diff mbox

[v5,06/12] mmc: sdhci-xenon: Add Marvell Xenon SDHC core functionality

Message ID 3546f143091c121face8ecbcbf7f6a4c41d2cec7.1484154449.git-series.gregory.clement@free-electrons.com (mailing list archive)
State New, archived
Headers show

Commit Message

Gregory CLEMENT Jan. 11, 2017, 5:19 p.m. UTC
From: Hu Ziji <huziji@marvell.com>

Add Xenon eMMC/SD/SDIO host controller core functionality.
Add Xenon specific intialization 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@marvell.com>
Tested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/mmc/host/Kconfig       |   9 +-
 drivers/mmc/host/Makefile      |   3 +-
 drivers/mmc/host/sdhci-xenon.c | 631 ++++++++++++++++++++++++++++++++++-
 drivers/mmc/host/sdhci-xenon.h |  70 ++++-
 4 files changed, 713 insertions(+)
 create mode 100644 drivers/mmc/host/sdhci-xenon.c
 create mode 100644 drivers/mmc/host/sdhci-xenon.h

Comments

Ulf Hansson Jan. 26, 2017, 10:50 a.m. UTC | #1
On 11 January 2017 at 18:19, Gregory CLEMENT
<gregory.clement@free-electrons.com> wrote:
> From: Hu Ziji <huziji@marvell.com>
>
> Add Xenon eMMC/SD/SDIO host controller core functionality.
> Add Xenon specific intialization 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@marvell.com>
> Tested-by: Russell King <rmk+kernel@armlinux.org.uk>
> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> ---
>  drivers/mmc/host/Kconfig       |   9 +-
>  drivers/mmc/host/Makefile      |   3 +-
>  drivers/mmc/host/sdhci-xenon.c | 631 ++++++++++++++++++++++++++++++++++-
>  drivers/mmc/host/sdhci-xenon.h |  70 ++++-
>  4 files changed, 713 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..8d2d08de14a0 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 && MMC_SDHCI_PLTFM

Depending on MMC_SDHCI_PLTFM is enough.

[...]

> +
> +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)

So, you need a specific voltage switch for eMMC.

For that, I don't think you need to implement ->init_card(), as to set
priv->init_card_type and then check it here.

Instead you should be able to find out whether the card is an eMMC,
only by the parsing of the child node for the "mmc-card" compatible.
More about this below.

> +               return xenon_emmc_signal_voltage_switch(mmc, ios);
> +
> +       return sdhci_start_signal_voltage_switch(mmc, ios);
> +}
> +
> +/*

[...]

> + */
> +static int xenon_child_node_of_parse(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);
> +       struct device_node *child;
> +       int nr_child;
> +
> +       priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
> +
> +       nr_child = of_get_child_count(np);
> +       if (!nr_child)
> +               return 0;
> +
> +       for_each_child_of_node(np, child) {
> +               if (of_device_is_compatible(child, "mmc-card")) {

To avoid code from being duplicated, I would rather see the DT parsing
of the child nodes for "mmc-card", to be done by the mmc core.

As a matter of fact it is already being done, but perhaps we need to
change that a bit as to fit your case.

I suggest you have a look and see how to update this in the core,
instead of doing it here in the host driver.

> +                       priv->init_card_type = MMC_TYPE_MMC;
> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
> +
> +                       /*
> +                        * Force to clear BUS_TEST to
> +                        * skip bus_test_pre and bus_test_post
> +                        */
> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |

This cap is a bit strange. It was added several years ago by Adrian
Hunter, but I am wondering about the reason to why it's needed.

Should it be removed and instead enabled per default? If not, should
we invent a new specific DT binding for it?

I need Adrian's help here to understand the options.

> +                                     MMC_CAP2_PACKED_CMD |

The MMC_CAP2_PACKED_CMD cap has be removed.

> +                                     MMC_CAP2_NO_SD |
> +                                     MMC_CAP2_NO_SDIO;

I think we need to update the DT documentation for mmc-card.
Typically, we should explicitly state what kind of other existing mmc
DT properties that will be automatically selected, when the mmc-card
is specified.

Can you please look into updating this DT doc as well.

