This patch series enables support for PTP in AM65x SR1.0 devices.
This feature relies heavily on the Industrial Ethernet Peripheral
(IEP) hardware module, which implements a hardware counter through
which time is kept. This hardware block is the basis for exposing
a PTP hardware clock to userspace and for issuing timestamps for
incoming/outgoing packets, allowing for time synchronization.
The IEP also has compare registers that fire an interrupt when the
counter reaches the value stored in a compare register. This feature
allows us to support PPS events in the kernel.
The changes are separated into three patches:
- PATCH 01/03: Register SR1.0 devices with the IEP infrastructure to
expose a PHC clock to userspace, allowing time to be
adjusted using standard PTP tools. The code for issuing/
collecting packet timestamps is already present in the
current state of the driver, so only this needs to be
done.
- PATCH 02/03: Add support for IEP compare event/interrupt handling
to enable PPS events.
- PATCH 03/03: Add the interrupts to the IOT2050 device tree.
Currently every compare event generates two interrupts, the first
corresponding to the actual event and the second being a spurious
but otherwise harmless interrupt. The root cause of this has been
identified and has been solved in the platform's SDK. A forward port
of the SDK's patches also fixes the problem in upstream but is not
included here since it's upstreaming is out of the scope of this
series. If someone from TI would be willing to chime in and help
get the interrupt changes upstream that would be great!
Signed-off-by: Diogo Ivo <diogo.ivo@xxxxxxxxxxx>
---
Diogo Ivo (3):
net: ti: icssg-prueth: Enable PTP timestamping support for SR1.0 devices
net: ti: icss-iep: Enable compare events
arm64: dts: ti: iot2050: Add IEP interrupts for SR1.0 devices
.../boot/dts/ti/k3-am65-iot2050-common-pg1.dtsi | 12 ++++
drivers/net/ethernet/ti/icssg/icss_iep.c | 71 ++++++++++++++++++++++
drivers/net/ethernet/ti/icssg/icssg_prueth_sr1.c | 49 ++++++++++++++-
3 files changed, 131 insertions(+), 1 deletion(-)
---
base-commit: 2f0e3f6a6824dfda2759225326d9c69203c06bc8
change-id: 20240529-iep-8bb4a3cb9068
Best regards,
--
Diogo Ivo <diogo.ivo@xxxxxxxxxxx>
