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 2eb97014dc3f..1c1a88bfbdad 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -819,3 +819,12 @@ config MMC_SDHCI_BRCMSTB
>  	  Broadcom STB SoCs.
>  
>  	  If unsure, say Y.
> +
> +config MMC_SDHCI_XENON
> +	tristate "Marvell Xenon eMMC/SD/SDIO SDHCI driver"
> +	depends on MMC_SDHCI_PLTFM
> +	help
> +	  This selects Marvell Xenon eMMC/SD/SDIO SDHCI.
> +	  If you have a machine with integrated Marvell Xenon SDHC IP,
> +	  say Y or M here.
> +	  If unsure, say N.
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index ccc9c4cba154..b0a2ab4b256e 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -82,3 +82,6 @@ obj-$(CONFIG_MMC_SDHCI_BRCMSTB)		+= sdhci-brcmstb.o
>  ifeq ($(CONFIG_CB710_DEBUG),y)
>  	CFLAGS-cb710-mmc	+= -DDEBUG
>  endif
> +
> +obj-$(CONFIG_MMC_SDHCI_XENON)	+= sdhci-xenon-driver.o
> +sdhci-xenon-driver-y		+= sdhci-xenon.o
> diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c
> new file mode 100644
> index 000000000000..e633f803907a
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-xenon.c
> @@ -0,0 +1,602 @@
> +/*
> + * Driver for Marvell Xenon SDHC as a platform device
> + *
> + * Copyright (C) 2016 Marvell, All Rights Reserved.
> + *
> + * Author:	Hu Ziji <huziji@xxxxxxxxxxx>
> + * Date:	2016-8-24
> + *
> + * 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 version 2.
> + *
> + * Inspired by Jisheng Zhang <jszhang@xxxxxxxxxxx>
> + * Special thanks to Video BG4 project team.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +
> +#include "sdhci-pltfm.h"
> +#include "sdhci-xenon.h"
> +
> +static int enable_xenon_internal_clk(struct sdhci_host *host)
> +{
> +	u32 reg;
> +	u8 timeout;
> +
> +	reg = sdhci_readl(host, SDHCI_CLOCK_CONTROL);
> +	reg |= SDHCI_CLOCK_INT_EN;
> +	sdhci_writel(host, reg, SDHCI_CLOCK_CONTROL);
> +	/* Wait max 20 ms */
> +	timeout = 20;
> +	while (!((reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
> +			& SDHCI_CLOCK_INT_STABLE)) {
> +		if (timeout == 0) {
> +			pr_err("%s: Internal clock never stabilised.\n",
> +			       mmc_hostname(host->mmc));
> +			return -ETIMEDOUT;
> +		}
> +		timeout--;
> +		mdelay(1);

If it takes a lot less than 1 ms this can waste time.  See recent patch
"mmc: sdhci: Optimize delay loops"

> +	}
> +
> +	return 0;
> +}
> +
> +/* Set SDCLK-off-while-idle */
> +static void xenon_set_sdclk_off_idle(struct sdhci_host *host,
> +				     unsigned char sdhc_id, bool enable)
> +{
> +	u32 reg;
> +	u32 mask;
> +
> +	reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
> +	/* Get the bit shift basing on the SDHC index */
> +	mask = (0x1 << (XENON_SDCLK_IDLEOFF_ENABLE_SHIFT + sdhc_id));
> +	if (enable)
> +		reg |= mask;
> +	else
> +		reg &= ~mask;
> +
> +	sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
> +}
> +
> +/* Enable/Disable the Auto Clock Gating function */
> +static void xenon_set_acg(struct sdhci_host *host, bool enable)
> +{
> +	u32 reg;
> +
> +	reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
> +	if (enable)
> +		reg &= ~XENON_AUTO_CLKGATE_DISABLE_MASK;
> +	else
> +		reg |= XENON_AUTO_CLKGATE_DISABLE_MASK;
> +	sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
