From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 178FCC433E1 for ; Mon, 24 Aug 2020 17:05:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA08D206F0 for ; Mon, 24 Aug 2020 17:05:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598288752; bh=gU9+oL8QuHBfkGQPrxNxOBrABrrUSMiM7oT+OpPKktw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FMovw4z0CFFWB4uDIiJuB0/UoaYql7tGwcipvo2WvXdS6NIbrXIPdIhqh8GDWjpEr OoA57gyLP3AltmL1oXnE2xPR1IH7dG/YFsUpnZcBG9xUr8l5BpXJU13XfUI4j8OM2o hOIW9s7q6TwuXbAPYFFLOibjmY3t+AawpJPdA0Lc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727075AbgHXRFs (ORCPT ); Mon, 24 Aug 2020 13:05:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:41428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728450AbgHXQib (ORCPT ); Mon, 24 Aug 2020 12:38:31 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5F1D722E01; Mon, 24 Aug 2020 16:38:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598287086; bh=gU9+oL8QuHBfkGQPrxNxOBrABrrUSMiM7oT+OpPKktw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X8jLZgWqfBnob1FnRqAp3CXS59pdh1DdoSKUFpeR3qgaKZFyH0AJ+Eci2Rxox45QQ 6XBDfysh1nf/xemGCw3o5lLW+k4DNrSP7SRISIXJJiEgoPtQE8ZlTq8lx6zwaHOLTH 5lNcOEJs9HqpnjHkrJxYJbjmqIpPSnty0yGXRuLw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Amelie Delaunay , Alain Volmat , Mark Brown , Sasha Levin , linux-spi@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.4 11/38] spi: stm32: fix fifo threshold level in case of short transfer Date: Mon, 24 Aug 2020 12:37:23 -0400 Message-Id: <20200824163751.606577-11-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200824163751.606577-1-sashal@kernel.org> References: <20200824163751.606577-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Amelie Delaunay [ Upstream commit 3373e9004acc0603242622b4378c64bc01d21b5f ] When transfer is shorter than half of the fifo, set the data packet size up to transfer size instead of up to half of the fifo. Check also that threshold is set at least to 1 data frame. Signed-off-by: Amelie Delaunay Signed-off-by: Alain Volmat Link: https://lore.kernel.org/r/1597043558-29668-3-git-send-email-alain.volmat@st.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-stm32.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index cb54471456145..264a7e937f9eb 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -468,20 +468,27 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz, /** * stm32h7_spi_prepare_fthlv - Determine FIFO threshold level * @spi: pointer to the spi controller data structure + * @xfer_len: length of the message to be transferred */ -static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi) +static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi, u32 xfer_len) { - u32 fthlv, half_fifo; + u32 fthlv, half_fifo, packet; /* data packet should not exceed 1/2 of fifo space */ half_fifo = (spi->fifo_size / 2); + /* data_packet should not exceed transfer length */ + if (half_fifo > xfer_len) + packet = xfer_len; + else + packet = half_fifo; + if (spi->cur_bpw <= 8) - fthlv = half_fifo; + fthlv = packet; else if (spi->cur_bpw <= 16) - fthlv = half_fifo / 2; + fthlv = packet / 2; else - fthlv = half_fifo / 4; + fthlv = packet / 4; /* align packet size with data registers access */ if (spi->cur_bpw > 8) @@ -489,6 +496,9 @@ static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi) else fthlv -= (fthlv % 4); /* multiple of 4 */ + if (!fthlv) + fthlv = 1; + return fthlv; } @@ -1395,7 +1405,7 @@ static void stm32h7_spi_set_bpw(struct stm32_spi *spi) cfg1_setb |= (bpw << STM32H7_SPI_CFG1_DSIZE_SHIFT) & STM32H7_SPI_CFG1_DSIZE; - spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi); + spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi, spi->cur_xferlen); fthlv = spi->cur_fthlv - 1; cfg1_clrb |= STM32H7_SPI_CFG1_FTHLV; @@ -1581,6 +1591,8 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi, spin_lock_irqsave(&spi->lock, flags); + spi->cur_xferlen = transfer->len; + if (spi->cur_bpw != transfer->bits_per_word) { spi->cur_bpw = transfer->bits_per_word; spi->cfg->set_bpw(spi); @@ -1628,8 +1640,6 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi, goto out; } - spi->cur_xferlen = transfer->len; - dev_dbg(spi->dev, "transfer communication mode set to %d\n", spi->cur_comm); dev_dbg(spi->dev, -- 2.25.1