SPI SWE: clear any pending boot-time interrupts in spi_init() Charger plug/unplug hw logic in the Iota ABB has no built-in debouncing, thus electrical contact bounce on the charging power connection interface produces a lot of charger plug/unplug interrupts. When we boot in charging mode (charging power present at boot time and is presumably the cause of Switch-ON), some bounce may occur between the initial Iota Switch-ON action and Calypso firmware booting. By clearing any accumulated ITSTATREG interrupts on boot, we prevent these pre-boot interrupts from generating charger plug/unplug events to FCHG, which would upset smooth from-boot charging.

/*
 * 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