diff mbox

[v3,1/4] mmc: dw_mmc: exynos: incorporate ciu_div into timing property

Message ID 1420008185-24758-2-git-send-email-alim.akhtar@samsung.com
State New, archived
Headers show

Commit Message

Alim Akhtar Dec. 31, 2014, 6:43 a.m. UTC
From: Seungwon Jeon <tgih.jun@samsung.com>

ciu_div may not be common value for all speed mode.
So, it needs to be attached to CLKSEL timing.
This also introduce a new compatibale 'dw-mshc-hs200-timing'
for selecting hs200 timing value

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
---
 .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
 drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
 drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
 3 files changed, 67 insertions(+), 30 deletions(-)

Comments

Ulf Hansson Jan. 2, 2015, 10:30 a.m. UTC | #1
On 31 December 2014 at 07:43, Alim Akhtar <alim.akhtar@samsung.com> wrote:
> From: Seungwon Jeon <tgih.jun@samsung.com>
>
> ciu_div may not be common value for all speed mode.
> So, it needs to be attached to CLKSEL timing.
> This also introduce a new compatibale 'dw-mshc-hs200-timing'
> for selecting hs200 timing value

According to the patch you are adding a new DT property not a
"compatible". Please update the commit message.

The rest looks good to me.

Kind regards
Uffe

>
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> ---
>  .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
>  drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
>  drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
>  3 files changed, 67 insertions(+), 30 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> index ee4fc05..06455de 100644
> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> @@ -23,10 +23,6 @@ Required Properties:
>         - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
>           specific extensions having an SMU.
>
> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
> -  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> -  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
> -
>  * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
>    in transmit mode and CIU clock phase shift value in receive mode for single
>    data rate mode operation. Refer notes below for the order of the cells and the
> @@ -37,11 +33,16 @@ Required Properties:
>    data rate mode operation. Refer notes below for the order of the cells and the
>    valid values.
>
> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
> +
>    Notes for the sdr-timing and ddr-timing values:
>
>      The order of the cells should be
>        - First Cell: CIU clock phase shift value for tx mode.
>        - Second Cell: CIU clock phase shift value for rx mode.
> +      - Thrid Cell: Specifies the divider value for the card interface
> +        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> +        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>
>      Valid values for SDR and DDR CIU clock timing for Exynos5250:
>        - valid value for tx phase shift and rx phase shift is 0 to 7.
> @@ -79,8 +80,8 @@ Example:
>                 broken-cd;
>                 fifo-depth = <0x80>;
>                 card-detect-delay = <200>;
> -               samsung,dw-mshc-ciu-div = <3>;
> -               samsung,dw-mshc-sdr-timing = <2 3>;
> -               samsung,dw-mshc-ddr-timing = <1 2>;
> +               samsung,dw-mshc-sdr-timing = <2 3 3>;
> +               samsung,dw-mshc-ddr-timing = <1 2 3>;
> +               samsung,dw-mshc-hs200-timing = <0 2 3>;
>                 bus-width = <8>;
>         };
> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index 12a5eaa..be6530e 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -40,6 +40,7 @@ struct dw_mci_exynos_priv_data {
>         u8                              ciu_div;
>         u32                             sdr_timing;
>         u32                             ddr_timing;
> +       u32                             hs200_timing;
>         u32                             cur_speed;
>  };
>
> @@ -71,6 +72,21 @@ static struct dw_mci_exynos_compatible {
>         },
>  };
>
> +static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
> +{
> +       struct dw_mci_exynos_priv_data *priv = host->priv;
> +
> +       if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> +               return EXYNOS4412_FIXED_CIU_CLK_DIV;
> +       else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> +               return EXYNOS4210_FIXED_CIU_CLK_DIV;
> +       else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> +                       priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> +               return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
> +       else
> +               return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
> +}
> +
>  static int dw_mci_exynos_priv_init(struct dw_mci *host)
>  {
>         struct dw_mci_exynos_priv_data *priv = host->priv;
> @@ -85,6 +101,8 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
>                            SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
>         }
>
> +       priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
> +
>         return 0;
>  }
>
> @@ -92,7 +110,7 @@ static int dw_mci_exynos_setup_clock(struct dw_mci *host)
>  {
>         struct dw_mci_exynos_priv_data *priv = host->priv;
>
> -       host->bus_hz /= (priv->ciu_div + 1);
> +       host->bus_hz /= priv->ciu_div;
>
>         return 0;
>  }
> @@ -177,9 +195,14 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>         struct dw_mci_exynos_priv_data *priv = host->priv;
>         unsigned int wanted = ios->clock;
>         unsigned long actual;
> -       u8 div = priv->ciu_div + 1;
>
> -       if (ios->timing == MMC_TIMING_MMC_DDR52) {
> +       if (ios->timing == MMC_TIMING_MMC_HS200) {
> +               if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> +                       priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> +                       mci_writel(host, CLKSEL64, priv->hs200_timing);
> +               else
> +                       mci_writel(host, CLKSEL, priv->hs200_timing);
> +       } else if (ios->timing == MMC_TIMING_MMC_DDR52) {
>                 if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
>                         priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
>                         mci_writel(host, CLKSEL64, priv->ddr_timing);
> @@ -208,6 +231,7 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>                 wanted = EXYNOS_CCLKIN_MIN;
>
>         if (wanted != priv->cur_speed) {
> +               u8 div = dw_mci_exynos_get_ciu_div(host);
>                 int ret = clk_set_rate(host->ciu_clk, wanted * div);
>                 if (ret)
>                         dev_warn(host->dev,
> @@ -220,14 +244,34 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>         }
>  }
>
> +static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
> +                                           unsigned int ctrl_type,
> +                                           const char *propname,
> +                                           u32 *out_values)
> +{
> +       struct device_node *np = host->dev->of_node;
> +       u32 timing[3];
> +       int ret;
> +
> +       ret = of_property_read_u32_array(np, propname, timing, 3);
> +       if (ret)
> +               return ret;
> +
> +       if (ctrl_type == DW_MCI_TYPE_EXYNOS4412 ||
> +           ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> +               timing[2] = 0;
> +
> +       *out_values = SDMMC_CLKSEL_TIMING(timing[0], timing[1], timing[2]);
> +
> +       return 0;
> +}
> +
> +
>  static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>  {
>         struct dw_mci_exynos_priv_data *priv;
>         struct device_node *np = host->dev->of_node;
> -       u32 timing[2];
> -       u32 div = 0;
> -       int idx;
> -       int ret;
> +       int idx, ret;
>
>         priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
>         if (!priv)
> @@ -238,29 +282,20 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>                         priv->ctrl_type = exynos_compat[idx].ctrl_type;
>         }
>
> -       if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> -               priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
> -       else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> -               priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
> -       else {
> -               of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
> -               priv->ciu_div = div;
> -       }
> -
> -       ret = of_property_read_u32_array(np,
> -                       "samsung,dw-mshc-sdr-timing", timing, 2);
> +       ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +                       "samsung,dw-mshc-sdr-timing", &priv->sdr_timing);
>         if (ret)
>                 return ret;
>
> -       priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> -
> -       ret = of_property_read_u32_array(np,
> -                       "samsung,dw-mshc-ddr-timing", timing, 2);
> +       ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +                       "samsung,dw-mshc-ddr-timing", &priv->ddr_timing);
>         if (ret)
>                 return ret;
>
> -       priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> +       dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +               "samsung,dw-mshc-hs200-timing", &priv->hs200_timing);
>         host->priv = priv;
> +
>         return 0;
>  }
>
> diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
> index 7872ce5..c04ecef 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.h
> +++ b/drivers/mmc/host/dw_mmc-exynos.h
> @@ -21,6 +21,7 @@
>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)     (((x) & 7) << 16)
>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)   (((x) & 7) << 24)
>  #define SDMMC_CLKSEL_GET_DRV_WD3(x)    (((x) >> 16) & 0x7)
> +#define SDMMC_CLKSEL_GET_DIV(x)                (((x) >> 24) & 0x7)
>  #define SDMMC_CLKSEL_TIMING(x, y, z)   (SDMMC_CLKSEL_CCLK_SAMPLE(x) |  \
>                                          SDMMC_CLKSEL_CCLK_DRIVE(y) |   \
>                                          SDMMC_CLKSEL_CCLK_DIVIDER(z))
> --
> 1.7.9.5
>
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Doug Anderson Jan. 2, 2015, 4:58 p.m. UTC | #2
Alim,

On Tue, Dec 30, 2014 at 10:43 PM, Alim Akhtar <alim.akhtar@samsung.com> wrote:
> From: Seungwon Jeon <tgih.jun@samsung.com>
>
> ciu_div may not be common value for all speed mode.
> So, it needs to be attached to CLKSEL timing.

The more time I've spent looking at all of this stuff the less I like
the exynos bindings.  Personally I'd prefer to see the exynos bindings
fixed rather than go further down the path of these bindings.

Specifically:

1. The "drive" really should be specified quite differently.
According to the DesignWare docs, the "drive" phase is there to meet
hold time requirements.  Hold time requirements are different for
different SD/MMC modes and are specified in nanoseconds (SDR104 is
.8ns, ID mode is 5.0ns).  There is a per-SoC parameter needed that
indicates some built-in delay (in nanoseconds) and that shouldn't
change based on clock speed or card mode.

2. The ciu_div really ought to be automatic.  Start out at a divide by
4.  If you end up with both drive and sample at phases of 0, 90, 180,
270 then you can change to divide by 2.

I still haven't looked at every last detail of these delays though, so
please correct me if I'm wrong.  I've added Alex who may have looked
at this more than I have.


With all of the above, there's also the fact that (I think) we should
be moving towards working with the clock phase API since all of your
values are effectively specifying clock phases, just in a very arcane
way.


> This also introduce a new compatibale 'dw-mshc-hs200-timing'
> for selecting hs200 timing value

As per above, I don't think this is needed.


> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> ---
>  .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
>  drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
>  drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
>  3 files changed, 67 insertions(+), 30 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> index ee4fc05..06455de 100644
> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> @@ -23,10 +23,6 @@ Required Properties:
>         - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
>           specific extensions having an SMU.
>
> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
> -  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> -  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
> -
>  * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
>    in transmit mode and CIU clock phase shift value in receive mode for single
>    data rate mode operation. Refer notes below for the order of the cells and the
> @@ -37,11 +33,16 @@ Required Properties:
>    data rate mode operation. Refer notes below for the order of the cells and the
>    valid values.
>
> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
> +
>    Notes for the sdr-timing and ddr-timing values:
>
>      The order of the cells should be
>        - First Cell: CIU clock phase shift value for tx mode.
>        - Second Cell: CIU clock phase shift value for rx mode.
> +      - Thrid Cell: Specifies the divider value for the card interface
> +        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> +        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>
>      Valid values for SDR and DDR CIU clock timing for Exynos5250:
>        - valid value for tx phase shift and rx phase shift is 0 to 7.
> @@ -79,8 +80,8 @@ Example:
>                 broken-cd;
>                 fifo-depth = <0x80>;
>                 card-detect-delay = <200>;
> -               samsung,dw-mshc-ciu-div = <3>;
> -               samsung,dw-mshc-sdr-timing = <2 3>;
> -               samsung,dw-mshc-ddr-timing = <1 2>;
> +               samsung,dw-mshc-sdr-timing = <2 3 3>;
> +               samsung,dw-mshc-ddr-timing = <1 2 3>;
> +               samsung,dw-mshc-hs200-timing = <0 2 3>;

You are breaking backward compatibility here.  If your change is
merged then all old boards will instantly break.  Since the "dts" and
code changes will likely be merged through different trees you'll end
up with a bunch of broken trees until everything is merged together.
Even if you don't subscribe to the stable bindings theory this is not
acceptable.

