[PATCH 3/3] ARM: dts: exynos5422-odroidxu3: Added UHS-I bus speed support
Jaehoon Chung
jh80.chung at samsung.com
Wed Oct 21 03:28:54 PDT 2015
Hi, Anand.
On 10/14/2015 12:58 PM, Anand Moon wrote:
> hi Krzysztof,
>
> On 14 October 2015 at 05:29, Krzysztof Kozlowski
> <k.kozlowski at samsung.com> wrote:
>> On 14.10.2015 01:27, Anand Moon wrote:
>>> Hi Krzysztof,
>>>
>>> On 13 October 2015 at 09:13, Krzysztof Kozlowski
>>> <k.kozlowski at samsung.com> wrote:
>>>>
>>>> On 13.10.2015 12:08, Anand Moon wrote:
>>>>> Hi Krzysztof,
>>>>>
>>>>> On 13 October 2015 at 05:44, Krzysztof Kozlowski
>>>>> <k.kozlowski at samsung.com> wrote:
>>>>>> On 13.10.2015 00:32, Anand Moon wrote:
>>>>>>> Hi Krzysztof,
>>>>>>>
>>>>>>> On 12 October 2015 at 11:14, Krzysztof Kozlowski
>>>>>>> <k.kozlowski at samsung.com> wrote:
>>>>>>>> On 12.10.2015 00:46, Anand Moon wrote:
>>>>>>>>> Added support for UHS-I bus speed 50MB/s (SDR50, DDR50) 104MB/s (SDR104)
>>>>>>>>
>>>>>>>> This description is not entirely correct. The MMC driver already
>>>>>>>> supports these UHS speeds (you did not any code) so you rather enabled
>>>>>>>> it (description of bindings says "is supported").
>>>>>>>>
>>>>>>>> You mentioned DDR50 but I don't see respective property below.
>>>>>>>>
>>>>>>>> How do you know that these modes are really supported? I don't know. Can
>>>>>>>> you convince me?
>>>>>>>
>>>>>>> Setting this DDR50 capability give me this error. That's the reason to
>>>>>>> drop this capability.
>>>>>>
>>>>>> But you mentioned it in commit message! "Added support for UHS-I ...
>>>>>> (DDR50)"
>>>>>>
>>>>>> In the same time dropping DDR50 is not an sufficient proof that "SDR50
>>>>>> and SDR104 are really supported".
>>>>>>
>>>>>
>>>>> These changes are related to the microSD card capabilities.
>>>>> So SDR50 have better frequency over DDR50. On the same Sandisk card.
>>>>>
>>>>> When the card select the capability for DDR50
>>>>> ---------------------------------------------------
>>>>> [ 4.001477] mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot
>>>>> req 50000000Hz, actual 50000000HZ div = 0)
>>>>> [ 4.001604] mmc1: new ultra high speed DDR50 SDHC card at address aaaa
>>>>> [ 4.004505] mmcblk0: mmc1:aaaa SL32G 29.7 GiB
>>>>> [ 4.009179] mmcblk0: error -110 sending status command, retrying
>>>>> [ 4.009271] mmcblk0: error -115 sending stop command, original cmd
>>>>> response 0x900, card status 0x900
>>>>> [ 4.009275] mmcblk0: error -84 transferring data, sector 0, nr 8,
>>>>> cmd response 0x900, card status 0x0
>>>>> [ 4.025563] mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot
>>>>> req 400000Hz, actual 396825HZ div = 63)
>>>>> [ 4.067770] Console: switching to colour frame buffer device 274x77
>>>>> [ 4.098782] mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot
>>>>> req 50000000Hz, actual 50000000HZ div = 0)
>>>>> [ 4.099692] mmc1: tried to reset card
>>>>> [ 4.101332] mmcblk0: p1 p2
I found this issue that produced on your board.
I will send the patch and test DDR50 on your board.