> +}
> +
> +/* Enable this SDHC */
> +static void xenon_enable_sdhc(struct sdhci_host *host,
> +			      unsigned char sdhc_id)
> +{
> +	u32 reg;
> +
> +	reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
> +	reg |= (BIT(sdhc_id) << XENON_SLOT_ENABLE_SHIFT);
> +	sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
> +
> +	/*
> +	 * Manually set the flag which all the card types require,
> +	 * including SD, eMMC, SDIO
> +	 */
> +	host->mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
> +}
> +
> +/* Disable this SDHC */
> +static void xenon_disable_sdhc(struct sdhci_host *host,
> +			       unsigned char sdhc_id)
> +{
> +	u32 reg;
> +
> +	reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
> +	reg &= ~(BIT(sdhc_id) << XENON_SLOT_ENABLE_SHIFT);
> +	sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
> +}
> +
> +/* Enable Parallel Transfer Mode */
> +static void xenon_enable_sdhc_parallel_tran(struct sdhci_host *host,
> +					    unsigned char sdhc_id)
> +{
> +	u32 reg;
> +
> +	reg = sdhci_readl(host, XENON_SYS_EXT_OP_CTRL);
> +	reg |= BIT(sdhc_id);
> +	sdhci_writel(host, reg, XENON_SYS_EXT_OP_CTRL);
> +}
> +
> +/* Mask command conflict error */
> +static void xenon_mask_cmd_conflict_err(struct sdhci_host *host)
> +{
> +	u32  reg;
> +
> +	reg = sdhci_readl(host, XENON_SYS_EXT_OP_CTRL);
> +	reg |= XENON_MASK_CMD_CONFLICT_ERR;
> +	sdhci_writel(host, reg, XENON_SYS_EXT_OP_CTRL);
> +}
> +
> +static void xenon_sdhc_retune_setup(struct sdhci_host *host)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	u32 reg;
> +
> +	/* Disable the Re-Tuning Request functionality */
> +	reg = sdhci_readl(host, XENON_SLOT_RETUNING_REQ_CTRL);
> +	reg &= ~XENON_RETUNING_COMPATIBLE;
> +	sdhci_writel(host, reg, XENON_SLOT_RETUNING_REQ_CTRL);
> +
> +	/* Disable the Re-tuning Interrupt */
> +	reg = sdhci_readl(host, SDHCI_SIGNAL_ENABLE);
> +	reg &= ~SDHCI_INT_RETUNE;
> +	sdhci_writel(host, reg, SDHCI_SIGNAL_ENABLE);
> +	reg = sdhci_readl(host, SDHCI_INT_ENABLE);
> +	reg &= ~SDHCI_INT_RETUNE;
> +	sdhci_writel(host, reg, SDHCI_INT_ENABLE);
> +
> +	/* Force to use Tuning Mode 1 */
> +	host->tuning_mode = SDHCI_TUNING_MODE_1;
> +	/* Set re-tuning period */
> +	host->tuning_count = 1 << (priv->tuning_count - 1);
> +}
> +
> +/*
> + * Operations inside struct sdhci_ops
> + */
> +/* Recover the Register Setting cleared during SOFTWARE_RESET_ALL */
> +static void sdhci_xenon_reset_exit(struct sdhci_host *host,
> +				   unsigned char sdhc_id, u8 mask)
> +{
> +	/* Only SOFTWARE RESET ALL will clear the register setting */
> +	if (!(mask & SDHCI_RESET_ALL))
> +		return;
> +
> +	/* Disable tuning request and auto-retuning again */
> +	xenon_sdhc_retune_setup(host);
> +
> +	xenon_set_acg(host, true);
> +
> +	xenon_set_sdclk_off_idle(host, sdhc_id, false);
> +
> +	xenon_mask_cmd_conflict_err(host);
> +}
> +
> +static void sdhci_xenon_reset(struct sdhci_host *host, u8 mask)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +
> +	sdhci_reset(host, mask);
> +	sdhci_xenon_reset_exit(host, priv->sdhc_id, mask);
> +}
> +
> +/*
> + * Xenon defines different values for HS200 and HS400
> + * in Host_Control_2
> + */
