Re: [PATCH net-next 4/5] net: phy: broadcom: Add support for WAKE_FILTER

[Vincent MAILHOL]

On Thu. 26 Oct. 2023 at 10:10, Vincent MAILHOL
<mailhol.vincent@xxxxxxxxxx> wrote:
> Hi Florian,
>
> On Thu. 26 Oct. 2023 at 02:32, Florian Fainelli
> <florian.fainelli@xxxxxxxxxxxx> wrote:
> > Since the PHY is capable of matching any arbitrary Ethernet MAC
> > destination as a programmable wake-up pattern, add support for doing
> > that using the WAKE_FILTER and ethtool::rxnfc API. For instance, in
> > order to wake-up from the Ethernet MAC address corresponding to the IPv4
> > multicast IP address of 224.0.0.251 (e.g.: multicast DNS), one could do:
> >
> > ethtool -N eth0 flow-type ether dst 01:00:5e:00:00:fb loc 0 action -2
> > ethtool -n eth0
> > Total 1 rules
> >
> > Filter: 0
> >         Flow Type: Raw Ethernet
> >         Src MAC addr: 00:00:00:00:00:00 mask: FF:FF:FF:FF:FF:FF
> >         Dest MAC addr: 01:00:5E:00:00:FB mask: 00:00:00:00:00:00
> >         Ethertype: 0x0 mask: 0xFFFF
> >         Action: Wake-on-LAN
> > ethtool -s eth0 wol f
>
> Nit: indent the commands and their output with two spaces.
>
> > Signed-off-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
> > ---
> >  drivers/net/phy/bcm-phy-lib.c | 195 +++++++++++++++++++++++++++++++++-
> >  drivers/net/phy/bcm-phy-lib.h |   5 +
> >  drivers/net/phy/broadcom.c    |   2 +
> >  3 files changed, 201 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
> > index 876f28fd8256..cfbeedc5ee81 100644
> > --- a/drivers/net/phy/bcm-phy-lib.c
> > +++ b/drivers/net/phy/bcm-phy-lib.c
> > @@ -827,7 +827,8 @@ EXPORT_SYMBOL_GPL(bcm_phy_cable_test_get_status_rdb);
> >                                          WAKE_MCAST | \
> >                                          WAKE_BCAST | \
> >                                          WAKE_MAGIC | \
> > -                                        WAKE_MAGICSECURE)
> > +                                        WAKE_MAGICSECURE | \
> > +                                        WAKE_FILTER)
>
> Nit: you may want to have the closing bracket on a newline to have a
> cleaner diff for new future additions.
>
> >  int bcm_phy_set_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
> >  {
> > @@ -881,6 +882,12 @@ int bcm_phy_set_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
> >         ctl &= ~BCM54XX_WOL_DIR_PKT_EN;
> >         ctl &= ~(BCM54XX_WOL_SECKEY_OPT_MASK << BCM54XX_WOL_SECKEY_OPT_SHIFT);
> >
> > +       /* For WAKE_FILTER, we have already programmed the desired MAC DA
> > +        * and associated mask by the time we get there.
> > +        */
> > +       if (wol->wolopts & WAKE_FILTER)
> > +               goto program_ctl;
> > +
> >         /* When using WAKE_MAGIC, we program the magic pattern filter to match
> >          * the device's MAC address and we accept any MAC DA in the Ethernet
> >          * frame.
> > @@ -935,6 +942,7 @@ int bcm_phy_set_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
> >                         return ret;
> >         }
> >
> > +program_ctl:
> >         if (wol->wolopts & WAKE_MAGICSECURE) {
> >                 ctl |= BCM54XX_WOL_SECKEY_OPT_6B <<
> >                        BCM54XX_WOL_SECKEY_OPT_SHIFT;
> > @@ -999,6 +1007,16 @@ void bcm_phy_get_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
> >         if (!(ctl & BCM54XX_WOL_EN))
> >                 return;
> >
> > +       ret = bcm_phy_read_exp(phydev, BCM54XX_WOL_SEC_KEY_8B);
> > +       if (ret < 0)
> > +               return;
> > +
> > +       /* Mutualy exclusive with other modes */
> > +       if (ret) {
> > +               wol->wolopts |= WAKE_FILTER;
> > +               return;
> > +       }
> > +
> >         for (i = 0; i < sizeof(da) / 2; i++) {
> >                 ret = bcm_phy_read_exp(phydev,
> >                                        BCM54XX_WOL_MPD_DATA2(2 - i));
> > @@ -1066,6 +1084,181 @@ int bcm_phy_led_brightness_set(struct phy_device *phydev,
> >  }
> >  EXPORT_SYMBOL_GPL(bcm_phy_led_brightness_set);
> >
> > +static int bcm_phy_get_rule(struct phy_device *phydev,
> > +                           struct ethtool_rxnfc *nfc,
> > +                           int loc)
> > +{
> > +       u8 da[ETH_ALEN];
> > +       unsigned int i;
> > +       int ret;
> > +
> > +       if (loc != 0)
> > +               return -EINVAL;
> > +
> > +       memset(nfc, 0, sizeof(*nfc));
> > +       nfc->flow_type = ETHER_FLOW;
> > +       nfc->fs.flow_type = ETHER_FLOW;
> > +
> > +       for (i = 0; i < sizeof(da) / 2; i++) {
> > +               ret = bcm_phy_read_exp(phydev,
> > +                                      BCM54XX_WOL_MPD_DATA2(2 - i));
> > +               if (ret < 0)
> > +                       return ret;
> > +
> > +               da[i * 2] = ret >> 8;
> > +               da[i * 2 + 1] = ret & 0xff;
>
> This looks like an endianness conversion (I can not tell if this is
> big to little or the opposite)...

