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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 AA38AC76186 for ; Wed, 24 Jul 2019 19:43:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79C9F2083B for ; Wed, 24 Jul 2019 19:43:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563997411; bh=W8I/0sEJvvMpi4Y8zI8egnQo6HPoOJCWtCwvazHA5E0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2Sc+nWLpEZQCDUkUUc3x/NhlNcyfLFde3455M5B4rYytZJ591FChRKpvWGWiOcvlH SWvOV+0W7F7qBk/tR34g8e8MwWUqB0HYLm+U5C47guSuj508Y6rSPGB10nTJkPRUCG foBo35HbM6lqYGtF110lgdzQXA/jzUG9seBdc/is= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390559AbfGXTn0 (ORCPT ); Wed, 24 Jul 2019 15:43:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:45606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390073AbfGXTnY (ORCPT ); Wed, 24 Jul 2019 15:43:24 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2E65922BE9; Wed, 24 Jul 2019 19:43:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563997403; bh=W8I/0sEJvvMpi4Y8zI8egnQo6HPoOJCWtCwvazHA5E0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fpy23tybGROEXUwmyAKtEJOg1A2Cyn64BR25Z4/LCK1y41xw5Vb8Igzj1ATiSRHQ3 ftEcxdEmLgtZfZ0aXkdCiJfffNCB2gccbY9/LTFpRKj8D5ZopGzaKewyHPWagSqnrw fd4UUzoC/faMg6whwFnu6AuoeoR8zAVHTPDCzRkU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Emil Renner Berthing , Mark Brown , Sasha Levin Subject: [PATCH 5.1 012/371] spi: rockchip: turn down tx dma bursts Date: Wed, 24 Jul 2019 21:16:04 +0200 Message-Id: <20190724191725.426507132@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190724191724.382593077@linuxfoundation.org> References: <20190724191724.382593077@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 47300728fb213486a830565d2af49da967c9d16a ] This fixes tx and bi-directional dma transfers on rk3399-gru-kevin. It seems the SPI fifo must have room for 2 bursts when the dma_tx_req signal is generated or it might skip some words. This in turn makes the rx dma channel never complete for bi-directional transfers. Fix it by setting tx burst length to fifo_len / 4 and the dma watermark to fifo_len / 2. However the rk3399 TRM says (sic): "DMAC support incrementing-address burst and fixed-address burst. But in the case of access SPI and UART at byte or halfword size, DMAC only support fixed-address burst and the address must be aligned to word." So this relies on fifo_len being a multiple of 16 such that the burst length (= fifo_len / 4) is a multiple of 4 and the addresses will be word-aligned. Fixes: dcfc861d24ec ("spi: rockchip: adjust dma watermark and burstlen") Signed-off-by: Emil Renner Berthing Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-rockchip.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 3912526ead66..19f6a76f1c07 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -425,7 +425,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, .direction = DMA_MEM_TO_DEV, .dst_addr = rs->dma_addr_tx, .dst_addr_width = rs->n_bytes, - .dst_maxburst = rs->fifo_len / 2, + .dst_maxburst = rs->fifo_len / 4, }; dmaengine_slave_config(master->dma_tx, &txconf); @@ -526,7 +526,7 @@ static void rockchip_spi_config(struct rockchip_spi *rs, else writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR); - writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_DMATDLR); + writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR); writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR); writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR); -- 2.20.1