> +static void xenon_set_uhs_signaling(struct sdhci_host *host,
> +				    unsigned int timing)
> +{
> +	u16 ctrl_2;
> +
> +	ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> +	/* Select Bus Speed Mode for host */
> +	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
> +	if (timing == MMC_TIMING_MMC_HS200)
> +		ctrl_2 |= XENON_CTRL_HS200;
> +	else if (timing == MMC_TIMING_UHS_SDR104)
> +		ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
> +	else if (timing == MMC_TIMING_UHS_SDR12)
> +		ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
> +	else if (timing == MMC_TIMING_UHS_SDR25)
> +		ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
> +	else if (timing == MMC_TIMING_UHS_SDR50)
> +		ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
> +	else if ((timing == MMC_TIMING_UHS_DDR50) ||
> +		 (timing == MMC_TIMING_MMC_DDR52))
> +		ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
> +	else if (timing == MMC_TIMING_MMC_HS400)
> +		ctrl_2 |= XENON_CTRL_HS400;
> +	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
> +}
> +
> +static const struct sdhci_ops sdhci_xenon_ops = {
> +	.set_clock		= sdhci_set_clock,
> +	.set_bus_width		= sdhci_set_bus_width,
> +	.reset			= sdhci_xenon_reset,
> +	.set_uhs_signaling	= xenon_set_uhs_signaling,
> +	.get_max_clock		= sdhci_pltfm_clk_get_max_clock,
> +};
> +
> +static const struct sdhci_pltfm_data sdhci_xenon_pdata = {
> +	.ops = &sdhci_xenon_ops,
> +	.quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
> +		  SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER |
> +		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
> +};
> +
> +/*
> + * Xenon Specific Operations in mmc_host_ops
> + */
> +static void xenon_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	unsigned long flags;
> +	u32 reg;
> +
> +	/*
> +	 * HS400/HS200/eMMC HS doesn't have Preset Value register.
> +	 * However, sdhci_set_ios will read HS400/HS200 Preset register.
> +	 * Disable Preset Value register for HS400/HS200.
> +	 * eMMC HS with preset_enabled set will trigger a bug in
> +	 * get_preset_value().
> +	 */
> +	spin_lock_irqsave(&host->lock, flags);

We are no longer using the spin lock in set_ios.  See recent patch "mmc:
sdhci: Do not use spin lock in set_ios paths"

> +	if ((ios->timing == MMC_TIMING_MMC_HS400) ||
> +	    (ios->timing == MMC_TIMING_MMC_HS200) ||
> +	    (ios->timing == MMC_TIMING_MMC_HS)) {
> +		host->preset_enabled = false;
> +		host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
> +		host->flags &= ~SDHCI_PV_ENABLED;
> +
> +		reg = sdhci_readw(host, SDHCI_HOST_CONTROL2);
> +		reg &= ~SDHCI_CTRL_PRESET_VAL_ENABLE;
> +		sdhci_writew(host, reg, SDHCI_HOST_CONTROL2);
> +	} else {
> +		host->quirks2 &= ~SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
> +	}
> +	spin_unlock_irqrestore(&host->lock, flags);
> +
> +	sdhci_set_ios(mmc, ios);
> +
> +	if (host->clock > XENON_DEFAULT_SDCLK_FREQ) {
> +		spin_lock_irqsave(&host->lock, flags);
> +		xenon_set_sdclk_off_idle(host, priv->sdhc_id, true);
> +		spin_unlock_irqrestore(&host->lock, flags);
> +	}
> +}
> +
> +static int xenon_emmc_signal_voltage_switch(struct mmc_host *mmc,
> +					    struct mmc_ios *ios)
> +{
