[U-Boot] DWMMC crontroller in Exynos4412

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi Simon,
I'm working on implementing a driver for SD/MMC cards in the framework 
GenodeOS. I think you could help me with your experience in this type of 
implementation in the u-boot.
The hardware platform on which the driver will work is a ODROID-x2 
(exynos4412). I use the DWMMC contoller, but I'm not sure if this is the 
right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI 
controller is most appropriate?

Thank you for your help

[U-Boot] DWMMC crontroller in Exynos4412

[Simon Glass]

+Samsung people

Hi,

On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu> wrote:
> Hi Simon,
> I'm working on implementing a driver for SD/MMC cards in the framework
> GenodeOS. I think you could help me with your experience in this type of
> implementation in the u-boot.
> The hardware platform on which the driver will work is a ODROID-x2
> (exynos4412). I use the DWMMC contoller, but I'm not sure if this is the
> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
> controller is most appropriate?
>
> Thank you for your help

I'm not really sure - the compatible string for that node is:

compatible = "samsung,exynos4412-dw-mshc";

which is different from what exynos5 uses.

Possibly Lukasz / Przemyslaw know about this.

Regards,
Simon

[U-Boot] DWMMC crontroller in Exynos4412

[Jaehoon Chung]

On 08/26/2015 11:26 AM, Simon Glass wrote:
> +Samsung people
> 
> Hi,
> 
> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu> wrote:
>> Hi Simon,
>> I'm working on implementing a driver for SD/MMC cards in the framework
>> GenodeOS. I think you could help me with your experience in this type of
>> implementation in the u-boot.
>> The hardware platform on which the driver will work is a ODROID-x2
>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this is the
>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>> controller is most appropriate?

If you're using exynos4412 board, you can choose sdhci or dwmmc controller for eMMC, not SD/SDIO.
And in my experiment, dwmmc controller is more appropriate than sdhci.(ex, performance)

>>
>> Thank you for your help
> 
> I'm not really sure - the compatible string for that node is:
> 
> compatible = "samsung,exynos4412-dw-mshc";
> 
> which is different from what exynos5 uses.

As i know, Some register are difference..but i know it doesn't implemented for those registers at u-boot side.
If it should be implemented for upper mode than DDR50, it needs to check the compatible.

Best Regards,
Jaehoon Chung

> 
> Possibly Lukasz / Przemyslaw know about this.
> 
> Regards,
> Simon
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
> 

[U-Boot] DWMMC crontroller in Exynos4412

[Przemyslaw Marczak]

Hi,

On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
> On 08/26/2015 11:26 AM, Simon Glass wrote:
>> +Samsung people
>>
>> Hi,
>>
>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu> wrote:
>>> Hi Simon,
>>> I'm working on implementing a driver for SD/MMC cards in the framework
>>> GenodeOS. I think you could help me with your experience in this type of
>>> implementation in the u-boot.
>>> The hardware platform on which the driver will work is a ODROID-x2
>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this is the
>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>>> controller is most appropriate?
>
> If you're using exynos4412 board, you can choose sdhci or dwmmc controller for eMMC, not SD/SDIO.
> And in my experiment, dwmmc controller is more appropriate than sdhci.(ex, performance)
>

It depends which mmc channel is used. In Exynos4412, there are 5 
channels, but some channel configurations shares GPIO pins:
- MMC0 - sdhci
- MMC1 - sdhci, or MMC0 8-bit
- MMC2 - sdhci - Odroid SD card, 4-bit mode
- MMC3 - sdhci - or MMC2 8-bit
- MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode

Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).

So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is 
recommended for the better performance, but for SD card you must use 
sdhci controller.

Best regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com

>>>
>>> Thank you for your help
>>
>> I'm not really sure - the compatible string for that node is:
>>
>> compatible = "samsung,exynos4412-dw-mshc";
>>
>> which is different from what exynos5 uses.
>
> As i know, Some register are difference..but i know it doesn't implemented for those registers at u-boot side.
> If it should be implemented for upper mode than DDR50, it needs to check the compatible.
>
> Best Regards,
> Jaehoon Chung
>
>>
>> Possibly Lukasz / Przemyslaw know about this.
>>
>> Regards,
>> Simon
>> _______________________________________________
>> U-Boot mailing list
>> U-Boot at lists.denx.de
>> http://lists.denx.de/mailman/listinfo/u-boot
>>
>
>

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi community,

thank you all for answering my questions.

