[PATCH 3/3] ARM: dts: EMIF and LPDDR2 device tree data for OMAP5 boards

Lokesh Vutla lokeshvutla at ti.com
Thu Oct 11 02:16:42 EDT 2012


+ devicetree-discuss

Hi Benoit,

On Wednesday 10 October 2012 08:31 PM, Benoit Cousson wrote:
> On 10/10/2012 02:05 PM, Lokesh Vutla wrote:
>> Device tree data for the EMIF sdram controllers in OMAP5
>> and LPDDR2 memory devices attached to OMAP5 boards.
>
> Nit: Could you make a sentence with a verb to explain what you are doing
> in this patch.
I am really sorry about this.
I ll make sure that all patch descriptions will be clear in V2 of this 
patch series.

In this patch I am adding device tree data for LPDDR2 memory devices 
attached to omap5-sevm and also adding device tree data for EMIF sdram 
controllers in OMAP5.
>
>> Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
>> ---
>>   arch/arm/boot/dts/lpddr2_data.dtsi |   64 +++++++++++++++++++++++++++++++++++-
>>   arch/arm/boot/dts/omap5-evm.dts    |   11 +++++++
>>   arch/arm/boot/dts/omap5.dtsi       |   18 ++++++++++
>>   3 files changed, 92 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm/boot/dts/lpddr2_data.dtsi b/arch/arm/boot/dts/lpddr2_data.dtsi
>> index f97f70f..8e8c1bc 100644
>> --- a/arch/arm/boot/dts/lpddr2_data.dtsi
>> +++ b/arch/arm/boot/dts/lpddr2_data.dtsi
>> @@ -3,7 +3,7 @@
>>    */
>>
>>   / {
>> -	elpida_ECB240ABACN: lpddr2 {
>> +	elpida_ECB240ABACN: lpddr2 at 0 {
>>   		compatible	= "Elpida,ECB240ABACN","jedec,lpddr2-s4";
>>   		density		= <2048>;
>>   		io-width	= <32>;
>> @@ -64,4 +64,66 @@
>>   			tDQSCK-max-derated = <6000>;
>>   		};
>>   	};
>> +
>> +	samsung_K3PE0E000B: lpddr2 at 1 {
>
> I'm confused now, why are you reusing the same lpddr2_data.dtsi file?
> You should create a file per memory. That will make the reuse much easier.
>
> If the goal of your first patch was to do that, it is then the wrong
> approach.
Yes, I wanted to group data for all lppdr2 devices in a single file than 
creating separate file for each device.
May be a dumb question, Why can't we group data for all the lpddr2 
devices in a single file?
>
>> +		compatible	= "Samsung,K3PE0E000B","jedec,lpddr2-s4";
>> +		density		= <4096>;
>> +		io-width	= <32>;
>> +
>> +		tRPab-min-tck	= <3>;
>> +		tRCD-min-tck	= <3>;
>> +		tWR-min-tck	= <3>;
>> +		tRASmin-min-tck	= <3>;
>> +		tRRD-min-tck	= <2>;
>> +		tWTR-min-tck	= <2>;
>> +		tXP-min-tck	= <2>;
>> +		tRTP-min-tck	= <2>;
>> +		tCKE-min-tck	= <3>;
>> +		tCKESR-min-tck	= <3>;
>> +		tFAW-min-tck	= <8>;
>> +
>> +		timings_samsung_K3PE0E000B_533mhz: lpddr2-timings at 0 {
>> +			compatible	= "jedec,lpddr2-timings";
>> +			min-freq	= <10000000>;
>> +			max-freq	= <533333333>;
>> +			tRPab		= <21000>;
>> +			tRCD		= <18000>;
>> +			tWR		= <15000>;
>> +			tRAS-min	= <42000>;
>> +			tRRD		= <10000>;
>> +			tWTR		= <7500>;
>> +			tXP		= <7500>;
>> +			tRTP		= <7500>;
>> +			tCKESR		= <15000>;
>> +			tDQSCK-max	= <5500>;
>> +			tFAW		= <50000>;
>> +			tZQCS		= <90000>;
>> +			tZQCL		= <360000>;
>> +			tZQinit		= <1000000>;
>> +			tRAS-max-ns	= <70000>;
>> +			tDQSCK-max-derated = <5620>;
>> +		};
>> +
>> +		timings_samsung_K3PE0E000B_266mhz: lpddr2-timings at 1 {
>> +			compatible	= "jedec,lpddr2-timings";
>> +			min-freq	= <10000000>;
>> +			max-freq	= <266666666>;
>> +			tRPab		= <21000>;
>> +			tRCD		= <18000>;
>> +			tWR		= <15000>;
>> +			tRAS-min	= <42000>;
>> +			tRRD		= <10000>;
>> +			tWTR		= <7500>;
>> +			tXP		= <7500>;
>> +			tRTP		= <7500>;
>> +			tCKESR		= <15000>;
>> +			tDQSCK-max	= <5500>;
>> +			tFAW		= <50000>;
>> +			tZQCS		= <90000>;
>> +			tZQCL		= <360000>;
>> +			tZQinit		= <1000000>;
>> +			tRAS-max-ns	= <70000>;
>> +			tDQSCK-max-derated = <6000>;
>> +		};
>> +	};
>>   };
>> diff --git a/arch/arm/boot/dts/omap5-evm.dts b/arch/arm/boot/dts/omap5-evm.dts
>> index 6f87e1a..8a952f8 100644
>> --- a/arch/arm/boot/dts/omap5-evm.dts
>> +++ b/arch/arm/boot/dts/omap5-evm.dts
>> @@ -8,6 +8,7 @@
>>   /dts-v1/;
>>
>>   /include/ "omap5.dtsi"
>> +/include/ "lpddr2_data.dtsi"
>>
>>   / {
>>   	model = "TI OMAP5 EVM board";
>> @@ -82,3 +83,13 @@
>>   			0x020700d9>;	/* SEARCH */
>>   	linux,input-no-autorepeat;
>>   };
>> +
>> +&emif1 {
>> +	cs1-used;
>> +	device-handle = <&samsung_K3PE0E000B>;
>> +};
>> +
>> +&emif2 {
>> +	cs1-used;
>> +	device-handle = <&samsung_K3PE0E000B>;
>> +};
>> diff --git a/arch/arm/boot/dts/omap5.dtsi b/arch/arm/boot/dts/omap5.dtsi
>> index 5db33f4..40b41c2 100644
>> --- a/arch/arm/boot/dts/omap5.dtsi
>> +++ b/arch/arm/boot/dts/omap5.dtsi
>> @@ -319,5 +319,23 @@
>>   			ti,buffer-size = <128>;
>>   			ti,hwmods = "mcbsp3";
>>   		};
>> +
>> +		emif1: emif at 0x4c000000 {
>> +			compatible	= "ti,emif-4d5";
>> +			ti,hwmods	= "emif1";
>> +			phy-type	= <2>;
>> +			hw-caps-read-idle-ctrl;
>> +			hw-caps-ll-interface;
>> +			hw-caps-temp-alert;
>
> You should now add the reg, and interrupt attributes as well.
OK I ll add these fields.

Thanks,
Lokesh
>
> Regards,
> Benoit
>




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