diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/char/serial.c | 59 |
1 files changed, 33 insertions, 26 deletions
diff --git a/hw/char/serial.c b/hw/char/serial.c index 54180a9cba..764e1846cd 100644 --- a/hw/char/serial.c +++ b/hw/char/serial.c @@ -223,37 +223,42 @@ static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) { SerialState *s = opaque; - if (s->tsr_retry <= 0) { - if (s->fcr & UART_FCR_FE) { - if (fifo8_is_empty(&s->xmit_fifo)) { + do { + if (s->tsr_retry <= 0) { + if (s->fcr & UART_FCR_FE) { + if (fifo8_is_empty(&s->xmit_fifo)) { + return FALSE; + } + s->tsr = fifo8_pop(&s->xmit_fifo); + if (!s->xmit_fifo.num) { + s->lsr |= UART_LSR_THRE; + } + } else if ((s->lsr & UART_LSR_THRE)) { return FALSE; - } - s->tsr = fifo8_pop(&s->xmit_fifo); - if (!s->xmit_fifo.num) { + } else { + s->tsr = s->thr; s->lsr |= UART_LSR_THRE; + s->lsr &= ~UART_LSR_TEMT; } - } else if ((s->lsr & UART_LSR_THRE)) { - return FALSE; - } else { - s->tsr = s->thr; - s->lsr |= UART_LSR_THRE; - s->lsr &= ~UART_LSR_TEMT; } - } - if (s->mcr & UART_MCR_LOOP) { - /* in loopback mode, say that we just received a char */ - serial_receive1(s, &s->tsr, 1); - } else if (qemu_chr_fe_write(s->chr, &s->tsr, 1) != 1) { - if (s->tsr_retry >= 0 && s->tsr_retry < MAX_XMIT_RETRY && - qemu_chr_fe_add_watch(s->chr, G_IO_OUT|G_IO_HUP, serial_xmit, s) > 0) { - s->tsr_retry++; - return FALSE; + if (s->mcr & UART_MCR_LOOP) { + /* in loopback mode, say that we just received a char */ + serial_receive1(s, &s->tsr, 1); + } else if (qemu_chr_fe_write(s->chr, &s->tsr, 1) != 1) { + if (s->tsr_retry >= 0 && s->tsr_retry < MAX_XMIT_RETRY && + qemu_chr_fe_add_watch(s->chr, G_IO_OUT|G_IO_HUP, + serial_xmit, s) > 0) { + s->tsr_retry++; + return FALSE; + } + s->tsr_retry = 0; + } else { + s->tsr_retry = 0; } - s->tsr_retry = 0; - } else { - s->tsr_retry = 0; - } + /* Transmit another byte if it is already available. It is only + possible when FIFO is enabled and not empty. */ + } while ((s->fcr & UART_FCR_FE) && !fifo8_is_empty(&s->xmit_fifo)); s->last_xmit_ts = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); @@ -293,7 +298,9 @@ static void serial_ioport_write(void *opaque, hwaddr addr, uint64_t val, s->thr_ipending = 0; s->lsr &= ~UART_LSR_THRE; serial_update_irq(s); - serial_xmit(NULL, G_IO_OUT, s); + if (s->tsr_retry <= 0) { + serial_xmit(NULL, G_IO_OUT, s); + } } break; case 1: |