[PATCH resubmit 2] net: fec: Fix FEC_ECR_EN1588 being cleared on link-down

From: Csókás, Bence
Date: Tue Jun 11 2024 - 04:05:36 EST


FEC_ECR_EN1588 bit gets cleared after MAC reset in `fec_stop()`, which
makes all 1588 functionality shut down, and all the extended registers
disappear, on link-down, making the adapter fall back to compatibility
"dumb mode". However, some functionality needs to be retained (e.g. PPS)
even without link.

Fixes: 6605b730c061 ("FEC: Add time stamping code and a PTP hardware clock")
Cc: Richard Cochran <richardcochran@xxxxxxxxx>

Signed-off-by: Csókás, Bence <csokas.bence@xxxxxxxxx>
---
drivers/net/ethernet/freescale/fec_main.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 881ece735dcf..fb19295529a2 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1361,6 +1361,12 @@ fec_stop(struct net_device *ndev)
writel(FEC_ECR_ETHEREN, fep->hwp + FEC_ECNTRL);
writel(rmii_mode, fep->hwp + FEC_R_CNTRL);
}
+
+ if (fep->bufdesc_ex) {
+ val = readl(fep->hwp + FEC_ECNTRL);
+ val |= FEC_ECR_EN1588;
+ writel(val, fep->hwp + FEC_ECNTRL);
+ }
}

static void
--
2.34.1