[PATCH 1/1] pinephone_defconfig: lower DRAM clock to 528

[Bob]

On 2/28/21 8:25 AM, André Przywara wrote:
> On 22/02/2021 22:11, Bob wrote:
>
> Hi Bob,

Hello André,

Thanks for reaching out.

>> Lower DRAM clock speed to the official speed for the pinephone design: 528
> Can you elaborate why this is necessary? Are there reports with the
> existing data rate causing problems?
>
> Please keep in mind that the whole DRAM timings we use do not confirm to
> any JEDEC standards, mostly the parameters are derived from some
> Allwinner provided data. Since the clock frequency is connected to the
> timing parameters (many values are defined in terms of number of
> cycles), just lowering the frequency can have any kind of effects.

Sure, here is a quick resume of the issue logged at postmarketOS 
(https://gitlab.com/postmarketOS/pmaports/-/issues/981)

I own many pinephone and one of them, in the recent KDE batch, had 
random crashes.

After reaching out to the pmOS team, Oliver Smith and Martijn Braam 
asked me to test with the clock set at 528.

This solved the problem right away. Martijn also confirmed the official 
speed for the pinephone design is 528.

Let me know if you need addition info.

>> Signed-off-by: Bobby The Builder <bob at najdan.com>
> Since this is a legal statement, I am afraid it has to carry your real name.

Would you mind sharing a link related to this legal requirement ? I'd 
like to understand my legal obligations related to this patch proposal.

Once I understand it better, what's the suggested way to update this 
patch request ?

Best regards,

Bob.

>
> Cheers,
> Andre
>
>> ---
>>   configs/pinephone_defconfig | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/configs/pinephone_defconfig b/configs/pinephone_defconfig
>> index d8ee930a69..702e2bdc14 100644
>> --- a/configs/pinephone_defconfig
>> +++ b/configs/pinephone_defconfig
>> @@ -4,7 +4,7 @@ CONFIG_SPL=y
>>   CONFIG_PINEPHONE_LEDS=y
>>   CONFIG_MACH_SUN50I=y
>>   CONFIG_SUNXI_DRAM_LPDDR3_STOCK=y
>> -CONFIG_DRAM_CLK=552
>> +CONFIG_DRAM_CLK=528
>>   CONFIG_DRAM_ZQ=3881949
>>   CONFIG_MMC_SUNXI_SLOT_EXTRA=2
>>   CONFIG_PINEPHONE_DT_SELECTION=y