arm-trusted-firmware/services/spd
Soby Mathew 63b8440fcc TSP: Allow preemption of synchronous S-EL1 interrupt handling
Earlier the TSP only ever expected to be preempted during Standard SMC
processing. If a S-EL1 interrupt triggered while in the normal world, it
will routed to S-EL1 `synchronously` for handling. The `synchronous` S-EL1
interrupt handler `tsp_sel1_intr_entry` used to panic if this S-EL1 interrupt
was preempted by another higher priority pending interrupt which should be
handled in EL3 e.g. Group0 interrupt in GICv3.

With this patch, the `tsp_sel1_intr_entry` now expects `TSP_PREEMPTED` as the
return code from the `tsp_common_int_handler` in addition to 0 (interrupt
successfully handled) and in both cases it issues an SMC with id
`TSP_HANDLED_S_EL1_INTR`. The TSPD switches the context and returns back
to normal world. In case a higher priority EL3 interrupt was pending, the
execution will be routed to EL3 where interrupt will be handled. On return
back to normal world, the pending S-EL1 interrupt which was preempted will
get routed to S-EL1 to be handled `synchronously` via `tsp_sel1_intr_entry`.

Change-Id: I2087c7fedb37746fbd9200cdda9b6dba93e16201
2015-12-09 09:58:17 +00:00
..
opteed Remove the IMF_READ_INTERRUPT_ID build option 2015-11-26 17:07:32 +00:00
tlkd TLKD: pass results with TLK_RESUME_FID function ID 2015-10-09 22:22:56 +05:30
tspd TSP: Allow preemption of synchronous S-EL1 interrupt handling 2015-12-09 09:58:17 +00:00