FreeCalypso > hg > fc-tourmaline
view src/cs/system/main/gcc/irq_twiddle.S @ 268:f2e52cab0a73
abb_inth.c: check all interrupt causes, not just one
The original code used if - else if - else if etc constructs, thus
the first detected interrupt was the only one handled. However,
Iota ITSTATREG is a clear-on-read register, thus if we only handle
the first detected interrupt and skip checking the others, then the
other interrupts will be lost, if more than one interrupt happened
to occur in one ABB interrupt handling cycle - a form of rare race
condition. Change the code to check all interrupts that were read
in this cycle.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Sun, 13 Jun 2021 18:17:53 +0000 |
| parents | 4e78acac3d88 |
| children |
line wrap: on
line source
/* * TI's L1 code (and possibly other parts of the software suite) calls * functions named INT_DisableIRQ() and INT_EnableIRQ(); in TI's original * fw they are implemented (in a very ugly manner, as usual) in the * int.s entry point assembly module. Here we implement the same * functions in a cleaner way. */ #include "asm_defs.h" .code 32 .text .globl INT_DisableIRQ INT_DisableIRQ: mrs r0, CPSR orr r0, r0, #LOCKOUT msr CPSR, r0 bx lr .globl INT_EnableIRQ INT_EnableIRQ: mrs r0, CPSR bic r0, r0, #LOCKOUT msr CPSR, r0 bx lr