Re: [Qemu-devel] [PATCH 1/2] serial: reset state at startup

[Chen, Tiejun]

On 2014/9/19 20:57, Paolo Bonzini wrote:

Il 19/09/2014 11:17, Chen, Tiejun ha scritto:

On 2014/9/19 16:54, Paolo Bonzini wrote:

When a serial port is started, its initial state is all zero.  Make
it consistent with reset state instead.

Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
   hw/char/serial.c | 1 +
   1 file changed, 1 insertion(+)

diff --git a/hw/char/serial.c b/hw/char/serial.c
index 764e184..4523ccb 100644
--- a/hw/char/serial.c
+++ b/hw/char/serial.c
@@ -668,6 +668,7 @@ void serial_realize_core(SerialState *s, Error
**errp)
                             serial_event, s);

It should just follow qemu_register_reset(serial_reset, s).

       fifo8_create(&s->recv_fifo, UART_FIFO_LENGTH);
       fifo8_create(&s->xmit_fifo, UART_FIFO_LENGTH);
+    serial_reset(s);

Or at least we should push this before this pair of fifo8_create() since

No, it should be _after_ the fifo8_create() pair.  With the current
implementation it doesn't matter, but first you create something and

Yes, I took a look at this pair,

void fifo8_create(Fifo8 *fifo, uint32_t capacity)
{
    fifo->data = g_new(uint8_t, capacity);
    fifo->capacity = capacity;
    fifo->head = 0;
    fifo->num = 0;
}

and

void fifo8_reset(Fifo8 *fifo)
{
    fifo->num = 0;
    fifo->head = 0;
}

then you initialize it, not the other way round.

Thanks for your explanation in this case.

Thanks
Tiejun

Paolo

static void serial_reset(void *opaque)
{
     ...
     fifo8_reset(&s->recv_fifo);
     fifo8_reset(&s->xmit_fifo);


Thanks
Tiejun

   }

   void serial_exit_core(SerialState *s)