diff mbox series

[v3,3/9] escc: introduce escc_soft_reset_chn() for software reset

Message ID 20210903113223.19551-4-mark.cave-ayland@ilande.co.uk
State New
Headers show
Series escc: fix reset and R_STATUS when SDLC mode is enabled | expand

Commit Message

Mark Cave-Ayland Sept. 3, 2021, 11:32 a.m. UTC
This new software reset function is to be called when the appropriate channel
software reset bit is written to register WR9. Its initial implementation is
the same as the existing escc_reset_chn() function used for device reset.

Add a new trace event when the guest initiates a soft reset via the WR9 register
to help diagnose guest reset issues.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 hw/char/escc.c       | 40 ++++++++++++++++++++++++++++++++++++++--
 hw/char/trace-events |  1 +
 2 files changed, 39 insertions(+), 2 deletions(-)

Comments

Peter Maydell Sept. 7, 2021, 1 p.m. UTC | #1
On Fri, 3 Sept 2021 at 13:01, Mark Cave-Ayland
<mark.cave-ayland@ilande.co.uk> wrote:
>
> This new software reset function is to be called when the appropriate channel
> software reset bit is written to register WR9. Its initial implementation is
> the same as the existing escc_reset_chn() function used for device reset.
>
> Add a new trace event when the guest initiates a soft reset via the WR9 register
> to help diagnose guest reset issues.
>
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
>  hw/char/escc.c       | 40 ++++++++++++++++++++++++++++++++++++++--
>  hw/char/trace-events |  1 +
>  2 files changed, 39 insertions(+), 2 deletions(-)
>

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM
diff mbox series

Patch

diff --git a/hw/char/escc.c b/hw/char/escc.c
index b0d3b92dc1..697f15f383 100644
--- a/hw/char/escc.c
+++ b/hw/char/escc.c
@@ -297,6 +297,40 @@  static void escc_reset_chn(ESCCChannelState *s)
     clear_queue(s);
 }
 
+static void escc_soft_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);
@@ -547,10 +581,12 @@  static void escc_mem_write(void *opaque, hwaddr addr,
             default:
                 break;
             case MINTR_RST_B:
-                escc_reset_chn(&serial->chn[0]);
+                trace_escc_soft_reset_chn(CHN_C(&serial->chn[0]));
+                escc_soft_reset_chn(&serial->chn[0]);
                 return;
             case MINTR_RST_A:
-                escc_reset_chn(&serial->chn[1]);
+                trace_escc_soft_reset_chn(CHN_C(&serial->chn[1]));
+                escc_soft_reset_chn(&serial->chn[1]);
                 return;
             case MINTR_RST_ALL:
                 escc_reset(DEVICE(serial));
diff --git a/hw/char/trace-events b/hw/char/trace-events
index 1436fb462d..073f98ebe8 100644
--- a/hw/char/trace-events
+++ b/hw/char/trace-events
@@ -36,6 +36,7 @@  grlib_apbuart_writel_unknown(uint64_t addr, uint32_t value) "addr 0x%"PRIx64" va
 grlib_apbuart_readl_unknown(uint64_t addr) "addr 0x%"PRIx64
 
 # escc.c
+escc_soft_reset_chn(char channel) "soft reset channel %c"
 escc_put_queue(char channel, int b) "channel %c put: 0x%02x"
 escc_get_queue(char channel, int val) "channel %c get 0x%02x"
 escc_update_irq(int irq) "IRQ = %d"