On 24 February 2015 at 22:51, Andrew Lunn [off-list ref] wrote:

On Tue, Feb 24, 2015 at 06:42:07PM +0100, Rafa?? Mi??ecki wrote:

quoted

BCM53xx is series of Broadcom Ethernet switches that can be found in
various (mostly home) routers.
They are quite simple switches with mainly just support for:
1) Tagging incoming packets (PVID)
2) Untagging outgoing packets
3) Forwarding all packets across a single VLAN

This driver is split into common code (module) and bus specific code.
Right now only PHY (MDIO) support is included, other could follow after
accepting this driver. It was successfully tested on BCM4706 SoC with
BCM53125.

You could notice it's yet another try of submitting b53 driver. This
time it was modified to use recently introduced switchdev API which
hopefully make it possible to accept it mainline.

Signed-off-by: Rafa?? Mi??ecki <zajec5@gmail.com>
---
Example usage. My BCM4706 router has switch with 6 ports:
0: WAN port
1-4: LAN ports
8: CPU connected port (on-SoC Ethernet device)

I decided to use VLAN 1 for WAN and VLAN 2 for LAN. I was able to
successfully configure it using:

bridge vlan add vid 1 dev sw0p1 pvid untagged
bridge vlan add vid 1 dev sw0p2 pvid untagged
bridge vlan add vid 1 dev sw0p3 pvid untagged
bridge vlan add vid 1 dev sw0p4 pvid untagged
bridge vlan add vid 1 dev sw0p8

bridge vlan add vid 2 dev sw0p0 pvid untagged
bridge vlan add vid 2 dev sw0p8
---
 drivers/net/phy/Kconfig          |   2 +
 drivers/net/phy/Makefile         |   1 +
 drivers/net/phy/b53/Kconfig      |  12 +
 drivers/net/phy/b53/Makefile     |   2 +
 drivers/net/phy/b53/b53_common.c | 961 +++++++++++++++++++++++++++++++++++++++
 drivers/net/phy/b53/b53_mdio.c   | 418 +++++++++++++++++
 drivers/net/phy/b53/b53_priv.h   | 299 ++++++++++++
 drivers/net/phy/b53/b53_regs.h   | 313 +++++++++++++

Hi Rafa??

I have a question about the location. Why drivers/net/phy?

It wasn't really my idea, all out-of-tree switch drivers
developed/used in OpenWrt are placed in drivers/net/phy/. My guess is
that it's because many of them register themselves as PHY drivers
(phy_driver_register, or module_phy_driver helper). AFAIK all mainline
PHY drivers all located in this directory. It's the same about
b53_mdio.c - we call phy_driver_register [0] for 3 different phy_id-s.

Now, there may be some exceptions, indeed. For example some devices
with BCM53xx switches use memory mapped registers instead of
MII-accessible registers. This means that after adding support for
such devices we'll get also some platform driver in
drivers/net/phy/b53/ (most likely b53_mmap.c). I'm not sure how much
acceptable it is. It seems we already have some non-PHY drivers in
drivers/net/phy/ like spi_ks8995.c. So maybe it's also acceptable to
have there some platform drivers?

That said, I'm not aware of any better place for switchdev drivers.
Unless we create some new directory like drivers/net/switch/ or
similar. But won't that somehow duplicate drivers/net/phy/ then?

[0] Actually it seems we should simply use module_phy_driver in
b53_mdio.c, I'll do this in V2!

-- 
Rafał