[PATCH] ARM: socfpga: dts: Add a ciu clock node for sdmmc

[PATCH] ARM: socfpga: dts: Add a ciu clock node for sdmmc

[dinguyen at opensource.altera.com]

From: Dinh Nguyen <dinguyen@opensource.altera.com>

The CIU(Card Interface Unit) clock is used by the dw_mmc IP to clock an SD
card. The ciu_clk is the sdmmc_clk passed through a fixed divider of 4. This patch
adds the ciu_clk node and makes the sdmmc_clk it's parent.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
---
 arch/arm/boot/dts/socfpga.dtsi | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
index d9176e6..25418ee 100644
--- a/arch/arm/boot/dts/socfpga.dtsi
+++ b/arch/arm/boot/dts/socfpga.dtsi
@@ -451,6 +451,14 @@
 						clk-phase = <0 135>;
 					};
 
+					ciu_clk: ciu_clk {
+						#clock-cells = <0>;
+						compatible = "altr,socfpga-gate-clk";
+						clocks = <&sdmmc_clk>;
+						clk-gate = <0xa0 8>;
+						fixed-divider = <4>;
+					};
+
 					nand_x_clk: nand_x_clk {
 						#clock-cells = <0>;
 						compatible = "altr,socfpga-gate-clk";
@@ -635,7 +643,7 @@
 			fifo-depth = <0x400>;
 			#address-cells = <1>;
 			#size-cells = <0>;
-			clocks = <&l4_mp_clk>, <&sdmmc_clk>;
+			clocks = <&l4_mp_clk>, <&ciu_clk>;
 			clock-names = "biu", "ciu";
 		};
 
-- 
2.2.1

[PATCH] ARM: socfpga: dts: Add a ciu clock node for sdmmc

[Steffen Trumtrar]

Hi!

dinguyen at opensource.altera.com writes:
> From: Dinh Nguyen <dinguyen@opensource.altera.com>
>
> The CIU(Card Interface Unit) clock is used by the dw_mmc IP to clock an SD
> card. The ciu_clk is the sdmmc_clk passed through a fixed divider of 4. This patch
> adds the ciu_clk node and makes the sdmmc_clk it's parent.
>
> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
> ---
>  arch/arm/boot/dts/socfpga.dtsi | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
> index d9176e6..25418ee 100644
> --- a/arch/arm/boot/dts/socfpga.dtsi
> +++ b/arch/arm/boot/dts/socfpga.dtsi
> @@ -451,6 +451,14 @@
>  						clk-phase = <0 135>;
>  					};
>  
> +					ciu_clk: ciu_clk {
> +						#clock-cells = <0>;
> +						compatible = "altr,socfpga-gate-clk";
> +						clocks = <&sdmmc_clk>;
> +						clk-gate = <0xa0 8>;
> +						fixed-divider = <4>;
> +					};
> +

Hm, is this correct? The clk-gate at 0xa0 is for the SDMMC_CLK, no?
Also, maybe the clock should be named "sdmmc_clk_divided" like in the
datasheet, so it is easier to find.

>  					nand_x_clk: nand_x_clk {
>  						#clock-cells = <0>;
>  						compatible = "altr,socfpga-gate-clk";
> @@ -635,7 +643,7 @@
>  			fifo-depth = <0x400>;
>  			#address-cells = <1>;
>  			#size-cells = <0>;
> -			clocks = <&l4_mp_clk>, <&sdmmc_clk>;
> +			clocks = <&l4_mp_clk>, <&ciu_clk>;
>  			clock-names = "biu", "ciu";
>  		};
>  

Regards,
Steffen

-- 
Pengutronix e.K.                           | Steffen Trumtrar            |
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[PATCH] ARM: socfpga: dts: Add a ciu clock node for sdmmc

[Dinh Nguyen]

Hi Steffen,

On 04/13/2015 03:10 AM, Steffen Trumtrar wrote:
> 
> Hi!
> 
> dinguyen at opensource.altera.com writes:
>> From: Dinh Nguyen <dinguyen@opensource.altera.com>
>>
>> The CIU(Card Interface Unit) clock is used by the dw_mmc IP to clock an SD
>> card. The ciu_clk is the sdmmc_clk passed through a fixed divider of 4. This patch
>> adds the ciu_clk node and makes the sdmmc_clk it's parent.
>>
>> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
>> ---
>>  arch/arm/boot/dts/socfpga.dtsi | 10 +++++++++-
>>  1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
>> index d9176e6..25418ee 100644
>> --- a/arch/arm/boot/dts/socfpga.dtsi
>> +++ b/arch/arm/boot/dts/socfpga.dtsi
>> @@ -451,6 +451,14 @@
>>  						clk-phase = <0 135>;
>>  					};
>>  
>> +					ciu_clk: ciu_clk {
>> +						#clock-cells = <0>;
>> +						compatible = "altr,socfpga-gate-clk";
>> +						clocks = <&sdmmc_clk>;
>> +						clk-gate = <0xa0 8>;
>> +						fixed-divider = <4>;
>> +					};
>> +
> 
> Hm, is this correct? The clk-gate at 0xa0 is for the SDMMC_CLK, no?
> Also, maybe the clock should be named "sdmmc_clk_divided" like in the
> datasheet, so it is easier to find.
> 

Well, I didn't want to go down the path of defining a new clock that is
just a fork of the sdmmc_clk, so I just defined it as a gate-clock. I
think ultimately the gating of the sdmmc_clk is being done.

I can rename it to sdmmc_clk_divided.

Dinh

[PATCH] ARM: socfpga: dts: Add a ciu clock node for sdmmc

[Doug Anderson]

Hi,

On Fri, Apr 10, 2015 at 1:56 PM,  <dinguyen@opensource.altera.com> wrote:
> From: Dinh Nguyen <dinguyen@opensource.altera.com>
>
> The CIU(Card Interface Unit) clock is used by the dw_mmc IP to clock an SD
> card. The ciu_clk is the sdmmc_clk passed through a fixed divider of 4. This patch
> adds the ciu_clk node and makes the sdmmc_clk it's parent.
>
> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
> ---
>  arch/arm/boot/dts/socfpga.dtsi | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
> index d9176e6..25418ee 100644
> --- a/arch/arm/boot/dts/socfpga.dtsi
> +++ b/arch/arm/boot/dts/socfpga.dtsi
> @@ -451,6 +451,14 @@
>                                                 clk-phase = <0 135>;
>                                         };
>
> +                                       ciu_clk: ciu_clk {

Can't say I'm an expert on socfpga, but seems like this clock is only
for sdmmc, right?  ...so its name ought to have sdmmc in its name?

-Doug