-Doug
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Alim Akhtar Jan. 4, 2015, 10:43 p.m. UTC | #3
Hi Doug,
Thanks for looking into this series.

On Fri, Jan 2, 2015 at 10:28 PM, Doug Anderson <dianders@chromium.org> wrote:
> Alim,
>
> On Tue, Dec 30, 2014 at 10:43 PM, Alim Akhtar <alim.akhtar@samsung.com> wrote:
>> From: Seungwon Jeon <tgih.jun@samsung.com>
>>
>> ciu_div may not be common value for all speed mode.
>> So, it needs to be attached to CLKSEL timing.
>
> The more time I've spent looking at all of this stuff the less I like
> the exynos bindings.  Personally I'd prefer to see the exynos bindings
> fixed rather than go further down the path of these bindings.
>
> Specifically:
>
> 1. The "drive" really should be specified quite differently.
> According to the DesignWare docs, the "drive" phase is there to meet
> hold time requirements.  Hold time requirements are different for
> different SD/MMC modes and are specified in nanoseconds (SDR104 is
> .8ns, ID mode is 5.0ns).  There is a per-SoC parameter needed that
> indicates some built-in delay (in nanoseconds) and that shouldn't
> change based on clock speed or card mode.
>
Yes, "drive" phase shift are there to meet hold time requirements. And
that why we in general don't change it as those are fixed for a
SoC/Board based on actual measurement of the same.

> 2. The ciu_div really ought to be automatic.  Start out at a divide by
> 4.  If you end up with both drive and sample at phases of 0, 90, 180,
> 270 then you can change to divide by 2.
>
> I still haven't looked at every last detail of these delays though, so
> please correct me if I'm wrong.  I've added Alex who may have looked
> at this more than I have.
>
Thanks, suggestions/comments are welcome.
>
> With all of the above, there's also the fact that (I think) we should
> be moving towards working with the clock phase API since all of your
> values are effectively specifying clock phases, just in a very arcane
> way.
>
That is something nice to have, and should be done at some point.
As you know exynos implements a custom register called CLKSEL, and it
allows us to set the required "sample" phase shift. And exynos uses
"variable delay tuning" as per DW databook to set "sample" phase shift
based on tuning data.
>
>> This also introduce a new compatibale 'dw-mshc-hs200-timing'
>> for selecting hs200 timing value
>
> As per above, I don't think this is needed.
>
>
>> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
>> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
>> ---
>>  .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
>>  drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
>>  drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
>>  3 files changed, 67 insertions(+), 30 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> index ee4fc05..06455de 100644
>> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> @@ -23,10 +23,6 @@ Required Properties:
>>         - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
>>           specific extensions having an SMU.
>>
>> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
>> -  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
>> -  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>> -
>>  * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
>>    in transmit mode and CIU clock phase shift value in receive mode for single
>>    data rate mode operation. Refer notes below for the order of the cells and the
>> @@ -37,11 +33,16 @@ Required Properties:
>>    data rate mode operation. Refer notes below for the order of the cells and the
>>    valid values.
>>
>> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
>> +
>>    Notes for the sdr-timing and ddr-timing values:
>>
>>      The order of the cells should be
>>        - First Cell: CIU clock phase shift value for tx mode.
>>        - Second Cell: CIU clock phase shift value for rx mode.
>> +      - Thrid Cell: Specifies the divider value for the card interface
>> +        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
>> +        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>>
>>      Valid values for SDR and DDR CIU clock timing for Exynos5250:
>>        - valid value for tx phase shift and rx phase shift is 0 to 7.
>> @@ -79,8 +80,8 @@ Example:
>>                 broken-cd;
>>                 fifo-depth = <0x80>;
>>                 card-detect-delay = <200>;
>> -               samsung,dw-mshc-ciu-div = <3>;
>> -               samsung,dw-mshc-sdr-timing = <2 3>;
>> -               samsung,dw-mshc-ddr-timing = <1 2>;
>> +               samsung,dw-mshc-sdr-timing = <2 3 3>;
>> +               samsung,dw-mshc-ddr-timing = <1 2 3>;
>> +               samsung,dw-mshc-hs200-timing = <0 2 3>;
>
> You are breaking backward compatibility here.  If your change is
> merged then all old boards will instantly break.  Since the "dts" and
> code changes will likely be merged through different trees you'll end
> up with a bunch of broken trees until everything is merged together.
> Even if you don't subscribe to the stable bindings theory this is not
> acceptable.
>
yes the major concern in this series is probably this, which breaks
things unless everything merge in one go and via one tree. Thats why I
re-based everything including dts change on mmc-tree for this case and
added device-tree mailing list for more opinion etc.

> -Doug
Doug Anderson Jan. 6, 2015, 1:07 a.m. UTC | #4
Alim,

On Sun, Jan 4, 2015 at 2:43 PM, Alim Akhtar <alim.akhtar@gmail.com> wrote:
>> You are breaking backward compatibility here.  If your change is
>> merged then all old boards will instantly break.  Since the "dts" and
>> code changes will likely be merged through different trees you'll end
>> up with a bunch of broken trees until everything is merged together.
>> Even if you don't subscribe to the stable bindings theory this is not
>> acceptable.
>>
> yes the major concern in this series is probably this, which breaks
> things unless everything merge in one go and via one tree. Thats why I
> re-based everything including dts change on mmc-tree for this case and
> added device-tree mailing list for more opinion etc.

Got it.  I doubt that folks will like this, but I could be wrong.  In
order for this to work, you'd need all changes in the series to land
in _both_ the ARMSoC tree and the MMC tree.  That's not unheard of,
but it doesn't seem ideal.