[...]

> +       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;
> +               }
> +       }

I suggest you move the parsing of the xenon specific bindings into a
separate function.

> +       priv->tuning_count = tuning_count;
> +
> +       return err;
> +}
> +

[...]

Kind regards
Uffe
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Adrian Hunter Jan. 26, 2017, 12:39 p.m. UTC | #2
On 26/01/17 12:50, Ulf Hansson wrote:
> On 11 January 2017 at 18:19, Gregory CLEMENT
> <gregory.clement@free-electrons.com> wrote:
>> +                       priv->init_card_type = MMC_TYPE_MMC;
>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>> +
>> +                       /*
>> +                        * Force to clear BUS_TEST to
>> +                        * skip bus_test_pre and bus_test_post
>> +                        */
>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
> 
> This cap is a bit strange. It was added several years ago by Adrian
> Hunter, but I am wondering about the reason to why it's needed.
> 

MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.

I think it was added to enable people to choose whether they wanted a large
or small erase granularity.  That probably doesn't matter if the card
supports TRIM.

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Ulf Hansson Jan. 27, 2017, 3:12 p.m. UTC | #3
On 26 January 2017 at 13:39, Adrian Hunter <adrian.hunter@intel.com> wrote:
> On 26/01/17 12:50, Ulf Hansson wrote:
>> On 11 January 2017 at 18:19, Gregory CLEMENT
>> <gregory.clement@free-electrons.com> wrote:
>>> +                       priv->init_card_type = MMC_TYPE_MMC;
>>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>>> +
>>> +                       /*
>>> +                        * Force to clear BUS_TEST to
>>> +                        * skip bus_test_pre and bus_test_post
>>> +                        */
>>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>>
>> This cap is a bit strange. It was added several years ago by Adrian
>> Hunter, but I am wondering about the reason to why it's needed.
>>
>
> MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.
>
> I think it was added to enable people to choose whether they wanted a large
> or small erase granularity.  That probably doesn't matter if the card
> supports TRIM.
>

Huh, the erase/trim/discard code in the mmc core is really hairy. :-)

In mmc_calc_max_discard() the following code/comment exists:

/*
 * Without erase_group_def set, MMC erase timeout depends on clock
 * frequence which can change.  In that case, the best choice is
 * just the preferred erase size.
 */
if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
     return card->pref_erase;


This makes me wonder.

So, when we haven't enabled the high capacity erase groups in the
EXT_CSD register (ext_csd.erase_group_def), we will use the pref_erase
size.

In the other case, as when having MMC_CAP2_HC_ERASE_SZ set (which will
set ext_csd.erase_group_def),  we will instead  do some calculations
to find out the max discards.

Are you saying that these calculations doesn't matter much - or are
you saying that we always want to do them?

Kind regards
Uffe
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Hu Ziji Jan. 27, 2017, 4:39 p.m. UTC | #4
Hi Ulf,

On 2017/1/26 18:50, Ulf Hansson wrote:
> On 11 January 2017 at 18:19, Gregory CLEMENT
> <gregory.clement@free-electrons.com> wrote:
>> From: Hu Ziji <huziji@marvell.com>
>>
>> Add Xenon eMMC/SD/SDIO host controller core functionality.
>> Add Xenon specific intialization 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@marvell.com>
>> Tested-by: Russell King <rmk+kernel@armlinux.org.uk>
>> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
>> ---
>>  drivers/mmc/host/Kconfig       |   9 +-
>>  drivers/mmc/host/Makefile      |   3 +-
>>  drivers/mmc/host/sdhci-xenon.c | 631 ++++++++++++++++++++++++++++++++++-
>>  drivers/mmc/host/sdhci-xenon.h |  70 ++++-
>>  4 files changed, 713 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..8d2d08de14a0 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 && MMC_SDHCI_PLTFM
> 
> Depending on MMC_SDHCI_PLTFM is enough.
> 

    Thanks a lot for your review and detailed suggestions.
    They are really helpful.

    I will simplify the dependence to MMC_SDHCI_PLTFM only.

