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

[Timur Tabi <timur@codeaurora.org>]

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 <f.fainelli@gmail.com>
Signed-off-by: Timur Tabi <timur@codeaurora.org>
---
 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.