Some EtherAVB variants support internal clock delay configuration, which
can add larger delays than the delays that are typically supported by
the PHY (using an "rgmii-*id" PHY mode, and/or "[rt]xc-skew-ps"
properties).
Historically, the EtherAVB driver configured these delays based on the
"rgmii-*id" PHY mode. This caused issues with PHY drivers that
implement PHY internal delays properly[1]. Hence a backwards-compatible
workaround was added by masking the PHY mode[2].
Add proper support for explicit configuration of the MAC internal clock
delays using the new "[rt]x-internal-delay-ps" properties.
Fall back to the old handling if none of these properties is present.
[1] Commit bcf3440c6dd78bfe ("net: phy: micrel: add phy-mode support for
the KSZ9031 PHY")
[2] Commit 9b23203c32ee02cd ("ravb: Mask PHY mode to avoid inserting
delays twice").
Signed-off-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Sergei Shtylyov <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
---
v4:
- Add Reviewed-by,
v3:
- No changes,
v2:
- Add Reviewed-by,
- Split long line,
- Replace "renesas,[rt]xc-delay-ps" by "[rt]x-internal-delay-ps",
- Use 1 instead of true when assigning to a single-bit bitfield.
---
drivers/net/ethernet/renesas/ravb.h | 1 +
drivers/net/ethernet/renesas/ravb_main.c | 36 ++++++++++++++++++------
2 files changed, 28 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index e5ca12ce93c730a9..7453b17a37a2c8d0 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -1038,6 +1038,7 @@ struct ravb_private {
unsigned wol_enabled:1;
unsigned rxcidm:1; /* RX Clock Internal Delay Mode */
unsigned txcidm:1; /* TX Clock Internal Delay Mode */
+ unsigned rgmii_override:1; /* Deprecated rgmii-*id behavior */
int num_tx_desc; /* TX descriptors per packet */
};
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 59dadd971345e0d1..aa120e3f1e4d4da5 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -1034,11 +1034,8 @@ static int ravb_phy_init(struct net_device *ndev)
pn = of_node_get(np);
}
- iface = priv->phy_interface;
- if (priv->chip_id != RCAR_GEN2 && phy_interface_mode_is_rgmii(iface)) {
- /* ravb_set_delay_mode() takes care of internal delay mode */
- iface = PHY_INTERFACE_MODE_RGMII;
- }
+ iface = priv->rgmii_override ? PHY_INTERFACE_MODE_RGMII
+ : priv->phy_interface;
phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0, iface);
of_node_put(pn);
if (!phydev) {
@@ -1989,20 +1986,41 @@ static const struct soc_device_attribute ravb_delay_mode_quirk_match[] = {
};
/* Set tx and rx clock internal delay modes */
-static void ravb_parse_delay_mode(struct net_device *ndev)
+static void ravb_parse_delay_mode(struct device_node *np, struct net_device *ndev)
{
struct ravb_private *priv = netdev_priv(ndev);
+ bool explicit_delay = false;
+ u32 delay;
+
+ if (!of_property_read_u32(np, "rx-internal-delay-ps", &delay)) {
+ /* Valid values are 0 and 1800, according to DT bindings */
+ priv->rxcidm = !!delay;
+ explicit_delay = true;
+ }
+ if (!of_property_read_u32(np, "tx-internal-delay-ps", &delay)) {
+ /* Valid values are 0 and 2000, according to DT bindings */
+ priv->txcidm = !!delay;
+ explicit_delay = true;
+ }
+ if (explicit_delay)
+ return;
+
+ /* Fall back to legacy rgmii-*id behavior */
if (priv->phy_interface == PHY_INTERFACE_MODE_RGMII_ID ||
- priv->phy_interface == PHY_INTERFACE_MODE_RGMII_RXID)
+ priv->phy_interface == PHY_INTERFACE_MODE_RGMII_RXID) {
priv->rxcidm = 1;
+ priv->rgmii_override = 1;
+ }
if (priv->phy_interface == PHY_INTERFACE_MODE_RGMII_ID ||
priv->phy_interface == PHY_INTERFACE_MODE_RGMII_TXID) {
if (!WARN(soc_device_match(ravb_delay_mode_quirk_match),
"phy-mode %s requires TX clock internal delay mode which is not supported by this hardware revision. Please update device tree",
- phy_modes(priv->phy_interface)))
+ phy_modes(priv->phy_interface))) {
priv->txcidm = 1;
+ priv->rgmii_override = 1;
+ }
}
}
@@ -2148,7 +2166,7 @@ static int ravb_probe(struct platform_device *pdev)
ravb_modify(ndev, GCCR, GCCR_LTI, GCCR_LTI);
if (priv->chip_id != RCAR_GEN2) {
- ravb_parse_delay_mode(ndev);
+ ravb_parse_delay_mode(np, ndev);
ravb_set_delay_mode(ndev);
}
--
2.17.1
Geert
On 9/17/20 8:57 AM, Geert Uytterhoeven wrote:
> Some EtherAVB variants support internal clock delay configuration, which
> can add larger delays than the delays that are typically supported by
> the PHY (using an "rgmii-*id" PHY mode, and/or "[rt]xc-skew-ps"
> properties).