> [...]
> 
>> +
>> +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)
> 
> So, you need a specific voltage switch for eMMC.
> 
> For that, I don't think you need to implement ->init_card(), as to set
> priv->init_card_type and then check it here.
> 
> Instead you should be able to find out whether the card is an eMMC,
> only by the parsing of the child node for the "mmc-card" compatible.
> More about this below.
> 

    I would like to discuss about ->init_card() implementation in
    my reply to our next patch ([PATCH v5 07/12] mmc: sdhci-xenon:
    Add support to PHYs of Marvell Xenon SDHC).

>> +               return xenon_emmc_signal_voltage_switch(mmc, ios);
>> +
>> +       return sdhci_start_signal_voltage_switch(mmc, ios);
>> +}
>> +
>> +/*
> 
> [...]
> 
>> + */
>> +static int xenon_child_node_of_parse(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);
>> +       struct device_node *child;
>> +       int nr_child;
>> +
>> +       priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
>> +
>> +       nr_child = of_get_child_count(np);
>> +       if (!nr_child)
>> +               return 0;
>> +
>> +       for_each_child_of_node(np, child) {
>> +               if (of_device_is_compatible(child, "mmc-card")) {
> 
> To avoid code from being duplicated, I would rather see the DT parsing
> of the child nodes for "mmc-card", to be done by the mmc core.
> 
> As a matter of fact it is already being done, but perhaps we need to
> change that a bit as to fit your case.
> 
> I suggest you have a look and see how to update this in the core,
> instead of doing it here in the host driver.
> 

    I understand your concern.

    It seems that so far "mmc-card" is only used in our Xenon driver.
    Besides, we set Xenon specific parameters and attributions when
    parsing "mmc-card" property.

    May I keep current implementation?
    In my very own opinion, moving it into core layer should be another
    independent patch.
    And it will also cost some more time. To be honest, it is difficult
    for me to bring up a generic core layer implementation to parse
    "mmc-card", since I'm not clear about other vendor's requirement.

>> +                       priv->init_card_type = MMC_TYPE_MMC;
>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>> +
>> +                       /*
>> +                        * Force to clear BUS_TEST to
>> +                        * skip bus_test_pre and bus_test_post
>> +                        */
>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
> 
> This cap is a bit strange. It was added several years ago by Adrian
> Hunter, but I am wondering about the reason to why it's needed.
> 
> Should it be removed and instead enabled per default? If not, should
> we invent a new specific DT binding for it?
> 
> I need Adrian's help here to understand the options.
> 
>> +                                     MMC_CAP2_PACKED_CMD |
> 
> The MMC_CAP2_PACKED_CMD cap has be removed.

    Will remove it in next version.

> 
>> +                                     MMC_CAP2_NO_SD |
>> +                                     MMC_CAP2_NO_SDIO;
> 
> I think we need to update the DT documentation for mmc-card.
> Typically, we should explicitly state what kind of other existing mmc
> DT properties that will be automatically selected, when the mmc-card
> is specified.
> 
> Can you please look into updating this DT doc as well.
> 

  Similar to above, may I keep it now and bring up another patch later
  to update mmc-card DT and parsing?

> [...]
> 
>> +       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;
>> +               }
>> +       }
> 
> I suggest you move the parsing of the xenon specific bindings into a
> separate function.
> 

    I totally agree with you.

