[PATCH v9 1/2] arm-soc: Import initial tango4 device tree

Marc Gonzalez marc_gonzalez at sigmadesigns.com
Thu Nov 19 05:53:18 PST 2015

Måns Rullgård wrote:

> Olof Johansson wrote:
>> Måns Rullgård wrote:
>>> Marc Gonzalez wrote:
>>>> Måns Rullgård wrote:
>>>>> Marc Gonzalez wrote:
>>>>>> +           clkgen: clkgen at 10000 {
>>>>>> +                   compatible = "sigma,tango4-clkgen";
>>>>>> +                   reg = <0x10000 0x40>;
>>>>>> +                   clocks = <&xtal>;
>>>>>> +                   clock-output-names = "cpuclk", "sysclk";
>>>>>> +                   #clock-cells = <1>;
>>>>>> +           };
>>>>> Would you please consider using my clock driver that matches the actual
>>>>> hardware, supports all the clock outputs required for USB, SATA, etc,
>>>>> and works on tango3 as well?
>>>> I was hoping to take baby steps to work up to a fully-functional port.
>>>> The first step (in my mind) is this submission: a minimal port which
>>>> only requires the two "main" clocks.
>>>> The next step will add to the minimal port by supporting as many
>>>> peripherals as possible, as well as their required clocks.
>>> But the code already exists.  Why start over?

"La perfection est atteinte, non pas lorsqu'il n'y a plus rien à ajouter,
mais lorsqu'il n'y a plus rien à retirer."

For example, what is the point of not ignoring sysclk_premux, when the boot
loader has always hard-coded "PLL1 drives sys_clk, PLL2 drives cd_clk".

Having one clk driver for tango3, and another for tango4 allows you to
submit your own tango3 clk driver, and I can then ignore all the insane
tango3 clk legacy, and focus on the tango4 clean-ups. Would that work
for you?

(BTW, are you aware that the clk maintainers will NAK your clk driver in
its current form, based on the fact that they insist on a single node
for the entire clkgen block?)

>> Måns, I don't understand your role in this. Can you clarify?
> Oh, I'm just the guy who did all the work and then got screwed over by
> Sigma.

Here's the sequence of events, to the best of my recollection.

In 2010, you hacked the Popcorn Hour C-200 (Tango3 SoC)
In 2014-11, I mentioned on LAKML that I planned to upstream Sigma's kernel
In 2014-12, you pushed your tango3 port to github (3.18 at the time IIRC)
In late 2015-02, you blogged about your work
I contacted you the next day, and you offered your services.
You met management in late March.
Then radio silence for several months.
Sometime in July, I was told the deal had fallen apart :-(

>> If you've already done a port, why haven't you contributed it
>> yourself?
> Because it's not yet in a shape to be contributed, just like Marc's
> isn't.

Are you saying the DT needs to be perfect on the first submission?
Has this been true for other mach?

>> Why are you driving Marc's work from the back seat like this instead
>> of submitting your own work?
> I have submitted bits and pieces.  It's a slow process.

Indeed. Especially when a maintainer NAKs a patch because one used
'unsigned' instead of 'unsigned int'.


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