From patchwork Tue Sep 30 21:21:28 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Gross X-Patchwork-Id: 5007321 Return-Path: X-Original-To: patchwork-linux-spi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 26EF8BEEA6 for ; Tue, 30 Sep 2014 21:21:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DE26E201F4 for ; Tue, 30 Sep 2014 21:21:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8DA6D201C7 for ; Tue, 30 Sep 2014 21:21:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751170AbaI3VVj (ORCPT ); Tue, 30 Sep 2014 17:21:39 -0400 Received: from smtp.codeaurora.org ([198.145.11.231]:38836 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750760AbaI3VVi (ORCPT ); Tue, 30 Sep 2014 17:21:38 -0400 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 39F2913FE23; Tue, 30 Sep 2014 21:21:37 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 486) id 2B21113FE28; Tue, 30 Sep 2014 21:21:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from agross.qualcomm.com (rrcs-67-52-129-61.west.biz.rr.com [67.52.129.61]) (using TLSv1.1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: agross@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id AF7F513FE23; Tue, 30 Sep 2014 21:21:35 +0000 (UTC) From: Andy Gross To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, "Ivan T. Ivanov" , Bjorn Andersson , Kumar Gala , Andy Gross Subject: [Patch v3] spi: qup: Fix incorrect block transfers Date: Tue, 30 Sep 2014 16:21:28 -0500 Message-Id: <1412112088-25928-1-git-send-email-agross@codeaurora.org> X-Mailer: git-send-email 1.7.9.5 X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch fixes a number of errors with the QUP block transfer mode. Errors manifested themselves as input underruns, output overruns, and timed out transactions. The block mode does not require the priming that occurs in FIFO mode. At the moment that the QUP is placed into the RUN state, the QUP will immediately raise an interrupt if the request is a write. Therefore, there is no need to prime the pump. In addition, the block transfers require that whole blocks of data are read/written at a time. The last block of data that completes a transaction may contain less than a full blocks worth of data. Each block of data results in an input/output service interrupt accompanied with a input/output block flag set. Additional block reads/writes require clearing of the service flag. It is ok to check for additional blocks of data in the ISR, but you have to ack every block you transfer. Imbalanced acks result in early return from complete transactions with pending interrupts that still have to be ack'd. The next transaction can be affected by these interrupts. Transactions are deemed complete when the MAX_INPUT or MAX_OUTPUT flag are set. Changes from v2: - Added in additional completion check so that transaction done is not prematurely signaled. - Fixed various review comments. Changes from v1: - Split out read/write block function. - Removed extraneous checks for transfer length Signed-off-by: Andy Gross --- drivers/spi/spi-qup.c | 201 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 148 insertions(+), 53 deletions(-) diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c index 9f83d29..889a33a 100644 --- a/drivers/spi/spi-qup.c +++ b/drivers/spi/spi-qup.c @@ -80,6 +80,8 @@ #define QUP_IO_M_MODE_BAM 3 /* QUP_OPERATIONAL fields */ +#define QUP_OP_IN_BLOCK_READ_REQ BIT(13) +#define QUP_OP_OUT_BLOCK_WRITE_REQ BIT(12) #define QUP_OP_MAX_INPUT_DONE_FLAG BIT(11) #define QUP_OP_MAX_OUTPUT_DONE_FLAG BIT(10) #define QUP_OP_IN_SERVICE_FLAG BIT(9) @@ -143,6 +145,7 @@ struct spi_qup { int tx_bytes; int rx_bytes; int qup_v1; + int mode; }; @@ -198,30 +201,14 @@ static int spi_qup_set_state(struct spi_qup *controller, u32 state) return 0; } - -static void spi_qup_fifo_read(struct spi_qup *controller, - struct spi_transfer *xfer) +static void spi_qup_fill_read_buffer(struct spi_qup *controller, + struct spi_transfer *xfer, u32 data) { u8 *rx_buf = xfer->rx_buf; - u32 word, state; - int idx, shift, w_size; - - w_size = controller->w_size; - - while (controller->rx_bytes < xfer->len) { - - state = readl_relaxed(controller->base + QUP_OPERATIONAL); - if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY)) - break; - - word = readl_relaxed(controller->base + QUP_INPUT_FIFO); - - if (!rx_buf) { - controller->rx_bytes += w_size; - continue; - } + int idx, shift; - for (idx = 0; idx < w_size; idx++, controller->rx_bytes++) { + if (rx_buf) + for (idx = 0; idx < controller->w_size; idx++) { /* * The data format depends on bytes per SPI word: * 4 bytes: 0x12345678 @@ -229,41 +216,139 @@ static void spi_qup_fifo_read(struct spi_qup *controller, * 1 byte : 0x00000012 */ shift = BITS_PER_BYTE; - shift *= (w_size - idx - 1); - rx_buf[controller->rx_bytes] = word >> shift; + shift *= (controller->w_size - idx - 1); + rx_buf[controller->rx_bytes + idx] = data >> shift; + } + + controller->rx_bytes += controller->w_size; +} + +static void spi_qup_prepare_write_data(struct spi_qup *controller, + struct spi_transfer *xfer, u32 *data) +{ + const u8 *tx_buf = xfer->tx_buf; + u32 val; + int idx; + + *data = 0; + + if (tx_buf) + for (idx = 0; idx < controller->w_size; idx++) { + val = tx_buf[controller->tx_bytes + idx]; + *data |= val << (BITS_PER_BYTE * (3 - idx)); } + + controller->tx_bytes += controller->w_size; +} + +static void spi_qup_fifo_read(struct spi_qup *controller, + struct spi_transfer *xfer) +{ + u32 data; + + /* clear service request */ + writel_relaxed(QUP_OP_IN_SERVICE_FLAG, + controller->base + QUP_OPERATIONAL); + + while (controller->rx_bytes < xfer->len) { + if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & + QUP_OP_IN_FIFO_NOT_EMPTY)) + break; + + data = readl_relaxed(controller->base + QUP_INPUT_FIFO); + + spi_qup_fill_read_buffer(controller, xfer, data); } } static void spi_qup_fifo_write(struct spi_qup *controller, - struct spi_transfer *xfer) + struct spi_transfer *xfer) { - const u8 *tx_buf = xfer->tx_buf; - u32 word, state, data; - int idx, w_size; + u32 data; - w_size = controller->w_size; + /* clear service request */ + writel_relaxed(QUP_OP_OUT_SERVICE_FLAG, + controller->base + QUP_OPERATIONAL); while (controller->tx_bytes < xfer->len) { - state = readl_relaxed(controller->base + QUP_OPERATIONAL); - if (state & QUP_OP_OUT_FIFO_FULL) + if (readl_relaxed(controller->base + QUP_OPERATIONAL) & + QUP_OP_OUT_FIFO_FULL) break; - word = 0; - for (idx = 0; idx < w_size; idx++, controller->tx_bytes++) { + spi_qup_prepare_write_data(controller, xfer, &data); + writel_relaxed(data, controller->base + QUP_OUTPUT_FIFO); - if (!tx_buf) { - controller->tx_bytes += w_size; - break; - } + } +} - data = tx_buf[controller->tx_bytes]; - word |= data << (BITS_PER_BYTE * (3 - idx)); +static void spi_qup_block_read(struct spi_qup *controller, + struct spi_transfer *xfer) +{ + u32 data; + u32 reads_per_blk = controller->in_blk_sz >> 2; + u32 num_words = (xfer->len - controller->rx_bytes) / controller->w_size; + int i; + + do { + /* ACK by clearing service flag */ + writel_relaxed(QUP_OP_IN_SERVICE_FLAG, + controller->base + QUP_OPERATIONAL); + + /* transfer up to a block size of data in a single pass */ + for (i = 0; num_words && i < reads_per_blk; i++, num_words--) { + + /* read data and fill up rx buffer */ + data = readl_relaxed(controller->base + QUP_INPUT_FIFO); + spi_qup_fill_read_buffer(controller, xfer, data); } - writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO); - } + /* check to see if next block is ready */ + if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & + QUP_OP_IN_BLOCK_READ_REQ)) + break; + + } while (num_words); + + /* + * Due to extra stickiness of the QUP_OP_IN_SERVICE_FLAG during block + * reads, it has to be cleared again at the very end + */ + if (readl_relaxed(controller->base + QUP_OPERATIONAL) & + QUP_OP_MAX_INPUT_DONE_FLAG) + writel_relaxed(QUP_OP_IN_SERVICE_FLAG, + controller->base + QUP_OPERATIONAL); + +} + +static void spi_qup_block_write(struct spi_qup *controller, + struct spi_transfer *xfer) +{ + u32 data; + u32 writes_per_blk = controller->out_blk_sz >> 2; + u32 num_words = (xfer->len - controller->tx_bytes) / controller->w_size; + int i; + + do { + /* ACK by clearing service flag */ + writel_relaxed(QUP_OP_OUT_SERVICE_FLAG, + controller->base + QUP_OPERATIONAL); + + /* transfer up to a block size of data in a single pass */ + for (i = 0; num_words && i < writes_per_blk; i++, num_words--) { + + /* swizzle the bytes for output and write out */ + spi_qup_prepare_write_data(controller, xfer, &data); + writel_relaxed(data, + controller->base + QUP_OUTPUT_FIFO); + } + + /* check to see if next block is ready */ + if (!