perf(spmd): omit sel1 context save if sel2 present
The SPMC at S-EL2 manages S-EL1 execution contexts for SPs. The
currently running SP vCPU state is always saved when the SPMC exits to
SPMD. A fresh vCPU context is always restored when the SPMC is entered
from the SPMD and a SP resumed. For performance optimization reasons
this permits omitting the saving/restoring of the S-EL1 context from
within the EL3 SPMD on entering/exiting the SPMC. The S-EL2 SPMC and
NS-EL1 context save/restore remain done in the SPMD.
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I66413ed5983913791ff5c9fc03c590ee65c6ccd7
diff --git a/services/std_svc/spmd/spmd_main.c b/services/std_svc/spmd/spmd_main.c
index 06039f0..e18d94c 100644
--- a/services/std_svc/spmd/spmd_main.c
+++ b/services/std_svc/spmd/spmd_main.c
@@ -108,9 +108,10 @@
cm_set_context(&(spmc_ctx->cpu_ctx), SECURE);
/* Restore the context assigned above */
- cm_el1_sysregs_context_restore(SECURE);
#if SPMD_SPM_AT_SEL2
cm_el2_sysregs_context_restore(SECURE);
+#else
+ cm_el1_sysregs_context_restore(SECURE);
#endif
cm_set_next_eret_context(SECURE);
@@ -118,9 +119,10 @@
rc = spmd_spm_core_enter(&spmc_ctx->c_rt_ctx);
/* Save secure state */
- cm_el1_sysregs_context_save(SECURE);
#if SPMD_SPM_AT_SEL2
cm_el2_sysregs_context_save(SECURE);
+#else
+ cm_el1_sysregs_context_save(SECURE);
#endif
return rc;
@@ -346,15 +348,23 @@
unsigned int secure_state_out = (!secure_origin) ? SECURE : NON_SECURE;
/* Save incoming security state */
- cm_el1_sysregs_context_save(secure_state_in);
#if SPMD_SPM_AT_SEL2
+ if (secure_state_in == NON_SECURE) {
+ cm_el1_sysregs_context_save(secure_state_in);
+ }
cm_el2_sysregs_context_save(secure_state_in);
+#else
+ cm_el1_sysregs_context_save(secure_state_in);
#endif
/* Restore outgoing security state */
- cm_el1_sysregs_context_restore(secure_state_out);
#if SPMD_SPM_AT_SEL2
+ if (secure_state_out == NON_SECURE) {
+ cm_el1_sysregs_context_restore(secure_state_out);
+ }
cm_el2_sysregs_context_restore(secure_state_out);
+#else
+ cm_el1_sysregs_context_restore(secure_state_out);
#endif
cm_set_next_eret_context(secure_state_out);