> +	unsigned char voltage = ios->signal_voltage;
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	unsigned char voltage_code;
> +	u32 ctrl;
> +
> +	if ((voltage == MMC_SIGNAL_VOLTAGE_330) ||
> +	    (voltage == MMC_SIGNAL_VOLTAGE_180)) {
> +		if (voltage == MMC_SIGNAL_VOLTAGE_330)
> +			voltage_code = XENON_EMMC_VCCQ_3_3V;
> +		else if (voltage == MMC_SIGNAL_VOLTAGE_180)
> +			voltage_code = XENON_EMMC_VCCQ_1_8V;
> +
> +		/*
> +		 * This host is for eMMC, XENON self-defined
> +		 * eMMC control register should be accessed
> +		 * instead of Host Control 2
> +		 */
> +		ctrl = sdhci_readl(host, XENON_SLOT_EMMC_CTRL);
> +		ctrl &= ~XENON_EMMC_VCCQ_MASK;
> +		ctrl |= voltage_code;
> +		sdhci_writel(host, ctrl, XENON_SLOT_EMMC_CTRL);
> +
> +		/* There is no standard to determine this waiting period */
> +		usleep_range(1000, 2000);
> +
> +		/* Check whether io voltage switch is done */
> +		ctrl = sdhci_readl(host, XENON_SLOT_EMMC_CTRL);
> +		ctrl &= XENON_EMMC_VCCQ_MASK;
> +		/*
> +		 * This bit is set only when regulator feeds back
> +		 * the voltage switch results to Xenon SDHC.
> +		 * However, in actaul implementation, regulator might not

actaul -> actual

> +		 * provide this feedback.
> +		 * Thus we shall not rely on this bit to determine
> +		 * if switch failed.
> +		 * If the bit is not set, just throw a message.
> +		 * Besides, error code should not be returned.
> +		 */
> +		if (ctrl != voltage_code)
> +			dev_info(mmc_dev(mmc), "fail to detect eMMC signal voltage stable\n");
> +		return 0;
> +	}
> +
> +	dev_err(mmc_dev(mmc), "Unsupported signal voltage: %d\n", voltage);
> +	return -EINVAL;
> +}
> +
> +static int xenon_start_signal_voltage_switch(struct mmc_host *mmc,
> +					     struct mmc_ios *ios)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +
> +	/*
> +	 * Before SD/SDIO set signal voltage, SD bus clock should be
> +	 * disabled. However, sdhci_set_clock will also disable the Internal
> +	 * clock in mmc_set_signal_voltage().
> +	 * If Internal clock is disabled, the 3.3V/1.8V bit can not be updated.
> +	 * Thus here manually enable internal clock.
> +	 *
> +	 * After switch completes, it is unnecessary to disable internal clock,
> +	 * since keeping internal clock active obeys SD spec.
> +	 */
> +	enable_xenon_internal_clk(host);
> +
> +	if (priv->init_card_type == MMC_TYPE_MMC)
> +		return xenon_emmc_signal_voltage_switch(mmc, ios);
> +
> +	return sdhci_start_signal_voltage_switch(mmc, ios);
> +}
> +
> +/*
> + * Update card type.
> + * priv->init_card_type will be used in PHY timing adjustment.
> + */
> +static void xenon_init_card(struct mmc_host *mmc, struct mmc_card *card)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +
> +	/* Update card type*/
> +	priv->init_card_type = card->type;
> +}
> +
> +static int xenon_execute_tuning(struct mmc_host *mmc, u32 opcode)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +
> +	if (host->timing == MMC_TIMING_UHS_DDR50)
> +		return 0;
> +
> +	/*
> +	 * Currently force Xenon driver back to support mode 1 only,
> +	 * even though Xenon might claim to support mode 2 or mode 3.
> +	 * It requires more time to test mode 2/mode 3 on more platforms.
