[ Upstream commit ee14cc9ea19ba9678177e2224a9c58cce5937c73 ]
Fix "double" clearing of interrupts, which can cause external events
or timestamps to be missed.
The E1000_TSIRC Time Sync Interrupt Cause register can be cleared in two
ways, by either reading it or by writing '1' into the specific cause
bit. This is documented in section 8.16.1.
The following flow was used:
1. read E1000_TSIRC into 'tsicr';
2. handle the interrupts present into 'tsirc' and mark them in 'ack';
3. write 'ack' into E1000_TSICR;
As both (1) and (3) will clear the interrupt cause, if the same
interrupt happens again between (1) and (3) it will be ignored,
causing events to be missed.
Remove the extra clear in (3).
Fixes: 00c65578b47b ("igb: enable internal PPS for the i210")
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cf99c1dd7b7729091043374b90807c7a5f9fd9b1 ]
Remove code duplication in the tsync interrupt handler function by moving
this logic to separate functions. This keeps the interrupt handler readable
and allows the new functions to be extended for adapter types other than
i210.
Signed-off-by: Ruud Bos <kernel.hbk@gmail.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Stable-dep-of: ee14cc9ea19b ("igb: Fix missing time sync events")
Signed-off-by: Sasha Levin <sashal@kernel.org>
