Re: [PATCH 2/2] clk: meson-g12a: Add AO Clock controller driver

From: Jian Hu
Date: Mon Aug 27 2018 - 23:35:26 EST

Hi: Jerome

On 2018/8/27 21:07, Jerome Brunet wrote:
On Fri, 2018-08-24 at 21:34 +0800, Jian Hu wrote:

I am confued about aoclk81's parent clocks.

I can not get the example of axg audio clock driver, Could you provide
the link? Had it merged into clk-meson.git?

Yes and mainline as well : drivers/clk/meson/axg-audio.c

Basically this driver is creating bypass input clocks (audio_pclk, mst_in[0-9],
etc...) .

This allows to collect input clocks from DT (like any consumer should) will
keeping constant in the controller clock tree.

From what I've seen of your controller drivers, the EE controller should have
one input, the AO should have 3.


I still can not get the example meaning in axg audio driver.

In 26 page of A113D_Datasheet V0.7 20170725-Baylibre.pdf,We can see the aoclk81 has two parents. clk81 and ao_slow_clk. I can not get 3 parents.

-------| \ aoclk81
src0 |\ | |-------------------
-----| \ ao_slow_clk | |
| |---------------------| /
-----| / |/

src0 is from xtal, if can generate 32k clock, but it is never used.
src1 is from gpio clock, It is never used. If necessaryï the ao_slow_clk maybe described.

So why aoclk81 has 3 parents?