This series introduces the MHI PHC (PTP Hardware Clock) driver, which
registers a PTP (Precision Time Protocol) clock and communicates with
the MHI core to get the device side timestamps. These timestamps are
then exposed to the PTP subsystem, enabling precise time synchronization
between the host and the device.
The device exposes these through MHI time sync capability registers.
The following diagram illustrates the architecture and data flow:
+-------------+ +--------------------+ +--------------+
|Userspace App|<-->|Kernel PTP framework|<-->|MHI PHC Driver|
+-------------+ +--------------------+ +--------------+
|
v
+-------------------------------+ +-----------------+
| MHI Device (Timestamp source) |<------->| MHI Core Driver |
+-------------------------------+ +-----------------+
- User space applications use the standard Linux PTP interface.
- The PTP subsystem routes IOCTLs to the MHI PHC driver.
- The MHI PHC driver communicates with the MHI core to fetch timestamps.
- The MHI core interacts with the device to retrieve accurate time data.
Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
---
Imran Shaik (1):
bus: mhi: host: mhi_phc: Add support for PHC over MHI
Krishna Chaitanya Chundru (3):
bus: mhi: host: Add support for 64bit register reads and writes
bus: mhi: pci_generic: Add support for 64 bit register read & write
bus: mhi: host: Update the Time sync logic to read 64 bit register value
Vivek Pernamitta (1):
bus: mhi: host: Add support for non-posted TSC timesync feature
drivers/bus/mhi/common.h | 4 +
drivers/bus/mhi/host/Kconfig | 8 ++
drivers/bus/mhi/host/Makefile | 1 +
drivers/bus/mhi/host/init.c | 28 +++++++
drivers/bus/mhi/host/internal.h | 9 +++
drivers/bus/mhi/host/main.c | 97 ++++++++++++++++++++++++
drivers/bus/mhi/host/mhi_phc.c | 150 +++++++++++++++++++++++++++++++++++++
drivers/bus/mhi/host/mhi_phc.h | 28 +++++++
drivers/bus/mhi/host/pci_generic.c | 46 ++++++++++++
include/linux/mhi.h | 43 +++++++++++
10 files changed, 414 insertions(+)
---
base-commit: 76dc04ffefccd3cbd8cfd160d8f3ca2667fd8dcb
change-id: 20250818-tsc_time_sync-dfe2c967d7b2
prerequisite-change-id: 20250818-mhi_cap-3b2bb05663f4:v5
prerequisite-patch-id: c19893c69b10f975a4f675273f4277030a429d2d
Best regards,
--
Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