On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
> Hi,
>
> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>> +Samsung people
>>>
>>> Hi,
>>>
>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu> 
>>> wrote:
>>>> Hi Simon,
>>>> I'm working on implementing a driver for SD/MMC cards in the framework
>>>> GenodeOS. I think you could help me with your experience in this 
>>>> type of
>>>> implementation in the u-boot.
>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this 
>>>> is the
>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>>>> controller is most appropriate?
>>
>> If you're using exynos4412 board, you can choose sdhci or dwmmc 
>> controller for eMMC, not SD/SDIO.
>> And in my experiment, dwmmc controller is more appropriate than 
>> sdhci.(ex, performance)
>>
>
> It depends which mmc channel is used. In Exynos4412, there are 5 
> channels, but some channel configurations shares GPIO pins:
> - MMC0 - sdhci
> - MMC1 - sdhci, or MMC0 8-bit
> - MMC2 - sdhci - Odroid SD card, 4-bit mode
> - MMC3 - sdhci - or MMC2 8-bit
> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>
> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>
> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is 
> recommended for the better performance, but for SD card you must use 
> sdhci controller.
This information is valuable to me, but now I would help if you tell me 
where I can find the code of SDHCI controller for the SD card of 
Exynos4412 in U-boat 2015.04-rc2 for a implementationtation reference.  
I was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver, 
but now I have no idea what the file where the SDHCI driver for the 
exynos4412 is implemented.

Thank you very much for your collaboration.

[U-Boot] DWMMC crontroller in Exynos4412

[Przemyslaw Marczak]

Hi Humberto,

On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
> Hi community,
>
> thank you all for answering my questions.
>
> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>> Hi,
>>
>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>> +Samsung people
>>>>
>>>> Hi,
>>>>
>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu>
>>>> wrote:
>>>>> Hi Simon,
>>>>> I'm working on implementing a driver for SD/MMC cards in the framework
>>>>> GenodeOS. I think you could help me with your experience in this
>>>>> type of
>>>>> implementation in the u-boot.
>>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this
>>>>> is the
>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>>>>> controller is most appropriate?
>>>
>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>> controller for eMMC, not SD/SDIO.
>>> And in my experiment, dwmmc controller is more appropriate than
>>> sdhci.(ex, performance)
>>>
>>
>> It depends which mmc channel is used. In Exynos4412, there are 5
>> channels, but some channel configurations shares GPIO pins:
>> - MMC0 - sdhci
>> - MMC1 - sdhci, or MMC0 8-bit
>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>> - MMC3 - sdhci - or MMC2 8-bit
>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>
>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>
>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>> recommended for the better performance, but for SD card you must use
>> sdhci controller.
> This information is valuable to me, but now I would help if you tell me
> where I can find the code of SDHCI controller for the SD card of
> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation reference. I
> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver,
> but now I have no idea what the file where the SDHCI driver for the
> exynos4412 is implemented.
>
> Thank you very much for your collaboration.
>
>
>

Please check those files:
- drivers/mmc/s5p_sdhci.c
- drivers/mmc/sdhci.c

But, isn't the kernel a better reference for you?

Best regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi Przemyslaw,

On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
> Hi Humberto,
>
> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>> Hi community,
>>
>> thank you all for answering my questions.
>>
>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>> Hi,
>>>
>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>> +Samsung people
>>>>>
>>>>> Hi,
>>>>>
>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu>
>>>>> wrote:
>>>>>> Hi Simon,
>>>>>> I'm working on implementing a driver for SD/MMC cards in the 
>>>>>> framework
>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>> type of
>>>>>> implementation in the u-boot.
>>>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this
>>>>>> is the
>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>>>>>> controller is most appropriate?
>>>>
>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>> controller for eMMC, not SD/SDIO.
>>>> And in my experiment, dwmmc controller is more appropriate than
>>>> sdhci.(ex, performance)
>>>>
>>>
>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>> channels, but some channel configurations shares GPIO pins:
>>> - MMC0 - sdhci
>>> - MMC1 - sdhci, or MMC0 8-bit
>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>> - MMC3 - sdhci - or MMC2 8-bit
>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>
>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>
>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>> recommended for the better performance, but for SD card you must use
>>> sdhci controller.
>> This information is valuable to me, but now I would help if you tell me
>> where I can find the code of SDHCI controller for the SD card of
>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation reference. I
>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver,
>> but now I have no idea what the file where the SDHCI driver for the
>> exynos4412 is implemented.
>>
>> Thank you very much for your collaboration.
>>
>>
>>
>
> Please check those files:
> - drivers/mmc/s5p_sdhci.c
> - drivers/mmc/sdhci.c
>
> But, isn't the kernel a better reference for you?
Thanks for your time to answer my questions. I have reviewed the 
implementation of SDHCI controller in the Linux kernel for Odroid 
(https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not 
been able to identify the specific implementation that is used for 
handling of SD cards in exynos4412.
You know in what  file this controller is implemented? I think the file 
should be drivers/mmc/host/sdhci-s3c.c 
(https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c) 
but I'm not sure.
What do you think?