>> +       priv->tuning_count = tuning_count;
>> +
>> +       return err;
>> +}
>> +
> 
> [...]
> 
> Kind regards
> Uffe
> 
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Adrian Hunter Jan. 28, 2017, 8:16 a.m. UTC | #5
On 27/01/2017 5:12 p.m., Ulf Hansson wrote:
> On 26 January 2017 at 13:39, Adrian Hunter <adrian.hunter@intel.com> wrote:
>> On 26/01/17 12:50, Ulf Hansson wrote:
>>> On 11 January 2017 at 18:19, Gregory CLEMENT
>>> <gregory.clement@free-electrons.com> wrote:
>>>> +                       priv->init_card_type = MMC_TYPE_MMC;
>>>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>>>> +
>>>> +                       /*
>>>> +                        * Force to clear BUS_TEST to
>>>> +                        * skip bus_test_pre and bus_test_post
>>>> +                        */
>>>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>>>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>>>
>>> This cap is a bit strange. It was added several years ago by Adrian
>>> Hunter, but I am wondering about the reason to why it's needed.
>>>
>>
>> MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.
>>
>> I think it was added to enable people to choose whether they wanted a large
>> or small erase granularity.  That probably doesn't matter if the card
>> supports TRIM.
>>
>
> Huh, the erase/trim/discard code in the mmc core is really hairy. :-)
>
> In mmc_calc_max_discard() the following code/comment exists:
>
> /*
>  * Without erase_group_def set, MMC erase timeout depends on clock
>  * frequence which can change.  In that case, the best choice is
>  * just the preferred erase size.
>  */
> if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
>      return card->pref_erase;
>
>
> This makes me wonder.
>
> So, when we haven't enabled the high capacity erase groups in the
> EXT_CSD register (ext_csd.erase_group_def), we will use the pref_erase
> size.
>
> In the other case, as when having MMC_CAP2_HC_ERASE_SZ set (which will
> set ext_csd.erase_group_def),  we will instead  do some calculations
> to find out the max discards.
>
> Are you saying that these calculations doesn't matter much - or are
> you saying that we always want to do them?

No, I was saying that if you have TRIM then TRIM is preferred to ERASE so 
the erase group size does not come into play when discarding, since ERASE 
granularity is erase groups whereas TRIM granularity is sectors.

However ERASE_GROUP_DEF also affects the size of write protect groups.
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Ulf Hansson Jan. 30, 2017, 8:41 a.m. UTC | #6
[...]

>>> + */
>>> +static int xenon_child_node_of_parse(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);
>>> +       struct device_node *child;
>>> +       int nr_child;
>>> +
>>> +       priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
>>> +
>>> +       nr_child = of_get_child_count(np);
>>> +       if (!nr_child)
>>> +               return 0;
>>> +
>>> +       for_each_child_of_node(np, child) {
>>> +               if (of_device_is_compatible(child, "mmc-card")) {
>>
>> To avoid code from being duplicated, I would rather see the DT parsing
>> of the child nodes for "mmc-card", to be done by the mmc core.
>>
>> As a matter of fact it is already being done, but perhaps we need to
>> change that a bit as to fit your case.
>>
>> I suggest you have a look and see how to update this in the core,
>> instead of doing it here in the host driver.
>>
>
>     I understand your concern.
>
>     It seems that so far "mmc-card" is only used in our Xenon driver.

git grep "mmc-card" tells you more about where it's being parsed by
the mmc core.

>     Besides, we set Xenon specific parameters and attributions when
>     parsing "mmc-card" property.

I don't see any Xenon specific properties.

Instead I think it would make sense to update the generic
interpretation of the binding for mmc-card, as you have done here.

>
>     May I keep current implementation?

Rather not. Let's try to make the parsing of the child node for
mmc-card generic.

>     In my very own opinion, moving it into core layer should be another
>     independent patch.

Absolutely an independent patch. Whether it can be done as a part of
mmc_of_parse() or whether we need yet another new mmc_of* API, we can
discuss.

My point is that, I don't this to be specific for Xenon (unless there
are specific reason, which I don't see here).

>     And it will also cost some more time. To be honest, it is difficult
>     for me to bring up a generic core layer implementation to parse
>     "mmc-card", since I'm not clear about other vendor's requirement.

Well, then you need to learn more about how the mmc core works. In
this case, it shouldn't be too hard to implement.

[...]

>
>>
>>> +                                     MMC_CAP2_NO_SD |
>>> +                                     MMC_CAP2_NO_SDIO;
>>
>> I think we need to update the DT documentation for mmc-card.
>> Typically, we should explicitly state what kind of other existing mmc
>> DT properties that will be automatically selected, when the mmc-card
>> is specified.
>>
>> Can you please look into updating this DT doc as well.
>>
>
>   Similar to above, may I keep it now and bring up another patch later
>   to update mmc-card DT and parsing?

Please, no.

[...]

