[PATCH 2/9] common/sfc_efx/base: fix flow control setting on legacy MCDI

Ivan Malov
2025-12-29T21:35:50Z

On X2 adaptors, tests have shown a mismatch between the mode the user asks
for and the resulting one, given the partner is set to use autonegotiation.
For example, asking for 'RX_PAUSE' results in 'FULL' being actually in use.

As per 'SET_MAC' MCDI documentation (in 'efx_regs_mcdi.h'), it is wrong to
set 'FCNTL' field to 'AUTO' when the user wants a fixed mode. Correct this.

Fixes: e7cd430c864f ("net/sfc/base: import SFN7xxx family support")
Cc: stable@dpdk.org

Signed-off-by: Ivan Malov <ivan.malov@arknetworks.am>
Reviewed-by: Andy Moreton <andy.moreton@amd.com>
---
drivers/common/sfc_efx/base/ef10_mac.c | 35 ++++++++++++++++++++------
1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/drivers/common/sfc_efx/base/ef10_mac.c b/drivers/common/sfc_efx/base/ef10_mac.c
index bfc82b80c7..016bd88774 100644
--- a/drivers/common/sfc_efx/base/ef10_mac.c
+++ b/drivers/common/sfc_efx/base/ef10_mac.c
@@ -273,6 +273,7 @@ ef10_mac_reconfigure(
efx_mcdi_req_t req;
EFX_MCDI_DECLARE_BUF(payload, MC_CMD_SET_MAC_IN_LEN,
MC_CMD_SET_MAC_OUT_LEN);
+ uint32_t fcntl;
efx_rc_t rc;

req.emr_cmd = MC_CMD_SET_MAC;
@@ -299,13 +300,29 @@ ef10_mac_reconfigure(
SET_MAC_IN_REJECT_UNCST, 0,
SET_MAC_IN_REJECT_BRDCST, 0);

- /*
- * Flow control, whether it is auto-negotiated or not,
- * is set via the PHY advertised capabilities. When set to
- * automatic the MAC will use the PHY settings to determine
- * the flow control settings.
- */
- MCDI_IN_SET_DWORD(req, SET_MAC_IN_FCNTL, MC_CMD_FCNTL_AUTO);
+ if (epp->ep_fcntl_autoneg != B_FALSE) {
+ fcntl = MC_CMD_FCNTL_AUTO;
+ } else {
+ switch (epp->ep_fcntl) {
+ case 0:
+ fcntl = MC_CMD_FCNTL_OFF;
+ break;
+ case EFX_FCNTL_RESPOND:
+ fcntl = MC_CMD_FCNTL_RESPOND;
+ break;
+ case EFX_FCNTL_GENERATE:
+ fcntl = MC_CMD_FCNTL_GENERATE;
+ break;
+ case EFX_FCNTL_RESPOND | EFX_FCNTL_GENERATE:
+ fcntl = MC_CMD_FCNTL_BIDIR;
+ break;
+ default:
+ rc = EINVAL;
+ goto fail1;
+ }
+ }
+
+ MCDI_IN_SET_DWORD(req, SET_MAC_IN_FCNTL, fcntl);

/* Include the Ethernet frame checksum in RX packets if it's required */
MCDI_IN_POPULATE_DWORD_1(req, SET_MAC_IN_FLAGS,
@@ -321,7 +338,7 @@ ef10_mac_reconfigure(
*/
if (req.emr_rc != EACCES) {
rc = req.emr_rc;
- goto fail1;
+ goto fail2;
}
}

@@ -338,6 +355,8 @@ ef10_mac_reconfigure(

return (0);

+fail2:
+ EFSYS_PROBE(fail2);
fail1:
EFSYS_PROBE1(fail1, efx_rc_t, rc);

--
2.47.3