You also break bisect-ability here since without the code the DTS
change will break things and without the DTS change the code will
break things.

If you add all the above to the fact that bindings are supposed to be
stable (ish) I'm not convinced this will land.


-Doug
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Jaehoon Chung Jan. 8, 2015, 1:36 a.m. UTC | #5
Hi, 

On 12/31/2014 03:43 PM, Alim Akhtar wrote:
> From: Seungwon Jeon <tgih.jun@samsung.com>
> 
> ciu_div may not be common value for all speed mode.
> So, it needs to be attached to CLKSEL timing.
> This also introduce a new compatibale 'dw-mshc-hs200-timing'
> for selecting hs200 timing value
> 
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> ---
>  .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
>  drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
>  drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
>  3 files changed, 67 insertions(+), 30 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> index ee4fc05..06455de 100644
> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
> @@ -23,10 +23,6 @@ Required Properties:
>  	- "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
>  	  specific extensions having an SMU.
>  
> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
> -  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> -  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
> -
>  * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
>    in transmit mode and CIU clock phase shift value in receive mode for single
>    data rate mode operation. Refer notes below for the order of the cells and the
> @@ -37,11 +33,16 @@ Required Properties:
>    data rate mode operation. Refer notes below for the order of the cells and the
>    valid values.
>  
> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.

What does this comment mean? "Similar with dw-mshc-sdr-timing"
how about adding the comment "optional"?

And i think this timing doesn't need, we can reuse the sdr-timing or ddr-timing.
Because it's re-configurated at tuning time, isn't?

> +
>    Notes for the sdr-timing and ddr-timing values:
>  
>      The order of the cells should be
>        - First Cell: CIU clock phase shift value for tx mode.
>        - Second Cell: CIU clock phase shift value for rx mode.
> +      - Thrid Cell: Specifies the divider value for the card interface
> +        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
> +        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>  
>      Valid values for SDR and DDR CIU clock timing for Exynos5250:
>        - valid value for tx phase shift and rx phase shift is 0 to 7.
> @@ -79,8 +80,8 @@ Example:
>  		broken-cd;
>  		fifo-depth = <0x80>;
>  		card-detect-delay = <200>;
> -		samsung,dw-mshc-ciu-div = <3>;
> -		samsung,dw-mshc-sdr-timing = <2 3>;
> -		samsung,dw-mshc-ddr-timing = <1 2>;
> +		samsung,dw-mshc-sdr-timing = <2 3 3>;
> +		samsung,dw-mshc-ddr-timing = <1 2 3>;
> +		samsung,dw-mshc-hs200-timing = <0 2 3>;
>  		bus-width = <8>;
>  	};
> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index 12a5eaa..be6530e 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -40,6 +40,7 @@ struct dw_mci_exynos_priv_data {
>  	u8				ciu_div;
>  	u32				sdr_timing;
>  	u32				ddr_timing;
> +	u32				hs200_timing;
>  	u32				cur_speed;
>  };
>  
> @@ -71,6 +72,21 @@ static struct dw_mci_exynos_compatible {
>  	},
>  };
>  
> +static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
> +{
> +	struct dw_mci_exynos_priv_data *priv = host->priv;
> +
> +	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> +		return EXYNOS4412_FIXED_CIU_CLK_DIV;
> +	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> +		return EXYNOS4210_FIXED_CIU_CLK_DIV;
> +	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> +			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> +		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
> +	else
> +		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;

If need this, I think more readable that use the switch-case statement. how about?

       switch (priv->ctrl_type) {
       case DW_MCI_TYPE_EXYNOS4412:
                return EXYNOS4412_FIXED_CIU_CLK_DIV;
       case DW_MCI_TYPE_EXYNOS4210:
                return EXYNOS4210_FIXED_CIU_CLK_DIV;
       case DW_MCI_TYPE_EXYNOS7:
       case DW_MCI_TYPE_EXYNOS7_SMU:
                return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
       default:
                return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
       }


> +}
> +
>  static int dw_mci_exynos_priv_init(struct dw_mci *host)
>  {
>  	struct dw_mci_exynos_priv_data *priv = host->priv;
> @@ -85,6 +101,8 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
>  			   SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
>  	}
>  
> +	priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
> +
>  	return 0;
>  }
>  
> @@ -92,7 +110,7 @@ static int dw_mci_exynos_setup_clock(struct dw_mci *host)
>  {
>  	struct dw_mci_exynos_priv_data *priv = host->priv;
>  
> -	host->bus_hz /= (priv->ciu_div + 1);
> +	host->bus_hz /= priv->ciu_div;
>  
>  	return 0;
>  }
> @@ -177,9 +195,14 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>  	struct dw_mci_exynos_priv_data *priv = host->priv;
>  	unsigned int wanted = ios->clock;
>  	unsigned long actual;
> -	u8 div = priv->ciu_div + 1;
>  
> -	if (ios->timing == MMC_TIMING_MMC_DDR52) {
> +	if (ios->timing == MMC_TIMING_MMC_HS200) {
> +		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
> +			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
> +			mci_writel(host, CLKSEL64, priv->hs200_timing);
> +		else
> +			mci_writel(host, CLKSEL, priv->hs200_timing);
> +	} else if (ios->timing == MMC_TIMING_MMC_DDR52) {
>  		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
>  			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
>  			mci_writel(host, CLKSEL64, priv->ddr_timing);
> @@ -208,6 +231,7 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>  		wanted = EXYNOS_CCLKIN_MIN;
>  
>  	if (wanted != priv->cur_speed) {
> +		u8 div = dw_mci_exynos_get_ciu_div(host);
>  		int ret = clk_set_rate(host->ciu_clk, wanted * div);
>  		if (ret)
>  			dev_warn(host->dev,
> @@ -220,14 +244,34 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>  	}
>  }
>  
> +static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
> +					    unsigned int ctrl_type,
> +					    const char *propname,
> +					    u32 *out_values)
> +{
> +	struct device_node *np = host->dev->of_node;
> +	u32 timing[3];
> +	int ret;
> +
> +	ret = of_property_read_u32_array(np, propname, timing, 3);
> +	if (ret)
> +		return ret;
> +
> +	if (ctrl_type == DW_MCI_TYPE_EXYNOS4412 ||
> +	    ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> +		timing[2] = 0;

Is it set to 0 into dt-file?

