[PATCH v2 4/9] escc: introduce escc_hard_reset_chn() for hardware reset

[Mark Cave-Ayland]

This new hardware reset function is to be called for both channels when the
hardware reset bit is written to register WR9. Its initial implementation is
the same as the existing escc_reset_chn() function used for device reset.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 hw/char/escc.c | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/hw/char/escc.c b/hw/char/escc.c
index 935ec1aef6..691086d97d 100644
--- a/hw/char/escc.c
+++ b/hw/char/escc.c
@@ -331,6 +331,40 @@ static void escc_soft_reset_chn(ESCCChannelState *s)
     clear_queue(s);
 }
 
+static void escc_hard_reset_chn(ESCCChannelState *s)
+{
+    int i;
+
+    s->reg = 0;
+    for (i = 0; i < ESCC_SERIAL_REGS; i++) {
+        s->rregs[i] = 0;
+        s->wregs[i] = 0;
+    }
+    /* 1X divisor, 1 stop bit, no parity */
+    s->wregs[W_TXCTRL1] = TXCTRL1_1STOP;
+    s->wregs[W_MINTR] = MINTR_RST_ALL;
+    /* Synch mode tx clock = TRxC */
+    s->wregs[W_CLOCK] = CLOCK_TRXC;
+    /* PLL disabled */
+    s->wregs[W_MISC2] = MISC2_PLLDIS;
+    /* Enable most interrupts */
+    s->wregs[W_EXTINT] = EXTINT_DCD | EXTINT_SYNCINT | EXTINT_CTSINT |
+                         EXTINT_TXUNDRN | EXTINT_BRKINT;
+    if (s->disabled) {
+        s->rregs[R_STATUS] = STATUS_TXEMPTY | STATUS_DCD | STATUS_SYNC |
+                             STATUS_CTS | STATUS_TXUNDRN;
+    } else {
+        s->rregs[R_STATUS] = STATUS_TXEMPTY | STATUS_TXUNDRN;
+    }
+    s->rregs[R_SPEC] = SPEC_BITS8 | SPEC_ALLSENT;
+
+    s->rx = s->tx = 0;
+    s->rxint = s->txint = 0;
+    s->rxint_under_svc = s->txint_under_svc = 0;
+    s->e0_mode = s->led_mode = s->caps_lock_mode = s->num_lock_mode = 0;
+    clear_queue(s);
+}
+
 static void escc_reset(DeviceState *d)
 {
     ESCCState *s = ESCC(d);
@@ -587,7 +621,8 @@ static void escc_mem_write(void *opaque, hwaddr addr,
                 escc_soft_reset_chn(&serial->chn[1]);
                 return;
             case MINTR_RST_ALL:
-                escc_reset(DEVICE(serial));
+                escc_hard_reset_chn(&serial->chn[0]);
+                escc_hard_reset_chn(&serial->chn[1]);
                 return;
             }
             break;
-- 
2.20.1