forked from Imagelibrary/rtems
8bac4851a6
* 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'.