From patchwork Tue Dec 4 07:53:54 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenyou Yang X-Patchwork-Id: 1836351 Return-Path: X-Original-To: patchwork-spi-devel-general@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) by patchwork1.kernel.org (Postfix) with ESMTP id 2FCBF3FC71 for ; Tue, 4 Dec 2012 07:59:18 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=sfs-ml-4.v29.ch3.sourceforge.com) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1TfnPR-0008RQ-SG; Tue, 04 Dec 2012 07:59:17 +0000 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1TfnPP-0008Qx-NV for spi-devel-general@lists.sourceforge.net; Tue, 04 Dec 2012 07:59:15 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of atmel.com designates 204.2.163.5 as permitted sender) client-ip=204.2.163.5; envelope-from=Wenyou.Yang@atmel.com; helo=sjogate2.atmel.com; Received: from newsmtp5.atmel.com ([204.2.163.5] helo=sjogate2.atmel.com) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1TfnPN-00087j-2z for spi-devel-general@lists.sourceforge.net; Tue, 04 Dec 2012 07:59:15 +0000 Received: from penbh01.corp.atmel.com ([10.168.5.31]) by sjogate2.atmel.com (8.13.6/8.13.6) with ESMTP id qB47rhHQ014470; Mon, 3 Dec 2012 23:53:44 -0800 (PST) Received: from penmb01.corp.atmel.com ([10.168.5.33]) by penbh01.corp.atmel.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 4 Dec 2012 15:58:58 +0800 Received: from shaarm01.corp.atmel.com ([10.217.6.34]) by penmb01.corp.atmel.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 4 Dec 2012 15:58:54 +0800 From: Wenyou Yang To: linux-arm-kernel@lists.infradead.org Subject: [v2 PATCH 08/14] spi/atmel_spi: add dmaengine support Date: Tue, 4 Dec 2012 15:53:54 +0800 Message-Id: <1354607640-13229-9-git-send-email-wenyou.yang@atmel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1354607640-13229-1-git-send-email-wenyou.yang@atmel.com> References: <1354607640-13229-1-git-send-email-wenyou.yang@atmel.com> X-OriginalArrivalTime: 04 Dec 2012 07:58:56.0140 (UTC) FILETIME=[35ADFCC0:01CDD1F5] X-Spam-Score: -1.5 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Headers-End: 1TfnPN-00087j-2z Cc: richard.genoud@gmail.com, JM.Lin@atmel.com, nicolas.ferre@atmel.com, linux-kernel@vger.kernel.org, wenyou.yang@atmel.com, spi-devel-general@lists.sourceforge.net, plagnioj@jcrosoft.com X-BeenThere: spi-devel-general@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: Linux SPI core/device drivers discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: spi-devel-general-bounces@lists.sourceforge.net From: Nicolas Ferre Add dmaengine support. The has_dma_support to select DMA as the SPI xfer mode. Signed-off-by: Nicolas Ferre [wenyou.yang@atmel.com: add has_dma_support to select DMA as the SPI xfer mode] [wenyou.yang@atmel.com: add support NPCS1,2,3 chip select other than NPCS0] [wenyou.yang@atmel.com: fix DMA: OOPS if buffer > 4096 bytes] Signed-off-by: Wenyou Yang Cc: grant.likely@secretlab.ca Cc: spi-devel-general@lists.sourceforge.net Cc: richard.genoud@gmail.com --- Hi, Richard, This patch is based on the original patch from Nicolas [PATCH] spi/atmel_spi: add dmaengine support and merge the patches from Richard Genoud, [PATCH] spi-atmel: update with dmaengine interface [PATCH] spi-atmel: fix __init/__devinit sections mismatch and Wenyou Yang add the code to support DTS section for selecting the SPI xfer mode, add support NPCS1,2,3 chip select other than NPCS0. fix DMA: OOPS if buffer > 4096 bytes. Could you sign your signature in this patch? Best Regards, Wenyou Yang drivers/spi/spi-atmel.c | 564 ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 532 insertions(+), 32 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index e032e3d..1de45c2 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -25,6 +26,7 @@ #include #include #include +#include /* SPI register offsets */ #define SPI_CR 0x0000 @@ -180,6 +182,19 @@ #define spi_writel(port,reg,value) \ __raw_writel((value), (port)->regs + SPI_##reg) +/* use PIO for small transfers, avoiding DMA setup/teardown overhead and + * cache operations; better heuristics consider wordsize and bitrate. + */ +#define DMA_MIN_BYTES 16 + +struct atmel_spi_dma { + struct dma_chan *chan_rx; + struct dma_chan *chan_tx; + struct scatterlist sgrx; + struct scatterlist sgtx; + struct dma_async_tx_descriptor *data_desc_rx; + struct dma_async_tx_descriptor *data_desc_tx; +}; /* * The core SPI transfer engine just talks to a register bank to set up @@ -188,6 +203,8 @@ */ struct atmel_spi_pdata { u8 version; + bool has_dma_support; + struct at_dma_slave dma_slave; }; struct atmel_spi { @@ -203,6 +220,7 @@ struct atmel_spi { u8 stopping; struct list_head queue; + struct tasklet_struct tasklet; struct spi_transfer *current_transfer; unsigned long current_remaining_bytes; struct spi_transfer *next_transfer; @@ -210,8 +228,15 @@ struct atmel_spi { int done_status; struct atmel_spi_pdata *pdata; + bool use_dma; + bool use_pdc; + + /* scratch buffer */ void *buffer; dma_addr_t buffer_dma; + + /* dmaengine data */ + struct atmel_spi_dma dma; }; /* Controller-specific per-slave state */ @@ -225,14 +250,17 @@ struct atmel_spi_device { static struct atmel_spi_pdata at91rm9200_config = { .version = 1, + .has_dma_support = false, }; static struct atmel_spi_pdata at91sam9260_config = { .version = 2, + .has_dma_support = false, }; static struct atmel_spi_pdata at91sam9x5_config = { .version = 2, + .has_dma_support = true, }; static const struct platform_device_id atmel_spi_devtypes[] = { @@ -309,9 +337,7 @@ static bool atmel_spi_is_v2(struct atmel_spi *as) * and (c) will trigger that first erratum in some cases. * * TODO: Test if the atmel_spi_is_v2() branch below works on - * AT91RM9200 if we use some other register than CSR0. However, don't - * do this unconditionally since AP7000 has an errata where the BITS - * field in CSR0 overrides all other CSRs. + * AT91RM9200 if we use some other register than CSR0. */ static void cs_activate(struct atmel_spi *as, struct spi_device *spi) @@ -321,14 +347,9 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi) u32 mr; if (atmel_spi_is_v2(as)) { - /* - * Always use CSR0. This ensures that the clock - * switches to the correct idle polarity before we - * toggle the CS. - */ - spi_writel(as, CSR0, asd->csr); - spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MODFDIS) - | SPI_BIT(MSTR)); + spi_writel(as, CSR0 + 4 * spi->chip_select, asd->csr); + spi_writel(as, MR, SPI_BF(PCS, ~(0x01 << spi->chip_select)) + | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); mr = spi_readl(as, MR); gpio_set_value(asd->npcs_pin, active); } else { @@ -389,6 +410,23 @@ static void atmel_spi_unlock(struct atmel_spi *as) spin_unlock_irqrestore(&as->lock, as->flags); } +static inline bool atmel_spi_use_dma(struct atmel_spi *as, + struct spi_transfer *xfer) +{ + if ((as->use_dma) && (xfer->len >= DMA_MIN_BYTES)) + return true; + else + return false; +} + +static inline bool atmel_spi_use_pdc(struct atmel_spi *as) +{ + if (as->use_pdc) + return true; + else + return false; +} + static inline int atmel_spi_xfer_is_last(struct spi_message *msg, struct spi_transfer *xfer) { @@ -400,6 +438,220 @@ static inline int atmel_spi_xfer_can_be_chained(struct spi_transfer *xfer) return xfer->delay_usecs == 0 && !xfer->cs_change; } +static bool filter(struct dma_chan *chan, void *slave) +{ + struct at_dma_slave *sl = slave; + + if (sl->dma_dev == chan->device->dev) { + chan->private = sl; + return true; + } else { + return false; + } +} + +static int __devinit atmel_spi_configure_dma(struct atmel_spi *as) +{ + struct at_dma_slave *sdata + = (struct at_dma_slave *)&as->pdata->dma_slave; + + if (sdata && sdata->dma_dev) { + dma_cap_mask_t mask; + + /* setup DMA addresses */ + sdata->rx_reg = (dma_addr_t)as->phybase + SPI_RDR; + sdata->tx_reg = (dma_addr_t)as->phybase + SPI_TDR; + + /* Try to grab two DMA channels */ + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + as->dma.chan_tx = dma_request_channel(mask, filter, sdata); + if (as->dma.chan_tx) + as->dma.chan_rx = + dma_request_channel(mask, filter, sdata); + } + if (!as->dma.chan_rx || !as->dma.chan_tx) { + if (as->dma.chan_rx) + dma_release_channel(as->dma.chan_rx); + if (as->dma.chan_tx) + dma_release_channel(as->dma.chan_tx); + dev_err(&as->pdev->dev, "DMA channel not available, " \ + "unable to use SPI\n"); + return -EBUSY; + } + + dev_info(&as->pdev->dev, "Using %s (tx) and " \ + " %s (rx) for DMA transfers\n", + dma_chan_name(as->dma.chan_tx), + dma_chan_name(as->dma.chan_rx)); + + return 0; +} + +static void atmel_spi_stop_dma(struct atmel_spi *as) +{ + if (as->dma.chan_rx) + as->dma.chan_rx->device->device_control(as->dma.chan_rx, + DMA_TERMINATE_ALL, 0); + if (as->dma.chan_tx) + as->dma.chan_tx->device->device_control(as->dma.chan_tx, + DMA_TERMINATE_ALL, 0); +} + +static void atmel_spi_release_dma(struct atmel_spi *as) +{ + if (as->dma.chan_rx) + dma_release_channel(as->dma.chan_rx); + if (as->dma.chan_tx) + dma_release_channel(as->dma.chan_tx); +} + +/* This function is called by the DMA driver from tasklet context */ +static void dma_callback(void *data) +{ + struct spi_master *master = data; + struct atmel_spi *as = spi_master_get_devdata(master); + + /* trigger SPI tasklet */ + tasklet_schedule(&as->tasklet); +} + +/* + * Next transfer using PIO. + * lock is held, spi tasklet is blocked + */ +static void atmel_spi_next_xfer_pio(struct spi_master *master, + struct spi_transfer *xfer) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + + dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n"); + + as->current_remaining_bytes = xfer->len; + + /* Make sure data is not remaining in RDR */ + spi_readl(as, RDR); + while (spi_readl(as, SR) & SPI_BIT(RDRF)) { + spi_readl(as, RDR); + cpu_relax(); + } + + if (xfer->tx_buf) + spi_writel(as, TDR, *(u8 *)(xfer->tx_buf)); + else + spi_writel(as, TDR, 0); + + dev_dbg(master->dev.parent, + " start pio xfer %p: len %u tx %p rx %p\n", + xfer, xfer->len, xfer->tx_buf, xfer->rx_buf); + + /* Enable relevant interrupts */ + spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES)); +} + +/* + * Submit next transfer for DMA. + * lock is held, spi tasklet is blocked + */ +static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, + struct spi_transfer *xfer, + u32 *plen) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + struct dma_chan *rxchan = as->dma.chan_rx; + struct dma_chan *txchan = as->dma.chan_tx; + struct dma_async_tx_descriptor *rxdesc; + struct dma_async_tx_descriptor *txdesc; + dma_cookie_t cookie; + u32 len = *plen; + + dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n"); + + /* Check that the channels are available */ + if (!rxchan || !txchan) + return -ENODEV; + + /* release lock for DMA operations */ + atmel_spi_unlock(as); + + /* prepare the RX dma transfer */ + sg_init_table(&as->dma.sgrx, 1); + if (xfer->rx_buf) + as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen; + else { + as->dma.sgrx.dma_address = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + } + + /* prepare the TX dma transfer */ + sg_init_table(&as->dma.sgtx, 1); + if (xfer->tx_buf) { + as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen; + } else { + as->dma.sgtx.dma_address = as->buffer_dma; + if (len > BUFFER_SIZE) + len = BUFFER_SIZE; + memset(as->buffer, 0, len); + } + + sg_dma_len(&as->dma.sgtx) = len; + sg_dma_len(&as->dma.sgrx) = len; + + *plen = len; + + /* Send both scatterlists */ + rxdesc = rxchan->device->device_prep_slave_sg(rxchan, + &as->dma.sgrx, + 1, + DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK, + NULL); + if (!rxdesc) + goto err_dma; + + txdesc = txchan->device->device_prep_slave_sg(txchan, + &as->dma.sgtx, + 1, + DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK, + NULL); + if (!txdesc) + goto err_dma; + + dev_dbg(master->dev.parent, + " start dma xfer %p: len %u tx %p/%08x rx %p/%08x\n", + xfer, xfer->len, xfer->tx_buf, xfer->tx_dma, + xfer->rx_buf, xfer->rx_dma); + + /* Enable relevant interrupts */ + spi_writel(as, IER, SPI_BIT(OVRES)); + + /* Put the callback on the RX transfer only, that should finish last */ + rxdesc->callback = dma_callback; + rxdesc->callback_param = master; + + /* Submit and fire RX and TX with TX last so we're ready to read! */ + cookie = rxdesc->tx_submit(rxdesc); + if (dma_submit_error(cookie)) + goto err_dma; + cookie = txdesc->tx_submit(txdesc); + if (dma_submit_error(cookie)) + goto err_dma; + rxchan->device->device_issue_pending(rxchan); + txchan->device->device_issue_pending(txchan); + + /* take back lock */ + atmel_spi_lock(as); + return 0; + +err_dma: + spi_writel(as, IDR, SPI_BIT(OVRES)); + atmel_spi_stop_dma(as); + atmel_spi_lock(as); + return -ENOMEM; +} + static void atmel_spi_next_xfer_data(struct spi_master *master, struct spi_transfer *xfer, dma_addr_t *tx_dma, @@ -432,10 +684,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master, } /* - * Submit next transfer for DMA. + * Submit next transfer for PDC. * lock is held, spi irq is blocked */ -static void atmel_spi_next_xfer(struct spi_master *master, +static void atmel_spi_next_xfer_pdc(struct spi_master *master, struct spi_message *msg) { struct atmel_spi *as = spi_master_get_devdata(master); @@ -532,6 +784,49 @@ static void atmel_spi_next_xfer(struct spi_master *master, spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); } +/* + * Choose way to submit next transfer and start it. + * lock is held, spi tasklet is blocked + */ +static void atmel_spi_next_xfer_dma(struct spi_master *master, + struct spi_message *msg) +{ + struct atmel_spi *as = spi_master_get_devdata(master); + struct spi_transfer *xfer; + u32 remaining, len; + + dev_vdbg(&msg->spi->dev, "atmel_spi_next_xfer\n"); + + remaining = as->current_remaining_bytes; + if (remaining) { + xfer = as->current_transfer; + len = remaining; + } else { + if (!as->current_transfer) + xfer = list_entry(msg->transfers.next, + struct spi_transfer, transfer_list); + else + xfer = list_entry( + as->current_transfer->transfer_list.next, + struct spi_transfer, transfer_list); + + as->current_transfer = xfer; + len = xfer->len; + } + + if (atmel_spi_use_dma(as, xfer)) { + u32 total = len; + if (!atmel_spi_next_xfer_dma_submit(master, xfer, &len)) { + as->current_remaining_bytes = total - len; + return; + } else + dev_err(&msg->spi->dev, "unable to use DMA, fallback to PIO\n"); + } + + /* use PIO if error appened using DMA */ + atmel_spi_next_xfer_pio(master, xfer); +} + static void atmel_spi_next_message(struct spi_master *master) { struct atmel_spi *as = spi_master_get_devdata(master); @@ -556,7 +851,10 @@ static void atmel_spi_next_message(struct spi_master *master) } else cs_activate(as, spi); - atmel_spi_next_xfer(master, msg); + if (atmel_spi_use_pdc(as)) + atmel_spi_next_xfer_pdc(master, msg); + else + atmel_spi_next_xfer_dma(master, msg); } /* @@ -609,6 +907,11 @@ static void atmel_spi_dma_unmap_xfer(struct spi_master *master, xfer->len, DMA_FROM_DEVICE); } +static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as) +{ + spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); +} + static void atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as, struct spi_message *msg, int stay) @@ -634,19 +937,175 @@ atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as, as->done_status = 0; /* continue if needed */ - if (list_empty(&as->queue) || as->stopping) - spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); - else + if (list_empty(&as->queue) || as->stopping) { + if (atmel_spi_use_pdc(as)) + atmel_spi_disable_pdc_transfer(as); + } else atmel_spi_next_message(master); } -static irqreturn_t -atmel_spi_interrupt(int irq, void *dev_id) +/* Called from IRQ + * lock is held + * + * Must update "current_remaining_bytes" to keep track of data + * to transfer. + */ +static void +atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) { - struct spi_master *master = dev_id; + u8 *txp; + u8 *rxp; + unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; + + if (xfer->rx_buf) { + rxp = ((u8 *)xfer->rx_buf) + xfer_pos; + *rxp = spi_readl(as, RDR); + } else { + spi_readl(as, RDR); + } + + as->current_remaining_bytes--; + + if (as->current_remaining_bytes) { + if (xfer->tx_buf) { + txp = ((u8 *)xfer->tx_buf) + xfer_pos + 1; + spi_writel(as, TDR, *txp); + } else { + spi_writel(as, TDR, 0); + } + } +} + +/* Tasklet + * Called from DMA callback + pio transfer and overrun IRQ. + */ +static void atmel_spi_tasklet_func(unsigned long data) +{ + struct spi_master *master = (struct spi_master *)data; struct atmel_spi *as = spi_master_get_devdata(master); struct spi_message *msg; struct spi_transfer *xfer; + + dev_vdbg(master->dev.parent, "atmel_spi_tasklet_func\n"); + + atmel_spi_lock(as); + + xfer = as->current_transfer; + + if (xfer == NULL) + /* already been there */ + goto tasklet_out; + + msg = list_entry(as->queue.next, struct spi_message, queue); + + if (as->current_remaining_bytes == 0) { + if (as->done_status < 0) { + /* error happened (overrun) */ + if (atmel_spi_use_dma(as, xfer)) + atmel_spi_stop_dma(as); + } else + /* only update length if no error */ + msg->actual_length += xfer->len; + + if (atmel_spi_use_dma(as, xfer)) + if (!msg->is_dma_mapped) + atmel_spi_dma_unmap_xfer(master, xfer); + + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + + if (atmel_spi_xfer_is_last(msg, xfer) || as->done_status < 0) + /* report completed (or erroneous) message */ + atmel_spi_msg_done(master, as, msg, xfer->cs_change); + else { + if (xfer->cs_change) { + cs_deactivate(as, msg->spi); + udelay(1); + cs_activate(as, msg->spi); + } + + /* + * Not done yet. Submit the next transfer. + * + * FIXME handle protocol options for xfer + */ + atmel_spi_next_xfer_dma(master, msg); + } + } else + /* + * Keep going, we still have data to send in + * the current transfer. + */ + atmel_spi_next_xfer_dma(master, msg); + +tasklet_out: + atmel_spi_unlock(as); +} + +static int atmel_spi_interrupt_dma(struct atmel_spi *as, + struct spi_master *master) +{ + u32 status, pending, imr; + struct spi_transfer *xfer; + int ret = IRQ_NONE; + + imr = spi_readl(as, IMR); + status = spi_readl(as, SR); + pending = status & imr; + + if (pending & SPI_BIT(OVRES)) { + ret = IRQ_HANDLED; + spi_writel(as, IDR, SPI_BIT(OVRES)); + dev_warn(master->dev.parent, "overrun\n"); + + /* + * When we get an overrun, we disregard the current + * transfer. Data will not be copied back from any + * bounce buffer and msg->actual_len will not be + * updated with the last xfer. + * + * We will also not process any remaning transfers in + * the message. + * + * All actions are done in tasklet with done_status indication + */ + as->done_status = -EIO; + smp_wmb(); + + /* Clear any overrun happening while cleaning up */ + spi_readl(as, SR); + + tasklet_schedule(&as->tasklet); + + } else if (pending & SPI_BIT(RDRF)) { + atmel_spi_lock(as); + + if (as->current_remaining_bytes) { + ret = IRQ_HANDLED; + xfer = as->current_transfer; + atmel_spi_pump_pio_data(as, xfer); + if (!as->current_remaining_bytes) { + /* no more data to xfer, kick tasklet */ + spi_writel(as, IDR, pending); + tasklet_schedule(&as->tasklet); + } + } + + atmel_spi_unlock(as); + } else { + WARN_ONCE(pending, "IRQ not handled, pending = %x\n", pending); + ret = IRQ_HANDLED; + spi_writel(as, IDR, pending); + } + + return ret; +} + +static int atmel_spi_interrupt_pdc(struct atmel_spi *as, + struct