Thanks again.

Humberto

[U-Boot] DWMMC crontroller in Exynos4412

[Przemyslaw Marczak]

Hi Humberto,

On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
> Hi Przemyslaw,
>
> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>> Hi Humberto,
>>
>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>> Hi community,
>>>
>>> thank you all for answering my questions.
>>>
>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>> Hi,
>>>>
>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>> +Samsung people
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu>
>>>>>> wrote:
>>>>>>> Hi Simon,
>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>> framework
>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>> type of
>>>>>>> implementation in the u-boot.
>>>>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this
>>>>>>> is the
>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The SDHCI
>>>>>>> controller is most appropriate?
>>>>>
>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>> controller for eMMC, not SD/SDIO.
>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>> sdhci.(ex, performance)
>>>>>
>>>>
>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>> channels, but some channel configurations shares GPIO pins:
>>>> - MMC0 - sdhci
>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>
>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>
>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>> recommended for the better performance, but for SD card you must use
>>>> sdhci controller.
>>> This information is valuable to me, but now I would help if you tell me
>>> where I can find the code of SDHCI controller for the SD card of
>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation reference. I
>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver,
>>> but now I have no idea what the file where the SDHCI driver for the
>>> exynos4412 is implemented.
>>>
>>> Thank you very much for your collaboration.
>>>
>>>
>>>
>>
>> Please check those files:
>> - drivers/mmc/s5p_sdhci.c
>> - drivers/mmc/sdhci.c
>>
>> But, isn't the kernel a better reference for you?
> Thanks for your time to answer my questions. I have reviewed the
> implementation of SDHCI controller in the Linux kernel for Odroid
> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
> been able to identify the specific implementation that is used for
> handling of SD cards in exynos4412.
> You know in what  file this controller is implemented? I think the file
> should be drivers/mmc/host/sdhci-s3c.c
> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c)
> but I'm not sure.
> What do you think?
>
> Thanks again.
>
> Humberto
>

Yes, this is the right file. Also remember about the pinmux setting for 
sd/mmc.
In U-Boot: arch/arm/mach-exynos/pinmux.c
In kernel: drivers/pinctrl/pinctrl-exynos.c

Best regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi Przemyslaw,

With the information you gave me I managed to implement an important 
part of SDHCI controller. Currently the driver detects the SD card 
correctly but I have a problem with writing operations. With the help of 
linux command dd I found that the driver reads correctly but fails when 
trying to write. I studied implementations of SDHCI controller in the 
Linux kernel and the U-boot, but there are things I do not understand.

You have a document that explains how works the SDHCI controller ?

I've also been working on the implementation of DWMMC controller to 
manage the eMMC in ODROID-X2 (Exynos4412). Currently this driver detects 
the eMMC card but fails to calculate the capacity of the card. The read 
and write operations are not yet implemented.

You have a document that explains how works the DWMMC controller?

Thank you for your help!!
Humberto

On 08/27/2015 02:47 AM, Przemyslaw Marczak wrote:
> Hi Humberto,
>
> On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
>> Hi Przemyslaw,
>>
>> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>>> Hi Humberto,
>>>
>>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>>> Hi community,
>>>>
>>>> thank you all for answering my questions.
>>>>
>>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>>> Hi,
>>>>>
>>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>>> +Samsung people
>>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu>
>>>>>>> wrote:
>>>>>>>> Hi Simon,
>>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>>> framework
>>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>>> type of
>>>>>>>> implementation in the u-boot.
>>>>>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this
>>>>>>>> is the
>>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The 
>>>>>>>> SDHCI
>>>>>>>> controller is most appropriate?
>>>>>>
>>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>>> controller for eMMC, not SD/SDIO.
>>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>>> sdhci.(ex, performance)
>>>>>>
>>>>>
>>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>>> channels, but some channel configurations shares GPIO pins:
>>>>> - MMC0 - sdhci
>>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>>
>>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>>
>>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>>> recommended for the better performance, but for SD card you must use
>>>>> sdhci controller.
>>>> This information is valuable to me, but now I would help if you 
>>>> tell me
>>>> where I can find the code of SDHCI controller for the SD card of
>>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation 
>>>> reference. I
>>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver,
>>>> but now I have no idea what the file where the SDHCI driver for the
>>>> exynos4412 is implemented.
>>>>
>>>> Thank you very much for your collaboration.
>>>>
>>>>
>>>>
>>>
>>> Please check those files:
>>> - drivers/mmc/s5p_sdhci.c
>>> - drivers/mmc/sdhci.c
>>>
>>> But, isn't the kernel a better reference for you?
>> Thanks for your time to answer my questions. I have reviewed the
>> implementation of SDHCI controller in the Linux kernel for Odroid
>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
>> been able to identify the specific implementation that is used for
>> handling of SD cards in exynos4412.
>> You know in what  file this controller is implemented? I think the file
>> should be drivers/mmc/host/sdhci-s3c.c
>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c) 
>>
>> but I'm not sure.
>> What do you think?
>>
>> Thanks again.
>>
>> Humberto
>>
>
> Yes, this is the right file. Also remember about the pinmux setting 
> for sd/mmc.
> In U-Boot: arch/arm/mach-exynos/pinmux.c
> In kernel: drivers/pinctrl/pinctrl-exynos.c
>
> Best regards,

