From patchwork Thu Dec 8 14:25:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijaya Krishna Nivarthi X-Patchwork-Id: 13068504 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E10F6C63703 for ; Thu, 8 Dec 2022 14:27:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229825AbiLHO1L (ORCPT ); Thu, 8 Dec 2022 09:27:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230137AbiLHO0I (ORCPT ); Thu, 8 Dec 2022 09:26:08 -0500 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD6AD45A17; Thu, 8 Dec 2022 06:25:58 -0800 (PST) Received: from pps.filterd (m0279873.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2B8DJwAS031048; Thu, 8 Dec 2022 14:25:53 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id; s=qcppdkim1; bh=2x4FctKgQPV6Z/H0SPs68LZKyHxcfHZ0YWVpGUUlRgc=; b=lZhRpXsQWhGsRsHvj7A8Bv/LgXc70LUUlrSfsFgT+C5J8KrbcYSowz6B8JSL2z8QzqUd kimPXjXgEGMCAC9JbiEpJmJb4pPt25aXikA5vLCnb2fy4m4MW48CkjzJKfaTfZokR1nn ir088lNYMGZHFXv6hnNUCH10BQt6By+aSKK/V3EEnGZxTIddeYyEN8Tc6swb+mQ8Uw4s giwjRlZosuNuuPWOGtVt4V6ypvihtcBrWRbJmPbkz9dkZDM3YWeGB3WTNIaHKNyiQ80t tPu1ZUBL8kgJhzsUVNZiITn5MkDhTR6XkrvlmAq/BEBHm1u2Y7m/jIaOKZQMd9hiPjNH 0Q== Received: from apblrppmta02.qualcomm.com (blr-bdr-fw-01_GlobalNAT_AllZones-Outside.qualcomm.com [103.229.18.19]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3mb7bc9jqt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 08 Dec 2022 14:25:52 +0000 Received: from pps.filterd (APBLRPPMTA02.qualcomm.com [127.0.0.1]) by APBLRPPMTA02.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTP id 2B8EPmWG013724; Thu, 8 Dec 2022 14:25:48 GMT Received: from pps.reinject (localhost [127.0.0.1]) by APBLRPPMTA02.qualcomm.com (PPS) with ESMTPS id 3m8g0behce-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 08 Dec 2022 14:25:48 +0000 Received: from APBLRPPMTA02.qualcomm.com (APBLRPPMTA02.qualcomm.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 2B8EPmcE013717; Thu, 8 Dec 2022 14:25:48 GMT Received: from hu-sgudaval-hyd.qualcomm.com (hu-vnivarth-hyd.qualcomm.com [10.213.111.166]) by APBLRPPMTA02.qualcomm.com (PPS) with ESMTP id 2B8EPm7r013716; Thu, 08 Dec 2022 14:25:48 +0000 Received: by hu-sgudaval-hyd.qualcomm.com (Postfix, from userid 3994820) id 837584610; Thu, 8 Dec 2022 19:55:47 +0530 (+0530) From: Vijaya Krishna Nivarthi To: agross@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org, broonie@kernel.org, linux-arm-msm@vger.kernel.org, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: quic_msavaliy@quicinc.com, dianders@chromium.org, mka@chromium.org, swboyd@chromium.org, quic_vtanuku@quicinc.com, vkoul@kernel.org, quic_arandive@quicinc.com, quic_ramkri@quicinc.com, Vijaya Krishna Nivarthi Subject: [V4] spi: spi-geni-qcom: Add support for SE DMA mode Date: Thu, 8 Dec 2022 19:55:44 +0530 Message-Id: <1670509544-15977-1-git-send-email-quic_vnivarth@quicinc.com> X-Mailer: git-send-email 2.7.4 X-QCInternal: smtphost X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: uYMcWZmUfxfmpQOI4KSvJkZRHMwxHAji X-Proofpoint-ORIG-GUID: uYMcWZmUfxfmpQOI4KSvJkZRHMwxHAji X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.923,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-12-08_07,2022-12-08_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 mlxscore=0 spamscore=0 suspectscore=0 priorityscore=1501 impostorscore=0 bulkscore=0 adultscore=0 clxscore=1015 phishscore=0 malwarescore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2212080120 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org SE DMA mode can be used for larger transfers and FIFO mode for smaller transfers. Signed-off-by: Vijaya Krishna Nivarthi Reviewed-by: Douglas Anderson --- v4 -> v3: - remove cur_m_cmd field - add dma_addr fields to spi_geni_master - dont use dma_addr from xfer, use above - dev_warn instead of dev_err in handle_timeout - set xfer_mode to FIFO in set_cs v2 -> v3: - indentation change - readability change v1 -> v2: - replace writel_relaxed with writel - corrected