Messages in this thread Patch in this message | | | Subject | Re: [PATCH] net: phy: micrel: make *-skew-ps check more lenient | From | Matthias Schiffer <> | Date | Wed, 13 Oct 2021 13:01:26 +0200 |
| |
On Wed, 2021-10-13 at 10:18 +0000, Philippe Schenker wrote: > On Wed, 2021-10-13 at 10:46 +0200, Matthias Schiffer wrote: > > On Wed, 2021-10-13 at 08:25 +0000, Philippe Schenker wrote: > > > On Tue, 2021-10-12 at 12:34 +0200, Matthias Schiffer wrote: > > > > It seems reasonable to fine-tune only some of the skew values when > > > > using > > > > one of the rgmii-*id PHY modes, and even when all skew values are > > > > specified, using the correct ID PHY mode makes sense for > > > > documentation > > > > purposes. Such a configuration also appears in the binding docs in > > > > Documentation/devicetree/bindings/net/micrel-ksz90x1.txt, so the > > > > driver > > > > should not warn about it. > > > > > > I don't think your commit message is right. The rgmii-*id PHY modes > > > are > > > no longer just for documentation purposes on KSZ9031 PHY. They are > > > used > > > to set the skew-registers according to . > > > > Yes, this was implemented in [1]. The commit message explicitly states > > that fine-tuning is still possible using *-skew-ps. > > > > > > > > The warning is there, that in case you override the skew registers > > > of > > > one of the modes rgmii-id, rgmii-txid, rgmii-rxid with *-skew-ps > > > settings in DT. > > > > The "rgmii" mode should not be handled differently from "rgmii-*id" in > > my opinion. Otherwise for a device that is basically "rgmii-id", but > > requires slight fine-tuning, you have to set the mode to the incorrect > > value "rgmii" in the DTS to avoid this warning. > > Now I have understood your argument. But then I suggest to delete the > warning entirely as it completely changes its meaning with that patch. > > Philippe
The KSZ9031 also supports MII and GMII though. I think it makes sense to keep the warning for these cases (which is why I reworded the warning the way I did).
> > > > > > > > > > > Therefore I also think the warning is valuable and should be kept. > > > We > > > may want to reword it though. > > > > > > Philippe > > > > [1] > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/net/phy/micrel.c?id=bcf3440c6dd78bfe5836ec0990fe36d7b4bb7d20 > > > > > > > > > > > > > > > Signed-off-by: Matthias Schiffer > > > > <matthias.schiffer@ew.tq-group.com> > > > > --- > > > > drivers/net/phy/micrel.c | 4 ++-- > > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c > > > > index c330a5a9f665..03e58ebf68af 100644 > > > > --- a/drivers/net/phy/micrel.c > > > > +++ b/drivers/net/phy/micrel.c > > > > @@ -863,9 +863,9 @@ static int ksz9031_config_init(struct > > > > phy_device > > > > *phydev) > > > > MII_KSZ9031RN_TX_DATA_PAD_SKEW, 4, > > > > tx_data_skews, 4, &update); > > > > > > > > - if (update && phydev->interface != > > > > PHY_INTERFACE_MODE_RGMII) > > > > + if (update && !phy_interface_is_rgmii(phydev)) > > > > phydev_warn(phydev, > > > > - "*-skew-ps values should be > > > > used > > > > only with phy-mode = \"rgmii\"\n"); > > > > + "*-skew-ps values should be > > > > used > > > > only with RGMII PHY modes\n"); > > > > > > > > /* Silicon Errata Sheet (DS80000691D or > > > > DS80000692D): > > > > * When the device links in the 1000BASE-T slave > > > > mode > > > > only, > > > > > > > >
| |