[U-Boot] DWMMC crontroller in Exynos4412

[Przemyslaw Marczak]

Hello Humberto,

On 09/28/2015 03:27 PM, Humberto L?pez Le?n wrote:
> Hi Przemyslaw,
>
> With the information you gave me I managed to implement an important
> part of SDHCI controller. Currently the driver detects the SD card
> correctly but I have a problem with writing operations. With the help of
> linux command dd I found that the driver reads correctly but fails when
> trying to write. I studied implementations of SDHCI controller in the
> Linux kernel and the U-boot, but there are things I do not understand.
>
> You have a document that explains how works the SDHCI controller ?

Please register at Jedec.org, and get this:

https://www.jedec.org/standards-documents/results/JESD84-B451

for eMMC 4.51, there are also older versions.

For SD card:

https://www.sdcard.org/downloads/pls/index.html

Try to find: SDCardStandardv1.9.pdf on the internet :)
>
> I've also been working on the implementation of DWMMC controller to
> manage the eMMC in ODROID-X2 (Exynos4412). Currently this driver detects
> the eMMC card but fails to calculate the capacity of the card. The read
> and write operations are not yet implemented.
>
> You have a document that explains how works the DWMMC controller?
>
> Thank you for your help!!
> Humberto
>

Which U-Boot version do you use? There was an issue in the mainline with 
device-tree, which results in eMMC/SD card detection issue.
I think, that in few days my patches with fixes can be merged.

> On 08/27/2015 02:47 AM, Przemyslaw Marczak wrote:
>> Hi Humberto,
>>
>> On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
>>> Hi Przemyslaw,
>>>
>>> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>>>> Hi Humberto,
>>>>
>>>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>>>> Hi community,
>>>>>
>>>>> thank you all for answering my questions.
>>>>>
>>>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>>>> Hi,
>>>>>>
>>>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>>>> +Samsung people
>>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n <humberto@uclv.cu>
>>>>>>>> wrote:
>>>>>>>>> Hi Simon,
>>>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>>>> framework
>>>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>>>> type of
>>>>>>>>> implementation in the u-boot.
>>>>>>>>> The hardware platform on which the driver will work is a ODROID-x2
>>>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if this
>>>>>>>>> is the
>>>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The
>>>>>>>>> SDHCI
>>>>>>>>> controller is most appropriate?
>>>>>>>
>>>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>>>> controller for eMMC, not SD/SDIO.
>>>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>>>> sdhci.(ex, performance)
>>>>>>>
>>>>>>
>>>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>>>> channels, but some channel configurations shares GPIO pins:
>>>>>> - MMC0 - sdhci
>>>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>>>
>>>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>>>
>>>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>>>> recommended for the better performance, but for SD card you must use
>>>>>> sdhci controller.
>>>>> This information is valuable to me, but now I would help if you
>>>>> tell me
>>>>> where I can find the code of SDHCI controller for the SD card of
>>>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation
>>>>> reference. I
>>>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC driver,
>>>>> but now I have no idea what the file where the SDHCI driver for the
>>>>> exynos4412 is implemented.
>>>>>
>>>>> Thank you very much for your collaboration.
>>>>>
>>>>>
>>>>>
>>>>
>>>> Please check those files:
>>>> - drivers/mmc/s5p_sdhci.c
>>>> - drivers/mmc/sdhci.c
>>>>
>>>> But, isn't the kernel a better reference for you?
>>> Thanks for your time to answer my questions. I have reviewed the
>>> implementation of SDHCI controller in the Linux kernel for Odroid
>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
>>> been able to identify the specific implementation that is used for
>>> handling of SD cards in exynos4412.
>>> You know in what  file this controller is implemented? I think the file
>>> should be drivers/mmc/host/sdhci-s3c.c
>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c)
>>>
>>> but I'm not sure.
>>> What do you think?
>>>
>>> Thanks again.
>>>
>>> Humberto
>>>
>>
>> Yes, this is the right file. Also remember about the pinmux setting
>> for sd/mmc.
>> In U-Boot: arch/arm/mach-exynos/pinmux.c
>> In kernel: drivers/pinctrl/pinctrl-exynos.c
>>
>> Best regards,
>
>

Best regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi Przemyslaw,

Thanks for the documents suggested by you. Now I understand better the 
SDHCI controller implementations. The U-boot version I'm using the 
downloaded from 
https://github.com/hardkernel/u-boot/commits/odroid-v2010.12. From where 
I can download the version you're fixing?

Thank you very much for your collaboration.
Humberto

On 10/01/2015 07:24 AM, Przemyslaw Marczak wrote:
> Hello Humberto,
>
> On 09/28/2015 03:27 PM, Humberto L?pez Le?n wrote:
>> Hi Przemyslaw,
>>
>> With the information you gave me I managed to implement an important
>> part of SDHCI controller. Currently the driver detects the SD card
>> correctly but I have a problem with writing operations. With the help of
>> linux command dd I found that the driver reads correctly but fails when
>> trying to write. I studied implementations of SDHCI controller in the
>> Linux kernel and the U-boot, but there are things I do not understand.
>>
>> You have a document that explains how works the SDHCI controller ?
>
> Please register at Jedec.org, and get this:
>
> https://www.jedec.org/standards-documents/results/JESD84-B451
>
> for eMMC 4.51, there are also older versions.
>
> For SD card:
>
> https://www.sdcard.org/downloads/pls/index.html
>
> Try to find: SDCardStandardv1.9.pdf on the internet :)
>>
>> I've also been working on the implementation of DWMMC controller to
>> manage the eMMC in ODROID-X2 (Exynos4412). Currently this driver detects
>> the eMMC card but fails to calculate the capacity of the card. The read
>> and write operations are not yet implemented.
>>
>> You have a document that explains how works the DWMMC controller?
>>
>> Thank you for your help!!
>> Humberto
>>
>
> Which U-Boot version do you use? There was an issue in the mainline 
> with device-tree, which results in eMMC/SD card detection issue.
> I think, that in few days my patches with fixes can be merged.
>> On 08/27/2015 02:47 AM, Przemyslaw Marczak wrote:
>>> Hi Humberto,
>>>
>>> On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
>>>> Hi Przemyslaw,
>>>>
>>>> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>>>>> Hi Humberto,
>>>>>
>>>>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>>>>> Hi community,
>>>>>>
>>>>>> thank you all for answering my questions.
>>>>>>
>>>>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>>>>> +Samsung people
>>>>>>>>>
>>>>>>>>> Hi,
>>>>>>>>>
>>>>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n 
>>>>>>>>> <humberto@uclv.cu>
>>>>>>>>> wrote:
>>>>>>>>>> Hi Simon,
>>>>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>>>>> framework
>>>>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>>>>> type of
>>>>>>>>>> implementation in the u-boot.
>>>>>>>>>> The hardware platform on which the driver will work is a 
>>>>>>>>>> ODROID-x2
>>>>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if 
>>>>>>>>>> this
>>>>>>>>>> is the
>>>>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The
>>>>>>>>>> SDHCI
>>>>>>>>>> controller is most appropriate?
>>>>>>>>
>>>>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>>>>> controller for eMMC, not SD/SDIO.
>>>>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>>>>> sdhci.(ex, performance)
>>>>>>>>
>>>>>>>
>>>>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>>>>> channels, but some channel configurations shares GPIO pins:
>>>>>>> - MMC0 - sdhci
>>>>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>>>>
>>>>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>>>>
>>>>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>>>>> recommended for the better performance, but for SD card you must 
>>>>>>> use
>>>>>>> sdhci controller.
>>>>>> This information is valuable to me, but now I would help if you
>>>>>> tell me
>>>>>> where I can find the code of SDHCI controller for the SD card of
>>>>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation
>>>>>> reference. I
>>>>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC 
>>>>>> driver,
>>>>>> but now I have no idea what the file where the SDHCI driver for the
>>>>>> exynos4412 is implemented.
>>>>>>
>>>>>> Thank you very much for your collaboration.
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>> Please check those files:
>>>>> - drivers/mmc/s5p_sdhci.c
>>>>> - drivers/mmc/sdhci.c
>>>>>
>>>>> But, isn't the kernel a better reference for you?
>>>> Thanks for your time to answer my questions. I have reviewed the
>>>> implementation of SDHCI controller in the Linux kernel for Odroid
>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
>>>> been able to identify the specific implementation that is used for
>>>> handling of SD cards in exynos4412.
>>>> You know in what  file this controller is implemented? I think the 
>>>> file
>>>> should be drivers/mmc/host/sdhci-s3c.c
>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c) 
>>>>
>>>>
>>>> but I'm not sure.
>>>> What do you think?
>>>>
>>>> Thanks again.
>>>>
>>>> Humberto
>>>>
>>>
>>> Yes, this is the right file. Also remember about the pinmux setting
>>> for sd/mmc.
>>> In U-Boot: arch/arm/mach-exynos/pinmux.c
>>> In kernel: drivers/pinctrl/pinctrl-exynos.c
>>>
>>> Best regards,
>>
>>
>
> Best regards,