> +
> +	*out_values = SDMMC_CLKSEL_TIMING(timing[0], timing[1], timing[2]);
> +
> +	return 0;
> +}
> +
> +
>  static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>  {
>  	struct dw_mci_exynos_priv_data *priv;
>  	struct device_node *np = host->dev->of_node;
> -	u32 timing[2];
> -	u32 div = 0;
> -	int idx;
> -	int ret;
> +	int idx, ret;
>  
>  	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
>  	if (!priv)
> @@ -238,29 +282,20 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>  			priv->ctrl_type = exynos_compat[idx].ctrl_type;
>  	}
>  
> -	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
> -		priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
> -	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
> -		priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
> -	else {
> -		of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
> -		priv->ciu_div = div;
> -	}
> -
> -	ret = of_property_read_u32_array(np,
> -			"samsung,dw-mshc-sdr-timing", timing, 2);
> +	ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +			"samsung,dw-mshc-sdr-timing", &priv->sdr_timing);
>  	if (ret)
>  		return ret;
>  
> -	priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> -
> -	ret = of_property_read_u32_array(np,
> -			"samsung,dw-mshc-ddr-timing", timing, 2);
> +	ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +			"samsung,dw-mshc-ddr-timing", &priv->ddr_timing);
>  	if (ret)
>  		return ret;
>  
> -	priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
> +	dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
> +		"samsung,dw-mshc-hs200-timing", &priv->hs200_timing);

hs200-timing is optional, so it needs not to check return value, right?

Best Regards,
Jaehoon Chung

>  	host->priv = priv;
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
> index 7872ce5..c04ecef 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.h
> +++ b/drivers/mmc/host/dw_mmc-exynos.h
> @@ -21,6 +21,7 @@
>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)	(((x) & 7) << 16)
>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x)	(((x) & 7) << 24)
>  #define SDMMC_CLKSEL_GET_DRV_WD3(x)	(((x) >> 16) & 0x7)
> +#define SDMMC_CLKSEL_GET_DIV(x)		(((x) >> 24) & 0x7)
>  #define SDMMC_CLKSEL_TIMING(x, y, z)	(SDMMC_CLKSEL_CCLK_SAMPLE(x) |	\
>  					 SDMMC_CLKSEL_CCLK_DRIVE(y) |	\
>  					 SDMMC_CLKSEL_CCLK_DIVIDER(z))
> 

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Alim Akhtar Jan. 12, 2015, 1:52 p.m. UTC | #6
Hi Doug,

On Tue, Jan 6, 2015 at 6:37 AM, Doug Anderson <dianders@chromium.org> wrote:
> Alim,
>
> On Sun, Jan 4, 2015 at 2:43 PM, Alim Akhtar <alim.akhtar@gmail.com> wrote:
>>> You are breaking backward compatibility here.  If your change is
>>> merged then all old boards will instantly break.  Since the "dts" and
>>> code changes will likely be merged through different trees you'll end
>>> up with a bunch of broken trees until everything is merged together.
>>> Even if you don't subscribe to the stable bindings theory this is not
>>> acceptable.
>>>
>> yes the major concern in this series is probably this, which breaks
>> things unless everything merge in one go and via one tree. Thats why I
>> re-based everything including dts change on mmc-tree for this case and
>> added device-tree mailing list for more opinion etc.
>
> Got it.  I doubt that folks will like this, but I could be wrong.  In
> order for this to work, you'd need all changes in the series to land
> in _both_ the ARMSoC tree and the MMC tree.  That's not unheard of,
> but it doesn't seem ideal.
>
> You also break bisect-ability here since without the code the DTS
> change will break things and without the DTS change the code will
> break things.
>
> If you add all the above to the fact that bindings are supposed to be
> stable (ish) I'm not convinced this will land.
>
Hmmm......Ok, let me take a re-look on this, I will try to use
existing bindings.
>
> -Doug
Alim Akhtar Jan. 12, 2015, 1:55 p.m. UTC | #7
Hi Jaehoon,

