Changeset 8bac485 in rtems for c/src/lib/libcpu/powerpc/new-exceptions/bspsupport/ppc_exc_hdl.c

2008-07-10 Till Straumann <strauman@…>

• new-exceptions/bspsupport/ppc_exc_asm_macros.S, new-exceptions/bspsupport/ppc_exc_bspsupp.h, new-exceptions/bspsupport/ppc_exc_hdl.c, new-exceptions/bspsupport/vectors_init.c: fixed and enabled stack-switching algorithm which figures out if we already run on the ISR stack rather than relying on the _ISR_Nest_level.

Added 'ppc_exc_crit_always_enabled' variable which defines
the semantics of critical interrupts. Added a test to
TEST_LOCK_crit so that calling ppc_exc_wrapup() (and
possibly the dispatcher) is always skipped if the BSP/user
wants to leave critical interrupts always enabled (at the
expense of having no OS support).

changed TEST_LOCK_mchk so that asynchronous machine-check
handlers never call ppc_exc_wrapup() (and the dispatcher).
We don't want to disable MSR_ME ever (to avoid checkstops)
and hence asynchronous MEs must not use OS services anyways.

added and commented new variables 'ppc_exc_intr_stack_size'
'ppc_exc_crit_always_enabled'.