From 87467bd9052725283b9a9f4b1b310fed8744fb1e Mon Sep 17 00:00:00 2001 From: Brian Niebuhr Date: Wed, 6 Oct 2010 17:03:10 +0530 Subject: spi: davinci: let DMA operation be specified on per-device basis Let DMA operation be specified on a per-device basis instead of selecting it once during probe. A side effect of this is the need to combine the PIO and DMA buffer txrx_bufs routine. This is good since they anyway share some common functionality. Signed-off-by: Brian Niebuhr Tested-By: Michael Williamson Signed-off-by: Sekhar Nori --- arch/arm/mach-davinci/include/mach/spi.h | 1 + drivers/spi/davinci_spi.c | 342 ++++++++++++++----------------- 2 files changed, 156 insertions(+), 187 deletions(-) diff --git a/arch/arm/mach-davinci/include/mach/spi.h b/arch/arm/mach-davinci/include/mach/spi.h index f7586a03678c..b3ab7d04943a 100644 --- a/arch/arm/mach-davinci/include/mach/spi.h +++ b/arch/arm/mach-davinci/include/mach/spi.h @@ -41,6 +41,7 @@ struct davinci_spi_config { u8 parity_enable; #define SPI_IO_TYPE_INTR 0 #define SPI_IO_TYPE_POLL 1 +#define SPI_IO_TYPE_DMA 2 u8 io_type; u8 timer_disable; u8 c2tdelay; diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c index 6094e3a07853..5fe298099a1a 100644 --- a/drivers/spi/davinci_spi.c +++ b/drivers/spi/davinci_spi.c @@ -500,6 +500,25 @@ out: return errors; } +static void davinci_spi_dma_callback(unsigned lch, u16 status, void *data) +{ + struct davinci_spi *davinci_spi = data; + struct davinci_spi_dma *davinci_spi_dma = &davinci_spi->dma_channels; + + edma_stop(lch); + + if (status == DMA_COMPLETE) { + if (lch == davinci_spi_dma->dma_rx_channel) + davinci_spi->rcount = 0; + if (lch == davinci_spi_dma->dma_tx_channel) + davinci_spi->wcount = 0; + } + + if ((!davinci_spi->wcount && !davinci_spi->rcount) || + (status != DMA_COMPLETE)) + complete(&davinci_spi->done); +} + /** * davinci_spi_bufs - functions which will handle transfer data * @spi: spi device on which data transfer to be done @@ -509,25 +528,30 @@ out: * of SPI controller and then wait until the completion will be marked * by the IRQ Handler. */ -static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t) +static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t) { struct davinci_spi *davinci_spi; - int ret; + int data_type, ret; u32 tx_data, data1_reg_val; u32 errors = 0; struct davinci_spi_config *spicfg; struct davinci_spi_platform_data *pdata; + unsigned uninitialized_var(rx_buf_count); + struct device *sdev; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; spicfg = (struct davinci_spi_config *)spi->controller_data; if (!spicfg) spicfg = &davinci_spi_default_cfg; + sdev = davinci_spi->bitbang.master->dev.parent; + + /* convert len to words based on bits_per_word */ + data_type = davinci_spi->bytes_per_word[spi->chip_select]; davinci_spi->tx = t->tx_buf; davinci_spi->rx = t->rx_buf; - davinci_spi->wcount = t->len / - davinci_spi->bytes_per_word[spi->chip_select]; + davinci_spi->wcount = t->len / data_type; davinci_spi->rcount = davinci_spi->wcount; data1_reg_val = ioread32(davinci_spi->base + SPIDAT1); @@ -535,20 +559,117 @@ static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t) /* Enable SPI */ set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); - if (spicfg->io_type == SPI_IO_TYPE_INTR) { + INIT_COMPLETION(davinci_spi->done); + + if (spicfg->io_type == SPI_IO_TYPE_INTR) set_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKINT); - INIT_COMPLETION(davinci_spi->done); - } - /* start the transfer */ - davinci_spi->wcount--; - tx_data = davinci_spi->get_tx(davinci_spi); - data1_reg_val &= 0xFFFF0000; - data1_reg_val |= tx_data & 0xFFFF; - iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); + if (spicfg->io_type != SPI_IO_TYPE_DMA) { + /* start the transfer */ + davinci_spi->wcount--; + tx_data = davinci_spi->get_tx(davinci_spi); + data1_reg_val &= 0xFFFF0000; + data1_reg_val |= tx_data & 0xFFFF; + iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); + } else { + struct davinci_spi_dma *davinci_spi_dma; + unsigned long tx_reg, rx_reg; + struct edmacc_param param; + void *rx_buf; + + davinci_spi_dma = &davinci_spi->dma_channels; + + tx_reg = (unsigned long)davinci_spi->pbase + SPIDAT1; + rx_reg = (unsigned long)davinci_spi->pbase + SPIBUF; + + /* + * Transmit DMA setup + * + * If there is transmit data, map the transmit buffer, set it + * as the source of data and set the source B index to data + * size. If there is no transmit data, set the transmit register + * as the source of data, and set the source B index to zero. + * + * The destination is always the transmit register itself. And + * the destination never increments. + */ + + if (t->tx_buf) { + t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf, + davinci_spi->wcount, DMA_TO_DEVICE); + if (dma_mapping_error(&spi->dev, t->tx_dma)) { + dev_dbg(sdev, "Unable to DMA map %d bytes" + "TX buffer\n", + davinci_spi->wcount); + return -ENOMEM; + } + } + + param.opt = TCINTEN | EDMA_TCC(davinci_spi_dma->dma_tx_channel); + param.src = t->tx_buf ? t->tx_dma : tx_reg; + param.a_b_cnt = davinci_spi->wcount << 16 | data_type; + param.dst = tx_reg; + param.src_dst_bidx = t->tx_buf ? data_type : 0; + param.link_bcntrld = 0xffff; + param.src_dst_cidx = 0; + param.ccnt = 1; + edma_write_slot(davinci_spi_dma->dma_tx_channel, ¶m); + edma_link(davinci_spi_dma->dma_tx_channel, + davinci_spi_dma->dummy_param_slot); + + /* + * Receive DMA setup + * + * If there is receive buffer, use it to receive data. If there + * is none provided, use a temporary receive buffer. Set the + * destination B index to 0 so effectively only one byte is used + * in the temporary buffer (address does not increment). + * + * The source of receive data is the receive data register. The + * source address never increments. + */ + + if (t->rx_buf) { + rx_buf = t->rx_buf; + rx_buf_count = davinci_spi->rcount; + } else { + rx_buf = davinci_spi->rx_tmp_buf; + rx_buf_count = sizeof(davinci_spi->rx_tmp_buf); + } + + t->rx_dma = dma_map_single(&spi->dev, rx_buf, rx_buf_count, + DMA_FROM_DEVICE); + if (dma_mapping_error(&spi->dev, t->rx_dma)) { + dev_dbg(sdev, "Couldn't DMA map a %d bytes RX buffer\n", + rx_buf_count); + if (t->tx_buf) + dma_unmap_single(NULL, t->tx_dma, + davinci_spi->wcount, + DMA_TO_DEVICE); + return -ENOMEM; + } + + param.opt = TCINTEN | EDMA_TCC(davinci_spi_dma->dma_rx_channel); + param.src = rx_reg; + param.a_b_cnt = davinci_spi->rcount << 16 | data_type; + param.dst = t->rx_dma; + param.src_dst_bidx = (t->rx_buf ? data_type : 0) << 16; + param.link_bcntrld = 0xffff; + param.src_dst_cidx = 0; + param.ccnt = 1; + edma_write_slot(davinci_spi_dma->dma_rx_channel, ¶m); + + if (pdata->cshold_bug) + iowrite16(data1_reg_val >> 16, + davinci_spi->base + SPIDAT1 + 2); + + edma_start(davinci_spi_dma->dma_rx_channel); + edma_start(davinci_spi_dma->dma_tx_channel); + set_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); + } /* Wait for the transfer to complete */ - if (spicfg->io_type == SPI_IO_TYPE_INTR) { + if (spicfg->io_type != SPI_IO_TYPE_POLL) { wait_for_completion_interruptible(&(davinci_spi->done)); } else { while (davinci_spi->rcount > 0 || davinci_spi->wcount > 0) { @@ -560,6 +681,17 @@ static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t) } clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL); + if (spicfg->io_type == SPI_IO_TYPE_DMA) { + + if (t->tx_buf) + dma_unmap_single(NULL, t->tx_dma, davinci_spi->wcount, + DMA_TO_DEVICE); + + dma_unmap_single(NULL, t->rx_dma, rx_buf_count, + DMA_FROM_DEVICE); + + clear_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); + } /* * Check for bit error, desync error,parity error,timeout error and @@ -572,6 +704,11 @@ static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t) return ret; } + if (davinci_spi->rcount != 0 || davinci_spi->wcount != 0) { + dev_err(sdev, "SPI data transfer error\n"); + return -EIO; + } + return t->len; } @@ -601,174 +738,6 @@ static irqreturn_t davinci_spi_irq(s32 irq, void *context_data) return IRQ_HANDLED; } -static void davinci_spi_dma_callback(unsigned lch, u16 status, void *data) -{ - struct davinci_spi *davinci_spi = data; - struct davinci_spi_dma *davinci_spi_dma = &davinci_spi->dma_channels; - - edma_stop(lch); - - if (status == DMA_COMPLETE) { - if (lch == davinci_spi_dma->dma_rx_channel) - davinci_spi->rcount = 0; - if (lch == davinci_spi_dma->dma_tx_channel) - davinci_spi->wcount = 0; - } - - if ((!davinci_spi->wcount && !davinci_spi->rcount) || - (status != DMA_COMPLETE)) - complete(&davinci_spi->done); -} - -static int davinci_spi_bufs_dma(struct spi_device *spi, struct spi_transfer *t) -{ - struct davinci_spi *davinci_spi; - int int_status = 0; - unsigned rx_buf_count; - struct davinci_spi_dma *davinci_spi_dma; - int data_type, ret; - unsigned long tx_reg, rx_reg; - struct davinci_spi_platform_data *pdata; - void *rx_buf; - struct device *sdev; - struct edmacc_param param; - - davinci_spi = spi_master_get_devdata(spi->master); - pdata = davinci_spi->pdata; - sdev = davinci_spi->bitbang.master->dev.parent; - - davinci_spi_dma = &davinci_spi->dma_channels; - - /* convert len to words based on bits_per_word */ - data_type = davinci_spi->bytes_per_word[spi->chip_select]; - - tx_reg = (unsigned long)davinci_spi->pbase + SPIDAT1; - rx_reg = (unsigned long)davinci_spi->pbase + SPIBUF; - - davinci_spi->tx = t->tx_buf; - davinci_spi->rx = t->rx_buf; - davinci_spi->wcount = t->len / data_type; - davinci_spi->rcount = davinci_spi->wcount; - - INIT_COMPLETION(davinci_spi->done); - - /* disable all interrupts for dma transfers */ - clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL); - /* Enable SPI */ - set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); - - /* - * Transmit DMA setup - * - * If there is transmit data, map the transmit buffer, set it as the - * source of data and set the source B index to data size. - * If there is no transmit data, set the transmit register as the - * source of data, and set the source B index to zero. - * - * The destination is always the transmit register itself. And the - * destination never increments. - */ - - if (t->tx_buf) { - t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf, - davinci_spi->wcount, DMA_TO_DEVICE); - if (dma_mapping_error(&spi->dev, t->tx_dma)) { - dev_dbg(sdev, "Unable to DMA map %d bytes TX buffer\n", - davinci_spi->wcount); - return -ENOMEM; - } - } - - param.opt = TCINTEN | EDMA_TCC(davinci_spi_dma->dma_tx_channel); - param.src = t->tx_buf ? t->tx_dma : tx_reg; - param.a_b_cnt = davinci_spi->wcount << 16 | data_type; - param.dst = tx_reg; - param.src_dst_bidx = t->tx_buf ? data_type : 0; - param.link_bcntrld = 0xffff; - param.src_dst_cidx = 0; - param.ccnt = 1; - edma_write_slot(davinci_spi_dma->dma_tx_channel, ¶m); - edma_link(davinci_spi_dma->dma_tx_channel, - davinci_spi_dma->dummy_param_slot); - - /* - * Receive DMA setup - * - * If there is receive buffer, use it to receive data. If there - * is none provided, use a temporary receive buffer. Set the - * destination B index to 0 so effectively only one byte is used - * in the temporary buffer (address does not increment). - * - * The source of receive data is the receive data register. The - * source address never increments. - */ - - if (t->rx_buf) { - rx_buf = t->rx_buf; - rx_buf_count = davinci_spi->rcount; - } else { - rx_buf = davinci_spi->rx_tmp_buf; - rx_buf_count = sizeof(davinci_spi->rx_tmp_buf); - } - - t->rx_dma = dma_map_single(&spi->dev, rx_buf, rx_buf_count, - DMA_FROM_DEVICE); - if (dma_mapping_error(&spi->dev, t->rx_dma)) { - dev_dbg(sdev, "Couldn't DMA map a %d bytes RX buffer\n", - rx_buf_count); - if (t->tx_buf) - dma_unmap_single(NULL, t->tx_dma, davinci_spi->wcount, - DMA_TO_DEVICE); - return -ENOMEM; - } - - param.opt = TCINTEN | EDMA_TCC(davinci_spi_dma->dma_rx_channel); - param.src = rx_reg; - param.a_b_cnt = davinci_spi->rcount << 16 | data_type; - param.dst = t->rx_dma; - param.src_dst_bidx = (t->rx_buf ? data_type : 0) << 16; - param.link_bcntrld = 0xffff; - param.src_dst_cidx = 0; - param.ccnt = 1; - edma_write_slot(davinci_spi_dma->dma_rx_channel, ¶m); - - if (pdata->cshold_bug) { - u16 spidat1 = ioread16(davinci_spi->base + SPIDAT1 + 2); - iowrite16(spidat1, davinci_spi->base + SPIDAT1 + 2); - } - - edma_start(davinci_spi_dma->dma_rx_channel); - edma_start(davinci_spi_dma->dma_tx_channel); - set_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); - - wait_for_completion_interruptible(&davinci_spi->done); - - if (t->tx_buf) - dma_unmap_single(NULL, t->tx_dma, davinci_spi->wcount, - DMA_TO_DEVICE); - - dma_unmap_single(NULL, t->rx_dma, rx_buf_count, DMA_FROM_DEVICE); - - clear_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); - - /* - * Check for bit error, desync error,parity error,timeout error and - * receive overflow errors - */ - int_status = ioread32(davinci_spi->base + SPIFLG); - - ret = davinci_spi_check_error(davinci_spi, int_status); - if (ret != 0) - return ret; - - if (davinci_spi->rcount != 0 || davinci_spi->wcount != 0) { - dev_err(sdev, "SPI data transfer error\n"); - return -EIO; - } - - return t->len; -} - static int davinci_spi_request_dma(struct davinci_spi *davinci_spi) { int r; @@ -918,7 +887,7 @@ static int davinci_spi_probe(struct platform_device *pdev) if (r) dma_eventq = r->start; - davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_pio; + davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs; if (dma_rx_chan != SPI_NO_RESOURCE && dma_tx_chan != SPI_NO_RESOURCE && dma_eventq != SPI_NO_RESOURCE) { @@ -930,10 +899,9 @@ static int davinci_spi_probe(struct platform_device *pdev) if (ret) goto free_clk; - davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_dma; - dev_info(&pdev->dev, "DaVinci SPI driver in EDMA mode\n" - "Using RX channel = %d , TX channel = %d and " - "event queue = %d", dma_rx_chan, dma_tx_chan, + dev_info(&pdev->dev, "DMA: supported\n"); + dev_info(&pdev->dev, "DMA: RX channel: %d, TX channel: %d, " + "event queue: %d\n", dma_rx_chan, dma_tx_chan, dma_eventq); } -- cgit v1.2.2