diff options
| -rw-r--r-- | hw/char/ibex_uart.c | 23 | ||||
| -rw-r--r-- | include/hw/char/ibex_uart.h | 4 |
2 files changed, 22 insertions, 5 deletions
diff --git a/hw/char/ibex_uart.c b/hw/char/ibex_uart.c index edcaa30..73b8f2e 100644 --- a/hw/char/ibex_uart.c +++ b/hw/char/ibex_uart.c @@ -66,7 +66,8 @@ static int ibex_uart_can_receive(void *opaque) { IbexUartState *s = opaque; - if (s->uart_ctrl & R_CTRL_RX_ENABLE_MASK) { + if ((s->uart_ctrl & R_CTRL_RX_ENABLE_MASK) + && !(s->uart_status & R_STATUS_RXFULL_MASK)) { return 1; } @@ -83,6 +84,11 @@ static void ibex_uart_receive(void *opaque, const uint8_t *buf, int size) s->uart_status &= ~R_STATUS_RXIDLE_MASK; s->uart_status &= ~R_STATUS_RXEMPTY_MASK; + /* The RXFULL is set after receiving a single byte + * as the FIFO buffers are not yet implemented. + */ + s->uart_status |= R_STATUS_RXFULL_MASK; + s->rx_level += 1; if (size > rx_fifo_level) { s->uart_intr_state |= R_INTR_STATE_RX_WATERMARK_MASK; @@ -199,6 +205,7 @@ static void ibex_uart_reset(DeviceState *dev) s->uart_timeout_ctrl = 0x00000000; s->tx_level = 0; + s->rx_level = 0; s->char_tx_time = (NANOSECONDS_PER_SECOND / 230400) * 10; @@ -243,11 +250,15 @@ static uint64_t ibex_uart_read(void *opaque, hwaddr addr, case R_RDATA: retvalue = s->uart_rdata; - if (s->uart_ctrl & R_CTRL_RX_ENABLE_MASK) { + if ((s->uart_ctrl & R_CTRL_RX_ENABLE_MASK) && (s->rx_level > 0)) { qemu_chr_fe_accept_input(&s->chr); - s->uart_status |= R_STATUS_RXIDLE_MASK; - s->uart_status |= R_STATUS_RXEMPTY_MASK; + s->rx_level -= 1; + s->uart_status &= ~R_STATUS_RXFULL_MASK; + if (s->rx_level == 0) { + s->uart_status |= R_STATUS_RXIDLE_MASK; + s->uart_status |= R_STATUS_RXEMPTY_MASK; + } } break; case R_WDATA: @@ -261,7 +272,8 @@ static uint64_t ibex_uart_read(void *opaque, hwaddr addr, case R_FIFO_STATUS: retvalue = s->uart_fifo_status; - retvalue |= s->tx_level & 0x1F; + retvalue |= (s->rx_level & 0x1F) << R_FIFO_STATUS_RXLVL_SHIFT; + retvalue |= (s->tx_level & 0x1F) << R_FIFO_STATUS_TXLVL_SHIFT; qemu_log_mask(LOG_UNIMP, "%s: RX fifos are not supported\n", __func__); @@ -364,6 +376,7 @@ static void ibex_uart_write(void *opaque, hwaddr addr, s->uart_fifo_ctrl = value; if (value & R_FIFO_CTRL_RXRST_MASK) { + s->rx_level = 0; qemu_log_mask(LOG_UNIMP, "%s: RX fifos are not supported\n", __func__); } diff --git a/include/hw/char/ibex_uart.h b/include/hw/char/ibex_uart.h index 03d19e3..546f958 100644 --- a/include/hw/char/ibex_uart.h +++ b/include/hw/char/ibex_uart.h @@ -62,6 +62,8 @@ REG32(FIFO_CTRL, 0x1c) FIELD(FIFO_CTRL, RXILVL, 2, 3) FIELD(FIFO_CTRL, TXILVL, 5, 2) REG32(FIFO_STATUS, 0x20) + FIELD(FIFO_STATUS, TXLVL, 0, 5) + FIELD(FIFO_STATUS, RXLVL, 16, 5) REG32(OVRD, 0x24) REG32(VAL, 0x28) REG32(TIMEOUT_CTRL, 0x2c) @@ -82,6 +84,8 @@ struct IbexUartState { uint8_t tx_fifo[IBEX_UART_TX_FIFO_SIZE]; uint32_t tx_level; + uint32_t rx_level; + QEMUTimer *fifo_trigger_handle; uint64_t char_tx_time; |