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

[Loic Poulain <loic.poulain@linaro.org>]

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.

Regards,
Loic