diff options
| -rw-r--r-- | hw/grlib_apbuart.c | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/hw/grlib_apbuart.c b/hw/grlib_apbuart.c index 3a61788a72..ba1685afd1 100644 --- a/hw/grlib_apbuart.c +++ b/hw/grlib_apbuart.c @@ -75,7 +75,6 @@ typedef struct UART { CharDriverState *chr; /* registers */ - uint32_t receive; uint32_t status; uint32_t control; @@ -136,12 +135,14 @@ static void grlib_apbuart_receive(void *opaque, const uint8_t *buf, int size) { UART *uart = opaque; - uart_add_to_fifo(uart, buf, size); + if (uart->control & UART_RECEIVE_ENABLE) { + uart_add_to_fifo(uart, buf, size); - uart->status |= UART_DATA_READY; + uart->status |= UART_DATA_READY; - if (uart->control & UART_RECEIVE_INTERRUPT) { - qemu_irq_pulse(uart->irq); + if (uart->control & UART_RECEIVE_INTERRUPT) { + qemu_irq_pulse(uart->irq); + } } } @@ -193,8 +194,15 @@ static void grlib_apbuart_write(void *opaque, hwaddr addr, switch (addr) { case DATA_OFFSET: case DATA_OFFSET + 3: /* When only one byte write */ - c = value & 0xFF; - qemu_chr_fe_write(uart->chr, &c, 1); + /* Transmit when character device available and transmitter enabled */ + if ((uart->chr) && (uart->control & UART_TRANSMIT_ENABLE)) { + c = value & 0xFF; + qemu_chr_fe_write(uart->chr, &c, 1); + /* Generate interrupt */ + if (uart->control & UART_TRANSMIT_INTERRUPT) { + qemu_irq_pulse(uart->irq); + } + } return; case STATUS_OFFSET: @@ -242,6 +250,19 @@ static int grlib_apbuart_init(SysBusDevice *dev) return 0; } +static void grlib_apbuart_reset(DeviceState *d) +{ + UART *uart = container_of(d, UART, busdev.qdev); + + /* Transmitter FIFO and shift registers are always empty in QEMU */ + uart->status = UART_TRANSMIT_FIFO_EMPTY | UART_TRANSMIT_SHIFT_EMPTY; + /* Everything is off */ + uart->control = 0; + /* Flush receive FIFO */ + uart->len = 0; + uart->current = 0; +} + static Property grlib_apbuart_properties[] = { DEFINE_PROP_CHR("chrdev", UART, chr), DEFINE_PROP_END_OF_LIST(), @@ -253,6 +274,7 @@ static void grlib_apbuart_class_init(ObjectClass *klass, void *data) SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); k->init = grlib_apbuart_init; + dc->reset = grlib_apbuart_reset; dc->props = grlib_apbuart_properties; } |