Kind regards
Uffe
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Ulf Hansson Jan. 30, 2017, 9:10 a.m. UTC | #7
On 28 January 2017 at 09:16, Adrian Hunter <adrian.hunter@intel.com> wrote:
> On 27/01/2017 5:12 p.m., Ulf Hansson wrote:
>>
>> On 26 January 2017 at 13:39, Adrian Hunter <adrian.hunter@intel.com>
>> wrote:
>>>
>>> On 26/01/17 12:50, Ulf Hansson wrote:
>>>>
>>>> On 11 January 2017 at 18:19, Gregory CLEMENT
>>>> <gregory.clement@free-electrons.com> wrote:
>>>>>
>>>>> +                       priv->init_card_type = MMC_TYPE_MMC;
>>>>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>>>>> +
>>>>> +                       /*
>>>>> +                        * Force to clear BUS_TEST to
>>>>> +                        * skip bus_test_pre and bus_test_post
>>>>> +                        */
>>>>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>>>>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>>>>
>>>>
>>>> This cap is a bit strange. It was added several years ago by Adrian
>>>> Hunter, but I am wondering about the reason to why it's needed.
>>>>
>>>
>>> MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.
>>>
>>> I think it was added to enable people to choose whether they wanted a
>>> large
>>> or small erase granularity.  That probably doesn't matter if the card
>>> supports TRIM.
>>>
>>
>> Huh, the erase/trim/discard code in the mmc core is really hairy. :-)
>>
>> In mmc_calc_max_discard() the following code/comment exists:
>>
>> /*
>>  * Without erase_group_def set, MMC erase timeout depends on clock
>>  * frequence which can change.  In that case, the best choice is
>>  * just the preferred erase size.
>>  */
>> if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
>>      return card->pref_erase;
>>
>>
>> This makes me wonder.
>>
>> So, when we haven't enabled the high capacity erase groups in the
>> EXT_CSD register (ext_csd.erase_group_def), we will use the pref_erase
>> size.
>>
>> In the other case, as when having MMC_CAP2_HC_ERASE_SZ set (which will
>> set ext_csd.erase_group_def),  we will instead  do some calculations
>> to find out the max discards.
>>
>> Are you saying that these calculations doesn't matter much - or are
>> you saying that we always want to do them?
>
>
> No, I was saying that if you have TRIM then TRIM is preferred to ERASE so
> the erase group size does not come into play when discarding, since ERASE
> granularity is erase groups whereas TRIM granularity is sectors.

Right. Thanks for clarifying.

>
> However ERASE_GROUP_DEF also affects the size of write protect groups.

In either case.

What do you think of removing MMC_CAP2_HC_ERASE_SZ? I don't like these
kind of soft polices, it's better if we can decide on a common
behaviour - whatever that is.

