The use of phys_to_page is wrong in commit cb06ff102e2d ("ARM: PL011:
Add support for Rx DMA buffer polling."), beacase DMA address is not
physical address. Also, phys_to_page is not declared in some architecture.
The use of virt_to_page is wrong as well because dma_alloc_coherent
implementaion are allowed to returned remapped memory. So I use sg_table
instead of scatterlist and change to dma_get_sgtable() implementaion.Reported-by: Wang, Annie <[email protected]> Signed-off-by: Chanho Min <[email protected]> --- drivers/tty/serial/amba-pl011.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index c0da0cc..ce8840f 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -197,7 +197,7 @@ static struct vendor_data vendor_zte = { /* Deals with DMA transactions */ struct pl011_sgbuf { - struct scatterlist sg; + struct sg_table sgt; char *buf; }; @@ -344,17 +344,23 @@ static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg, enum dma_data_direction dir) { dma_addr_t dma_addr; + int ret; sg->buf = dma_alloc_coherent(chan->device->dev, PL011_DMA_BUFFER_SIZE, &dma_addr, GFP_KERNEL); if (!sg->buf) return -ENOMEM; - sg_init_table(&sg->sg, 1); - sg_set_page(&sg->sg, phys_to_page(dma_addr), - PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr)); - sg_dma_address(&sg->sg) = dma_addr; - sg_dma_len(&sg->sg) = PL011_DMA_BUFFER_SIZE; + ret = dma_get_sgtable(chan->device->dev, &sg->sgt, sg->buf, dma_addr, + PL011_DMA_BUFFER_SIZE); + + if (ret < 0) { + dma_free_coherent(chan->device->dev, + PL011_DMA_BUFFER_SIZE, sg->buf, dma_addr); + return -ENOMEM; + } + sg_dma_address(sg->sgt.sgl) = dma_addr; + sg_dma_len(sg->sgt.sgl) = PL011_DMA_BUFFER_SIZE; return 0; } @@ -365,7 +371,8 @@ static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg, if (sg->buf) { dma_free_coherent(chan->device->dev, PL011_DMA_BUFFER_SIZE, sg->buf, - sg_dma_address(&sg->sg)); + sg_dma_address(sg->sgt.sgl)); + sg_free_table(&sg->sgt); } } @@ -813,7 +820,7 @@ 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; - desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1, + desc = dmaengine_prep_slave_sg(rxchan, sgbuf->sgt.sgl, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); /* @@ -863,7 +870,7 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap, if (uap->dmarx.poll_rate) { /* The data can be taken by polling */ - dmataken = sgbuf->sg.length - dmarx->last_residue; + dmataken = sgbuf->sgt.sgl->length - dmarx->last_residue; /* Recalculate the pending size */ if (pending >= dmataken) pending -= dmataken; @@ -888,7 +895,7 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap, /* Reset the last_residue for Rx DMA poll */ if (uap->dmarx.poll_rate) - dmarx->last_residue = sgbuf->sg.length; + dmarx->last_residue = sgbuf->sgt.sgl->length; /* * Only continue with trying to read the FIFO if all DMA chars have @@ -948,7 +955,7 @@ static void pl011_dma_rx_irq(struct uart_amba_port *uap) pl011_write(uap->dmacr, uap, REG_DMACR); uap->dmarx.running = false; - pending = sgbuf->sg.length - state.residue; + pending = sgbuf->sgt.sgl->length - state.residue; BUG_ON(pending > PL011_DMA_BUFFER_SIZE); /* Then we terminate the transfer - we now know our residue */ dmaengine_terminate_all(rxchan); @@ -994,7 +1001,7 @@ static void pl011_dma_rx_callback(void *data) * 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; + pending = sgbuf->sgt.sgl->length - state.residue; BUG_ON(pending > PL011_DMA_BUFFER_SIZE); /* Then we terminate the transfer - we now know our residue */ dmaengine_terminate_all(rxchan); @@ -1050,7 +1057,7 @@ static void pl011_dma_rx_poll(unsigned long args) sgbuf = dmarx->use_buf_b ? &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state); if (likely(state.residue < dmarx->last_residue)) { - dmataken = sgbuf->sg.length - dmarx->last_residue; + dmataken = sgbuf->sgt.sgl->length - dmarx->last_residue; size = dmarx->last_residue - state.residue; dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken, size); -- 1.7.9.5
