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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADDE4CDB465 for ; Mon, 16 Oct 2023 09:02:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233242AbjJPJCZ (ORCPT ); Mon, 16 Oct 2023 05:02:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233409AbjJPJCG (ORCPT ); Mon, 16 Oct 2023 05:02:06 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E6938F9 for ; Mon, 16 Oct 2023 02:02:03 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B25AC433C7; Mon, 16 Oct 2023 09:02:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1697446923; bh=aSPR0PcbeXtXpgBTBKqkszRniGlFSKCIf341qGi0pKs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Oi7bMgfw9gWWOFno1zMIWPfXSvbdkZSRWPa9pRqKMdcSyqFFt2q5j4vtRDcSxF3SO /MEzWQJVv5ljiSol/8D5BlGhKyIeasHBrSRu4TMsdSBofAePzzOHs8RajRYeuTSxF6 bsv0YrWfAEgJAcXOk3MplBc4394oueBCNcEICNbw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Amelie Delaunay , Vinod Koul Subject: [PATCH 6.1 070/131] dmaengine: stm32-dma: fix residue in case of MDMA chaining Date: Mon, 16 Oct 2023 10:40:53 +0200 Message-ID: <20231016084001.804115920@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231016084000.050926073@linuxfoundation.org> References: <20231016084000.050926073@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Amelie Delaunay commit 67e13e89742c3b21ce177f612bf9ef32caae6047 upstream. In case of MDMA chaining, DMA is configured in Double-Buffer Mode (DBM) with two periods, but if transfer has been prepared with _prep_slave_sg(), the transfer is not marked cyclic (=!chan->desc->cyclic). However, as DBM is activated for MDMA chaining, residue computation must take into account cyclic constraints. With only two periods in MDMA chaining, and no update due to Transfer Complete interrupt masked, n_sg is always 0. If DMA current memory address (depending on SxCR.CT and SxM0AR/SxM1AR) does not correspond, it means n_sg should be increased. Then, the residue of the current period is the one read from SxNDTR and should not be overwritten with the full period length. Fixes: 723795173ce1 ("dmaengine: stm32-dma: add support to trigger STM32 MDMA") Signed-off-by: Amelie Delaunay Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231004155024.2609531-2-amelie.delaunay@foss.st.com Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/stm32-dma.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index 7427acc82259..0b30151fb45c 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -1389,11 +1389,12 @@ static size_t stm32_dma_desc_residue(struct stm32_dma_chan *chan, residue = stm32_dma_get_remaining_bytes(chan); - if (chan->desc->cyclic && !stm32_dma_is_current_sg(chan)) { + if ((chan->desc->cyclic || chan->trig_mdma) && !stm32_dma_is_current_sg(chan)) { n_sg++; if (n_sg == chan->desc->num_sgs) n_sg = 0; - residue = sg_req->len; + if (!chan->trig_mdma) + residue = sg_req->len; } /* @@ -1403,7 +1404,7 @@ static size_t stm32_dma_desc_residue(struct stm32_dma_chan *chan, * residue = remaining bytes from NDTR + remaining * periods/sg to be transferred */ - if (!chan->desc->cyclic || n_sg != 0) + if ((!chan->desc->cyclic && !chan->trig_mdma) || n_sg != 0) for (i = n_sg; i < desc->num_sgs; i++) residue += desc->sg_req[i].len; -- 2.42.0