diff options
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index b604274c1791..028e37ad8d79 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -649,6 +649,15 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) count = PL011_DMA_BUFFER_SIZE; count = kfifo_out_peek(&tport->xmit_fifo, dmatx->buf, count); + + /* + * Align the TX buffer length to the DMA controller's copy_align + * requirements. Some DMA controllers (e.g., Tegra GPC DMA) require + * word-aligned transfers. Unaligned bytes will be sent via PIO. + */ + if (chan->device->copy_align) + count = ALIGN_DOWN(count, 1 << chan->device->copy_align); + dmatx->len = count; dmatx->dma = dma_map_single(dma_dev->dev, dmatx->buf, count, DMA_TO_DEVICE); |