Kind regards
Uffe
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Adrian Hunter Jan. 30, 2017, 9:40 a.m. UTC | #8
On 30/01/17 11:10, Ulf Hansson wrote:
> On 28 January 2017 at 09:16, Adrian Hunter <adrian.hunter@intel.com> wrote:
>> On 27/01/2017 5:12 p.m., Ulf Hansson wrote:
>>>
>>> On 26 January 2017 at 13:39, Adrian Hunter <adrian.hunter@intel.com>
>>> wrote:
>>>>
>>>> On 26/01/17 12:50, Ulf Hansson wrote:
>>>>>
>>>>> On 11 January 2017 at 18:19, Gregory CLEMENT
>>>>> <gregory.clement@free-electrons.com> wrote:
>>>>>>
>>>>>> +                       priv->init_card_type = MMC_TYPE_MMC;
>>>>>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>>>>>> +
>>>>>> +                       /*
>>>>>> +                        * Force to clear BUS_TEST to
>>>>>> +                        * skip bus_test_pre and bus_test_post
>>>>>> +                        */
>>>>>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>>>>>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>>>>>
>>>>>
>>>>> This cap is a bit strange. It was added several years ago by Adrian
>>>>> Hunter, but I am wondering about the reason to why it's needed.
>>>>>
>>>>
>>>> MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.
>>>>
>>>> I think it was added to enable people to choose whether they wanted a
>>>> large
>>>> or small erase granularity.  That probably doesn't matter if the card
>>>> supports TRIM.
>>>>
>>>
>>> Huh, the erase/trim/discard code in the mmc core is really hairy. :-)
>>>
>>> In mmc_calc_max_discard() the following code/comment exists:
>>>
>>> /*
>>>  * Without erase_group_def set, MMC erase timeout depends on clock
>>>  * frequence which can change.  In that case, the best choice is
>>>  * just the preferred erase size.
>>>  */
>>> if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
>>>      return card->pref_erase;
>>>
>>>
>>> This makes me wonder.
>>>
>>> So, when we haven't enabled the high capacity erase groups in the
>>> EXT_CSD register (ext_csd.erase_group_def), we will use the pref_erase
>>> size.
>>>
>>> In the other case, as when having MMC_CAP2_HC_ERASE_SZ set (which will
>>> set ext_csd.erase_group_def),  we will instead  do some calculations
>>> to find out the max discards.
>>>
>>> Are you saying that these calculations doesn't matter much - or are
>>> you saying that we always want to do them?
>>
>>
>> No, I was saying that if you have TRIM then TRIM is preferred to ERASE so
>> the erase group size does not come into play when discarding, since ERASE
>> granularity is erase groups whereas TRIM granularity is sectors.
> 
> Right. Thanks for clarifying.
> 
>>
>> However ERASE_GROUP_DEF also affects the size of write protect groups.
> 
> In either case.
> 
> What do you think of removing MMC_CAP2_HC_ERASE_SZ? I don't like these
> kind of soft polices, it's better if we can decide on a common
> behaviour - whatever that is.

Changing the value of ERASE_GROUP_DEF could be a problem, for example the
spec. says:

"Similarly if the host set ERASE_GROUP_DEF bit for a device that the default
write protect was already set in some of the area in the previous power
cycle, then the device may show unknown behavior when host issue write
or erase commands to the device. In application, it is mandatory for host to
use same ERASE GROUP DEF value to the device all the time."

Whether or not there is anyone that would actually be affected is hard to know.

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Ulf Hansson Jan. 30, 2017, 10:15 a.m. UTC | #9
On 30 January 2017 at 10:40, Adrian Hunter <adrian.hunter@intel.com> wrote:
> On 30/01/17 11:10, Ulf Hansson wrote:
>> On 28 January 2017 at 09:16, Adrian Hunter <adrian.hunter@intel.com> wrote:
>>> On 27/01/2017 5:12 p.m., Ulf Hansson wrote:
>>>>
>>>> On 26 January 2017 at 13:39, Adrian Hunter <adrian.hunter@intel.com>
>>>> wrote:
>>>>>
>>>>> On 26/01/17 12:50, Ulf Hansson wrote:
>>>>>>
>>>>>> On 11 January 2017 at 18:19, Gregory CLEMENT
>>>>>> <gregory.clement@free-electrons.com> wrote:
>>>>>>>
>>>>>>> +                       priv->init_card_type = MMC_TYPE_MMC;
>>>>>>> +                       mmc->caps |= MMC_CAP_NONREMOVABLE;
>>>>>>> +
>>>>>>> +                       /*
>>>>>>> +                        * Force to clear BUS_TEST to
>>>>>>> +                        * skip bus_test_pre and bus_test_post
>>>>>>> +                        */
>>>>>>> +                       mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>>>>>>> +                       mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>>>>>>
>>>>>>
>>>>>> This cap is a bit strange. It was added several years ago by Adrian
>>>>>> Hunter, but I am wondering about the reason to why it's needed.
>>>>>>
>>>>>
>>>>> MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.
>>>>>
>>>>> I think it was added to enable people to choose whether they wanted a
>>>>> large
>>>>> or small erase granularity.  That probably doesn't matter if the card
>>>>> supports TRIM.
>>>>>
>>>>
>>>> Huh, the erase/trim/discard code in the mmc core is really hairy. :-)
>>>>
>>>> In mmc_calc_max_discard() the following code/comment exists:
>>>>
>>>> /*
>>>>  * Without erase_group_def set, MMC erase timeout depends on clock
>>>>  * frequence which can change.  In that case, the best choice is
>>>>  * just the preferred erase size.
>>>>  */
>>>> if (mmc_card_mmc(card) && !(card->ext_csd.erase_group_def & 1))
>>>>      return card->pref_erase;
>>>>
>>>>
>>>> This makes me wonder.
>>>>
>>>> So, when we haven't enabled the high capacity erase groups in the
>>>> EXT_CSD register (ext_csd.erase_group_def), we will use the pref_erase
>>>> size.
>>>>
>>>> In the other case, as when having MMC_CAP2_HC_ERASE_SZ set (which will
>>>> set ext_csd.erase_group_def),  we will instead  do some calculations
>>>> to find out the max discards.
>>>>
>>>> Are you saying that these calculations doesn't matter much - or are
>>>> you saying that we always want to do them?
>>>
>>>
>>> No, I was saying that if you have TRIM then TRIM is preferred to ERASE so
>>> the erase group size does not come into play when discarding, since ERASE
>>> granularity is erase groups whereas TRIM granularity is sectors.
>>
>> Right. Thanks for clarifying.
>>
>>>
>>> However ERASE_GROUP_DEF also affects the size of write protect groups.
>>
>> In either case.
>>
>> What do you think of removing MMC_CAP2_HC_ERASE_SZ? I don't like these
>> kind of soft polices, it's better if we can decide on a common
>> behaviour - whatever that is.
>
> Changing the value of ERASE_GROUP_DEF could be a problem, for example the
> spec. says:
>
> "Similarly if the host set ERASE_GROUP_DEF bit for a device that the default
> write protect was already set in some of the area in the previous power
> cycle, then the device may show unknown behavior when host issue write
> or erase commands to the device. In application, it is mandatory for host to
> use same ERASE GROUP DEF value to the device all the time."
>
> Whether or not there is anyone that would actually be affected is hard to know.