> +	 */
> +	if (host->tuning_mode != SDHCI_TUNING_MODE_1)
> +		xenon_sdhc_retune_setup(host);
> +
> +	return sdhci_execute_tuning(mmc, opcode);
> +}
> +
> +static void xenon_enable_sdio_irq(struct mmc_host *mmc, int enable)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	u32 reg;
> +	u8 sdhc_id = priv->sdhc_id;
> +
> +	sdhci_enable_sdio_irq(mmc, enable);
> +
> +	if (enable) {
> +		/*
> +		 * Set SDIO Card Inserted indication
> +		 * to enable detecting SDIO async irq.
> +		 */
> +		reg = sdhci_readl(host, XENON_SYS_CFG_INFO);
> +		reg |= (1 << (sdhc_id + XENON_SLOT_TYPE_SDIO_SHIFT));
> +		sdhci_writel(host, reg, XENON_SYS_CFG_INFO);
> +	} else {
> +		/* Clear SDIO Card Inserted indication */
> +		reg = sdhci_readl(host, XENON_SYS_CFG_INFO);
> +		reg &= ~(1 << (sdhc_id + XENON_SLOT_TYPE_SDIO_SHIFT));
> +		sdhci_writel(host, reg, XENON_SYS_CFG_INFO);
> +	}
> +}
> +
> +static void xenon_replace_mmc_host_ops(struct sdhci_host *host)
> +{
> +	host->mmc_host_ops.set_ios = xenon_set_ios;
> +	host->mmc_host_ops.start_signal_voltage_switch =
> +			xenon_start_signal_voltage_switch;
> +	host->mmc_host_ops.init_card = xenon_init_card;
> +	host->mmc_host_ops.execute_tuning = xenon_execute_tuning;
> +	host->mmc_host_ops.enable_sdio_irq = xenon_enable_sdio_irq;
> +}
> +
> +/*
> + * Parse Xenon specific DT properties:
> + * init_card_type: check whether this SDHC is for eMMC
> + * sdhc-id: the index of current SDHC.
> + *	    Refer to XENON_SYS_CFG_INFO register
> + * tun-count: the interval between re-tuning
> + */
> +static int xenon_probe_dt(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct sdhci_host *host = platform_get_drvdata(pdev);
> +	struct mmc_host *mmc = host->mmc;
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	u32 sdhc_id, nr_sdhc;
> +	u32 tuning_count;
> +
> +	/* Disable HS200 on Armada AP806 */
> +	if (of_device_is_compatible(np, "marvell,armada-ap806-sdhci"))
> +		host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;
> +
> +	priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
> +	/* Check if mmc-card sub-node exists */
> +	if (mmc_of_parse_mmc_card(mmc)) {
> +		priv->init_card_type = MMC_TYPE_MMC;
> +		/*
> +		 * Force to clear BUS_TEST to
> +		 * skip bus_test_pre and bus_test_post
> +		 */
> +		mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
> +	}
> +
> +	priv->sdhc_id = 0x0;
> +	if (!of_property_read_u32(np, "marvell,xenon-sdhc-id", &sdhc_id)) {
> +		nr_sdhc = sdhci_readl(host, XENON_SYS_CFG_INFO);
> +		nr_sdhc &= XENON_NR_SUPPORTED_SLOT_MASK;
> +		if (unlikely(sdhc_id > nr_sdhc)) {
> +			dev_err(mmc_dev(mmc), "SDHC Index %d exceeds Number of SDHCs %d\n",
> +				sdhc_id, nr_sdhc);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	tuning_count = XENON_DEF_TUNING_COUNT;
> +	if (!of_property_read_u32(np, "marvell,xenon-tun-count",
> +				  &tuning_count)) {
> +		if (unlikely(tuning_count >= XENON_TMR_RETUN_NO_PRESENT)) {
> +			dev_err(mmc_dev(mmc), "Wrong Re-tuning Count. Set default value %d\n",
> +				XENON_DEF_TUNING_COUNT);
> +			tuning_count = XENON_DEF_TUNING_COUNT;
> +		}
> +	}
> +	priv->tuning_count = tuning_count;
> +
> +	return 0;
> +}
> +
> +static int xenon_sdhc_probe(struct sdhci_host *host)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	u8 sdhc_id = priv->sdhc_id;
> +
> +	/* Enable SDHC */