[U-Boot] DWMMC crontroller in Exynos4412

[Humberto López León]

Hi Przemyslaw,

the version of the U-boot on which you made the corrections in the SDHCI 
controller is at 
https://github.com/hardkernel/u-boot/commits/odroid-v2015.10?

Regards,
Humberto

On 10/01/2015 07:24 AM, Przemyslaw Marczak wrote:
> Hello Humberto,
>
> On 09/28/2015 03:27 PM, Humberto L?pez Le?n wrote:
>> Hi Przemyslaw,
>>
>> With the information you gave me I managed to implement an important
>> part of SDHCI controller. Currently the driver detects the SD card
>> correctly but I have a problem with writing operations. With the help of
>> linux command dd I found that the driver reads correctly but fails when
>> trying to write. I studied implementations of SDHCI controller in the
>> Linux kernel and the U-boot, but there are things I do not understand.
>>
>> You have a document that explains how works the SDHCI controller ?
>
> Please register at Jedec.org, and get this:
>
> https://www.jedec.org/standards-documents/results/JESD84-B451
>
> for eMMC 4.51, there are also older versions.
>
> For SD card:
>
> https://www.sdcard.org/downloads/pls/index.html
>
> Try to find: SDCardStandardv1.9.pdf on the internet :)
>>
>> I've also been working on the implementation of DWMMC controller to
>> manage the eMMC in ODROID-X2 (Exynos4412). Currently this driver detects
>> the eMMC card but fails to calculate the capacity of the card. The read
>> and write operations are not yet implemented.
>>
>> You have a document that explains how works the DWMMC controller?
>>
>> Thank you for your help!!
>> Humberto
>>
>
> Which U-Boot version do you use? There was an issue in the mainline 
> with device-tree, which results in eMMC/SD card detection issue.
> I think, that in few days my patches with fixes can be merged.
>
>> On 08/27/2015 02:47 AM, Przemyslaw Marczak wrote:
>>> Hi Humberto,
>>>
>>> On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
>>>> Hi Przemyslaw,
>>>>
>>>> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>>>>> Hi Humberto,
>>>>>
>>>>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>>>>> Hi community,
>>>>>>
>>>>>> thank you all for answering my questions.
>>>>>>
>>>>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>>>>> +Samsung people
>>>>>>>>>
>>>>>>>>> Hi,
>>>>>>>>>
>>>>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n 
>>>>>>>>> <humberto@uclv.cu>
>>>>>>>>> wrote:
>>>>>>>>>> Hi Simon,
>>>>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>>>>> framework
>>>>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>>>>> type of
>>>>>>>>>> implementation in the u-boot.
>>>>>>>>>> The hardware platform on which the driver will work is a 
>>>>>>>>>> ODROID-x2
>>>>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if 
>>>>>>>>>> this
>>>>>>>>>> is the
>>>>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The
>>>>>>>>>> SDHCI
>>>>>>>>>> controller is most appropriate?
>>>>>>>>
>>>>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>>>>> controller for eMMC, not SD/SDIO.
>>>>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>>>>> sdhci.(ex, performance)
>>>>>>>>
>>>>>>>
>>>>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>>>>> channels, but some channel configurations shares GPIO pins:
>>>>>>> - MMC0 - sdhci
>>>>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>>>>
>>>>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>>>>
>>>>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>>>>> recommended for the better performance, but for SD card you must 
>>>>>>> use
>>>>>>> sdhci controller.
>>>>>> This information is valuable to me, but now I would help if you
>>>>>> tell me
>>>>>> where I can find the code of SDHCI controller for the SD card of
>>>>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation
>>>>>> reference. I
>>>>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC 
>>>>>> driver,
>>>>>> but now I have no idea what the file where the SDHCI driver for the
>>>>>> exynos4412 is implemented.
>>>>>>
>>>>>> Thank you very much for your collaboration.
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>> Please check those files:
>>>>> - drivers/mmc/s5p_sdhci.c
>>>>> - drivers/mmc/sdhci.c
>>>>>
>>>>> But, isn't the kernel a better reference for you?
>>>> Thanks for your time to answer my questions. I have reviewed the
>>>> implementation of SDHCI controller in the Linux kernel for Odroid
>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
>>>> been able to identify the specific implementation that is used for
>>>> handling of SD cards in exynos4412.
>>>> You know in what  file this controller is implemented? I think the 
>>>> file
>>>> should be drivers/mmc/host/sdhci-s3c.c
>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c) 
>>>>
>>>>
>>>> but I'm not sure.
>>>> What do you think?
>>>>
>>>> Thanks again.
>>>>
>>>> Humberto
>>>>
>>>
>>> Yes, this is the right file. Also remember about the pinmux setting
>>> for sd/mmc.
>>> In U-Boot: arch/arm/mach-exynos/pinmux.c
>>> In kernel: drivers/pinctrl/pinctrl-exynos.c
>>>
>>> Best regards,
>>
>>
>
> Best regards,

