2021-06-19 07:12:43

by Bhaumik Bhatt

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Subject: [PATCH v2] MHI event ring priority updates

Event ring priorities have remained out of use and are set to 1 by default.
This series brings about an enum entry expanding use of the priority field by
adding high priority tasklet scheduling to the menu.

In some cases, tasklet scheduling delays can be a nuisance. An example would be
ath11k adding a610f3c65d3b ("bus: mhi: Wait for M2 state during system resume")
in response to it. This issue can be potentially avoided if the controller uses
a dedicated event ring for control packets with high priority tasklet scheduling
in place.

There are no functional changes added to the controller (pci_generic or ath11k)
drivers with this series and the only changes there are use of the enum in place
of a harcoded value of "1". In the future, controllers can opt in to have any
event ring scheduled in high priority.

Tested on: X86_64 architecture with SDX65 on Ubuntu 18.04 distribution.

v2:
-Remove enum and update kernel doc for priority simplifying the implementation
-Drop patches for controller changes as they become unnecessary
-Merge adding and enabling of support patches

Hemant Kumar (1):
bus: mhi: core: Add support for processing priority of event ring

drivers/bus/mhi/core/init.c | 3 +--
drivers/bus/mhi/core/main.c | 9 +++++++--
include/linux/mhi.h | 2 +-
3 files changed, 9 insertions(+), 5 deletions(-)

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