Re: [PATCH v3] mhi: pci_generic: Ensure device readiness before starting MHI

[Bhaumik Bhatt <bbhatt@codeaurora.org>]

On 2021-02-14 11:30 PM, Loic Poulain wrote:
> Hi Bhaumik,
> 
> On Fri, 12 Feb 2021 at 02:41, Bhaumik Bhatt <bbhatt@codeaurora.org> 
> wrote:
>> 
>> Hi Loic,
>> 
>> On 2021-02-11 11:25 AM, Loic Poulain wrote:
>> > The PCI device may have not been bound from cold boot and be in
>> > undefined state, or simply not yet ready for MHI operations. This
>> > change ensures that the MHI layer is reset to initial state and
>> > ready for MHI initialization and power up.
>> >
>> > Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> [...]
>> > +
>> >       err = mhi_sync_power_up(mhi_cntrl);
>> >       if (err) {
>> >               dev_err(&pdev->dev, "failed to power up MHI controller\n");
>> 
>> Can you share logs of what you're seeing as it is not clear why you
>> would need
>> this patch.
>> 
>> We have a mechanism in place that Jeff added a while back [1], to 
>> check
>> if device
>> is in SYS_ERROR state and do the same: issue reset and later, wait for
>> ready from
>> within mhi_sync_power_up() API.
>> 
>> Note that the MHI_IN_PBL() macro includes EDL and Pass Through modes 
>> as
>> well and
>> we do expect an MHI READY state move after Pass Through.
> 
> I think this is a mix of several issues, that could be fixed by latest
> Jeffrey's patch and
> this one: "mhi: core: Move to polling method to wait for MHI ready".
> 
> I assume it would be easier if you send this last one as standalone
> fix, for review and merge.
> 
Will do.
> Regards,
> Loic

Thanks,
Bhaumik
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