Re: [PATCH 11/14] drivers: net: dsa: qca8k: apply switch revision fix

From: Ansuel Smith
Date: Sat Apr 24 2021 - 17:20:38 EST


On Thu, Apr 22, 2021 at 07:02:37PM -0700, Florian Fainelli wrote:
>
>
> On 4/22/2021 6:47 PM, Ansuel Smith wrote:
> > qca8k require special debug value based on the switch revision.
> >
> > Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
> > ---
> > drivers/net/dsa/qca8k.c | 23 +++++++++++++++++++++--
> > 1 file changed, 21 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
> > index 193c269d8ed3..12d2c97d1417 100644
> > --- a/drivers/net/dsa/qca8k.c
> > +++ b/drivers/net/dsa/qca8k.c
> > @@ -909,7 +909,7 @@ qca8k_phylink_mac_config(struct dsa_switch *ds, int port, unsigned int mode,
> > {
> > const struct qca8k_match_data *data;
> > struct qca8k_priv *priv = ds->priv;
> > - u32 reg, val;
> > + u32 phy, reg, val;
> >
> > /* get the switches ID from the compatible */
> > data = of_device_get_match_data(priv->dev);
> > @@ -928,7 +928,26 @@ qca8k_phylink_mac_config(struct dsa_switch *ds, int port, unsigned int mode,
> > case 3:
> > case 4:
> > case 5:
> > - /* Internal PHY, nothing to do */
> > + /* Internal PHY, apply revision fixup */
> > + phy = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
> > + switch (priv->switch_revision) {
> > + case 1:
> > + /* For 100M waveform */
> > + qca8k_phy_dbg_write(priv, phy, 0, 0x02ea);
> > + /* Turn on Gigabit clock */
> > + qca8k_phy_dbg_write(priv, phy, 0x3d, 0x68a0);
> > + break;
> > +
> > + case 2:
> > + qca8k_phy_mmd_write(priv, phy, 0x7, 0x3c, 0x0);
> > + fallthrough;
> > + case 4:
> > + qca8k_phy_mmd_write(priv, phy, 0x3, 0x800d, 0x803f);
> > + qca8k_phy_dbg_write(priv, phy, 0x3d, 0x6860);
> > + qca8k_phy_dbg_write(priv, phy, 0x5, 0x2c46);
> > + qca8k_phy_dbg_write(priv, phy, 0x3c, 0x6000);
> > + break;
>
> This would be better done with a PHY driver that is specific to the
> integrated PHY found in these switches, it would provide a nice clean
> layer and would allow you to expose additional features like cable
> tests, PHY statistics/counters, etc.

I'm starting to do some work with this and a problem arised. Since these
value are based on the switch revision, how can I access these kind of
data from the phy driver? It's allowed to declare a phy driver in the
dsa directory? (The idea would be to create a qca8k dir with the dsa
driver and the dedicated internal phy driver.) This would facilitate the
use of normal qca8k_read/write (to access the switch revision from the
phy driver) using common function?

> --
> Florian