RE: [PATCH 04/10] ravb: Add support for RZ/G2L SoC

Hi Geert,

Thanks for the feedback

Subject: Re: [PATCH 04/10] ravb: Add support for RZ/G2L SoC

Hi Biju,

On Sun, Oct 3, 2021 at 8:51 AM Biju Das [off-list ref]
wrote:

quoted

quoted

Subject: Re: [PATCH 04/10] ravb: Add support for RZ/G2L SoC On
10/1/21 6:06 PM, Biju Das wrote:

quoted

RZ/G2L SoC has Gigabit Ethernet IP consisting of Ethernet
controller (E-MAC), Internal TCP/IP Offload Engine (TOE) and
Dedicated Direct memory access controller (DMAC).

This patch adds compatible string for RZ/G2L and fills up the
ravb_hw_info struct. Function stubs are added which will be used
by gbeth_hw_info and will be filled incrementally.

   I've always been against this patch -- we get a support for the
GbEther whihc doesn't work after this patch. I believe we should
have the GbEther support in the last patch. of the overall series.

This is the common practice. We use bricks to build a wall. The
function stubs are just Bricks.

After filling stubs, we will add SoC dt and board DT, after that one
will get GBsupport on RZ/G2L platform.

Not "after", but "in parallel".  The stubs will be filled in through the
netdev tree (1), while SoC DT and board DT will go through the renesas-
devel and soc trees (2).

So our main worry is: what happens if you have (2) but not (1)?

Please find the test cases

Case a) (1) and then (2) RootFS mounted on NFS
----------------------------------------------------

root@smarc-rzg2l:~# cat /proc/cmdline
ignore_loglevel nfsrootdebug root=/dev/nfs rw nfsroot=192.168.10.1:/tftpboot/RZ-G2L,nfsvers=3 ip=192.168.10.2
root@smarc-rzg2l:~#

Case b) Have (2) but not (1)? RootFS mounted on USB
----------------------------------------------------

root@smarc-rzg2l:~# cat /proc/cmdline
rw rootwait earlycon root=/dev/sda1
root@smarc-rzg2l:~#

Case c) Have (2) but not (1)? RootFS mounted on NFS
---------------------------------------------------

It stops booting as we haven't filled RX stubs.

[    4.457432]  sda: sda1
[    4.465909] sd 0:0:0:0: [sda] Attached SCSI removable disk


If you look at Case B, that is the current case, which boots without any issues. There is no regression
at all with the current changes submitted.

The only issue is mounting with NFS which won't work as we haven't filled stubs to get full functionality.


Regards,
Biju