>
> Historically, the EtherAVB driver configured these delays based on the
> "rgmii-*id" PHY mode. This caused issues with PHY drivers that
> implement PHY internal delays properly[1]. Hence a backwards-compatible
> workaround was added by masking the PHY mode[2].
>
> Add proper support for explicit configuration of the MAC internal clock
> delays using the new "[rt]x-internal-delay-ps" properties.
> Fall back to the old handling if none of these properties is present.
>
> [1] Commit bcf3440c6dd78bfe ("net: phy: micrel: add phy-mode support for
> the KSZ9031 PHY")
> [2] Commit 9b23203c32ee02cd ("ravb: Mask PHY mode to avoid inserting
> delays twice").
>
> Signed-off-by: Geert Uytterhoeven <[email protected]>
> Reviewed-by: Sergei Shtylyov <[email protected]>
> Reviewed-by: Florian Fainelli <[email protected]>
> ---
> v4:
> - Add Reviewed-by,
>
> v3:
> - No changes,
>
> v2:
> - Add Reviewed-by,
> - Split long line,
> - Replace "renesas,[rt]xc-delay-ps" by "[rt]x-internal-delay-ps",
> - Use 1 instead of true when assigning to a single-bit bitfield.
> ---
> drivers/net/ethernet/renesas/ravb.h | 1 +
> drivers/net/ethernet/renesas/ravb_main.c | 36 ++++++++++++++++++------
> 2 files changed, 28 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
> index e5ca12ce93c730a9..7453b17a37a2c8d0 100644
> --- a/drivers/net/ethernet/renesas/ravb.h
> +++ b/drivers/net/ethernet/renesas/ravb.h
> @@ -1038,6 +1038,7 @@ struct ravb_private {
> unsigned wol_enabled:1;
> unsigned rxcidm:1; /* RX Clock Internal Delay Mode */
> unsigned txcidm:1; /* TX Clock Internal Delay Mode */
> + unsigned rgmii_override:1; /* Deprecated rgmii-*id behavior */
> int num_tx_desc; /* TX descriptors per packet */
> };
>
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 59dadd971345e0d1..aa120e3f1e4d4da5 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -1034,11 +1034,8 @@ static int ravb_phy_init(struct net_device *ndev)
> pn = of_node_get(np);
> }
>
> - iface = priv->phy_interface;
> - if (priv->chip_id != RCAR_GEN2 && phy_interface_mode_is_rgmii(iface)) {
> - /* ravb_set_delay_mode() takes care of internal delay mode */
> - iface = PHY_INTERFACE_MODE_RGMII;
> - }
> + iface = priv->rgmii_override ? PHY_INTERFACE_MODE_RGMII
> + : priv->phy_interface;
> phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0, iface);
> of_node_put(pn);
> if (!phydev) {
> @@ -1989,20 +1986,41 @@ static const struct soc_device_attribute ravb_delay_mode_quirk_match[] = {
> };
>
> /* Set tx and rx clock internal delay modes */
> -static void ravb_parse_delay_mode(struct net_device *ndev)
> +static void ravb_parse_delay_mode(struct device_node *np, struct net_device *ndev)
> {
> struct ravb_private *priv = netdev_priv(ndev);
> + bool explicit_delay = false;
> + u32 delay;
> +
> + if (!of_property_read_u32(np, "rx-internal-delay-ps", &delay)) {
> + /* Valid values are 0 and 1800, according to DT bindings */
> + priv->rxcidm = !!delay;
> + explicit_delay = true;
> + }
> + if (!of_property_read_u32(np, "tx-internal-delay-ps", &delay)) {
> + /* Valid values are 0 and 2000, according to DT bindings */
