From patchwork Wed Aug 29 21:32:47 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Cercueil X-Patchwork-Id: 10580979 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0A8D1139B for ; Wed, 29 Aug 2018 21:35:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EE43C2BB6B for ; Wed, 29 Aug 2018 21:35:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E24012BB73; Wed, 29 Aug 2018 21:35:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6AF732BB6D for ; Wed, 29 Aug 2018 21:35:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727042AbeH3Bdn (ORCPT ); Wed, 29 Aug 2018 21:33:43 -0400 Received: from outils.crapouillou.net ([89.234.176.41]:53184 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727272AbeH3Bb7 (ORCPT ); Wed, 29 Aug 2018 21:31:59 -0400 From: Paul Cercueil To: Vinod Koul , Ralf Baechle , Paul Burton Cc: od@zcrc.me, dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, Paul Cercueil Subject: [PATCH v5 05/18] dmaengine: dma-jz4780: Use 4-word descriptors Date: Wed, 29 Aug 2018 23:32:47 +0200 Message-Id: <20180829213300.22829-6-paul@crapouillou.net> In-Reply-To: <20180829213300.22829-1-paul@crapouillou.net> References: <20180829213300.22829-1-paul@crapouillou.net> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1535578390; bh=m5hvUX0ZsROwsODCNS9h1ziPLLTBGgiDkbgfAhgKwM4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=tisaK66E4/lGcxd5Brups4weiHuke6WabWk1ToYIz4dL+xkmurWBmZgYmSrbdspeH4Cwthhp8uMBWRiGr0MypjfuFofyJtzs6Fcl7A5xHMf0WTUr+wWTOJilbnh8/HL+oJgVsBoo8F05kFg/SNSVNodgablFvH19W2gO0TLkdks= Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The only information we use in the 8-word version of the hardware DMA descriptor that is not present in the 4-word version is the transfer type, aka. the ID of the source or recipient device. Since the transfer type will never change for a DMA channel in use, we can just set it once for all in the corresponding DMA register before starting any transfer. This has several benefits: * the driver will handle twice as many hardware DMA descriptors; * the driver is closer to support the JZ4740, which only supports 4-word hardware DMA descriptors; * the JZ4770 SoC needs the transfer type to be set in the corresponding DMA register anyway, even if 8-word descriptors are in use. Signed-off-by: Paul Cercueil Tested-by: Mathieu Malaterre Reviewed-by: PrasannaKumar Muralidharan --- Notes: v2: No change v3: No change v4: No change v5: No change drivers/dma/dma-jz4780.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c index adf4d5efced6..7683de9fb9ee 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -95,17 +95,12 @@ * @dtc: transfer count (number of blocks of the transfer size specified in DCM * to transfer) in the low 24 bits, offset of the next descriptor from the * descriptor base address in the upper 8 bits. - * @sd: target/source stride difference (in stride transfer mode). - * @drt: request type */ struct jz4780_dma_hwdesc { uint32_t dcm; uint32_t dsa; uint32_t dta; uint32_t dtc; - uint32_t sd; - uint32_t drt; - uint32_t reserved[2]; }; /* Size of allocations for hardware descriptor blocks. */ @@ -281,7 +276,6 @@ static int jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan, desc->dcm = JZ_DMA_DCM_SAI; desc->dsa = addr; desc->dta = config->dst_addr; - desc->drt = jzchan->transfer_type; width = config->dst_addr_width; maxburst = config->dst_maxburst; @@ -289,7 +283,6 @@ static int jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan, desc->dcm = JZ_DMA_DCM_DAI; desc->dsa = config->src_addr; desc->dta = addr; - desc->drt = jzchan->transfer_type; width = config->src_addr_width; maxburst = config->src_maxburst; @@ -434,9 +427,10 @@ static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_memcpy( tsz = jz4780_dma_transfer_size(dest | src | len, &jzchan->transfer_shift); + jzchan->transfer_type = JZ_DMA_DRT_AUTO; + desc->desc[0].dsa = src; desc->desc[0].dta = dest; - desc->desc[0].drt = JZ_DMA_DRT_AUTO; desc->desc[0].dcm = JZ_DMA_DCM_TIE | JZ_DMA_DCM_SAI | JZ_DMA_DCM_DAI | tsz << JZ_DMA_DCM_TSZ_SHIFT | JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_SP_SHIFT | @@ -491,9 +485,12 @@ static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) (jzchan->curr_hwdesc + 1) % jzchan->desc->count; } - /* Use 8-word descriptors. */ - jz4780_dma_chn_writel(jzdma, jzchan->id, - JZ_DMA_REG_DCS, JZ_DMA_DCS_DES8); + /* Use 4-word descriptors. */ + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); + + /* Set transfer type. */ + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DRT, + jzchan->transfer_type); /* Write descriptor address and initiate descriptor fetch. */ desc_phys = jzchan->desc->desc_phys + @@ -503,7 +500,7 @@ static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) /* Enable the channel. */ jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, - JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE); + JZ_DMA_DCS_CTE); } static void jz4780_dma_issue_pending(struct dma_chan *chan)