[U-Boot] [RFC] Merge all ns16550 dm serial drivers into one

[Simon Glass]

Hi Stephen,

On 14 August 2015 at 10:58, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 08/14/2015 10:50 AM, Simon Glass wrote:
>>
>> Hi Bin,
>>
>> On 14 August 2015 at 03:18, Bin Meng <bmeng.cn at gmail.com> wrote:
>>>
>>> Hi,
>>>
>>> Currently there are 5 dm serial drivers, all of which are ns16550
>>> compatible drivers. They are:
>>>
>>>    serial_omap.c
>>>    serial_dw.c
>>>    serial_tegra.c
>>>    serial_x86.c
>>>    serial_ppc.c
>>>
>>> All these drivers are pretty much similar. I think we can justmerge
>>> these into one ns16550 driver.
>>>
>>> If you think this is necessary, I will send a patch series to do this.
>>
>>
>> The tegra one is there because it needs an input clock and Stephen
>> didn't want to add this to the device tree binding (the kernel has a
>> clock framework which gets around this problem).
>>
>> After that I followed the same pattern. I would support updating the
>> binding to support an input clock. Even with the new clock framework
>> in U-Boot it might be painful to fit it into SPL in some cases.
>
>
> The clock is already in the DT, in both Linux and U-Boot's copy, at least
> for Tegra DTs:
>
>         uarta: serial at 0,70006000 {
>                 compatible = "nvidia,tegra124-uart", ...
> ...
>                 clocks = <&tegra_car TEGRA124_CLK_UARTA>;
>

I mean the clock-frequency property. However if there is a plan to
implement the clock framework in U-Boot that would be good too.

Regards,
Simon