On 8/22/2016 2:08 AM, Vinod Koul wrote: > On Fri, Aug 19, 2016 at 01:21:34PM -0400, Sinan Kaya wrote: >> On 8/19/2016 1:02 PM, Vinod Koul wrote: >>> On Fri, Aug 19, 2016 at 07:13:43AM -0400, okaya@xxxxxxxxxxxxxx wrote: >>>> On 2016-08-19 01:52, Vinod Koul wrote: >>>>> 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? >>>> >>>> This is done by the driver in interrupt context when an error >>>> interrupt is received. All transactions are posted and hw is reset. >>> >>> Hmmm, waht about the txn which are pending? DO you clear them..? >>> >> >> Yes, I clear both pending and active transactions. > > Okay, in that case your can consider below: > > 1. dmaengine asserts error interrupt > 2. Driver receives and mark's the txn as error > 3. Driver completes the txn and intimates the client. No further > submissions. Drop the locks before calling callback, as subsequent > processing by client maybe in callback thread. > 4. Client invokes status and you can return error > 5. On error, client calls terminate_all. You can reset channel, free all > descriptors in the active, pending and completed lists > 6. Client prepares new txn and so on.. Just to be clear, you are telling me not to accept any new transactions until terminate_all is called, right? > > Thanks > -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