spi_master *master) +{ + struct spi_message *msg; + struct spi_transfer *xfer; u32 status, pending, imr; int ret = IRQ_NONE; @@ -742,14 +1201,14 @@ atmel_spi_interrupt(int irq, void *dev_id) * * FIXME handle protocol options for xfer */ - atmel_spi_next_xfer(master, msg); + atmel_spi_next_xfer_pdc(master, msg); } } else { /* * Keep going, we still have data to send in * the current transfer. */ - atmel_spi_next_xfer(master, msg); + atmel_spi_next_xfer_pdc(master, msg); } } @@ -758,6 +1217,27 @@ atmel_spi_interrupt(int irq, void *dev_id) return ret; } +/* Interrupt + * + * No need for locking in this Interrupt handler: done_status is the + * only information modified. What we need is the update of this field + * before tasklet runs. This is ensured by using barrier. + */ +static irqreturn_t +atmel_spi_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct atmel_spi *as = spi_master_get_devdata(master); + int ret; + + if (atmel_spi_use_pdc(as)) + ret = atmel_spi_interrupt_pdc(as, master); + else + ret = atmel_spi_interrupt_dma(as, master); + + return ret; +} + static int atmel_spi_setup(struct spi_device *spi) { struct atmel_spi *as; @@ -918,13 +1398,10 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg) /* * DMA map early, for performance (empties dcache ASAP) and - * better fault reporting. This is a DMA-only driver. - * - * NOTE that if dma_unmap_single() ever starts to do work on - * platforms supported by this driver, we would need to clean - * up mappings for previously-mapped transfers. + * better fault reporting. */ - if (!msg->is_dma_mapped) { + if ((!msg->is_dma_mapped) && (atmel_spi_use_dma(as, xfer) + || atmel_spi_use_pdc(as))) { if (atmel_spi_dma_map_xfer(as, xfer) < 0) return -ENOMEM; } @@ -1041,6 +1518,8 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev) spin_lock_init(&as->lock); INIT_LIST_HEAD(&as->queue); + tasklet_init(&as->tasklet, atmel_spi_tasklet_func, + (unsigned long)master); as->pdev = pdev; as->regs = ioremap(regs->start, resource_size(regs)); if (!as->regs) @@ -1063,7 +1542,16 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev) spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS)); - spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); + + as->use_dma = false; + as->use_pdc = false; + + if (as->pdata->has_dma_support) { + if (atmel_spi_configure_dma(as) == 0) + as->use_dma = true; + } else + as->use_pdc = true; + spi_writel(as, CR, SPI_BIT(SPIEN)); /* go! */ @@ -1072,11 +1560,14 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev) ret = spi_register_master(master); if (ret) - goto out_reset_hw; + goto out_free_dma; return 0; -out_reset_hw: +out_free_dma: + if (as->use_dma) + atmel_spi_release_dma(as); + spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ clk_disable(clk); @@ -1084,6 +1575,7 @@ out_reset_hw: out_unmap_regs: iounmap(as->regs); out_free_buffer: + tasklet_kill(&as->tasklet); dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, as->buffer_dma); out_free: @@ -1102,6 +1594,11 @@ static int __devexit atmel_spi_remove(struct platform_device *pdev) /* reset the hardware and block queue progress */ spin_lock_irq(&as->lock); as->stopping = 1; + if (as->use_dma) { + atmel_spi_stop_dma(as); + atmel_spi_release_dma(as); + } + spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ spi_readl(as, SR); @@ -1110,13 +1607,16 @@ static int __devexit atmel_spi_remove(struct platform_device *pdev) /* Terminate remaining queued transfers */ list_for_each_entry(msg, &as->queue, queue) { list_for_each_entry(xfer, &msg->transfers, transfer_list) { - if (!msg->is_dma_mapped) + if (!msg->is_dma_mapped + && (atmel_spi_use_dma(as, xfer) + || atmel_spi_use_pdc(as))) atmel_spi_dma_unmap_xfer(master, xfer); } msg->status = -ESHUTDOWN; msg->complete(msg->context); } + tasklet_kill(&as->tasklet); dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, as->buffer_dma);