> +	xenon_enable_sdhc(host, sdhc_id);
> +
> +	/* Enable ACG */
> +	xenon_set_acg(host, true);
> +
> +	/* Enable Parallel Transfer Mode */
> +	xenon_enable_sdhc_parallel_tran(host, sdhc_id);
> +
> +	xenon_mask_cmd_conflict_err(host);
> +
> +	return 0;
> +}
> +
> +static void xenon_sdhc_remove(struct sdhci_host *host)
> +{
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
> +	u8 sdhc_id = priv->sdhc_id;
> +
> +	/* disable SDHC */
> +	xenon_disable_sdhc(host, sdhc_id);
> +}
> +
> +static int sdhci_xenon_probe(struct platform_device *pdev)
> +{
> +	struct sdhci_pltfm_host *pltfm_host;
> +	struct sdhci_host *host;
> +	struct sdhci_xenon_priv *priv;
> +	int err;
> +
> +	host = sdhci_pltfm_init(pdev, &sdhci_xenon_pdata,
> +				sizeof(struct sdhci_xenon_priv));
> +	if (IS_ERR(host))
> +		return PTR_ERR(host);
> +
> +	pltfm_host = sdhci_priv(host);
> +	priv = sdhci_pltfm_priv(pltfm_host);
> +
> +	xenon_set_acg(host, false);
> +
> +	/*
> +	 * Link Xenon specific mmc_host_ops function,
> +	 * to replace standard ones in sdhci_ops.
> +	 */
> +	xenon_replace_mmc_host_ops(host);
> +
> +	pltfm_host->clk = devm_clk_get(&pdev->dev, "core");
> +	if (IS_ERR(pltfm_host->clk)) {
> +		err = PTR_ERR(pltfm_host->clk);
> +		dev_err(&pdev->dev, "Failed to setup input clk: %d\n", err);
> +		goto free_pltfm;
> +	}
> +	err = clk_prepare_enable(pltfm_host->clk);
> +	if (err)
> +		goto free_pltfm;
> +
> +	err = mmc_of_parse(host->mmc);
> +	if (err)
> +		goto err_clk;
> +
> +	sdhci_get_of_property(pdev);
> +
> +	/* Xenon specific dt parse */
> +	err = xenon_probe_dt(pdev);
> +	if (err)
> +		goto err_clk;
> +
> +	err = xenon_sdhc_probe(host);
> +	if (err)
> +		goto err_clk;
> +
> +	err = sdhci_add_host(host);
> +	if (err)
> +		goto remove_sdhc;
> +
> +	return 0;
> +
> +remove_sdhc:
> +	xenon_sdhc_remove(host);
> +err_clk:
> +	clk_disable_unprepare(pltfm_host->clk);
> +free_pltfm:
> +	sdhci_pltfm_free(pdev);
> +	return err;
> +}
> +
> +static int sdhci_xenon_remove(struct platform_device *pdev)
> +{
> +	struct sdhci_host *host = platform_get_drvdata(pdev);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +
> +	xenon_sdhc_remove(host);
> +
> +	sdhci_remove_host(host, 0);
> +
> +	clk_disable_unprepare(pltfm_host->clk);
> +
> +	sdhci_pltfm_free(pdev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id sdhci_xenon_dt_ids[] = {
> +	{ .compatible = "marvell,armada-ap806-sdhci",},
> +	{ .compatible = "marvell,armada-cp110-sdhci",},
> +	{ .compatible = "marvell,armada-3700-sdhci",},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, sdhci_xenon_dt_ids);
> +
> +static struct platform_driver sdhci_xenon_driver = {
> +	.driver	= {
> +		.name	= "xenon-sdhci",
> +		.of_match_table = sdhci_xenon_dt_ids,
> +		.pm = &sdhci_pltfm_pmops,
> +	},
> +	.probe	= sdhci_xenon_probe,
> +	.remove	= sdhci_xenon_remove,
> +};
> +
> +module_platform_driver(sdhci_xenon_driver);
> +
> +MODULE_DESCRIPTION("SDHCI platform driver for Marvell Xenon SDHC");
> +MODULE_AUTHOR("Hu Ziji <huziji@xxxxxxxxxxx>");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/mmc/host/sdhci-xenon.h b/drivers/mmc/host/sdhci-xenon.h
> new file mode 100644
> index 000000000000..69de711db9eb
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-xenon.h
> @@ -0,0 +1,70 @@
> +/*
> + * Copyright (C) 2016 Marvell, All Rights Reserved.
