Re: [PATCH v4 3/5] soc: qcom: Introduce APCS IPC driver

From: Jassi Brar
Date: Fri May 05 2017 - 16:22:58 EST


On Sat, May 6, 2017 at 1:23 AM, Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx> wrote:
> On 5/5/2017 1:22 PM, Jassi Brar wrote:
>>
>> On Sat, May 6, 2017 at 12:07 AM, Bjorn Andersson
>> <bjorn.andersson@xxxxxxxxxx> wrote:
>>>
>
> There is no way to determine if the remote processor has observed a message,
> that does not involve pretty trivial race conditions.
>
Thanks for chiming in.
How is it supposed to work if a client queues more than one request?
How do you know when it's ok to overwrite the FIFO and send the next
command?
Usually if h/w doesn't indicate, we cook up some ack packet for each
command. Otherwise the protocol seems badly broken.

If there is really nothing that can be done to check delivery of a
message, I'll pick the driver as such. Best of luck :)