diff options
Diffstat (limited to 'drivers/tty/serial/amba-pl011.c')
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 41 |
1 files changed, 32 insertions, 9 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 6800f5f..3d569cd 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -51,6 +51,7 @@ #include <linux/dma-mapping.h> #include <linux/scatterlist.h> #include <linux/delay.h> +#include <linux/types.h> #include <asm/io.h> #include <asm/sizes.h> @@ -271,6 +272,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap) .dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, .direction = DMA_MEM_TO_DEV, .dst_maxburst = uap->fifosize >> 1, + .device_fc = false, }; struct dma_chan *chan; dma_cap_mask_t mask; @@ -304,6 +306,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap) .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, .direction = DMA_DEV_TO_MEM, .src_maxburst = uap->fifosize >> 1, + .device_fc = false, }; chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param); @@ -481,7 +484,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) return -EBUSY; } - desc = dma_dev->device_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV, + desc = dmaengine_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) { dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE); @@ -664,7 +667,6 @@ static void pl011_dma_rx_callback(void *data); static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) { struct dma_chan *rxchan = uap->dmarx.chan; - struct dma_device *dma_dev; struct pl011_dmarx_data *dmarx = &uap->dmarx; struct dma_async_tx_descriptor *desc; struct pl011_sgbuf *sgbuf; @@ -675,8 +677,7 @@ static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) /* Start the RX DMA job */ sgbuf = uap->dmarx.use_buf_b ? &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; - dma_dev = rxchan->device; - desc = rxchan->device->device_prep_slave_sg(rxchan, &sgbuf->sg, 1, + desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); /* @@ -827,7 +828,12 @@ static void pl011_dma_rx_callback(void *data) { struct uart_amba_port *uap = data; struct pl011_dmarx_data *dmarx = &uap->dmarx; + struct dma_chan *rxchan = dmarx->chan; bool lastbuf = dmarx->use_buf_b; + struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? + &dmarx->sgbuf_b : &dmarx->sgbuf_a; + size_t pending; + struct dma_tx_state state; int ret; /* @@ -838,11 +844,21 @@ static void pl011_dma_rx_callback(void *data) * we immediately trigger the next DMA job. */ spin_lock_irq(&uap->port.lock); + /* + * Rx data can be taken by the UART interrupts during + * the DMA irq handler. So we check the residue here. + */ + rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state); + pending = sgbuf->sg.length - state.residue; + BUG_ON(pending > PL011_DMA_BUFFER_SIZE); + /* Then we terminate the transfer - we now know our residue */ + dmaengine_terminate_all(rxchan); + uap->dmarx.running = false; dmarx->use_buf_b = !lastbuf; ret = pl011_dma_rx_trigger_dma(uap); - pl011_dma_rx_chars(uap, PL011_DMA_BUFFER_SIZE, lastbuf, false); + pl011_dma_rx_chars(uap, pending, lastbuf, false); spin_unlock_irq(&uap->port.lock); /* * Do this check after we picked the DMA chars so we don't @@ -1381,6 +1397,10 @@ static int pl011_startup(struct uart_port *port) uap->port.uartclk = clk_get_rate(uap->clk); + /* Clear pending error and receive interrupts */ + writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS | + UART011_RTIS | UART011_RXIS, uap->port.membase + UART011_ICR); + /* * Allocate the IRQ */ @@ -1417,10 +1437,6 @@ static int pl011_startup(struct uart_port *port) cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE; writew(cr, uap->port.membase + UART011_CR); - /* Clear pending error interrupts */ - writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS, - uap->port.membase + UART011_ICR); - /* * initialise the old status of the modem signals */ @@ -1435,6 +1451,9 @@ static int pl011_startup(struct uart_port *port) * as well. */ spin_lock_irq(&uap->port.lock); + /* Clear out any spuriously appearing RX interrupts */ + writew(UART011_RTIS | UART011_RXIS, + uap->port.membase + UART011_ICR); uap->im = UART011_RTIM; if (!pl011_dma_rx_running(uap)) uap->im |= UART011_RXIM; @@ -1944,6 +1963,10 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) uap->port.line = i; pl011_dma_probe(uap); + /* Ensure interrupts from this UART are masked and cleared */ + writew(0, uap->port.membase + UART011_IMSC); + writew(0xffff, uap->port.membase + UART011_ICR); + snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev)); amba_ports[i] = uap; |