Oopsy! On second look, this is an open coded cpu to big endian
conversion. So the question I should have asked is:

  why not use the put_unaligned_be16() helper here?

Below comments still remain.

> > +       }
> > +       ether_addr_copy(nfc->fs.h_u.ether_spec.h_dest, da);
> > +
> > +       for (i = 0; i < sizeof(da) / 2; i++) {
> > +               ret = bcm_phy_read_exp(phydev,
> > +                                      BCM54XX_WOL_MASK(2 - i));
> > +               if (ret < 0)
> > +                       return ret;
> > +
> > +               da[i * 2] = ~(ret >> 8);
> > +               da[i * 2 + 1] = ~(ret & 0xff);
> > +       }
> > +       ether_addr_copy(nfc->fs.m_u.ether_spec.h_dest, da);
> > +
> > +       ret = bcm_phy_read_exp(phydev, BCM54XX_WOL_INNER_PROTO);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       nfc->fs.h_u.ether_spec.h_proto = be16_to_cpu(ret);
>
> ... but here it is big endian to cpu endian? It does not look coherent.
>
> Also, did you run parse to check your endianness conversions?
>
>   https://www.kernel.org/doc/html/latest/dev-tools/sparse.html
>
> For example, I would have expected htons() (a.k.a. cpu_to_be16())
> instead of be16_to_cpu().
>
> > +       nfc->fs.ring_cookie = RX_CLS_FLOW_WAKE;
> > +       nfc->fs.location = 0;
> > +
> > +       return 0;
> > +}
> > +
> > +static int bcm_phy_set_rule(struct phy_device *phydev,
> > +                           struct ethtool_rxnfc *nfc)
> > +{
> > +       int ret = -EOPNOTSUPP;
> > +       unsigned int i;
> > +       __be16 h_proto;
> > +       const u8 *da;
> > +
> > +       /* We support only matching on the MAC DA with a custom mask and
> > +        * optionally with a specific Ethernet type, reject anything else.
> > +        */
> > +       if (nfc->fs.ring_cookie != RX_CLS_FLOW_WAKE ||
> > +           (nfc->fs.location != 0 &&
> > +            nfc->fs.location != RX_CLS_LOC_ANY &&
> > +            nfc->fs.location != RX_CLS_LOC_FIRST) ||
> > +           nfc->fs.flow_type != ETHER_FLOW ||
> > +           !is_zero_ether_addr(nfc->fs.h_u.ether_spec.h_source) ||
> > +           !is_zero_ether_addr(nfc->fs.m_u.ether_spec.h_source))
> > +               return ret;
> > +
> > +       ret = bcm_phy_read_exp(phydev, BCM54XX_WOL_SEC_KEY_8B);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       if (ret)
> > +               return -EBUSY;
> > +
> > +       if (nfc->fs.location == RX_CLS_LOC_ANY ||
> > +           nfc->fs.location == RX_CLS_LOC_FIRST)
> > +               nfc->fs.location = 0;
> > +
> > +       da = nfc->fs.h_u.ether_spec.h_dest;
> > +       for (i = 0; i < ETH_ALEN / 2; i++) {
> > +               ret = bcm_phy_write_exp(phydev,
> > +                                       BCM54XX_WOL_MPD_DATA2(2 - i),
> > +                                       da[i * 2] << 8 | da[i * 2 + 1]);
> > +               if (ret < 0)
> > +                       return ret;
> > +       }
> > +
> > +       da = nfc->fs.m_u.ether_spec.h_dest;
> > +       for (i = 0; i < ETH_ALEN / 2; i++) {
> > +               ret = bcm_phy_write_exp(phydev,
> > +                                       BCM54XX_WOL_MASK(2 - i),
> > +                                       da[i * 2] << 8 | da[i * 2 + 1]);
> > +               if (ret < 0)
> > +                       return ret;
> > +       }
> > +
> > +       /* Restore default inner protocol field unless overridden by the flow
> > +        * specification.
> > +        */
> > +       h_proto = be16_to_cpu(nfc->fs.h_u.ether_spec.h_proto);
> > +       if (!h_proto)
> > +               h_proto = ETH_P_8021Q;
> > +
> > +       ret = bcm_phy_write_exp(phydev, BCM54XX_WOL_INNER_PROTO,
