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=-10.1 required=3.0 tests=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 26469C76191 for ; Mon, 15 Jul 2019 15:07:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE5BD2067C for ; Mon, 15 Jul 2019 15:07:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563203225; bh=mSly9/QB6NgeDVXk7wAa+JBqfFX3uXKExoFhgAGyqtg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hMGeDzHeu9pYhLEiQQzmDOqnOZfvnV/RamlOFKTyOtyE2SFYg0q87o/8qIP2w0gy8 kd7WsyunSBiGKXFxV4TB25Kx97GWLyjNpgW2S2L5P0oGm6+xAVbyRaehHNytWfGL9C w0YDn4PQ7sjUZXi02o7IPd/Expn9Mw/ZDok0rFF8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387863AbfGOOEL (ORCPT ); Mon, 15 Jul 2019 10:04:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:49904 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387849AbfGOOEK (ORCPT ); Mon, 15 Jul 2019 10:04:10 -0400 Received: from sasha-vm.mshome.net (unknown [73.61.17.35]) (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 C5D6C2081C; Mon, 15 Jul 2019 14:04:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563199449; bh=mSly9/QB6NgeDVXk7wAa+JBqfFX3uXKExoFhgAGyqtg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XsoFL5OvGFAxQ8K18CCWHGKNKA9hIgLro0b+0bgEgWIygcaXDM0oJSFICG3RVf7iK HIMYUSUhqfV0N4Q63YonjpER0SohrKhs5YyxUn/ycDuwyr8XgZc2MqYO2vPl26jdc+ LYmHGibWloIF9sGdm2WBZlOyJkNVznLdIb4V+YSs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Emil Renner Berthing , Mark Brown , Sasha Levin , linux-spi@vger.kernel.org, linux-rockchip@lists.infradead.org Subject: [PATCH AUTOSEL 5.1 007/219] spi: rockchip: turn down tx dma bursts Date: Mon, 15 Jul 2019 10:00:08 -0400 Message-Id: <20190715140341.6443-7-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190715140341.6443-1-sashal@kernel.org> References: <20190715140341.6443-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Emil Renner Berthing [ 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