Rework BL3-1 unhandled exception handling and reporting

This patch implements the register reporting when unhandled exceptions are
taken in BL3-1. Unhandled exceptions will result in a dump of registers
to the console, before halting execution by that CPU. The Crash Stack,
previously called the Exception Stack, is used for this activity.
This stack is used to preserve the CPU context and runtime stack
contents for debugging and analysis.

This also introduces the per_cpu_ptr_cache, referenced by tpidr_el3,
to provide easy access to some of BL3-1 per-cpu data structures.
Initially, this is used to provide a pointer to the Crash stack.

panic() now prints the the error file and line number in Debug mode
and prints the PC value in release mode.

The Exception Stack is renamed to Crash Stack with this patch.
The original intention of exception stack is no longer valid
since we intend to support several valid exceptions like IRQ
and FIQ in the trusted firmware context. This stack is now
utilized for dumping and reporting the system state when a
crash happens and hence the rename.

Fixes ARM-software/tf-issues#79 Improve reporting of unhandled exception

Change-Id: I260791dc05536b78547412d147193cdccae7811a

1 files changed, 3 insertions, 1 deletions

diff --git a/include/bl31/context_mgmt.h b/include/bl31/context_mgmt.h
index efcdcd28..d2598eef 100644
--- a/include/bl31/context_mgmt.h
+++ b/include/bl31/context_mgmt.h
@@ -49,6 +49,8 @@ extern void cm_set_el3_eret_context(uint32_t security_state, uint64_t entrypoint
 		uint32_t spsr, uint32_t scr);
 extern void cm_set_el3_elr(uint32_t security_state, uint64_t entrypoint);
 extern void cm_set_next_eret_context(uint32_t security_state);
-extern void cm_init_exception_stack(uint64_t mpidr, uint32_t security_state);
+extern void cm_init_pcpu_ptr_cache();
+extern void cm_set_pcpu_ptr_cache(const void *pcpu_ptr);
+extern void *cm_get_pcpu_ptr_cache(void);
 
 #endif /* __CM_H__ */