On 08/29/2018 07:47 PM, Tony Lindgren wrote:
* Grygorii Strashko <grygorii.strashko@xxxxxx> [180830 00:12]:
Hi Tony,
On 08/29/2018 10:00 AM, Tony Lindgren wrote:
The current cpsw usage for cpsw-phy-sel is undocumented but is used for
all the boards using cpsw. And cpsw-phy-sel is not really a child of
the cpsw device, it lives in the system control module instead.
Let's document the existing usage, and improve it a bit where we prefer
to use a phandle instead of a child device for it. That way we can
properly describe the hardware in dts files for things like genpd.
I'm ok with this series, but I really don't like cpsw-phy-sel in general.
Yeah this binding predates any standards. This series
only fixes the nasty issue of cpsw claiming a module as a
child that's outside it's IO range.
It was introduced long time back and now I'm thinking about possibility to replace it with
one of current generic interfaces - for example mux-controller.
Each port will control up to 3 muxes (port mode, idmode and rmii_ext_clk) and
transform phy-mode => mux states.
What do you think?
Sure a mux-controller here makes sense.
Another option is to use phy, but it'd be complicated.
For the port muxes, how about a phy driver just using
a pinctrl driver?
In general, it seems cpsw is just an interconnect instance
(L4_FAST) with a control module (CPSW_WR) and a pile of
independent other modules. That's described nicely in
am437x TRM chapter "2.1.4 L4 Fast Peripheral Memory Map".
So from that point of view the binding reg entries right
now are all wrong :)
TRM not consistent - for am5 it's one MMIO region.
In the long run cpsw should be really treated as an
interconnect instance with it's control module providing
standard Linux framework services such as clock /
regulator / phy / pinctrl / iio whatever for the other
modules.
Just my 2c based on looking at the interconnect, I'm
not too familiar with cpsw otherwise.
It's not separate modules. this is composite module which have only one
fck/ick and most of blocks can't even function without each other.
Above might be the case for Keystone 2, but not omap CPSW.
Keystone 2 - has packet processor, security accelerator, queue manager
in addition to its basic switch block.
--
regards,
-grygorii
