[PATCH 0/3] rockchip: sdhci: Add HS400 Enhanced Strobe support

[Jack Mitchell]

On 02/11/2021 08:02, Peter Robinson wrote:
> On Mon, Nov 1, 2021 at 10:32 PM Jack Mitchell <ml at embed.me.uk> wrote:
>>
>> On 01/11/2021 22:11, Peter Robinson wrote:
>>> On Mon, Nov 1, 2021 at 11:18 AM Jack Mitchell <ml at embed.me.uk> wrote:
>>>>
>>>> On 01/11/2021 09:07, Alper Nebi Yasak wrote:
>>>>> I'm trying to make my gru-kevin's eMMC work properly (it times out while
>>>>> tuning for HS400 and stops working when reinitialized via "mmc dev 0").
>>>>
>>>> I'm also experiencing issue with the re-init of emmc on a 3399 platform,
>>>> did you come to any conclusions on the reason? It works fine to load
>>>> u-boot proper from SPL but then fails in u-boot proper when attempting
>>>> to perform any mmc activity.
>>>
>>> Does the following patch fix the rk3399 problem?
>>> http://patchwork.ozlabs.org/project/uboot/patch/20211101044347.17822-1-yifeng.zhao@rock-chips.com/
>>>
>>
>> Hi Peter,
>>
>> I have this patch in my tree which fixes the initial init of the emmc,
>> but it then fails later when it is re-initialised. Does everything work
>> fine on your Rock960, can you boot Linux from the emmc when going SPL
>> (emmc) -> Proper (emmc) -> Linux (emmc)?
> 
> Yes, I tested it last night with the patch applied on 2021.10.

If you get some time would you mind checking what speed the emmc is
running at, by breaking into u-boot proper and running `mmc info`. I'm
wondering if yours isn't configuring at hs400 and therefore bypassing
the issue.

> 
>> Thanks for the suggestion!
>>
>> Regards,
>>
>>>> Regards,
>>>> Jack.
>>>>
>>>>> While experimenting with what works on my board I ended up implementing
>>>>> HS400ES support. And while I'm at it, I decided to do it for RK3568 as
>>>>> well since it turned out easy enough. Both are ported from relevant
>>>>> Linux drivers.
>>>>>
>>>>> I'm trying this with "load mmc 0:1 0xd0000000 /bigfile $size" and getting
>>>>> the following speeds; and with "mmc info" the following differences:
>>>>>
>>>>>     gru-kevin mmc0      | w/o this series           | w/ this series
>>>>>     --------------------+---------------------------+-------------------
>>>>>     Bus Speed           | 52000000                  | 200000000
>>>>>     Mode                | MMC High Speed (52MHz)    | HS400ES (200 MHz)
>>>>>     8MiB Load Speed     | ~9.5 MiB/s                | ~51.5 MiB/s
>>>>>     256MiB Load Speed   | ~177.8 MiB/s              | ~114.5 MiB/s
>>>>>
>>>>> Listing partitions, listing files, reading files and the loaded bytes
>>>>> all look fine to me, but I'm not sure I haven't missed anything.
>>>>>
>>>>>
>>>>> Alper Nebi Yasak (3):
>>>>>   mmc: sdhci: Add HS400 Enhanced Strobe support
>>>>>   rockchip: sdhci: Add HS400 Enhanced Strobe support for RK3399
>>>>>   rockchip: sdhci: Add HS400 Enhanced Strobe support for RK3568
>>>>>
>>>>>  drivers/mmc/rockchip_sdhci.c | 51 ++++++++++++++++++++++++++++++++++++
>>>>>  drivers/mmc/sdhci.c          | 18 +++++++++++++
>>>>>  include/sdhci.h              |  1 +
>>>>>  3 files changed, 70 insertions(+)
>>>>>
>>>>
>>>> --
>>>> Jack Mitchell, Consultant
>>>> https://www.tuxable.co.uk
>>
>>
>> --
>> Jack Mitchell, Consultant
>> https://www.tuxable.co.uk


-- 
Jack Mitchell, Consultant
https://www.tuxable.co.uk