(readl_relaxed(controller->base + QUP_OPERATIONAL) & + QUP_OP_OUT_BLOCK_WRITE_REQ)) + break; + + } while (num_words); } static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) @@ -285,9 +370,9 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS); writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS); - writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); if (!xfer) { + writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); dev_err_ratelimited(controller->dev, "unexpected irq %08x %08x %08x\n", qup_err, spi_err, opflags); return IRQ_HANDLED; @@ -315,29 +400,37 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) error = -EIO; } - if (opflags & QUP_OP_IN_SERVICE_FLAG) - spi_qup_fifo_read(controller, xfer); + if (opflags & QUP_OP_IN_SERVICE_FLAG) { + if (opflags & QUP_OP_IN_BLOCK_READ_REQ) + spi_qup_block_read(controller, xfer); + else + spi_qup_fifo_read(controller, xfer); + } - if (opflags & QUP_OP_OUT_SERVICE_FLAG) - spi_qup_fifo_write(controller, xfer); + if (opflags & QUP_OP_OUT_SERVICE_FLAG) { + if (opflags & QUP_OP_OUT_BLOCK_WRITE_REQ) + spi_qup_block_write(controller, xfer); + else + spi_qup_fifo_write(controller, xfer); + } spin_lock_irqsave(&controller->lock, flags); controller->error = error; controller->xfer = xfer; spin_unlock_irqrestore(&controller->lock, flags); - if (controller->rx_bytes == xfer->len || error) + if ((controller->rx_bytes == xfer->len && + (opflags & QUP_OP_MAX_INPUT_DONE_FLAG)) || error) complete(&controller->done); return IRQ_HANDLED; } - /* set clock freq ... bits per word */ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer) { struct spi_qup *controller = spi_master_get_devdata(spi->master); - u32 config, iomode, mode; + u32 config, iomode; int ret, n_words, w_size; if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) { @@ -368,14 +461,14 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer) controller->w_size = w_size; if (n_words <= (controller->in_fifo_sz / sizeof(u32))) { - mode = QUP_IO_M_MODE_FIFO; + controller->mode = QUP_IO_M_MODE_FIFO; writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT); writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT); /* must be zero for FIFO */ writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT); writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT); } else { - mode = QUP_IO_M_MODE_BLOCK; + controller->mode = QUP_IO_M_MODE_BLOCK; writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT); writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT); /* must be zero for BLOCK and BAM */ @@ -387,8 +480,8 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer) /* Set input and output transfer mode */ iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK); iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN); - iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT); - iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT); + iomode |= (controller->mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT); + iomode |= (controller->mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT); writel_relaxed(iomode, controller->base + QUP_IO_M_MODES); @@ -462,7 +555,8 @@ static int spi_qup_transfer_one(struct spi_master *master, goto exit; } - spi_qup_fifo_write(controller, xfer); + if (controller->mode == QUP_IO_M_MODE_FIFO) + spi_qup_fifo_write(controller, xfer); if (spi_qup_set_state(controller, QUP_STATE_RUN)) { dev_warn(controller->dev, "cannot set EXECUTE state\n"); @@ -478,6 +572,7 @@ exit: if (!ret) ret = controller->error; spin_unlock_irqrestore(&controller->lock, flags); + return ret; }