On Thu, Jan 8, 2015 at 7:06 AM, Jaehoon Chung <jh80.chung@samsung.com> wrote:
> Hi,
>
> On 12/31/2014 03:43 PM, Alim Akhtar wrote:
>> From: Seungwon Jeon <tgih.jun@samsung.com>
>>
>> ciu_div may not be common value for all speed mode.
>> So, it needs to be attached to CLKSEL timing.
>> This also introduce a new compatibale 'dw-mshc-hs200-timing'
>> for selecting hs200 timing value
>>
>> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
>> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
>> ---
>>  .../devicetree/bindings/mmc/exynos-dw-mshc.txt     |   15 ++--
>>  drivers/mmc/host/dw_mmc-exynos.c                   |   81 ++++++++++++++------
>>  drivers/mmc/host/dw_mmc-exynos.h                   |    1 +
>>  3 files changed, 67 insertions(+), 30 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> index ee4fc05..06455de 100644
>> --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
>> @@ -23,10 +23,6 @@ Required Properties:
>>       - "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
>>         specific extensions having an SMU.
>>
>> -* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
>> -  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
>> -  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>> -
>>  * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
>>    in transmit mode and CIU clock phase shift value in receive mode for single
>>    data rate mode operation. Refer notes below for the order of the cells and the
>> @@ -37,11 +33,16 @@ Required Properties:
>>    data rate mode operation. Refer notes below for the order of the cells and the
>>    valid values.
>>
>> +* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
>
> What does this comment mean? "Similar with dw-mshc-sdr-timing"
> how about adding the comment "optional"?
>
> And i think this timing doesn't need, we can reuse the sdr-timing or ddr-timing.
> Because it's re-configurated at tuning time, isn't?
>
Ok, I will rework/drop this patch, I will try to use existing binding
as much as mush possible.
>> +
>>    Notes for the sdr-timing and ddr-timing values:
>>
>>      The order of the cells should be
>>        - First Cell: CIU clock phase shift value for tx mode.
>>        - Second Cell: CIU clock phase shift value for rx mode.
>> +      - Thrid Cell: Specifies the divider value for the card interface
>> +        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
>> +        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
>>
>>      Valid values for SDR and DDR CIU clock timing for Exynos5250:
>>        - valid value for tx phase shift and rx phase shift is 0 to 7.
>> @@ -79,8 +80,8 @@ Example:
>>               broken-cd;
>>               fifo-depth = <0x80>;
>>               card-detect-delay = <200>;
>> -             samsung,dw-mshc-ciu-div = <3>;
>> -             samsung,dw-mshc-sdr-timing = <2 3>;
>> -             samsung,dw-mshc-ddr-timing = <1 2>;
>> +             samsung,dw-mshc-sdr-timing = <2 3 3>;
>> +             samsung,dw-mshc-ddr-timing = <1 2 3>;
>> +             samsung,dw-mshc-hs200-timing = <0 2 3>;
>>               bus-width = <8>;
>>       };
>> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
>> index 12a5eaa..be6530e 100644
>> --- a/drivers/mmc/host/dw_mmc-exynos.c
>> +++ b/drivers/mmc/host/dw_mmc-exynos.c
>> @@ -40,6 +40,7 @@ struct dw_mci_exynos_priv_data {
>>       u8                              ciu_div;
>>       u32                             sdr_timing;
>>       u32                             ddr_timing;
>> +     u32                             hs200_timing;
>>       u32                             cur_speed;
>>  };
>>
>> @@ -71,6 +72,21 @@ static struct dw_mci_exynos_compatible {
>>       },
>>  };
>>
>> +static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
>> +{
>> +     struct dw_mci_exynos_priv_data *priv = host->priv;
>> +
>> +     if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
>> +             return EXYNOS4412_FIXED_CIU_CLK_DIV;
>> +     else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
>> +             return EXYNOS4210_FIXED_CIU_CLK_DIV;
>> +     else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
>> +                     priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
>> +             return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
>> +     else
>> +             return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
>
> If need this, I think more readable that use the switch-case statement. how about?
>
>        switch (priv->ctrl_type) {
>        case DW_MCI_TYPE_EXYNOS4412:
>                 return EXYNOS4412_FIXED_CIU_CLK_DIV;
>        case DW_MCI_TYPE_EXYNOS4210:
>                 return EXYNOS4210_FIXED_CIU_CLK_DIV;
>        case DW_MCI_TYPE_EXYNOS7:
>        case DW_MCI_TYPE_EXYNOS7_SMU:
>                 return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
>        default:
>                 return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
>        }
>
>
>> +}
>> +
>>  static int dw_mci_exynos_priv_init(struct dw_mci *host)
>>  {
>>       struct dw_mci_exynos_priv_data *priv = host->priv;
>> @@ -85,6 +101,8 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
>>                          SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
>>       }
>>
>> +     priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
>> +
>>       return 0;
>>  }
>>
>> @@ -92,7 +110,7 @@ static int dw_mci_exynos_setup_clock(struct dw_mci *host)
>>  {
>>       struct dw_mci_exynos_priv_data *priv = host->priv;
>>
>> -     host->bus_hz /= (priv->ciu_div + 1);
>> +     host->bus_hz /= priv->ciu_div;
>>
>>       return 0;
>>  }
>> @@ -177,9 +195,14 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>>       struct dw_mci_exynos_priv_data *priv = host->priv;
>>       unsigned int wanted = ios->clock;
>>       unsigned long actual;
>> -     u8 div = priv->ciu_div + 1;
>>
>> -     if (ios->timing == MMC_TIMING_MMC_DDR52) {
>> +     if (ios->timing == MMC_TIMING_MMC_HS200) {
>> +             if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
>> +                     priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
>> +                     mci_writel(host, CLKSEL64, priv->hs200_timing);
>> +             else
>> +                     mci_writel(host, CLKSEL, priv->hs200_timing);
>> +     } else if (ios->timing == MMC_TIMING_MMC_DDR52) {
>>               if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
>>                       priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
>>                       mci_writel(host, CLKSEL64, priv->ddr_timing);
>> @@ -208,6 +231,7 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>>               wanted = EXYNOS_CCLKIN_MIN;
>>
>>       if (wanted != priv->cur_speed) {
>> +             u8 div = dw_mci_exynos_get_ciu_div(host);
>>               int ret = clk_set_rate(host->ciu_clk, wanted * div);
>>               if (ret)
>>                       dev_warn(host->dev,
>> @@ -220,14 +244,34 @@ static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
>>       }
>>  }
>>
>> +static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
>> +                                         unsigned int ctrl_type,
>> +                                         const char *propname,
>> +                                         u32 *out_values)
>> +{
>> +     struct device_node *np = host->dev->of_node;
>> +     u32 timing[3];
>> +     int ret;
>> +
>> +     ret = of_property_read_u32_array(np, propname, timing, 3);
>> +     if (ret)
>> +             return ret;
>> +
>> +     if (ctrl_type == DW_MCI_TYPE_EXYNOS4412 ||
>> +         ctrl_type == DW_MCI_TYPE_EXYNOS4210)
>> +             timing[2] = 0;
>
> Is it set to 0 into dt-file?
>
>> +
>> +     *out_values = SDMMC_CLKSEL_TIMING(timing[0], timing[1], timing[2]);
>> +
>> +     return 0;
>> +}
>> +
>> +
>>  static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>>  {
>>       struct dw_mci_exynos_priv_data *priv;
>>       struct device_node *np = host->dev->of_node;
>> -     u32 timing[2];
>> -     u32 div = 0;
>> -     int idx;
>> -     int ret;
>> +     int idx, ret;
>>
>>       priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
>>       if (!priv)
>> @@ -238,29 +282,20 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host)
>>                       priv->ctrl_type = exynos_compat[idx].ctrl_type;
>>       }
>>
>> -     if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
>> -             priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
>> -     else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
>> -             priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
>> -     else {
>> -             of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
>> -             priv->ciu_div = div;
>> -     }
>> -
>> -     ret = of_property_read_u32_array(np,
>> -                     "samsung,dw-mshc-sdr-timing", timing, 2);
>> +     ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
>> +                     "samsung,dw-mshc-sdr-timing", &priv->sdr_timing);
>>       if (ret)
>>               return ret;
>>
>> -     priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
>> -
>> -     ret = of_property_read_u32_array(np,
>> -                     "samsung,dw-mshc-ddr-timing", timing, 2);
>> +     ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
>> +                     "samsung,dw-mshc-ddr-timing", &priv->ddr_timing);
>>       if (ret)
>>               return ret;
>>
>> -     priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
>> +     dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
>> +             "samsung,dw-mshc-hs200-timing", &priv->hs200_timing);
>
> hs200-timing is optional, so it needs not to check return value, right?
>
> Best Regards,
> Jaehoon Chung
>
>>       host->priv = priv;
>> +
>>       return 0;
>>  }
>>
>> diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
>> index 7872ce5..c04ecef 100644
>> --- a/drivers/mmc/host/dw_mmc-exynos.h
>> +++ b/drivers/mmc/host/dw_mmc-exynos.h
>> @@ -21,6 +21,7 @@
>>  #define SDMMC_CLKSEL_CCLK_DRIVE(x)   (((x) & 7) << 16)
>>  #define SDMMC_CLKSEL_CCLK_DIVIDER(x) (((x) & 7) << 24)
>>  #define SDMMC_CLKSEL_GET_DRV_WD3(x)  (((x) >> 16) & 0x7)
>> +#define SDMMC_CLKSEL_GET_DIV(x)              (((x) >> 24) & 0x7)
>>  #define SDMMC_CLKSEL_TIMING(x, y, z) (SDMMC_CLKSEL_CCLK_SAMPLE(x) |  \
>>                                        SDMMC_CLKSEL_CCLK_DRIVE(y) |   \
>>                                        SDMMC_CLKSEL_CCLK_DIVIDER(z))
>>
>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
index ee4fc05..06455de 100644
--- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
+++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt
@@ -23,10 +23,6 @@  Required Properties:
 	- "samsung,exynos7-dw-mshc-smu": for controllers with Samsung Exynos7
 	  specific extensions having an SMU.
 
