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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 C5CF8C433E2 for ; Mon, 20 Jul 2020 16:25:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4BE520773 for ; Mon, 20 Jul 2020 16:25:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595262324; bh=MjQVEo8ePfmHAxMzEUEPB8j9rECsoTukm0HF3RCe50g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gBfx+bhl9oAIW11k2EKDBB8r0+QZjyIvRuKax4+ZGVzdijUzyS+KjMaZWXtlBjXFk o79VdP0fMljmZbYMYmLMfr98L5JpRSbpVgKIbQuqwNkQU7lJKyqFM9HUEbZL3ejL9v 5L6fFcioAj6WKTyxIskbkEL5nGwaf6eILGfM5PQQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732558AbgGTQBp (ORCPT ); Mon, 20 Jul 2020 12:01:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:35044 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731433AbgGTQBe (ORCPT ); Mon, 20 Jul 2020 12:01:34 -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 AFE2620672; Mon, 20 Jul 2020 16:01:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595260894; bh=MjQVEo8ePfmHAxMzEUEPB8j9rECsoTukm0HF3RCe50g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wz5W7fq2gs/jK2vV41lfgPCmSdruu+SIBu5Xx+Ydgo9ZrgewfWtQvzLvW5oIq9jyE 7d7f4qMbcearp+CIAZSs7L/PRD6t9gOoCmB4VuxpSuEiCtGiQYyqAdnf7yD8+5iS4v w6AEN5BLOvzcQqSSINCXHhTvr8R9zzhs0dAAHrSs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tsuchiya Yuto , Andy Shevchenko , Viresh Kumar , Vinod Koul , Sasha Levin Subject: [PATCH 5.4 103/215] dmaengine: dw: Initialize channel before each transfer Date: Mon, 20 Jul 2020 17:36:25 +0200 Message-Id: <20200720152825.107548982@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152820.122442056@linuxfoundation.org> References: <20200720152820.122442056@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andy Shevchenko [ Upstream commit 99ba8b9b0d9780e9937eb1d488d120e9e5c2533d ] In some cases DMA can be used only with a consumer which does runtime power management and on the platforms, that have DMA auto power gating logic (see comments in the drivers/acpi/acpi_lpss.c), may result in DMA losing its context. Simple mitigation of this issue is to initialize channel each time the consumer initiates a transfer. Fixes: cfdf5b6cc598 ("dw_dmac: add support for Lynxpoint DMA controllers") Reported-by: Tsuchiya Yuto Signed-off-by: Andy Shevchenko Acked-by: Viresh Kumar BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206403 Link: https://lore.kernel.org/r/20200705115620.51929-1-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/dw/core.c | 12 ------------ 1 file changed, 12 deletions(-) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 21cb2a58dbd29..a1b56f52db2f2 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -118,16 +118,11 @@ static void dwc_initialize(struct dw_dma_chan *dwc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); - if (test_bit(DW_DMA_IS_INITIALIZED, &dwc->flags)) - return; - dw->initialize_chan(dwc); /* Enable interrupts */ channel_set_bit(dw, MASK.XFER, dwc->mask); channel_set_bit(dw, MASK.ERROR, dwc->mask); - - set_bit(DW_DMA_IS_INITIALIZED, &dwc->flags); } /*----------------------------------------------------------------------*/ @@ -954,8 +949,6 @@ static void dwc_issue_pending(struct dma_chan *chan) void do_dw_dma_off(struct dw_dma *dw) { - unsigned int i; - dma_writel(dw, CFG, 0); channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); @@ -966,9 +959,6 @@ void do_dw_dma_off(struct dw_dma *dw) while (dma_readl(dw, CFG) & DW_CFG_DMA_EN) cpu_relax(); - - for (i = 0; i < dw->dma.chancnt; i++) - clear_bit(DW_DMA_IS_INITIALIZED, &dw->chan[i].flags); } void do_dw_dma_on(struct dw_dma *dw) @@ -1032,8 +1022,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan) /* Clear custom channel configuration */ memset(&dwc->dws, 0, sizeof(struct dw_dma_slave)); - clear_bit(DW_DMA_IS_INITIALIZED, &dwc->flags); - /* Disable interrupts */ channel_clear_bit(dw, MASK.XFER, dwc->mask); channel_clear_bit(dw, MASK.BLOCK, dwc->mask); -- 2.25.1