From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [PATCH] dmaengine: qcom_hidma: release the descriptor before the callback Date: Fri, 19 Aug 2016 11:22:52 +0530 Message-ID: <20160819055252.GT9681@localhost> References: <20160804144003.GV1041@n2100.armlinux.org.uk> <20160808090203.GY9681@localhost> <21475c6e-a5f8-5125-3998-f3995ce67c4d@codeaurora.org> <20160810172805.GH9681@localhost> <20160819024853.GR9681@localhost> <8c096fee-9749-a7df-7e04-25d21c0ea9ac@codeaurora.org> <20160819034249.GS9681@localhost> <3592cfe2-a563-7c26-9a9e-925051cc1934@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga14.intel.com ([192.55.52.115]:14321 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750806AbcHSFpB (ORCPT ); Fri, 19 Aug 2016 01:45:01 -0400 Content-Disposition: inline In-Reply-To: <3592cfe2-a563-7c26-9a9e-925051cc1934@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Sinan Kaya Cc: Russell King - ARM Linux , linux-arm-msm@vger.kernel.org, timur@codeaurora.org, linux-kernel@vger.kernel.org, Christopher Covington , dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org On Thu, Aug 18, 2016 at 11:48:52PM -0400, Sinan Kaya wrote: > On 8/18/2016 11:42 PM, Vinod Koul wrote: > > On Thu, Aug 18, 2016 at 11:26:28PM -0400, Sinan Kaya wrote: > >> On 8/18/2016 10:48 PM, Vinod Koul wrote: > >>>> Keep a size limited list with error cookies and flush them in terminate all? > >>> I think so, terminate_all anyway cleans up the channel. Btw what is the > >>> behaviour on error? Do you terminate or somthing else? > >>> > >> > >> On error, I flush all outstanding transactions with an error code and I reset > >> the channel. After the reset, the DMA channel is functional again. The client > >> doesn't need to shutdown anything. > > > > You mean from the client context or driver? > > > > The client doesn't need to call device_free_chan_resources and device_terminate_all > to be specific. Client can certainly call these if it needs to but it is not > required to recover the channel. You didn't answer my question! On error you said you flush, so who does that? > After the reset in error condition, the client can continue issuing new requests > with tx_submit and device_issue_pending as usual. -- ~Vinod From mboxrd@z Thu Jan 1 00:00:00 1970 From: vinod.koul@intel.com (Vinod Koul) Date: Fri, 19 Aug 2016 11:22:52 +0530 Subject: [PATCH] dmaengine: qcom_hidma: release the descriptor before the callback In-Reply-To: <3592cfe2-a563-7c26-9a9e-925051cc1934@codeaurora.org> References: <20160804144003.GV1041@n2100.armlinux.org.uk> <20160808090203.GY9681@localhost> <21475c6e-a5f8-5125-3998-f3995ce67c4d@codeaurora.org> <20160810172805.GH9681@localhost> <20160819024853.GR9681@localhost> <8c096fee-9749-a7df-7e04-25d21c0ea9ac@codeaurora.org> <20160819034249.GS9681@localhost> <3592cfe2-a563-7c26-9a9e-925051cc1934@codeaurora.org> Message-ID: <20160819055252.GT9681@localhost> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Aug 18, 2016 at 11:48:52PM -0400, Sinan Kaya wrote: > On 8/18/2016 11:42 PM, Vinod Koul wrote: > > On Thu, Aug 18, 2016 at 11:26:28PM -0400, Sinan Kaya wrote: > >> On 8/18/2016 10:48 PM, Vinod Koul wrote: > >>>> Keep a size limited list with error cookies and flush them in terminate all? > >>> I think so, terminate_all anyway cleans up the channel. Btw what is the > >>> behaviour on error? Do you terminate or somthing else? > >>> > >> > >> On error, I flush all outstanding transactions with an error code and I reset > >> the channel. After the reset, the DMA channel is functional again. The client > >> doesn't need to shutdown anything. > > > > You mean from the client context or driver? > > > > The client doesn't need to call device_free_chan_resources and device_terminate_all > to be specific. Client can certainly call these if it needs to but it is not > required to recover the channel. You didn't answer my question! On error you said you flush, so who does that? > After the reset in error condition, the client can continue issuing new requests > with tx_submit and device_issue_pending as usual. -- ~Vinod