[U-Boot] [PATCH] armv8/fsl-layerscape: fdt: remove SYSCLK frequency fixup for ls1012a

[york sun]

On 01/20/2017 02:14 PM, Scott Wood wrote:
> On Fri, 2017-01-20 at 21:38 +0000, york sun wrote:
>> On 01/20/2017 01:36 PM, Scott Wood wrote:
>>>
>>> On Fri, 2017-01-20 at 16:28 +0000, york sun wrote:
>>>>

<snip>

>>>>
>>>> Why fixing up this clock causes incorect frequency value? The macro
>>>> CONFIG_SYS_CLK_FREQ is defined as 125MHz for ls1012a.
>>> Because ls1012a has two different input frequencies -- 125 MHz for the
>>> platform PLL and 100 MHz for the core PLLs.  When we added a second fixed-
>>> clock node for the latter, U-Boot was overwriting it.
>>>
>>> While the ifdef solves this immediate problem, it doesn't fix the
>>> underlying
>>> problem that this fixup is overly broad.  It should identify the specific
>>> node
>>> it's looking for, and not overwrite every fixed-clock node it finds.
>>>
>> So current code tries to fix up any node with "fixed-clock"? That's not
>> good. What if we have multiple fixed clocks?
>>
>
> That is exactly the problem.  This patch avoids the issue on ls1012a but not
> in general.
>

Then a proper fix would be check the clock name or compatible. If none 
of them exists, we should fix the device tree first.

York