escc: reset register values to zero in escc_reset()

This is to ensure that a device reset always returns the ESCC to a known state.

Note that this is currently redundant with the same code in escc_reset_chn()
but that will change shortly.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210903113223.19551-3-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
This commit is contained in:
Mark Cave-Ayland 2021-09-03 12:32:16 +01:00
parent 0e042025b9
commit 9d248a4be5

View File

@ -300,9 +300,24 @@ static void escc_reset_chn(ESCCChannelState *s)
static void escc_reset(DeviceState *d)
{
ESCCState *s = ESCC(d);
int i, j;
escc_reset_chn(&s->chn[0]);
escc_reset_chn(&s->chn[1]);
for (i = 0; i < 2; i++) {
ESCCChannelState *cs = &s->chn[i];
/*
* According to the ESCC datasheet "Miscellaneous Questions" section
* on page 384, the values of the ESCC registers are not guaranteed on
* power-on until an explicit hardware or software reset has been
* issued. For now we zero the registers so that a device reset always
* returns the emulated device to a fixed state.
*/
for (j = 0; j < ESCC_SERIAL_REGS; j++) {
cs->rregs[j] = 0;
cs->wregs[j] = 0;
}
escc_reset_chn(cs);
}
}
static inline void set_rxint(ESCCChannelState *s)