order of performing FSM reset and dma_unprep - added more comments in geni_can_dma - removed redundant change in spi_geni_init(DMA as default xfer_mode) - removed redundant initialisations in setup_se_xfer - removed redundant null checks in setup_se_xfer - added dma_tx_prep failure handling(rx un_map) in setup_se_xfer - move handing return of setip_se_xfer to transfer_one - apply irq error handling for DMA mode too in geni_spi_isr --- drivers/spi/spi-geni-qcom.c | 211 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 165 insertions(+), 46 deletions(-) diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c index 4e83cc5..e1b2e0b 100644 --- a/drivers/spi/spi-geni-qcom.c +++ b/drivers/spi/spi-geni-qcom.c @@ -87,6 +87,8 @@ struct spi_geni_master { struct completion cs_done; struct completion cancel_done; struct completion abort_done; + struct completion tx_reset_done; + struct completion rx_reset_done; unsigned int oversampling; spinlock_t lock; int irq; @@ -95,6 +97,8 @@ struct spi_geni_master { struct dma_chan *tx; struct dma_chan *rx; int cur_xfer_mode; + dma_addr_t tx_se_dma; + dma_addr_t rx_se_dma; }; static int get_spi_clk_cfg(unsigned int speed_hz, @@ -129,23 +133,27 @@ static int get_spi_clk_cfg(unsigned int speed_hz, return ret; } -static void handle_fifo_timeout(struct spi_master *spi, +static void handle_se_timeout(struct spi_master *spi, struct spi_message *msg) { struct spi_geni_master *mas = spi_master_get_devdata(spi); unsigned long time_left; struct geni_se *se = &mas->se; + const struct spi_transfer *xfer; spin_lock_irq(&mas->lock); reinit_completion(&mas->cancel_done); - writel(0, se->base + SE_GENI_TX_WATERMARK_REG); + if (mas->cur_xfer_mode == GENI_SE_FIFO) + writel(0, se->base + SE_GENI_TX_WATERMARK_REG); + + xfer = mas->cur_xfer; mas->cur_xfer = NULL; geni_se_cancel_m_cmd(se); spin_unlock_irq(&mas->lock); time_left = wait_for_completion_timeout(&mas->cancel_done, HZ); if (time_left) - return; + goto unmap_if_dma; spin_lock_irq(&mas->lock); reinit_completion(&mas->abort_done); @@ -162,6 +170,39 @@ static void handle_fifo_timeout(struct spi_master *spi, */ mas->abort_failed = true; } + +unmap_if_dma: + if (mas->cur_xfer_mode == GENI_SE_DMA) { + if (xfer) { + if (xfer->tx_buf && mas->tx_se_dma) { + spin_lock_irq(&mas->lock); + reinit_completion(&mas->tx_reset_done); + writel(1, se->base + SE_DMA_TX_FSM_RST); + spin_unlock_irq(&mas->lock); + time_left = wait_for_completion_timeout(&mas->tx_reset_done, HZ); + if (!time_left) + dev_err(mas->dev, "DMA TX RESET failed\n"); + geni_se_tx_dma_unprep(se, mas->tx_se_dma, xfer->len); + } + if (xfer->rx_buf && mas->rx_se_dma) { + spin_lock_irq(&mas->lock); + reinit_completion(&mas->rx_reset_done); + writel(1, se->base + SE_DMA_RX_FSM_RST); + spin_unlock_irq(&mas->lock); + time_left = wait_for_completion_timeout(&mas->rx_reset_done, HZ); + if (!time_left) + dev_err(mas->dev, "DMA RX RESET failed\n"); + geni_se_rx_dma_unprep(se, mas->rx_se_dma, xfer->len); + } + } else { + /* + * This can happen if a timeout happened and we had to wait + * for lock in this function because isr was holding the lock + * and handling transfer completion at that time. + */ + dev_warn(mas->dev, "Cancel/Abort on completed SPI transfer\n"); + } + } } static void handle_gpi_timeout(struct spi_master *spi, struct spi_message *msg) @@ -178,7 +219,8 @@ static void spi_geni_handle_err(struct spi_master *spi, struct spi_message *msg) switch (mas->cur_xfer_mode) { case GENI_SE_FIFO: - handle_fifo_timeout(spi, msg); + case GENI_SE_DMA: + handle_se_timeout(spi, msg); break; case GENI_GPI_DMA: handle_gpi_timeout(spi, msg); @@ -250,6 +292,8 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) } mas->cs_flag = set_flag; + /* set xfer_mode to FIFO to complete cs_done in isr */ + mas->cur_xfer_mode = GENI_SE_FIFO; reinit_completion(&mas->cs_done); if (set_flag) geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0); @@ -260,7 +304,7 