Re: [PATCH v6 05/12] power-domain: Add refcounting

[Tom Rini <trini@konsulko.com>]

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On Mon, Apr 14, 2025 at 01:07:27PM -0500, Nishanth Menon wrote:
> On 23:06-20250414, Francis, Neha wrote:
> > On 4/3/2025 1:09 PM, Miquel Raynal wrote:
> > > It is very surprising that such an uclass, specifically designed to
> > > handle resources that may be shared by different devices, is not keeping
> > > the count of the number of times a power domain has been
> > > enabled/disabled to avoid shutting it down unexpectedly or disabling it
> > > several times.
> > > 
> > > Doing this causes troubles on eg. i.MX8MP because disabling power
> > > domains can be done in recursive loops were the same power domain
> > > disabled up to 4 times in a row. PGCs seem to have tight FSM internal
> > > timings to respect and it is easy to produce a race condition that puts
> > > the power domains in an unstable state, leading to ADB400 errors and
> > > later crashes in Linux.
> > > 
> > > CI tests using power domains are slightly updated to make sure the count
> > > of on/off calls is even and the results match what we *now* expect.
> > > 
> > > As we do not want to break existing users while stile getting
> > > interesting error codes, the implementation is split between:
> > > - a low-level helper reporting error codes if the requested transition
> > >   could not be operated,
> > > - a higher-level helper ignoring the "non error" codes, like EALREADY and
> > >   EBUSY.
> > > 
> > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> > > ---
> > 
> > This commit looks to be breaking K3 platforms boot, please see "Latest Boot
> > Summary" [0]. Reverting the commit fixes boot.
> > 
> > [0] https://lcpd.itg.ti.com/upstream/k3-boot-build/main/build-trends.html
> 
> Uggh. This link is a TI internal link. Nutshell, it is broken
> between:
> v2025.04-921-gcb7555e93075 : https://source.denx.de/u-boot/u-boot.git
> and
> v2025.04-1041-g407d68638fe3 : https://source.denx.de/u-boot/u-boot.git
> 
> Neha bisected it down to 197376fbf300e92afa0a1583815d9c9eb52d613a commit
> which is this patch.

And assuming it's the same failure I got reported this morning by one of
my coworkers, we just get:
U-Boot SPL 2025.04-01050-ga40fc5afaec0 (Apr 14 2025 - 07:31:32 +0000)
SYSFW ABI: 3.1 (firmware rev 0x0009 '9.2.7--v09.02.07 (Kool Koala)')

For example on console.

-- 
Tom

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