Hello Daniel, Thanks for your help!
On 6/8/19 6:51 AM, Daniel Golle wrote: > Hi Daniel, > > On Sat, Jun 08, 2019 at 04:06:54AM -0500, Daniel Santos wrote: >> Hello, >> >> I need to change auto-negotiate, speed and duplex for a port on my >> mt7620a-based device, but I'm not quite certain that I understand the >> structure here. When using ethtool on eth0 I always get ENODEV, >> apparently because priv->phy_dev is always NULL in fe_get_link_ksettings >> of drivers/net/ethernet/mtk/ethtool.c. But I'm being told that eth0 is >> only an internal device between the µC and the switch hardware, so it >> isn't even the one I need to change. > That's correct. It always helps when my idea about what I'm doing matches reality. >> If this is true, then it looks like I will need to implement a >> get_port_link function for struct switch_dev_ops? Can anybody confirm >> this to be the case? Also, are there any examples aside from the >> Broadcom drivers? I have the mt7620 programmer's guide and it specifies >> the registers I need to change. > Currently MT7620 still uses our legacy swconfig switch driver, which > also doesn't support setting autoneg, speed and duplex. However, rather > than implementing it there, it'd be great to add support for the FE- > version of the MT7530 swtich found in the MT7620(A/N) WiSoC to the now > upstream DSA driver[1]. Ok, this makes much more sense now. So swconfig is on its way out in favor of DSA (which I've never heard of until now)? I presume this will also abstract away changes of ethtool to netlink-based instead of ioctl on a random socket as well? > While this driver was originally intended for > use with standalone MT7530 GE switch chip or the ARM-based MT7623 SoC, > the same switch fabric is also implemented in MT7621 and support for > that chip was added to the driver recently[2]. MT7620 basically also > features the same switch internally, however, it comes with only one > CPU port, supports only FastEthernet and lacks some of the management > counters. > > Assuming your MT7620 datasheet includes the decription of the MT7530 > switch registers, it'd be great if you can help working on supporting > MT7620 in the DSA driver as well -- gaining per-port ethtool support > as a reward :) Wonderful! So if I understand correctly, this is the same switch hardware (internally at least), so has all of the same MAC and MII registers on 7530, 7621, 7620, etc? For now I have to get a fix for a customer on a 3.18 kernel, so I'll be doing the swconfig first and then see how much time we can put into the DSA implementation. > > Cheers > > > Daniel > > > [1]: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/dsa/mt7530.c > [2]: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ddda1ac116c852bb969541ed53cffef7255c4961 > Also, would you happen to know why the mt7620 mdio driver is using a 32-bit read for MII registers that are 32-bit? For example, in _mt7620_mii_read. It looks like some of this can use some improved error management, since return codes are being ignored in a few places. >From what I can tell thus far, it looks like these MII registers are standardized, so the "generic" version might do most or all of what I need in some cases. But as far as implementing DSA, I guess I'll have to examine the mainlined driver and see how it works. I just didn't have a struct phy_device to work with when trying to get it to work. Thanks, Daniel
