Re: [PATCH v2 03/18] firmware: arm_scmi: add basic driver infrastructure for SCMI

[Jassi Brar]

On Tue, Aug 8, 2017 at 2:59 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
>
>
> On 08/08/17 03:46, Jassi Brar wrote:
>> On Fri, Aug 4, 2017 at 8:01 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
>>
>> ....
>>> +int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer)
>>> +{
>>> +       int ret;
>>> +       int timeout;
>>> +       struct scmi_info *info = handle_to_scmi_info(handle);
>>> +       struct device *dev = info->dev;
>>> +
>>> +       ret = mbox_send_message(info->tx_chan, xfer);
>>>
>> NAK
>>
>> This is still not fixed. For the reasons mentioned many times like
>> here...   https://lkml.org/lkml/2017/7/7/465
>>
>
> Since SCPI and SCMI are based on doorbell designs like ACPI PCC, they
> can't send any data as all the data are part of shared memory.
>
> What data needs to be sent from SCPI/SCMI as part of mbox_send_message
> in your opinion ? I can't think of any generic way to form this data.
>
https://lkml.org/lkml/2017/7/7/290