Re: [PATCH 4/6] dt-bindings: net: add hisilicon-femac

From: Yang Xiwen
Date: Fri Feb 16 2024 - 09:30:24 EST


On 2/16/2024 10:10 PM, Andrew Lunn wrote:
I've tried accessing MDIO address space and MAC controller address space in
u-boot with `md` and `mw` [1]. From the result, i guess the CLK_BUS is the
System Bus clock (AHB Bus clock), and the CLK_MAC is the clock shared by
both MDIO bus and MAC. The MAC has a internal clock divider to divide the
input clock(54MHz in common) to a configurable variable rate.
In general, sharing a clock is not a problem. The clock API does
reference counting. So if two consumers enable the clock, it will not
be disabled until two consumes disable the clock. So it should not be
an issue for both the MAC and the MDIO driver to consume the clock.

However, the funny PHY reset code is going to be key here. We need to
understand that in more detail.

I don't know about details too much, either. All the resources i have is a brief TRM and the downstream linux kernel code[1], U-Boot code[2]. The idea of managing all clocks and resets in MAC driver is taken from hix5hd2_gmac.c(in the same directory).


Talking about details, you commit messages need improving. The commit
message is your chance to answer all the reviewers questions before
they even ask them. Removing a binding was always going to need
justification, so you needed to have that in the commit message. In
order to review a DT bindings, having an overview of what the hardware
actually looks like is needed. So that is something which you can add
to the commit messages.
Thanks for your comment. Also sorry for the inconvenience I brought.

Please take a look at your patches from the perspective of a reviewer,
somebody how knows nothing about this device. What information is
needed to understand the patches?
Will rewrite commit logs in next version.

Andrew

[1]: https://github.com/JasonFreeLab/HiSTBLinuxV100R005C00SPC050/blob/fd20f78ab02934e71474dbb1d933c6ec911b01c9/source/kernel/linux-4.4.y/drivers/net/ethernet/hieth/hieth.c#L1281

[2]: https://github.com/JasonFreeLab/HiSTBLinuxV100R005C00SPC050/blob/fd20f78ab02934e71474dbb1d933c6ec911b01c9/source/boot/fastboot/drivers/net/hisfv300/sys.c#L50

--
Regards,
Yang Xiwen