Okay. I am going to submit a patch that just removes the behaviour for
MMC_CAP2_HC_ERASE_SZ and the cap itself.

The cap isn't particular widely used anyway. Let's see what people think of it.

Thanks a lot for you input!

Kind regards
Uffe
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Hu Ziji Jan. 30, 2017, 3:12 p.m. UTC | #10
Hi Ulf,

On 2017/1/30 16:41, Ulf Hansson wrote:
> [...]
> 
>>>> + */
>>>> +static int xenon_child_node_of_parse(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);
>>>> +       struct device_node *child;
>>>> +       int nr_child;
>>>> +
>>>> +       priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
>>>> +
>>>> +       nr_child = of_get_child_count(np);
>>>> +       if (!nr_child)
>>>> +               return 0;
>>>> +
>>>> +       for_each_child_of_node(np, child) {
>>>> +               if (of_device_is_compatible(child, "mmc-card")) {
>>>
>>> To avoid code from being duplicated, I would rather see the DT parsing
>>> of the child nodes for "mmc-card", to be done by the mmc core.
>>>
>>> As a matter of fact it is already being done, but perhaps we need to
>>> change that a bit as to fit your case.
>>>
>>> I suggest you have a look and see how to update this in the core,
>>> instead of doing it here in the host driver.
>>>
>>
>>     I understand your concern.
>>
>>     It seems that so far "mmc-card" is only used in our Xenon driver.
> 
> git grep "mmc-card" tells you more about where it's being parsed by
> the mmc core.
> 
>>     Besides, we set Xenon specific parameters and attributions when
>>     parsing "mmc-card" property.
> 
> I don't see any Xenon specific properties.
> 
> Instead I think it would make sense to update the generic
> interpretation of the binding for mmc-card, as you have done here.
> 

   OK. I will merge it into core layer.
 
   Our Xenon driver requires to determine whether current SDHC is
   for eMMC before card init. Thus I would like to implement a specific
   function for mmc-card parsing in mmc.c and let mmc_of_parse() in host.c
   to call it.
   But there are some detailed issues then.
   1. mmc_decode_ext_csd() also parses mmc-card to check broken-hpi.
      So mmc-card parse will still be duplicated.
      Shall we merge broken-hpi check into mmc-card parse?
      It might require a new flag to indicate broken-hpi attribution in
      mmc_host structure.

