[U-Boot] [PATCH 1/5] sun6i: Make dram clk and zq value Kconfig options

[Hans de Goede]

Hi,

On 11/18/2014 03:07 PM, Ian Campbell wrote:
> On Tue, 2014-11-18 at 12:32 +0100, Hans de Goede wrote:
>> Hi,
>>
>> On 11/17/2014 07:54 PM, Ian Campbell wrote:
>>> On Sun, 2014-11-16 at 17:16 +0100, Hans de Goede wrote:
>>>
>>>> +config DRAM_ZQ
>>>> +	int "sun6i dram zq value" if EXPERT
>>>> +	default 123
>>>
>>> == 0x7b, which differs from the previous default of 0x78 (not by much,
>>> but still)
>>
>> Right, this is deliberate as I've gotten access to more boards, 123 seems
>> a better default (this is also what most A10 / A13 / A20 boards use).
> 
> Please mention this in the commit log.

Fixed in my personal tree.

>>>> diff --git a/configs/Colombus_defconfig b/configs/Colombus_defconfig
>>>> index bef568d..5e245a3 100644
>>>> --- a/configs/Colombus_defconfig
>>>> +++ b/configs/Colombus_defconfig
>>>> @@ -4,3 +4,5 @@ CONFIG_FDTFILE="sun6i-a31-colombus.dtb"
>>>>  +S:CONFIG_ARCH_SUNXI=y
>>>>  +S:CONFIG_MACH_SUN6I=y
>>>>  +S:CONFIG_TARGET_COLOMBUS=y
>>>> ++S:CONFIG_DRAM_CLK=288
>>>> ++S:CONFIG_DRAM_ZQ=379
>>>
>>> Do these actually take affect if CONFIG_EXPERT=n?
>>
>> Ugh, I just checked, and no they don't.
>>
>>> Perhaps CONFIG_TARGET_COLOMBUS should select DRAM_CLK == 288 and
>>> DRAM_CLK should be a hidden option?
>>
>> I would prefer to keep these inside the defconfig's so that for
>> adding a new board only a defconfig needs to be added.
>>
>> Currently the only CONFIG_TARGET_BOARD we actually use in u-boot is
>> the bananapi gmac tx clk delay tweak, and I would actually like
>> to keep things that way. Actually thinking more about this, I
>> think that that should be turned into a GMAC specific Kconfig option
>> and all the CONFIG_TARGET_BOARD stuff should be dropped, as it is
>> just a drag causing extra maintenance going forward.
> 
> Hrm, I'm not sure yet which way I fall on this question.

Ok, so how do you feel no that you've slept a night on it ?

May main reason for wanting to get rid of this is that it does not
buy us much, unless we start adding things like select FOO in there
as you suggested, but that seems less transparent then having all the
board specific settings in the _defconfig. To me the ideal scenario
is that adding a new board is just adding a new _defconfig, and
likewise figuring out what board specific settings are done for
a certain board also is just a manner of inspecting the _defconfig,
and not 2 - 3 different files.

If we decide we want everything in the _defconfig, and thus
CONFIG_TARGET_BOARD does not select / enable anything, iow is
essentially unused, then we might just as well drop it.

>> So is there a way to not show a choice to the user unless EXPERT
>> mode is set, and still override it from Kconfig ?
> 
> Not AFAIK, but I'm not expert (no pun intended) in Kconfig.
> 
>> If that is not (easily) possible, then I guess we will just need
>> to not make these "if EXPERT".
> 
> Probably :-(

Ok, so I've dropped the "if EXPERT" from the version in my personal tree.

Regards,

Hans