Hi,
This series adds sysfs support to expose the PTM context available in the
capable PCIe controllers. Support for enabling PTM in the requester/responder is
already available in drivers/pci/pcie/ptm.c and this series expands that file to
add sysfs support for the PTM context info.
The controller drivers are expected to call pcie_ptm_create_sysfs() with
'pcie_ptm_ops' callbacks populated to create the sysfs entries and call
pcie_ptm_destroy_sysfs() to destroy them.
Patch 1 adds the necessary code in the drivers/pci/pcie/ptm.c to expose PTM
context over sysfs and patch 2 adds PTM support in the DWC drivers (host and
endpoint). Finally, patch 3 masks the PTM_UPDATING interrupt in the pcie-qcom-ep
driver to avoid processing the interrupt for each PTM context update.
Testing
=======
This series is tested on Qcom SA8775p Ride Mx platform where one SA8775p acts as
RC and another as EP with following instructions:
RC
--
$ echo 1 > /sys/devices/platform/1c10000.pcie/ptm/context_valid
EP
--
$ echo auto > /sys/devices/platform/1c10000.pcie-ep/ptm/context_update
$ cat /sys/devices/platform/1c10000.pcie-ep/ptm/local_clock
159612570424
$ cat /sys/devices/platform/1c10000.pcie-ep/ptm/master_clock
159609466232
$ cat /sys/devices/platform/1c10000.pcie-ep/ptm/t1
159609466112
$ cat /sys/devices/platform/1c10000.pcie-ep/ptm/t4
159609466518
NOTE: To make use of the PTM feature, the host PCIe client driver has to call
'pci_enable_ptm()' API during probe. This series was tested with enabling PTM in
the MHI host driver with a local change (which will be upstreamed later).
Technically, PTM could also be enabled in the pci_endpoint_test driver, but I
didn't add the change as I'm not sure we'd want to add random PCIe features in
the test driver without corresponding code in pci-epf-test driver.
Changes in v2:
* Dropped the VSEC changes that got merged
* Moved the PTM sysfs code from drivers/pci/controller/dwc to
drivers/pci/pcie/ptm to make it generic so that other controller drivers could
also benefit from it.
* Rebased on top of pci/controller/dwc
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
Manivannan Sadhasivam (3):
PCI: Add sysfs support for exposing PTM context
PCI: dwc: Add sysfs support for PTM context
PCI: qcom-ep: Mask PTM_UPDATING interrupt
Documentation/ABI/testing/sysfs-platform-pcie-ptm | 70 ++++++
MAINTAINERS | 1 +
drivers/pci/controller/dwc/Makefile | 2 +-
drivers/pci/controller/dwc/pcie-designware-ep.c | 3 +
drivers/pci/controller/dwc/pcie-designware-host.c | 3 +
drivers/pci/controller/dwc/pcie-designware-sysfs.c | 254 +++++++++++++++++++
drivers/pci/controller/dwc/pcie-designware.c | 6 +
drivers/pci/controller/dwc/pcie-designware.h | 21 ++
drivers/pci/controller/dwc/pcie-qcom-ep.c | 8 +
drivers/pci/pcie/ptm.c | 268 +++++++++++++++++++++
include/linux/pci.h | 35 +++
include/linux/pcie-dwc.h | 8 +
12 files changed, 678 insertions(+), 1 deletion(-)
---
base-commit: 1f5a69f1b3132054d8d82b8d7546d0af6a2ed4f6
change-id: 20250324-pcie-ptm-e75b9b2ffcfb
Best regards,
--
Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