> + *
> + * Author:	Hu Ziji <huziji@xxxxxxxxxxx>
> + * Date:	2016-8-24
> + *
> + * 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 version 2.
> + */
> +#ifndef SDHCI_XENON_H_
> +#define SDHCI_XENON_H_
> +
> +/* Register Offset of Xenon SDHC self-defined register */
> +#define XENON_SYS_CFG_INFO			0x0104
> +#define XENON_SLOT_TYPE_SDIO_SHIFT		24
> +#define XENON_NR_SUPPORTED_SLOT_MASK		0x7
> +
> +#define XENON_SYS_OP_CTRL			0x0108
> +#define XENON_AUTO_CLKGATE_DISABLE_MASK		BIT(20)
> +#define XENON_SDCLK_IDLEOFF_ENABLE_SHIFT	8
> +#define XENON_SLOT_ENABLE_SHIFT			0
> +
> +#define XENON_SYS_EXT_OP_CTRL			0x010C
> +#define XENON_MASK_CMD_CONFLICT_ERR		BIT(8)
> +
> +#define XENON_SLOT_EMMC_CTRL			0x0130
> +#define XENON_EMMC_VCCQ_MASK			0x3
> +#define XENON_EMMC_VCCQ_1_8V			0x1
> +#define XENON_EMMC_VCCQ_3_3V			0x3
> +
> +#define XENON_SLOT_RETUNING_REQ_CTRL		0x0144
> +/* retuning compatible */
> +#define XENON_RETUNING_COMPATIBLE		0x1
> +
> +/* Tuning Parameter */
> +#define XENON_TMR_RETUN_NO_PRESENT		0xF
> +#define XENON_DEF_TUNING_COUNT			0x9
> +
> +#define XENON_DEFAULT_SDCLK_FREQ		400000
> +
> +/* Xenon specific Mode Select value */
> +#define XENON_CTRL_HS200			0x5
> +#define XENON_CTRL_HS400			0x6
> +
> +/* Indicate Card Type is not clear yet */
> +#define XENON_CARD_TYPE_UNKNOWN			0xF
> +
> +struct sdhci_xenon_priv {
> +	unsigned char	tuning_count;
> +	/* idx of SDHC */
> +	u8		sdhc_id;
> +
> +	/*
> +	 * eMMC/SD/SDIO require different PHY settings or
> +	 * voltage control. It's necessary for Xenon driver to
> +	 * recognize card type during, or even before initialization.
> +	 * However, mmc_host->card is not available yet at that time.
> +	 * This field records the card type during init.
> +	 * For eMMC, it is updated in dt parse. For SD/SDIO, it is
> +	 * updated in xenon_init_card().
> +	 *
> +	 * It is only valid during initialization after it is updated.
> +	 * Do not access this variable in normal transfers after
> +	 * initialization completes.
> +	 */
> +	unsigned int	init_card_type;
> +};
> +
> +#endif
>