Fail to reset on Odroid-C4

[Neil Armstrong]

Hi,

On 06/11/2020 03:10, Jaehoon Chung wrote:
> Hi,
> 
> I have checked U-boot on Odroid-C4 with v2020.10.
> I found a problem about reset behavior.
> 
> In my environment,
> - Boot to SD-card,
> - built u-boot v2020.10 with ordoid-c4_defconfig
> - Referred to doc/board/amlogic/odroid-c4.rst
> 
> 
> If do "reset" command after run command "mmcinfo", it didn't work anymore.
> - After something to do operation relevant to MMC. (read/write or ls mmc, etc..)
> 
> 
> U-Boot 2020.10-00383-g2f27fb20151b-dirty (Nov 06 2020 - 10:37:09 +0900) odroid-c4
> 
> Model: Hardkernel ODROID-C4
> SoC:   Amlogic Meson SM1 (Unknown) Revision 2b:c (10:2)
> DRAM:  3.8 GiB
> MMC:   sd at ffe05000: 0, mmc at ffe07000: 1
> In:    serial
> Out:   serial
> Err:   serial
> Net:   eth0: ethernet at ff3f0000
> Hit any key to stop autoboot:  0
> Odroid N2>
> Odroid N2>
> Odroid N2>
> Odroid N2>
> Odroid N2>
> Odroid N2> mmcinfo
> Device: sd at ffe05000
> Manufacturer ID: 3
> OEM: 5344
> Name: SB16G
> Bus Speed: 50000000
> Mode: SD High Speed (50MHz)
> Rd Block Len: 512
> SD version 3.0
> High Capacity: Yes
> Capacity: 14.8 GiB
> Bus Width: 4-bit
> Erase Group Size: 512 Bytes
> Odroid N2> reset
> resetting ...
> bl31 reboot reason: 0xd
> bl31 reboot reason: 0x0
> system cmd  1.
> SM1:BL:511f6b:81ca2f;FEAT:A0F83180:20282000;POC:F;RCY:0;EMMC:800;NAND:81;SD?:0;SD:0;READ:0;0.0;CHK:0;
> bl2_stage_init 0x01
> bl2_stage_init 0x81
> hw id:?M1:BL:511f6b:81ca2f;FEAT:A0F83180:20282000;POC:F;RCY:0;EMMC:800;NAND:81;SD?:0;SD:800;USB:8;

It's a new one !

> 
> 
> I didn't analyze it in more detail. I will do. But it seems that relevant to BL2 binary.
> If nothing to do before reset, it's working fine.

Is this the same with SDCard ?

The SDCard & eMMC regulators doesn't reset to default when resetting, causing issues
with the boot ROM... maybe you'll need to reset the regulators in a reset for the
Odroid C4 board.

> 
> If someone already fixed this or I missed something to do, let me know, plz.

AFAIK no, I just pushed a fix for the eMMC/SDCard clock causing read issues at 50MHz.

Thanks for the patches & reports !

Neil

> 
> Best Regards,
> Jaehoon Chung
>