tree df15b6e75c7b94ea96b7840fa654229350412fe3
parent bd63482aac3e04832ac4cc9e0f9a69b6750bac75
author Wing Li <wingers@google.com> 1683214279 -0700
committer Wing Li <wingers@google.com> 1685602459 -0700

fix(psci): add optional pwr_domain_validate_suspend to plat_psci_ops_t

This patch adds a new optional member `pwr_domain_validate_suspend` to
the `plat_psci_ops_t` structure that allows a platform to optionally
perform platform specific validations in OS-initiated mode. This is
conditionally compiled into the build depending on the value of the
`PSCI_OS_INIT_MODE` build option.

In https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/17682,
the return type of the `pwr_domain_suspend` handler was updated from
`void` to `int` to allow a platform to optionally perform platform
specific validations in OS-initiated mode. However, when an error code
other than `PSCI_E_SUCCESS` is returned, the current exit path does not
undo the operations in `psci_suspend_to_pwrdown_start`, and as a result,
the system ends up in an unexpected state.

The fix in this patch prevents the need to undo the operations in
`psci_suspend_to_pwrdown_start`, by allowing the platform to first
perform any necessary platform specific validations before the PSCI
generic code proceeds to the point of no return where the CPU_SUSPEND
request is expected to complete successfully.

Change-Id: I05d92c7ea3f5364da09af630d44d78252185db20
Signed-off-by: Wing Li <wingers@google.com>