From patchwork Fri Feb 11 03:49:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jon Lin X-Patchwork-Id: 12742814 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 9C410C433EF for ; Fri, 11 Feb 2022 03:49:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236979AbiBKDts (ORCPT ); Thu, 10 Feb 2022 22:49:48 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:36552 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236624AbiBKDtr (ORCPT ); Thu, 10 Feb 2022 22:49:47 -0500 Received: from mail-m17664.qiye.163.com (mail-m17664.qiye.163.com [59.111.176.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A617855BE; Thu, 10 Feb 2022 19:49:46 -0800 (PST) Received: from localhost.localdomain (unknown [58.22.7.114]) by mail-m17664.qiye.163.com (Hmail) with ESMTPA id D6F9E140149; Fri, 11 Feb 2022 11:49:44 +0800 (CST) From: Jon Lin To: broonie@kernel.org Cc: heiko@sntech.de, linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Jon Lin Subject: [RFC PATCH v1 1/6] spi: rockchip: Stop spi slave dma receiver when cs inactive Date: Fri, 11 Feb 2022 11:49:33 +0800 Message-Id: <20220211034938.25097-2-jon.lin@rock-chips.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220211034938.25097-1-jon.lin@rock-chips.com> References: <20220211034938.25097-1-jon.lin@rock-chips.com> X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgPGg8OCBgUHx5ZQUlOS1dZCBgUCR5ZQVlLVUtZV1 kWDxoPAgseWUFZKDYvK1lXWShZQUhPN1dZLVlBSVdZDwkaFQgSH1lBWRpOHhpWTkNPGhpPHx1ITk pDVRMBExYaEhckFA4PWVdZFhoPEhUdFFlBWVVLWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6PzI6MSo6LD4DDh46CEg6DSsU LQEwFDRVSlVKTU9PTk5KSENOSUJNVTMWGhIXVREUFVUXEhU7CRQYEFYYExILCFUYFBZFWVdZEgtZ QVlOQ1VJSVVMVUpKT1lXWQgBWUFMTE9INwY+ X-HM-Tid: 0a7ee6e6afccda2fkuwsd6f9e140149 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The spi which's version is higher than ver 2 will automatically enable this feature. If the length of master transmission is uncertain, the RK spi slave is better to automatically stop after cs inactive instead of waiting for xfer_completion forever. Signed-off-by: Jon Lin --- drivers/spi/spi-rockchip.c | 85 ++++++++++++++++++++++++++++++++++---- 1 file changed, 77 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 553b6b9d0222..7ac07569e103 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -133,7 +133,8 @@ #define INT_TF_OVERFLOW (1 << 1) #define INT_RF_UNDERFLOW (1 << 2) #define INT_RF_OVERFLOW (1 << 3) -#define INT_RF_FULL (1 << 4) +#define INT_RF_FULL (1 << 4) +#define INT_CS_INACTIVE (1 << 6) /* Bit fields in ICR, 4bit */ #define ICR_MASK 0x0f @@ -194,6 +195,8 @@ struct rockchip_spi { bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM]; bool slave_abort; + bool cs_inactive; /* spi slave tansmition stop when cs inactive */ + struct spi_transfer *xfer; /* Store xfer temporarily */ }; static inline void spi_enable_chip(struct rockchip_spi *rs, bool enable) @@ -343,6 +346,15 @@ static irqreturn_t rockchip_spi_isr(int irq, void *dev_id) struct spi_controller *ctlr = dev_id; struct rockchip_spi *rs = spi_controller_get_devdata(ctlr); + /* When int_cs_inactive comes, spi slave abort */ + if (rs->cs_inactive && readl_relaxed(rs->regs + ROCKCHIP_SPI_IMR) & INT_CS_INACTIVE) { + ctlr->slave_abort(ctlr); + writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR); + writel_relaxed(0xffffffff, rs->regs + ROCKCHIP_SPI_ICR); + + return IRQ_HANDLED; + } + if (rs->tx_left) rockchip_spi_pio_writer(rs); @@ -350,6 +362,7 @@ static irqreturn_t rockchip_spi_isr(int irq, void *dev_id) if (!rs->rx_left) { spi_enable_chip(rs, false); writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR); + writel_relaxed(0xffffffff, rs->regs + ROCKCHIP_SPI_ICR); spi_finalize_current_transfer(ctlr); } @@ -357,14 +370,18 @@ static irqreturn_t rockchip_spi_isr(int irq, void *dev_id) } static int rockchip_spi_prepare_irq(struct rockchip_spi *rs, - struct spi_transfer *xfer) + struct spi_controller *ctlr, + struct spi_transfer *xfer) { rs->tx = xfer->tx_buf; rs->rx = xfer->rx_buf; rs->tx_left = rs->tx ? xfer->len / rs->n_bytes : 0; rs->rx_left = xfer->len / rs->n_bytes; - writel_relaxed(INT_RF_FULL, rs->regs + ROCKCHIP_SPI_IMR); + if (rs->cs_inactive) + writel_relaxed(INT_RF_FULL | INT_CS_INACTIVE, rs->regs + ROCKCHIP_SPI_IMR); + else + writel_relaxed(INT_RF_FULL, rs->regs + ROCKCHIP_SPI_IMR); spi_enable_chip(rs, true); if (rs->tx_left) @@ -383,6 +400,9 @@ static void rockchip_spi_dma_rxcb(void *data) if (state & TXDMA && !rs->slave_abort) return; + if (rs->cs_inactive) + writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR); + spi_enable_chip(rs, false); spi_finalize_current_transfer(ctlr); } @@ -423,14 +443,16 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, atomic_set(&rs->state, 0); + rs->tx = xfer->tx_buf; + rs->rx = xfer->rx_buf; + rxdesc = NULL; if (xfer->rx_buf) { struct dma_slave_config rxconf = { .direction = DMA_DEV_TO_MEM, .src_addr = rs->dma_addr_rx, .src_addr_width = rs->n_bytes, - .src_maxburst = rockchip_spi_calc_burst_size(xfer->len / - rs->n_bytes), + .src_maxburst = rockchip_spi_calc_burst_size(xfer->len / rs->n_bytes), }; dmaengine_slave_config(ctlr->dma_rx, &rxconf); @@ -474,10 +496,13 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, /* rx must be started before tx due to spi instinct */ if (rxdesc) { atomic_or(RXDMA, &rs->state); - dmaengine_submit(rxdesc); + ctlr->dma_rx->cookie = dmaengine_submit(rxdesc); dma_async_issue_pending(ctlr->dma_rx); } + if (rs->cs_inactive) + writel_relaxed(INT_CS_INACTIVE, rs->regs + ROCKCHIP_SPI_IMR); + spi_enable_chip(rs, true); if (txdesc) { @@ -584,7 +609,46 @@ static size_t rockchip_spi_max_transfer_size(struct spi_device *spi) static int rockchip_spi_slave_abort(struct spi_controller *ctlr) { struct rockchip_spi *rs = spi_controller_get_devdata(ctlr); + u32 rx_fifo_left; + struct dma_tx_state state; + enum dma_status status; + + /* Get current dma rx point */ + if (atomic_read(&rs->state) & RXDMA) { + dmaengine_pause(ctlr->dma_rx); + status = dmaengine_tx_status(ctlr->dma_rx, ctlr->dma_rx->cookie, &state); + dmaengine_terminate_sync(ctlr->dma_rx); + atomic_set(&rs->state, 0); + if (status == DMA_ERROR) { + rs->rx = rs->xfer->rx_buf; + rs->xfer->len = 0; + rx_fifo_left = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR); + for (; rx_fifo_left; rx_fifo_left--) + readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR); + goto out; + } else { + rs->rx += rs->xfer->len - rs->n_bytes * state.residue; + } + } + + /* Get the valid data left in rx fifo and set rs->xfer->len real rx size */ + if (rs->rx) { + rx_fifo_left = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR); + for (; rx_fifo_left; rx_fifo_left--) { + u32 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR); + + if (rs->n_bytes == 1) + *(u8 *)rs->rx = (u8)rxw; + else + *(u16 *)rs->rx = (u16)rxw; + rs->rx += rs->n_bytes; + } + rs->xfer->len = (unsigned int)(rs->rx - rs->xfer->rx_buf); + } + +out: + spi_enable_chip(rs, false); rs->slave_abort = true; spi_finalize_current_transfer(ctlr); @@ -620,7 +684,7 @@ static int rockchip_spi_transfer_one( } rs->n_bytes = xfer->bits_per_word <= 8 ? 1 : 2; - + rs->xfer = xfer; use_dma = ctlr->can_dma ? ctlr->can_dma(ctlr, spi, xfer) : false; ret = rockchip_spi_config(rs, spi, xfer, use_dma, ctlr->slave); @@ -630,7 +694,7 @@ static int rockchip_spi_transfer_one( if (use_dma) return rockchip_spi_prepare_dma(rs, ctlr, xfer); - return rockchip_spi_prepare_irq(rs, xfer); + return rockchip_spi_prepare_irq(rs, ctlr, xfer); } static bool rockchip_spi_can_dma(struct spi_controller *ctlr, @@ -808,8 +872,13 @@ static int rockchip_spi_probe(struct platform_device *pdev) switch (readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION)) { case ROCKCHIP_SPI_VER2_TYPE2: ctlr->mode_bits |= SPI_CS_HIGH; + if (ctlr->can_dma && slave_mode) + rs->cs_inactive = true; + else + rs->cs_inactive = false; break; default: + rs->cs_inactive = false; break; }