Hi Clément,

On Mon, May 2, 2022 at 8:52 AM Clément Léger [off-list ref] wrote:

Le Fri, 29 Apr 2022 12:32:35 -0700,
Jakub Kicinski [off-list ref] a écrit :

quoted

On Fri, 29 Apr 2022 16:34:53 +0200 Clément Léger wrote:

quoted

The Renesas RZ/N1 SoCs features an ethernet subsystem which contains
(most notably) a switch, two GMACs, and a MII converter [1]. This
series adds support for the switch and the MII converter.

The MII converter present on this SoC has been represented as a PCS
which sit between the MACs and the PHY. This PCS driver is probed from
the device-tree since it requires to be configured. Indeed the MII
converter also contains the registers that are handling the muxing of
ports (Switch, MAC, HSR, RTOS, etc) internally to the SoC.

The switch driver is based on DSA and exposes 4 ports + 1 CPU
management port. It include basic bridging support as well as FDB and
statistics support.

Build's not happy (W=1 C=1):

drivers/net/dsa/rzn1_a5psw.c:574:29: warning: symbol 'a5psw_switch_ops' was not declared. Should it be static?
In file included from ../drivers/net/dsa/rzn1_a5psw.c:17:
drivers/net/dsa/rzn1_a5psw.h:221:1: note: offset of packed bit-field ‘port_mask’ has changed in GCC 4.4
  221 | } __packed;
      | ^

Hi Jakub, I only had this one (due to the lack of W=1 C=1 I guess) which
I thought (wrongly) that it was due to my GCC version:

  CC      net/dsa/switch.o
  CC      net/dsa/tag_8021q.o
In file included from ../drivers/net/dsa/rzn1_a5psw.c:17:
../drivers/net/dsa/rzn1_a5psw.h:221:1: note: offset of packed bit-field
  ‘port_mask’ has changed in GCC 4.4 221 | } __packed;
      | ^
  CC      kernel/module.o
  CC      drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.o
  CC      drivers/net/ethernet/stmicro/stmmac/dwmac100_core.o

I'll fix the other errors which are more trivial, however, I did not
found a way to fix the packed bit-field warning.

The "port_mask" field is split across 2 u8s.
What about using u16 instead, and adding explicit padding while
at it? The below gets rid of the warning, while the generated code
is the same.

--- a/drivers/net/dsa/rzn1_a5psw.h
+++ b/drivers/net/dsa/rzn1_a5psw.h

@@ -169,10 +169,11 @@

 struct fdb_entry {
        u8 mac[ETH_ALEN];
-       u8 valid:1;
-       u8 is_static:1;
-       u8 prio:3;
-       u8 port_mask:5;
+       u16 valid:1;
+       u16 is_static:1;
+       u16 prio:3;
+       u16 port_mask:5;
+       u16 reserved:6;
 } __packed;

 union lk_data {

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds