[PATCH v3 0/3] Polling for MHI ready

From: Bhaumik Bhatt
Date: Tue Feb 23 2021 - 22:45:41 EST


v3:
-Removed config changes that crept in in the first patch

v2:
-Addressed review comments
-Introduce new patch for to use controller defined read_reg() for polling
-Add usage in RDDM download panic path as well

Use polling instead of interrupt driven approach to wait for MHI ready state.

In certain devices, it is likely that there is no incoming MHI
interrupt for a transition to MHI READY state. One such example
is the move from Pass Through to an SBL or AMSS execution
environment. In order to facilitate faster bootup times as there
is no need to wait until timeout_ms completes, MHI host can poll
every 25 milliseconds to check if device has entered MHI READY
until a maximum timeout of twice the timeout_ms is reached.

This patch series has been tested on an arm64 device.

Bhaumik Bhatt (3):
bus: mhi: core: Introduce internal register poll helper function
bus: mhi: core: Move to polling method to wait for MHI ready
bus: mhi: core: Use poll register read API for RDDM download

drivers/bus/mhi/core/boot.c | 20 ++++++--------------
drivers/bus/mhi/core/internal.h | 3 +++
drivers/bus/mhi/core/main.c | 23 +++++++++++++++++++++++
drivers/bus/mhi/core/pm.c | 31 ++++++++++++++-----------------
4 files changed, 46 insertions(+), 31 deletions(-)

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