diff options
| author | Peter Crosthwaite <peter.crosthwaite@xilinx.com> | 2014-01-06 10:16:40 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2014-01-07 19:18:06 +0000 |
| commit | 9e263f73912ba35510d7d7be4c40ba871d4b57e2 (patch) | |
| tree | 9585d14af630793bfe89e75e587eae5f65ec6f36 | |
| parent | 61654c77413d1bccb69b384d891d0c688a31430b (diff) | |
char/cadence_uart: Use the TX fifo for transmission
Populate the TxFIFO with the Tx data before sending. Prepares
support for proper Tx flow control implementation.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: bdf7f8af2ef02839bea18665701bc2612f7baa6f.1388626249.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
| -rw-r--r-- | hw/char/cadence_uart.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/hw/char/cadence_uart.c b/hw/char/cadence_uart.c index 3bcaf2905d..be32126bdc 100644 --- a/hw/char/cadence_uart.c +++ b/hw/char/cadence_uart.c @@ -292,7 +292,22 @@ static void uart_write_tx_fifo(UartState *s, const uint8_t *buf, int size) return; } - qemu_chr_fe_write_all(s->chr, buf, size); + if (size > TX_FIFO_SIZE - s->tx_count) { + size = TX_FIFO_SIZE - s->tx_count; + /* + * This can only be a guest error via a bad tx fifo register push, + * as can_receive() should stop remote loop and echo modes ever getting + * us to here. + */ + qemu_log_mask(LOG_GUEST_ERROR, "cadence_uart: TxFIFO overflow"); + s->r[R_CISR] |= UART_INTR_ROVR; + } + + memcpy(s->tx_fifo + s->tx_count, buf, size); + s->tx_count += size; + + qemu_chr_fe_write_all(s->chr, s->tx_fifo, s->tx_count); + s->tx_count = 0; } static void uart_receive(void *opaque, const uint8_t *buf, int size) |