   2. Structure mmc_card is not ready while parsing mmc-card.
      Thus we are not able to indicate card type in mmc_card.
      As a result, our Xenon specific parse function still has to
      parse mmc-card again to check if eMMC card is in used.

   Could you please help suggest any better place in core layer to
   parse mmc-card?

   Thank you.

Best regards,
Hu Ziji

>>
>>     May I keep current implementation?
> 
> Rather not. Let's try to make the parsing of the child node for
> mmc-card generic.
> 
>>     In my very own opinion, moving it into core layer should be another
>>     independent patch.
> 
> Absolutely an independent patch. Whether it can be done as a part of
> mmc_of_parse() or whether we need yet another new mmc_of* API, we can
> discuss.
> 
> My point is that, I don't this to be specific for Xenon (unless there
> are specific reason, which I don't see here).
> 
>>     And it will also cost some more time. To be honest, it is difficult
>>     for me to bring up a generic core layer implementation to parse
>>     "mmc-card", since I'm not clear about other vendor's requirement.
> 
> Well, then you need to learn more about how the mmc core works. In
> this case, it shouldn't be too hard to implement.
> 
> [...]
> 
>>
>>>
>>>> +                                     MMC_CAP2_NO_SD |
>>>> +                                     MMC_CAP2_NO_SDIO;
>>>
>>> I think we need to update the DT documentation for mmc-card.
>>> Typically, we should explicitly state what kind of other existing mmc
>>> DT properties that will be automatically selected, when the mmc-card
>>> is specified.
>>>
>>> Can you please look into updating this DT doc as well.
>>>
>>
>>   Similar to above, may I keep it now and bring up another patch later
>>   to update mmc-card DT and parsing?
> 
> Please, no.
> 
> [...]
> 
> Kind regards
> Uffe
> 
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diff mbox

Patch

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 2eb97014dc3f..8d2d08de14a0 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 && 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..0e0c60892f72
--- /dev/null
+++ b/drivers/mmc/host/sdhci-xenon.c
@@ -0,0 +1,631 @@ 
+/*
+ * Driver for Marvell Xenon SDHC as a platform device
+ *
+ * Copyright (C) 2016 Marvell, All Rights Reserved.
+ *
+ * Author:	Hu Ziji <huziji@marvell.com>
+ * 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@marvell.com>
+ * 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);
+	}
+
+	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);
+}
+
+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);
+	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;
+
+		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
+		 * 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 child node in Xenon DT.
+ * Search for the following item(s):
+ * - eMMC card type
+ */
+static int xenon_child_node_of_parse(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);
+	struct device_node *child;
+	int nr_child;
+
+	priv->init_card_type = XENON_CARD_TYPE_UNKNOWN;
+
+	nr_child = of_get_child_count(np);
+	if (!nr_child)
+		return 0;
+
+	for_each_child_of_node(np, child) {
+		if (of_device_is_compatible(child, "mmc-card"))	{
+			priv->init_card_type = MMC_TYPE_MMC;
+			mmc->caps |= MMC_CAP_NONREMOVABLE;
+
+			/*
+			 * Force to clear BUS_TEST to
+			 * skip bus_test_pre and bus_test_post
+			 */
+			mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
+			mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
+				      MMC_CAP2_PACKED_CMD |
+				      MMC_CAP2_NO_SD |
+				      MMC_CAP2_NO_SDIO;
+		}
+	}
+
+	return 0;
+}
+
+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);
+	int err;
+	u32 sdhc_id, nr_sdhc;
+	u32 tuning_count;
+
+	/* Standard MMC property */
+	err = mmc_of_parse(mmc);
+	if (err)
+		return err;
+
+	/* Standard SDHCI property */
+	sdhci_get_of_property(pdev);
+
+	/*
+	 * Xenon Specific property:
+	 * 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
+	 */
+	/* Parse child node, including checking emmc type */
+	err = xenon_child_node_of_parse(pdev);
+	if (err)
+		return err;
+
+	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 err;
+}
+
+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 = 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-8k-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@marvell.com>");
+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@marvell.com>
+ * 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