Best Regards,
Jaehoon Chung
>>>>>
>>>>>
>>>>> When the card select the capability for SDR50
>>>>> ---------------------------------------------------------------------------------
>>>>> [ 2.439806] mmc_host mmc1: Bus speed (slot 0) = 100000000Hz (slot req
>>>>> 100000000Hz, actual 100000000HZ div = 0)
>>>>> [ 2.449729] mmc1: new ultra high speed SDR50 SDHC card at address aaaa
>>>>> [ 2.455984] mmcblk0: mmc1:aaaa SL32G 29.7 GiB
>>>>> [ 2.461743] mmcblk0: p1 p2
>>>>>
>>>>> Which will relate to better read/write speed.
>>>>
>>>> Which is not an answer to my question. To none of my previous questions.
>>>>
>>>
>>> Basically UHS-I capability (sd-uhs-sdr12, sd-uhs-sdr25, sd-uhs-sdr50,
>>> sd-uhs-sdr104) help tune speed supported for mmc
>>>
>>> I have tired to compare the speed on high speed UHS-I vs ultra high
>>> speed UHS-I using izone utility.
>>>
>>> [ 2.572469] mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot
>>> req 50000000Hz, actual 50000000HZ div = 0)
>>> [ 2.572609] mmc1: new high speed SDHC card at address aaaa
>>>
>>> Command line used: ./iozone -L64 -S32 -azecwI -+n -r4k -r64k
>>> -r128k -s10M -i0 -i1 -i2 -f datafile -Rb out.xls
>>> Output is in kBytes/sec
>>> Time Resolution = 0.000001 seconds.
>>> Processor cache size set to 32 kBytes.
>>> Processor cache line size set to 64 bytes.
>>> File stride size set to 17 * record size.
>>> random
>>> random bkwd record stride
>>> kB reclen write rewrite read reread read
>>> write read rewrite read fwrite frewrite fread
>>> freread
>>> 10240 4 1631 0 6556 0 5538 982
>>> 10240 64 8828 0 18897 0 17994 303
>>> 10240 128 6269 0 20670 0 20128 1096
>>> ---------------------------------------------------------------------------------------------------------
>>> [ 2.613761] mmc_host mmc1: Bus speed (slot 0) = 100000000Hz (slot
>>> req 100000000Hz, actual 100000000HZ div = 0)
>>> [ 2.623573] mmc1: new ultra high speed SDR50 SDHC card at address aaaa
>>>
>>> Command line used: ./iozone -L64 -S32 -azecwI -+n -r4k -r64k
>>> -r128k -s10M -i0 -i1 -i2 -f datafile -Rb out.xls
>>> Output is in kBytes/sec
>>> Time Resolution = 0.000001 seconds.
>>> Processor cache size set to 32 kBytes.
>>> Processor cache line size set to 64 bytes.
>>> File stride size set to 17 * record size.
>>> random
>>> random bkwd record stride
>>> kB reclen write rewrite read reread read
>>> write read rewrite read fwrite frewrite fread
>>> freread
>>> 10240 4 1809 0 7507 0 5233 859
>>> 10240 64 11622 0 31250 0 28072 516
>>> 10240 128 4320 0 34417 0 32509 1148
>>>
>>> My observation is that their slight increase in read/write operation.
>>>
>>> Hope I have tried to answer you query. If I am wrong please let me know.
>>
>> Nope, that did not answer my query. You gave some performance benchmarks
>> but my question was not about the speed of anything. The question is
>> (once again):
>> How do you know that these modes are really supported?
>>
>> You are marking the *host* as supporting these modes. Please provide
>> information that host supports them *really*, not by experimenting "oh,
>> it seems to work now, maybe it will work always".
>>
>> Usually vendors, if their products implement some kind of
>> specification/protocol, they mark the products as "compatible with XYZ" etc.
>
> I found this link from hardkernel website which specify the interface support
>
> http://www.hardkernel.com/main/products/prdt_info.php?g_code=G141578491347
>
> Manufacturer Part Number : Sandisk SDSDQAD-016G
> Interface : UHS-1 SDR50
>
> I don't know much internal specification of the Odroid XU3/XU4 Boards.
>
> I am not sure if it will support host will sd-uhs-sdr104, but it will
> be compatible for sd-uhs-sdr12, sd-uhs-sdr25, sd-uhs-sdr50.
>
> -Anand Moon
>
>>
>> Best regards,
>> Krzysztof
>
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