Remove coherent stack usage from the warm boot path
This patch uses stacks allocated in normal memory to enable the MMU early in the
warm boot path thus removing the dependency on stacks allocated in coherent
memory. Necessary cache and stack maintenance is performed when a cpu is being
powered down and up. This avoids any coherency issues that can arise from
reading speculatively fetched stale stack memory from another CPUs cache. These
changes affect the warm boot path in both BL3-1 and BL3-2.
The EL3 system registers responsible for preserving the MMU state are not saved
and restored any longer. Static values are used to program these system
registers when a cpu is powered on or resumed from suspend.
Change-Id: I8357e2eb5eb6c5f448492c5094b82b8927603784
diff --git a/services/std_svc/psci/psci_private.h b/services/std_svc/psci/psci_private.h
index 06db63f..b47bf85 100644
--- a/services/std_svc/psci/psci_private.h
+++ b/services/std_svc/psci/psci_private.h
@@ -128,5 +128,8 @@
int);
unsigned int psci_afflvl_suspend_finish(int, int);
+/* Private exported functions from psci_helpers.S */
+void psci_do_pwrdown_cache_maintenance(uint32_t affinity_level);
+void psci_do_pwrup_cache_maintenance(void);
#endif /* __PSCI_PRIVATE_H__ */