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) time_left = wait_for_completion_timeout(&mas->cs_done, HZ); if (!time_left) { dev_warn(mas->dev, "Timeout setting chip select\n"); - handle_fifo_timeout(spi, NULL); + handle_se_timeout(spi, NULL); } exit: @@ -482,8 +526,12 @@ static bool geni_can_dma(struct spi_controller *ctlr, { struct spi_geni_master *mas = spi_master_get_devdata(slv->master); - /* check if dma is supported */ - return mas->cur_xfer_mode != GENI_SE_FIFO; + /* + * Return true if transfer needs to be mapped prior to + * calling transfer_one which is the case only for GPI_DMA. + * For SE_DMA mode, map/unmap is done in geni_se_*x_dma_prep. + */ + return mas->cur_xfer_mode == GENI_GPI_DMA; } static int spi_geni_prepare_message(struct spi_master *spi, @@ -494,6 +542,7 @@ static int spi_geni_prepare_message(struct spi_master *spi, switch (mas->cur_xfer_mode) { case GENI_SE_FIFO: + case GENI_SE_DMA: if (spi_geni_is_abort_still_pending(mas)) return -EBUSY; ret = setup_fifo_params(spi_msg->spi, spi); @@ -597,7 +646,7 @@ static int spi_geni_init(struct spi_geni_master *mas) break; } /* - * in case of failure to get dma channel, we can still do the + * in case of failure to get gpi dma channel, we can still do the * FIFO mode, so fallthrough */ dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n"); @@ -716,12 +765,12 @@ static void geni_spi_handle_rx(struct spi_geni_master *mas) mas->rx_rem_bytes -= rx_bytes; } -static void setup_fifo_xfer(struct spi_transfer *xfer, +static int setup_se_xfer(struct spi_transfer *xfer, struct spi_geni_master *mas, u16 mode, struct spi_master *spi) { u32 m_cmd = 0; - u32 len; + u32 len, fifo_size; struct geni_se *se = &mas->se; int ret; @@ -748,7 +797,7 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, /* Speed and bits per word can be overridden per transfer */ ret = geni_spi_set_clock_and_bw(mas, xfer->speed_hz); if (ret) - return; + return ret; mas->tx_rem_bytes = 0; mas->rx_rem_bytes = 0; @@ -772,17 +821,50 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, mas->rx_rem_bytes = xfer->len; } + /* Select transfer mode based on transfer length */ + fifo_size = mas->tx_fifo_depth * mas->fifo_width_bits / mas->cur_bits_per_word; + mas->cur_xfer_mode = (len <= fifo_size) ? GENI_SE_FIFO : GENI_SE_DMA; + geni_se_select_mode(se, mas->cur_xfer_mode); + /* * Lock around right before we start the transfer since our * interrupt could come in at any time now. */ spin_lock_irq(&mas->lock); geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION); - if (m_cmd & SPI_TX_ONLY) { + + if (mas->cur_xfer_mode == GENI_SE_DMA) { + if (m_cmd & SPI_RX_ONLY) { + ret = geni_se_rx_dma_prep(se, xfer->rx_buf, + xfer->len, &mas->rx_se_dma); + if (ret) { + dev_err(mas->dev, "Failed to setup Rx dma %d\n", ret); + mas->rx_se_dma = 0; + goto unlock_and_return; + } + } + if (m_cmd & SPI_TX_ONLY) { + ret = geni_se_tx_dma_prep(se, (void *)xfer->tx_buf, + xfer->len, &mas->tx_se_dma); + if (ret) { + dev_err(mas->dev, "Failed to setup Tx dma %d\n", ret); + mas->tx_se_dma = 0; + if (m_cmd & SPI_RX_ONLY) { + /* Unmap rx buffer if duplex transfer */ + geni_se_rx_dma_unprep(se, mas->rx_se_dma, xfer->len); + mas->rx_se_dma = 0; + } + goto unlock_and_return; + } + } + } else if (m_cmd & SPI_TX_ONLY) { if (geni_spi_handle_tx(mas)) writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG); } + +unlock_and_return: spin_unlock_irq(&mas->lock); + return ret; } static int spi_geni_transfer_one(struct spi_master *spi, @@ -790,6 +872,7 @@ static int spi_geni_transfer_one(struct spi_master *spi, struct spi_transfer *xfer) { struct spi_geni_master *mas = spi_master_get_devdata(spi); + int ret; if (spi_geni_is_abort_still_pending(mas)) return -EBUSY; @@ -798,9 +881,12 @@ static int spi_geni_transfer_one(struct spi_master *spi, if (!xfer->len) return 0; - if (mas->cur_xfer_mode == GENI_SE_FIFO) { - setup_fifo_xfer(xfer, mas, slv->mode, spi); - return 1; + if (mas->cur_xfer_mode == GENI_SE_FIFO || mas->cur_xfer_mode == GENI_SE_DMA) { + ret = setup_se_xfer(xfer, mas, slv->mode, spi); + /* SPI framework expects +ve ret code to wait for transfer complete */ + if (!ret) + ret = 1; + return ret; } return setup_gsi_xfer(xfer, mas, slv, spi); } @@ -823,39 +909,70 @@ static irqreturn_t geni_spi_isr(int irq, void *data) spin_lock(&mas->lock); - if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN)) - geni_spi_handle_rx(mas); - - if (m_irq & M_TX_FIFO_WATERMARK_EN) - geni_spi_handle_tx(mas); - - if (m_irq & M_CMD_DONE_EN) { - if (mas->cur_xfer) { + if (mas->cur_xfer_mode == GENI_SE_FIFO) { + if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN)) + geni_spi_handle_rx(mas); + + if (m_irq & M_TX_FIFO_WATERMARK_EN) + geni_spi_handle_tx(mas); + + if (m_irq & M_CMD_DONE_EN) { + if (mas->cur_xfer) { + spi_finalize_current_transfer(spi); + mas->cur_xfer = NULL; + /* + * If this happens, then a CMD_DONE came before all the + * Tx buffer bytes were sent out. This is unusual, log + * this condition and disable the WM interrupt to + * prevent the system from stalling due an interrupt + * storm. + * + * If this happens when all Rx bytes haven't been + * received, log the condition. The only known time + * this can happen is if bits_per_word != 8 and some + * registers that expect xfer lengths in num spi_words + * weren't written correctly. + */ + if (mas->tx_rem_bytes) { + writel(0, se->base + SE_GENI_TX_WATERMARK_REG); + dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n", + mas->tx_rem_bytes, mas->cur_bits_per_word); + } + if (mas->rx_rem_bytes) + dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n", + mas->rx_rem_bytes, mas->cur_bits_per_word); + } else { + complete(&mas->cs_done); + } + } + } else if (mas->cur_xfer_mode == GENI_SE_DMA) { + const struct spi_transfer *xfer = mas->cur_xfer; + u32 dma_tx_status = readl_relaxed(se->base + SE_DMA_TX_IRQ_STAT); + u32 dma_rx_status = readl_relaxed(se->base + SE_DMA_RX_IRQ_STAT); + + if (dma_tx_status) + writel(dma_tx_status, se->base + SE_DMA_TX_IRQ_CLR); + if (dma_rx_status) + writel(dma_rx_status, se->base + SE_DMA_RX_IRQ_CLR); + if (dma_tx_status & TX_DMA_DONE) + mas->tx_rem_bytes = 0; + if (dma_rx_status & RX_DMA_DONE) + mas->rx_rem_bytes = 0; + if (dma_tx_status & TX_RESET_DONE) + complete(&mas->tx_reset_done); + if (dma_rx_status & RX_RESET_DONE) + complete(&mas->rx_reset_done); + if (!mas->tx_rem_bytes && !mas->rx_rem_bytes && xfer) { + if (xfer->tx_buf && mas->tx_se_dma) { + geni_se_tx_dma_unprep(se, mas->tx_se_dma, xfer->len); + mas->tx_se_dma = 0; + } + if (xfer->rx_buf && mas->rx_se_dma) { + geni_se_rx_dma_unprep(se, mas->rx_se_dma, xfer->len); + mas->rx_se_dma = 0; + } spi_finalize_current_transfer(spi); mas->cur_xfer = NULL; - /* - * If this happens, then a CMD_DONE came before all the - * Tx buffer bytes were sent out. This is unusual, log - * this condition and disable the WM interrupt to - * prevent the system from stalling due an interrupt - * storm. - * - * If this happens when all Rx bytes haven't been - * received, log the condition. The only known time - * this can happen is if bits_per_word != 8 and some - * registers that expect xfer lengths in num spi_words - * weren't written correctly. - */ - if (mas->tx_rem_bytes) { - writel(0, se->base + SE_GENI_TX_WATERMARK_REG); - dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n", - mas->tx_rem_bytes, mas->cur_bits_per_word); - } - if (mas->rx_rem_bytes) - dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n", - mas->rx_rem_bytes, mas->cur_bits_per_word); - } else { - complete(&mas->cs_done); } } @@ -949,6 +1066,8 @@ static int spi_geni_probe(struct platform_device *pdev) init_completion(&mas->cs_done); init_completion(&mas->cancel_done); init_completion(&mas->abort_done); + init_completion(&mas->tx_reset_done); + init_completion(&mas->rx_reset_done); spin_lock_init(&mas->lock); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, 250);