> + priv->txcidm = !!delay;
> + explicit_delay = true;
> + }
There are helper functions for this
s32 phy_get_internal_delay(struct phy_device *phydev, struct device
*dev, const int *delay_values, int size, bool is_rx)
Hi Dan,
On Thu, Sep 17, 2020 at 8:50 PM Dan Murphy <[email protected]> wrote:
> On 9/17/20 8:57 AM, Geert Uytterhoeven wrote:
> > Some EtherAVB variants support internal clock delay configuration, which
> > can add larger delays than the delays that are typically supported by
> > the PHY (using an "rgmii-*id" PHY mode, and/or "[rt]xc-skew-ps"
> > properties).
> >
> > Historically, the EtherAVB driver configured these delays based on the
> > "rgmii-*id" PHY mode. This caused issues with PHY drivers that
> > implement PHY internal delays properly[1]. Hence a backwards-compatible
> > workaround was added by masking the PHY mode[2].
> >
> > Add proper support for explicit configuration of the MAC internal clock
> > delays using the new "[rt]x-internal-delay-ps" properties.
> > Fall back to the old handling if none of these properties is present.
> >
> > [1] Commit bcf3440c6dd78bfe ("net: phy: micrel: add phy-mode support for
> > the KSZ9031 PHY")
> > [2] Commit 9b23203c32ee02cd ("ravb: Mask PHY mode to avoid inserting
> > delays twice").
> >
> > Signed-off-by: Geert Uytterhoeven <[email protected]>
> > Reviewed-by: Sergei Shtylyov <[email protected]>
> > Reviewed-by: Florian Fainelli <[email protected]>
> > @@ -1989,20 +1986,41 @@ static const struct soc_device_attribute ravb_delay_mode_quirk_match[] = {
> > };
> >
> > /* Set tx and rx clock internal delay modes */
> > -static void ravb_parse_delay_mode(struct net_device *ndev)
> > +static void ravb_parse_delay_mode(struct device_node *np, struct net_device *ndev)
> > {
> > struct ravb_private *priv = netdev_priv(ndev);
> > + bool explicit_delay = false;
> > + u32 delay;
> > +
> > + if (!of_property_read_u32(np, "rx-internal-delay-ps", &delay)) {
> > + /* Valid values are 0 and 1800, according to DT bindings */
> > + priv->rxcidm = !!delay;
> > + explicit_delay = true;
> > + }
> > + if (!of_property_read_u32(np, "tx-internal-delay-ps", &delay)) {
> > + /* Valid values are 0 and 2000, according to DT bindings */
> > + priv->txcidm = !!delay;
> > + explicit_delay = true;
> > + }
> There are helper functions for this
>
> s32 phy_get_internal_delay(struct phy_device *phydev, struct device
> *dev, const int *delay_values, int size, bool is_rx)
That helper operates on the PHY device, not on the MAC device.
Cfr. what I stated in the cover letter:
This can be considered the MAC counterpart of commit 9150069bf5fc0e86
("dt-bindings: net: Add tx and rx internal delays"), which applies to
the PHY. Note that unlike commit 92252eec913b2dd5 ("net: phy: Add a
helper to return the index for of the internal delay"), no helpers are
provided to parse the DT properties, as so far there is a single user
only, which supports only zero or a single fixed value. Of course such
helpers can be added later, when the need arises, or when deemed useful
otherwise.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds