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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A4FFC433FE for ; Tue, 9 Nov 2021 01:26:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6D774610E8 for ; Tue, 9 Nov 2021 01:26:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243950AbhKIB2j (ORCPT ); Mon, 8 Nov 2021 20:28:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:50114 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243211AbhKIBVN (ORCPT ); Mon, 8 Nov 2021 20:21:13 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1A6C761B07; Tue, 9 Nov 2021 01:08:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1636420096; bh=CaBHb5y99m3Qd8zy0Hrg4tV9zHkZUHAhNx8botNcBZM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eLuviWrf+RMX8kA60M2ZkPA+yAp7iTsdLwEVsnSGlf8H8Mhtwfgn3u+XBxVlr8jEc VfFpY97T5SLRmVn2Uu7zMN5fPfvXe4ZMWlLRwY/rH9/aJTWm7/7ylvcmXJnwWq5mT4 8AIg88WqOSQCGur1kTteyUZvMYNimtk5Hmp0o6UCyVE6bvzcP0omKL0+jeVqAMewh3 FbeIgJApS4duQuSxL8sUDc62AlMSOkB3P0UnxMLLazERy4lVTT92pmXFDxWsxWBqu8 bbAStyqDrbHvjer+LIao09JWtF1XPrgRLBAsMM7LHFkTvL4TLWjIiHfDuD/ahrzaKW zOG9hzU9K3AqA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Aleksander Jan Bajkowski , "David S . Miller" , Sasha Levin , john@phrozen.org, tsbogend@alpha.franken.de, maz@kernel.org, hauke@hauke-m.de, linux-mips@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 04/33] MIPS: lantiq: dma: add small delay after reset Date: Mon, 8 Nov 2021 20:07:38 -0500 Message-Id: <20211109010807.1191567-4-sashal@kernel.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211109010807.1191567-1-sashal@kernel.org> References: <20211109010807.1191567-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Aleksander Jan Bajkowski [ Upstream commit c12aa581f6d5e80c3c3675ab26a52c2b3b62f76e ] Reading the DMA registers immediately after the reset causes Data Bus Error. Adding a small delay fixes this issue. Signed-off-by: Aleksander Jan Bajkowski Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- arch/mips/lantiq/xway/dma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/mips/lantiq/xway/dma.c b/arch/mips/lantiq/xway/dma.c index cef811755123f..d89a9bcf92c85 100644 --- a/arch/mips/lantiq/xway/dma.c +++ b/arch/mips/lantiq/xway/dma.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -232,6 +233,8 @@ ltq_dma_init(struct platform_device *pdev) clk_enable(clk); ltq_dma_w32_mask(0, DMA_RESET, LTQ_DMA_CTRL); + usleep_range(1, 10); + /* disable all interrupts */ ltq_dma_w32(0, LTQ_DMA_IRNEN); -- 2.33.0