-* samsung,dw-mshc-ciu-div: Specifies the divider value for the card interface
-  unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
-  ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
-
 * samsung,dw-mshc-sdr-timing: Specifies the value of CIU clock phase shift value
   in transmit mode and CIU clock phase shift value in receive mode for single
   data rate mode operation. Refer notes below for the order of the cells and the
@@ -37,11 +33,16 @@  Required Properties:
   data rate mode operation. Refer notes below for the order of the cells and the
   valid values.
 
+* samsung,dw-mshc-hs200-timing: Similar with dw-mshc-sdr-timing.
+
   Notes for the sdr-timing and ddr-timing values:
 
     The order of the cells should be
       - First Cell: CIU clock phase shift value for tx mode.
       - Second Cell: CIU clock phase shift value for rx mode.
+      - Thrid Cell: Specifies the divider value for the card interface
+        unit (ciu) clock. This property is applicable only for Exynos5 SoC's and
+        ignored for Exynos4 SoC's. The valid range of divider value is 0 to 7.
 
     Valid values for SDR and DDR CIU clock timing for Exynos5250:
       - valid value for tx phase shift and rx phase shift is 0 to 7.
@@ -79,8 +80,8 @@  Example:
 		broken-cd;
 		fifo-depth = <0x80>;
 		card-detect-delay = <200>;
-		samsung,dw-mshc-ciu-div = <3>;
-		samsung,dw-mshc-sdr-timing = <2 3>;
-		samsung,dw-mshc-ddr-timing = <1 2>;
+		samsung,dw-mshc-sdr-timing = <2 3 3>;
+		samsung,dw-mshc-ddr-timing = <1 2 3>;
+		samsung,dw-mshc-hs200-timing = <0 2 3>;
 		bus-width = <8>;
 	};
diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 12a5eaa..be6530e 100644
--- a/drivers/mmc/host/dw_mmc-exynos.c
+++ b/drivers/mmc/host/dw_mmc-exynos.c
@@ -40,6 +40,7 @@  struct dw_mci_exynos_priv_data {
 	u8				ciu_div;
 	u32				sdr_timing;
 	u32				ddr_timing;
+	u32				hs200_timing;
 	u32				cur_speed;
 };
 
@@ -71,6 +72,21 @@  static struct dw_mci_exynos_compatible {
 	},
 };
 