> > +                               h_proto);
> > +       if (ret)
> > +               return ret;
> > +
> > +       /* Use BCM54XX_WOL_SEC_KEY_8B as a scratch register to record
> > +        * that we installed a filter rule.
> > +        */
> > +       return bcm_phy_write_exp(phydev, BCM54XX_WOL_SEC_KEY_8B, 1);
> > +}
> > +
> > +int bcm_phy_get_rxnfc(struct phy_device *phydev,
> > +                     struct ethtool_rxnfc *cmd, u32 *rule_locs)
> > +{
> > +       int err = 0, rule_cnt = 0;
> > +
> > +       err = bcm_phy_read_exp(phydev, BCM54XX_WOL_SEC_KEY_8B);
> > +       if (err < 0)
> > +               return err;
> > +
> > +       rule_cnt = err;
> > +       err = 0;
> > +
> > +       switch (cmd->cmd) {
> > +       case ETHTOOL_GRXCLSRLCNT:
> > +               cmd->rule_cnt = rule_cnt;
> > +               cmd->data = 1 | RX_CLS_LOC_SPECIAL;
> > +               break;
> > +       case ETHTOOL_GRXCLSRULE:
> > +               err = bcm_phy_get_rule(phydev, cmd, cmd->fs.location);
> > +               break;
> > +       case ETHTOOL_GRXCLSRLALL:
> > +               if (rule_cnt)
> > +                       rule_locs[0] = 0;
> > +               cmd->rule_cnt = rule_cnt;
> > +               cmd->data = 1;
> > +               break;
> > +       default:
> > +               err = -EOPNOTSUPP;
> > +               break;
> > +       }
> > +
> > +       return err;
> > +}
> > +EXPORT_SYMBOL_GPL(bcm_phy_get_rxnfc);
> > +
> > +int bcm_phy_set_rxnfc(struct phy_device *phydev,
> > +                     struct ethtool_rxnfc *cmd)
> > +{
> > +       int err = 0;
> > +
> > +       switch (cmd->cmd) {
> > +       case ETHTOOL_SRXCLSRLINS:
> > +               err = bcm_phy_set_rule(phydev, cmd);
> > +               break;
> > +       case ETHTOOL_SRXCLSRLDEL:
> > +               if (cmd->fs.location != 0)
> > +                       return err;
> > +
> > +               err = bcm_phy_write_exp(phydev, BCM54XX_WOL_SEC_KEY_8B, 0);
> > +               break;
> > +       default:
> > +               err = -EOPNOTSUPP;
> > +               break;
> > +       }
> > +
> > +       return err;
> > +}
> > +EXPORT_SYMBOL_GPL(bcm_phy_set_rxnfc);
> > +
> >  MODULE_DESCRIPTION("Broadcom PHY Library");
> >  MODULE_LICENSE("GPL v2");
> >  MODULE_AUTHOR("Broadcom Corporation");
> > diff --git a/drivers/net/phy/bcm-phy-lib.h b/drivers/net/phy/bcm-phy-lib.h
> > index b52189e45a84..7081edcec06b 100644
> > --- a/drivers/net/phy/bcm-phy-lib.h
> > +++ b/drivers/net/phy/bcm-phy-lib.h
> > @@ -121,4 +121,9 @@ irqreturn_t bcm_phy_wol_isr(int irq, void *dev_id);
> >  int bcm_phy_led_brightness_set(struct phy_device *phydev,
> >                                u8 index, enum led_brightness value);
> >
> > +int bcm_phy_get_rxnfc(struct phy_device *phydev,
> > +                     struct ethtool_rxnfc *nfc, u32 *rule_locs);
> > +int bcm_phy_set_rxnfc(struct phy_device *phydev,
> > +                     struct ethtool_rxnfc *nfc);
> > +
> >  #endif /* _LINUX_BCM_PHY_LIB_H */
> > diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
> > index 3a627105675a..6c2212bd2779 100644
> > --- a/drivers/net/phy/broadcom.c
> > +++ b/drivers/net/phy/broadcom.c
> > @@ -1107,6 +1107,8 @@ static struct phy_driver broadcom_drivers[] = {
> >         .get_wol        = bcm54xx_phy_get_wol,
> >         .set_wol        = bcm54xx_phy_set_wol,
> >         .led_brightness_set     = bcm_phy_led_brightness_set,
> > +       .get_rxnfc      = bcm_phy_get_rxnfc,
> > +       .set_rxnfc      = bcm_phy_set_rxnfc,
> >  }, {
> >         .phy_id         = PHY_ID_BCM5461,
> >         .phy_id_mask    = 0xfffffff0,
> > --
> > 2.34.1
> >