[U-Boot] DWMMC crontroller in Exynos4412

[Przemyslaw Marczak]

Hi Humberto,

On 10/07/2015 10:50 PM, Humberto L?pez Le?n wrote:
> Hi Przemyslaw,
>
> the version of the U-boot on which you made the corrections in the SDHCI
> controller is at
> https://github.com/hardkernel/u-boot/commits/odroid-v2015.10?
>
> Regards,
> Humberto
>

The U-Boot from your link is a Hardkernel's version, and it's very old.

Please check the mainline/master tree. On the top, there are few 
changes, which fixes the sdhci/mmc issue on Exynos. The problem was in 
device tree "reg" property parsing.

The mainline config for U3/X2 is "odroid_defconfig".

Best regards
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com


> On 10/01/2015 07:24 AM, Przemyslaw Marczak wrote:
>> Hello Humberto,
>>
>> On 09/28/2015 03:27 PM, Humberto L?pez Le?n wrote:
>>> Hi Przemyslaw,
>>>
>>> With the information you gave me I managed to implement an important
>>> part of SDHCI controller. Currently the driver detects the SD card
>>> correctly but I have a problem with writing operations. With the help of
>>> linux command dd I found that the driver reads correctly but fails when
>>> trying to write. I studied implementations of SDHCI controller in the
>>> Linux kernel and the U-boot, but there are things I do not understand.
>>>
>>> You have a document that explains how works the SDHCI controller ?
>>
>> Please register at Jedec.org, and get this:
>>
>> https://www.jedec.org/standards-documents/results/JESD84-B451
>>
>> for eMMC 4.51, there are also older versions.
>>
>> For SD card:
>>
>> https://www.sdcard.org/downloads/pls/index.html
>>
>> Try to find: SDCardStandardv1.9.pdf on the internet :)
>>>
>>> I've also been working on the implementation of DWMMC controller to
>>> manage the eMMC in ODROID-X2 (Exynos4412). Currently this driver detects
>>> the eMMC card but fails to calculate the capacity of the card. The read
>>> and write operations are not yet implemented.
>>>
>>> You have a document that explains how works the DWMMC controller?
>>>
>>> Thank you for your help!!
>>> Humberto
>>>
>>
>> Which U-Boot version do you use? There was an issue in the mainline
>> with device-tree, which results in eMMC/SD card detection issue.
>> I think, that in few days my patches with fixes can be merged.
>>
>>> On 08/27/2015 02:47 AM, Przemyslaw Marczak wrote:
>>>> Hi Humberto,
>>>>
>>>> On 08/26/2015 07:24 PM, Humberto L?pez Le?n wrote:
>>>>> Hi Przemyslaw,
>>>>>
>>>>> On 08/26/2015 10:12 AM, Przemyslaw Marczak wrote:
>>>>>> Hi Humberto,
>>>>>>
>>>>>> On 08/26/2015 03:40 PM, Humberto L?pez Le?n wrote:
>>>>>>> Hi community,
>>>>>>>
>>>>>>> thank you all for answering my questions.
>>>>>>>
>>>>>>> On 08/26/2015 02:53 AM, Przemyslaw Marczak wrote:
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> On 08/26/2015 08:23 AM, Jaehoon Chung wrote:
>>>>>>>>> On 08/26/2015 11:26 AM, Simon Glass wrote:
>>>>>>>>>> +Samsung people
>>>>>>>>>>
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> On 25 August 2015 at 13:10, Humberto L?pez Le?n
>>>>>>>>>> <humberto@uclv.cu>
>>>>>>>>>> wrote:
>>>>>>>>>>> Hi Simon,
