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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 70134C6778C for ; Tue, 3 Jul 2018 12:32:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2B4422084D for ; Tue, 3 Jul 2018 12:32:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="nrvxwJkp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B4422084D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=crapouillou.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753383AbeGCMcf (ORCPT ); Tue, 3 Jul 2018 08:32:35 -0400 Received: from outils.crapouillou.net ([89.234.176.41]:46646 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752612AbeGCMcd (ORCPT ); Tue, 3 Jul 2018 08:32:33 -0400 From: Paul Cercueil To: Vinod Koul , Rob Herring , Mark Rutland , Ralf Baechle , Paul Burton , James Hogan , Zubair Lutfullah Kakakhel Cc: Mathieu Malaterre , Daniel Silsby , dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, Paul Cercueil Subject: [PATCH 03/14] dmaengine: dma-jz4780: Use 4-word descriptors Date: Tue, 3 Jul 2018 14:32:03 +0200 Message-Id: <20180703123214.23090-4-paul@crapouillou.net> In-Reply-To: <20180703123214.23090-1-paul@crapouillou.net> References: <20180703123214.23090-1-paul@crapouillou.net> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1530621151; bh=x2w6U476zZP4+jCoJbedcXjYBSa/JX+w8NhUn/Xnrkw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=nrvxwJkpxw+mFiViEuLIYEvOOgjZbOfzTrXJ6uf4tQkbsHOs1mfm/lcTUYYcamlYyrtsEut+EzUG6vIBhMPMwk1d9mpEXPbAnUVUpbJ2rlvpbLuV9hYhZAcj9MGfpffvb6KKBld9K50MbFRxn/0O++T4PgZST7Pg5tDiD7m742Q= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 4d234caf5d62..cd2cd70fd843 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -93,17 +93,12 @@ * @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. */ @@ -280,7 +275,6 @@ 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; @@ -288,7 +282,6 @@ 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; @@ -433,9 +426,10 @@ 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 | @@ -490,9 +484,12 @@ 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 + @@ -502,7 +499,7 @@ 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) -- 2.18.0