diff --git a/hw/char/escc.c b/hw/char/escc.c index 0fce4f6324..a7d9050c83 100644 --- a/hw/char/escc.c +++ b/hw/char/escc.c @@ -354,6 +354,17 @@ static void escc_reset(DeviceState *d) cs->rregs[j] = 0; cs->wregs[j] = 0; } + + /* + * ...but there is an exception. The "Transmit Interrupts and Transmit + * Buffer Empty Bit" section on page 50 of the ESCC datasheet says of + * the STATUS_TXEMPTY bit in R_STATUS: "After a hardware reset + * (including a hardware reset by software), or a channel reset, this + * bit is set to 1". The Sun PROM checks this bit early on startup and + * gets stuck in an infinite loop if it is not set. + */ + cs->rregs[R_STATUS] |= STATUS_TXEMPTY; + escc_reset_chn(cs); } }