+static inline u8 dw_mci_exynos_get_ciu_div(struct dw_mci *host)
+{
+	struct dw_mci_exynos_priv_data *priv = host->priv;
+
+	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
+		return EXYNOS4412_FIXED_CIU_CLK_DIV;
+	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
+		return EXYNOS4210_FIXED_CIU_CLK_DIV;
+	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
+		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL64)) + 1;
+	else
+		return SDMMC_CLKSEL_GET_DIV(mci_readl(host, CLKSEL)) + 1;
+}
+
 static int dw_mci_exynos_priv_init(struct dw_mci *host)
 {
 	struct dw_mci_exynos_priv_data *priv = host->priv;
@@ -85,6 +101,8 @@  static int dw_mci_exynos_priv_init(struct dw_mci *host)
 			   SDMMC_MPSCTRL_NON_SECURE_WRITE_BIT);
 	}
 
+	priv->ciu_div = dw_mci_exynos_get_ciu_div(host);
+
 	return 0;
 }
 
@@ -92,7 +110,7 @@  static int dw_mci_exynos_setup_clock(struct dw_mci *host)
 {
 	struct dw_mci_exynos_priv_data *priv = host->priv;
 
-	host->bus_hz /= (priv->ciu_div + 1);
+	host->bus_hz /= priv->ciu_div;
 
 	return 0;
 }
@@ -177,9 +195,14 @@  static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 	struct dw_mci_exynos_priv_data *priv = host->priv;
 	unsigned int wanted = ios->clock;
 	unsigned long actual;
-	u8 div = priv->ciu_div + 1;
 
-	if (ios->timing == MMC_TIMING_MMC_DDR52) {
+	if (ios->timing == MMC_TIMING_MMC_HS200) {
+		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
+			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
+			mci_writel(host, CLKSEL64, priv->hs200_timing);
+		else
+			mci_writel(host, CLKSEL, priv->hs200_timing);
+	} else if (ios->timing == MMC_TIMING_MMC_DDR52) {
 		if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS7 ||
 			priv->ctrl_type == DW_MCI_TYPE_EXYNOS7_SMU)
 			mci_writel(host, CLKSEL64, priv->ddr_timing);
@@ -208,6 +231,7 @@  static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 		wanted = EXYNOS_CCLKIN_MIN;
 
 	if (wanted != priv->cur_speed) {
+		u8 div = dw_mci_exynos_get_ciu_div(host);
 		int ret = clk_set_rate(host->ciu_clk, wanted * div);
 		if (ret)
 			dev_warn(host->dev,
@@ -220,14 +244,34 @@  static void dw_mci_exynos_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 	}
 }
 
+static int dw_mci_exynos_dt_populate_timing(struct dw_mci *host,
+					    unsigned int ctrl_type,
+					    const char *propname,
+					    u32 *out_values)
+{
+	struct device_node *np = host->dev->of_node;
+	u32 timing[3];
+	int ret;
+
+	ret = of_property_read_u32_array(np, propname, timing, 3);
+	if (ret)
+		return ret;
+
+	if (ctrl_type == DW_MCI_TYPE_EXYNOS4412 ||
+	    ctrl_type == DW_MCI_TYPE_EXYNOS4210)
+		timing[2] = 0;
+
+	*out_values = SDMMC_CLKSEL_TIMING(timing[0], timing[1], timing[2]);
+
+	return 0;
+}
+
+
 static int dw_mci_exynos_parse_dt(struct dw_mci *host)
 {
 	struct dw_mci_exynos_priv_data *priv;
 	struct device_node *np = host->dev->of_node;
-	u32 timing[2];
-	u32 div = 0;
-	int idx;
-	int ret;
+	int idx, ret;
 
 	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -238,29 +282,20 @@  static int dw_mci_exynos_parse_dt(struct dw_mci *host)
 			priv->ctrl_type = exynos_compat[idx].ctrl_type;
 	}
 
-	if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4412)
-		priv->ciu_div = EXYNOS4412_FIXED_CIU_CLK_DIV - 1;
-	else if (priv->ctrl_type == DW_MCI_TYPE_EXYNOS4210)
-		priv->ciu_div = EXYNOS4210_FIXED_CIU_CLK_DIV - 1;
-	else {
-		of_property_read_u32(np, "samsung,dw-mshc-ciu-div", &div);
-		priv->ciu_div = div;
-	}
-
-	ret = of_property_read_u32_array(np,
-			"samsung,dw-mshc-sdr-timing", timing, 2);
+	ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
+			"samsung,dw-mshc-sdr-timing", &priv->sdr_timing);
 	if (ret)
 		return ret;
 
-	priv->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
-
-	ret = of_property_read_u32_array(np,
-			"samsung,dw-mshc-ddr-timing", timing, 2);
+	ret = dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
+			"samsung,dw-mshc-ddr-timing", &priv->ddr_timing);
 	if (ret)
 		return ret;
 
-	priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div);
+	dw_mci_exynos_dt_populate_timing(host, priv->ctrl_type,
+		"samsung,dw-mshc-hs200-timing", &priv->hs200_timing);
 	host->priv = priv;
+
 	return 0;
 }
 
diff --git a/drivers/mmc/host/dw_mmc-exynos.h b/drivers/mmc/host/dw_mmc-exynos.h
index 7872ce5..c04ecef 100644
--- a/drivers/mmc/host/dw_mmc-exynos.h
+++ b/drivers/mmc/host/dw_mmc-exynos.h
@@ -21,6 +21,7 @@ 
 #define SDMMC_CLKSEL_CCLK_DRIVE(x)	(((x) & 7) << 16)
 #define SDMMC_CLKSEL_CCLK_DIVIDER(x)	(((x) & 7) << 24)
 #define SDMMC_CLKSEL_GET_DRV_WD3(x)	(((x) >> 16) & 0x7)
+#define SDMMC_CLKSEL_GET_DIV(x)		(((x) >> 24) & 0x7)
 #define SDMMC_CLKSEL_TIMING(x, y, z)	(SDMMC_CLKSEL_CCLK_SAMPLE(x) |	\
 					 SDMMC_CLKSEL_CCLK_DRIVE(y) |	\
 					 SDMMC_CLKSEL_CCLK_DIVIDER(z))