diff mbox series

[net,v2,1/5] igb: reject invalid external timestamp requests for 82580-based HW

Message ID 20250312-jk-net-fixes-supported-extts-flags-v2-1-ea930ba82459@intel.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: ptp: fix egregious supported flag checks | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 10 of 10 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 12 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 5 this patch: 5
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-03-13--00-00 (tests: 894)

Commit Message

Jacob Keller March 12, 2025, 10:15 p.m. UTC
The igb_ptp_feature_enable_82580 function correctly checks that unknown
flags are not passed to the function. However, it does not actually check
PTP_RISING_EDGE or PTP_FALLING_EDGE when configuring the external timestamp
function.

The data sheet for the 82580 product says:

  Upon a change in the input level of one of the SDP pins that was
  configured to detect Time stamp events using the TSSDP register, a time
  stamp of the system time is captured into one of the two auxiliary time
  stamp registers (AUXSTMPL/H0 or AUXSTMPL/H1).

  For example to define timestamping of events in the AUXSTMPL0 and
  AUXSTMPH0 registers, Software should:

  1. Set the TSSDP.AUX0_SDP_SEL field to select the SDP pin that detects
     the level change and set the TSSDP.AUX0_TS_SDP_EN bit to 1.

  2. Set the TSAUXC.EN_TS0 bit to 1 to enable timestamping

The same paragraph is in the i350 and i354 data sheets.

The wording implies that the time stamps are captured at any level change.
There does not appear to be any way to only timestamp one edge of the
signal.

Reject requests which do not set both PTP_RISING_EDGE and PTP_FALLING_EDGE
when operating under PTP_STRICT_FLAGS mode via PTP_EXTTS_REQUEST2.

Fixes: 38970eac41db ("igb: support EXTTS on 82580/i354/i350")
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
Changes in v2:
- Fix the 82580 check to allow disabling the pin without flags set.
---
 drivers/net/ethernet/intel/igb/igb_ptp.c | 6 ++++++
 1 file changed, 6 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c
index f9457055612004c10f74379122063e8136fe7d76..f323e1c1989f1bfbbf1f04043c2c0f14ae8c716f 100644
--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -509,6 +509,12 @@  static int igb_ptp_feature_enable_82580(struct ptp_clock_info *ptp,
 					PTP_STRICT_FLAGS))
 			return -EOPNOTSUPP;
 
+		/* Both the rising and falling edge are timestamped */
+		if (rq->extts.flags & PTP_STRICT_FLAGS &&
+		    (rq->extts.flags & PTP_ENABLE_FEATURE) &&
+		    (rq->extts.flags & PTP_EXTTS_EDGES) != PTP_EXTTS_EDGES)
+			return -EOPNOTSUPP;
+
 		if (on) {
 			pin = ptp_find_pin(igb->ptp_clock, PTP_PF_EXTTS,
 					   rq->extts.index);