Help with u-boot when using the eMMC card in DDR mode

[Jaehoon Chung]

On 7/26/21 5:36 PM, Abder wrote:
> Hi Jaehoon,
> This is the output with MMC_TRACE enabled
> 
> U-Boot >mmc dev 2
> blk_find_device: if_type=6, devnum=2: usdhc at 02198000.blk, 6, 2
> ofnode_read_u32: vmmc-supply: 0x33 (51)
> ofnode_read_u32: vqmmc-supply: 0x33 (51)
> clock is disabled (0Hz)
> fixed_regulator_set_enable: dev='3p3v', enable=1, delay=0, has_gpio=0
> clock is enabled (400000Hz)
> CMD_SEND:0
>                 ARG                      0x00000000
>                 MMC_RSP_NONE
> CMD_SEND:8
>                 ARG                      0x000001aa
>                 RET                      -110
> CMD_SEND:55
>                 ARG                      0x00000000
>                 RET                      -110
> CMD_SEND:0
>                 ARG                      0x00000000
>                 MMC_RSP_NONE
> CMD_SEND:1
>                 ARG                      0x00000000
>                 MMC_RSP_R3,4             0x00ff8080
> CMD_SEND:1
>                 ARG                      0x40300000
>                 MMC_RSP_R3,4             0x00ff8080
> CMD_SEND:0
>                 ARG                      0x00000000
>                 MMC_RSP_NONE
> CMD_SEND:1
>                 ARG                      0x40300000
>                 MMC_RSP_R3,4             0x00ff8080
> CMD_SEND:1
>                 ARG                      0x40300000
>                 MMC_RSP_R3,4             0x00ff8080
> CMD_SEND:1
>                 ARG                      0x40300000
>                 MMC_RSP_R3,4             0x00ff8080
> CMD_SEND:1
>                 ARG                      0x40300000
>                 MMC_RSP_R3,4             0xc0ff8080
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> CMD_SEND:2
>                 ARG                      0x00000000
>                 RET                      -70
> Command failed, result=1
> U-Boot >
> 
> I believe the -70 error is an ECOM error  (Communication error on send).
> However this does not occur when eMMC is in HS mode for example.
> and even in DDR mode, before executing the "mmc dev 2" cmd, the
> communication with the emmc with "load" works without a hitch.

Sorry. I didn't understand clearly. 
Does DDR mode work fine before "mmc dev 2" command?
Did you try to run other command? e,g) mmcinfo or mmc rescan?

It seems that error is returned in fsl_esdhc_imx.c.
Well, it seems that not cleared something after some operation.
It needs to check full log and sequence.

Best Regards,
Jaehoon Chung

> 
> 
> 
> Le lun. 26 juil. 2021 à 10:03, Jaehoon Chung <jh80.chung at samsung.com> a
> écrit :
> 
>> Hi,
>>
>> On 7/26/21 4:41 PM, Abder wrote:
>>> Hi,
>>>
>>> I have been trying recently to optimize the boot time on a customized
>> board
>>> based on the IMX6DP.
>>>
>>> For the time being, I succeeded in enabling the DDR (dual data rate) mode
>>> for the emmc to speed up the data rate for read and write cycles in
>> u-boot.
>>>
>>> By reading a file from the emmc using the "load" command (e.g. load mmc
>> 2:1
>>> 0x12000000 file), I can see that the data rate has doubled, confirming
>> that
>>> the DDR mode is enabled.
>>>
>>> However, the problem I have is that when I execute the u-boot command
>> "mmc
>>> dev 2" to switch the current device to the onboard eMMC, the command
>> fails
>>> with the output below : (with DEBUG enabled)
>>
>> If you can enable CONFIG_MMC_TRACE, then you can get more information
>> relevant to MMC.
>> Could you also share log after enabled MMC_TRACE?
>>
>> Best Regards,
>> Jaehoon Chung
>>
>>>
>>> U-Boot >mmc dev 2
>>> blk_find_device: if_type=6, devnum=2: usdhc at 02198000.blk, 6, 2
>>> ofnode_read_u32: vmmc-supply: 0x33 (51)
>>> ofnode_read_u32: vqmmc-supply: 0x33 (51)
>>> clock is disabled (0Hz)
>>> fixed_regulator_set_enable: dev='3p3v', enable=1, delay=0, has_gpio=0
>>> clock is enabled (400000Hz)
>>> Command failed, result=1
>>> U-Boot >
>>>
>>> and after this command, any attempt to interact with the emmc (e.g. fatls
>>> mmc 2:1 ) ends with failure.
>>>
>>> To enable the DDR mode, all I did was define the macro
>>> CONFIG_SYS_FSL_ESDHC_HAS_DDR_MODE in the header of my board.
>>>
>>> Any help is greatly appreciated !
>>>
>>> --
>>>
>>> Abder,
>>>
>>
>>
>