spi/fsl-espi: Don't spin forever on SPIE_RXCNT

Infinite loop on SPIE_RXCNT occurred.

while (SPIE_RXCNT(events) < min(4, mspi->len)) {
        cpu_relax();
        events = mpc8xxx_spi_read_reg(&reg_base->event);
}

We met a soft lockup at fsl_espi_cpu_irq() because of this.

Fix it by using spin_event_timeout() so that fsl_espi_cpu_irq()
can break loop with timeouts dmesg.

Signed-off-by: Nobuteru Hayashi <hayashi.nbb@ncos.nec.co.jp>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Nobuteru Hayashi 2016-03-18 11:35:21 +00:00 committed by Mark Brown
parent f55532a0c0
commit a12ddd60ed

View file

@ -539,11 +539,18 @@ void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
if (events & SPIE_NE) {
u32 rx_data, tmp;
u8 rx_data_8;
int ret;
/* Spin until RX is done */
while (SPIE_RXCNT(events) < min(4, mspi->len)) {
cpu_relax();
events = mpc8xxx_spi_read_reg(&reg_base->event);
if (SPIE_RXCNT(events) < min(4, mspi->len)) {
ret = spin_event_timeout(
!(SPIE_RXCNT(events =
mpc8xxx_spi_read_reg(&reg_base->event)) <
min(4, mspi->len)),
10000, 0); /* 10 msec */
if (!ret)
dev_err(mspi->dev,
"tired waiting for SPIE_RXCNT\n");
}
if (mspi->len >= 4) {