Re: [PATCH v3 3/8] mailbox: Add transmit done by blocking option

Mikko Perttunen
2018-08-04T10:46:08Z

On 08/03/2018 03:54 PM, Jassi Brar wrote:
> On Mon, Jul 2, 2018 at 5:10 PM, Mikko Perttunen <mperttunen@nvidia.com> wrote:
>> Add a new TXDONE option, TXDONE_BY_BLOCK. With this option, the
>> send_data function of the mailbox driver is expected to block until
>> the message has been sent. The new option is used with the Tegra
>> Combined UART driver to minimize unnecessary overhead when transmitting
>> data.
>>
> 1) TXDONE_BY_BLOCK flag :-
> Have you tried setting the flag mbox_chan->mbox_client->tx_block ?

No - I suppose I should have done that. I'm a bit concerned about
overhead as send_data may be called thousands of times per second, so I
tried to make it as close as possible to the downstream driver that just
pokes the mailbox register directly.

>
> 2) Implementing TEGRA_HSP_MBOX_TYPE_SM :-
> In mailbox framework, a controller is a collection of identical
> channels. That is, instances of the same class.
> So ideally, in probe you should populate a controller for each
> type of channel, i.e, DB, SM, SS and AS.

Hmm, yes, I guess this would be possible if I change the mailbox core to
allow registering multiple controllers per device.

Thanks!
Mikko

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