>>>>>>>>>>> I'm working on implementing a driver for SD/MMC cards in the
>>>>>>>>>>> framework
>>>>>>>>>>> GenodeOS. I think you could help me with your experience in this
>>>>>>>>>>> type of
>>>>>>>>>>> implementation in the u-boot.
>>>>>>>>>>> The hardware platform on which the driver will work is a
>>>>>>>>>>> ODROID-x2
>>>>>>>>>>> (exynos4412). I use the DWMMC contoller, but I'm not sure if
>>>>>>>>>>> this
>>>>>>>>>>> is the
>>>>>>>>>>> right controller to handle SD/MMC cards in Exynos4412 SoC. The
>>>>>>>>>>> SDHCI
>>>>>>>>>>> controller is most appropriate?
>>>>>>>>>
>>>>>>>>> If you're using exynos4412 board, you can choose sdhci or dwmmc
>>>>>>>>> controller for eMMC, not SD/SDIO.
>>>>>>>>> And in my experiment, dwmmc controller is more appropriate than
>>>>>>>>> sdhci.(ex, performance)
>>>>>>>>>
>>>>>>>>
>>>>>>>> It depends which mmc channel is used. In Exynos4412, there are 5
>>>>>>>> channels, but some channel configurations shares GPIO pins:
>>>>>>>> - MMC0 - sdhci
>>>>>>>> - MMC1 - sdhci, or MMC0 8-bit
>>>>>>>> - MMC2 - sdhci - Odroid SD card, 4-bit mode
>>>>>>>> - MMC3 - sdhci - or MMC2 8-bit
>>>>>>>> - MMC4 - dwmmc, uses MMC0 pins for 4-bit, and MMC0-1 for 8-bit mode
>>>>>>>>
>>>>>>>> Odroid is using MMC2(sdhci) and MMC0/4(sdhci or dwmmc).
>>>>>>>>
>>>>>>>> So for eMMC cards you can use the dwmmc, and as Jaehoon wrote it is
>>>>>>>> recommended for the better performance, but for SD card you must
>>>>>>>> use
>>>>>>>> sdhci controller.
>>>>>>> This information is valuable to me, but now I would help if you
>>>>>>> tell me
>>>>>>> where I can find the code of SDHCI controller for the SD card of
>>>>>>> Exynos4412 in U-boat 2015.04-rc2 for a implementationtation
>>>>>>> reference. I
>>>>>>> was reviewing the file  exynos_dw_mmc.c as reference of DWMMC
>>>>>>> driver,
>>>>>>> but now I have no idea what the file where the SDHCI driver for the
>>>>>>> exynos4412 is implemented.
>>>>>>>
>>>>>>> Thank you very much for your collaboration.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> Please check those files:
>>>>>> - drivers/mmc/s5p_sdhci.c
>>>>>> - drivers/mmc/sdhci.c
>>>>>>
>>>>>> But, isn't the kernel a better reference for you?
>>>>> Thanks for your time to answer my questions. I have reviewed the
>>>>> implementation of SDHCI controller in the Linux kernel for Odroid
>>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/), but have not
>>>>> been able to identify the specific implementation that is used for
>>>>> handling of SD cards in exynos4412.
>>>>> You know in what  file this controller is implemented? I think the
>>>>> file
>>>>> should be drivers/mmc/host/sdhci-s3c.c
>>>>> (https://github.com/hardkernel/linux/blob/odroid-3.0.y/drivers/mmc/host/sdhci-s3c.c)
>>>>>
>>>>>
>>>>> but I'm not sure.
>>>>> What do you think?
>>>>>
>>>>> Thanks again.
>>>>>
>>>>> Humberto
>>>>>
>>>>
>>>> Yes, this is the right file. Also remember about the pinmux setting
>>>> for sd/mmc.
>>>> In U-Boot: arch/arm/mach-exynos/pinmux.c
>>>> In kernel: drivers/pinctrl/pinctrl-exynos.c
>>>>
>>>> Best regards,
>>>
>>>
>>
>> Best regards,
>
>