[PATCH 1/2] net: qcom/emac: configure the external phy to allow pause frames

[Timur Tabi]

Pause frames are used to enable flow control.  A MAC can send and
receive pause frames in order to throttle traffic.  However, the PHY
must be configured to allow those frames to pass through.

Reviewed-by: Florian Fainelli 
Signed-off-by: Timur Tabi 
---
 drivers/net/ethernet/qualcomm/emac/emac-mac.c | 6 ++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-mac.c 
b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
index 6fb3bee..70a55dc 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -1003,6 +1003,12 @@ int emac_mac_up(struct emac_adapter *adpt)
writel((u32)~DIS_INT, adpt->base + EMAC_INT_STATUS);
writel(adpt->irq.mask, adpt->base + EMAC_INT_MASK);
 
+   /* Enable pause frames.  Without this feature, the EMAC has been shown
+* to receive (and drop) frames with FCS errors at gigabit connections.
+*/
+   adpt->phydev->supported |= SUPPORTED_Pause | SUPPORTED_Asym_Pause;
+   adpt->phydev->advertising |= SUPPORTED_Pause | SUPPORTED_Asym_Pause;
+
adpt->phydev->irq = PHY_IGNORE_INTERRUPT;
phy_start(adpt->phydev);
 
-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH 1/2] net: qcom/emac: configure the external phy to allow pause frames

[Timur Tabi]

Timur Tabi wrote:

Pause frames are used to enable flow control.  A MAC can send and
receive pause frames in order to throttle traffic.  However, the PHY
must be configured to allow those frames to pass through.

Signed-off-by: Timur Tabi 


Ugh, I forgot to include an introductory post.  Coming right up.


--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

Re: [PATCH 1/2] net: qcom/emac: configure the external phy to allow pause frames

[Florian Fainelli]

On 11/01/2016 11:30 AM, Timur Tabi wrote:
> Pause frames are used to enable flow control.  A MAC can send and
> receive pause frames in order to throttle traffic.  However, the PHY
> must be configured to allow those frames to pass through.
> 
> Signed-off-by: Timur Tabi 

Reviewed-by: Florian Fainelli 
-- 
Florian

[PATCH 1/2] net: qcom/emac: configure the external phy to allow pause frames

[Timur Tabi]

Pause frames are used to enable flow control.  A MAC can send and
receive pause frames in order to throttle traffic.  However, the PHY
must be configured to allow those frames to pass through.

Signed-off-by: Timur Tabi 
---
 drivers/net/ethernet/qualcomm/emac/emac-mac.c | 6 ++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-mac.c 
b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
index 6fb3bee..70a55dc 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -1003,6 +1003,12 @@ int emac_mac_up(struct emac_adapter *adpt)
writel((u32)~DIS_INT, adpt->base + EMAC_INT_STATUS);
writel(adpt->irq.mask, adpt->base + EMAC_INT_MASK);
 
+   /* Enable pause frames.  Without this feature, the EMAC has been shown
+* to receive (and drop) frames with FCS errors at gigabit connections.
+*/
+   adpt->phydev->supported |= SUPPORTED_Pause | SUPPORTED_Asym_Pause;
+   adpt->phydev->advertising |= SUPPORTED_Pause | SUPPORTED_Asym_Pause;
+
adpt->phydev->irq = PHY_IGNORE_INTERRUPT;
phy_start(adpt->phydev);
 
-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.