SPM: Maintain NS caller FP state
APCS based function call makes the SPM execution state returned
to the caller. Most of the state change does not matter such as
arithmetic flags recorded in 'xPSR', but the float-point state
matters because it affects the float-point context stacking. When
NSPE without float-point enabled gets the float-points state
returned from SPE, the subsequent context stacking would fail.
This patch maintains the NS states when calling SPM functions. Also
explains why TF-M veneer is written in the assembly in the comments.
Change-Id: I719658f4240630271d2b8bee54431b6538930536
Signed-off-by: Ken Liu <Ken.Liu@arm.com>
1 file changed