[RFC PATCH] net: macb: Process tx timestamp only on ptp packets

From: Harini Katakam
Date: Tue Aug 24 2021 - 06:12:54 EST


The current implementation timestamps all packets and also processes
the BD timestamp for the same. While it is true that HWTSTAMP_TX_ON
enables timestamps for outgoing packets, the sender of the packet
i.e. linuxptp enables timestamp for PTP or PTP event packets. Cadence
GEM IP has a provision to enable this in HW only for PTP packets.
Enable this option in DMA BD settings register to decrease overhead.

Signed-off-by: Harini Katakam <harini.katakam@xxxxxxxxxx>
Acked-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
---
drivers/net/ethernet/cadence/macb_ptp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c
index c2e1f163bb14..e4f26d972219 100644
--- a/drivers/net/ethernet/cadence/macb_ptp.c
+++ b/drivers/net/ethernet/cadence/macb_ptp.c
@@ -471,7 +471,7 @@ int gem_set_hwtst(struct net_device *dev, struct ifreq *ifr, int cmd)
return -ERANGE;
fallthrough;
case HWTSTAMP_TX_ON:
- tx_bd_control = TSTAMP_ALL_FRAMES;
+ tx_bd_control = TSTAMP_ALL_PTP_FRAMES;
break;
default:
return -ERANGE;
--
2.17.1