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=-9.1 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 234BEC282DD for ; Wed, 22 May 2019 19:33:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5CC22081C for ; Wed, 22 May 2019 19:33:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558553635; bh=TtZxRTTPiWvnlFqdm9fT0u4QdkJyzZY3C89GNM1Bbdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=p0pjf7pAKJxupzddgdZLeKF3HTiBAkGLujSIBRCf9LKBKoImjccPuLPMEmiGnWlaA fxpCSer+ZyQ+59d+w/KJ3cFA1BjQG3LB/6jFpjmsJ9Q8S8+niO94qmZ0fnbSDJmztN htI4Em1v8pK3uVt7AsCLxMUnqxAsc7s7ikS5nwaU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733287AbfEVTdy (ORCPT ); Wed, 22 May 2019 15:33:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:55306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387599AbfEVTbn (ORCPT ); Wed, 22 May 2019 15:31:43 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 4C85C20879; Wed, 22 May 2019 19:31:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558553502; bh=TtZxRTTPiWvnlFqdm9fT0u4QdkJyzZY3C89GNM1Bbdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QjmGVoibD5N5pdLdY5G9VAsBiQsDSO+GNPSieiYr6o1idPSkAWHKJbmnyP9jS7cDT LRV0NrWfweypluFBWJVNRN13Uae6Zm7iyRMAwbFpdJk1BK9M+bifScdEy48oU5Fpku UDn6LJvp8CirOuIL/SIj7jGJfVWRv4f7Y4PO15Bg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sugar Zhang , Vinod Koul , Sasha Levin , dmaengine@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 10/92] dmaengine: pl330: _stop: clear interrupt status Date: Wed, 22 May 2019 15:30:05 -0400 Message-Id: <20190522193127.27079-10-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190522193127.27079-1-sashal@kernel.org> References: <20190522193127.27079-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sugar Zhang [ Upstream commit 2da254cc7908105a60a6bb219d18e8dced03dcb9 ] This patch kill instructs the DMAC to immediately terminate execution of a thread. and then clear the interrupt status, at last, stop generating interrupts for DMA_SEV. to guarantee the next dma start is clean. otherwise, one interrupt maybe leave to next start and make some mistake. we can reporduce the problem as follows: DMASEV: modify the event-interrupt resource, and if the INTEN sets function as interrupt, the DMAC will set irq HIGH to generate interrupt. write INTCLR to clear interrupt. DMA EXECUTING INSTRUCTS DMA TERMINATE | | | | ... _stop | | | spin_lock_irqsave DMASEV | | | | mask INTEN | | | DMAKILL | | | spin_unlock_irqrestore in above case, a interrupt was left, and if we unmask INTEN, the DMAC will set irq HIGH to generate interrupt. to fix this, do as follows: DMA EXECUTING INSTRUCTS DMA TERMINATE | | | | ... _stop | | | spin_lock_irqsave DMASEV | | | | DMAKILL | | | clear INTCLR | mask INTEN | | | spin_unlock_irqrestore Signed-off-by: Sugar Zhang Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/pl330.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 95619ee33112c..799c182c3eacc 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -1006,6 +1006,7 @@ static void _stop(struct pl330_thread *thrd) { void __iomem *regs = thrd->dmac->base; u8 insn[6] = {0, 0, 0, 0, 0, 0}; + u32 inten = readl(regs + INTEN); if (_state(thrd) == PL330_STATE_FAULT_COMPLETING) UNTIL(thrd, PL330_STATE_FAULTING | PL330_STATE_KILLING); @@ -1018,10 +1019,13 @@ static void _stop(struct pl330_thread *thrd) _emit_KILL(0, insn); - /* Stop generating interrupts for SEV */ - writel(readl(regs + INTEN) & ~(1 << thrd->ev), regs + INTEN); - _execute_DBGINSN(thrd, insn, is_manager(thrd)); + + /* clear the event */ + if (inten & (1 << thrd->ev)) + writel(1 << thrd->ev, regs + INTCLR); + /* Stop generating interrupts for SEV */ + writel(inten & ~(1 << thrd->ev), regs + INTEN); } /* Start doing req 'idx' of thread 'thrd' */ -- 2.20.1