[PATCH v2] pmdomain: imx: gpcv2: Fix the imx8mm gpu hang due to wrong adb400 reset

[Jacky Bai]

> Subject: Re: [PATCH v2] pmdomain: imx: gpcv2: Fix the imx8mm gpu hang due
> to wrong adb400 reset
> 
> On Thu, Jan 22, 2026 at 7:54 AM Jacky Bai <ping.bai at nxp.com> wrote:
> >
> > On i.MX8MM, the GPUMIX, GPU2D, and GPU3D blocks share a common
> reset
> > domain. Due to this hardware limitation, powering off/on GPU2D or
> > GPU3D also triggers a reset of the GPUMIX domain, including its ADB400
> port.
> > However, The ADB400 interface must always be placed into power‑down
> > before being reset.
> >
> > Currently the GPUMIX and GPU2D/3D power domains rely on runtime PM
> to
> > handle dependency ordering. In some corner cases, the GPUMIX power‑off
> > sequence is skipped, leaving the ADB400 port active when GPU2D/3D
> resets.
> > This causes the GPUMIX ADB400 port to be reset while still active,
> > leading to unpredictable bus behavior and GPU hangs.
> >
> > To avoid this, refine the power‑domain control logic so that the
> > GPUMIX
> > ADB400 port is explicitly powered down and powered up as part of the
> > GPU power‑domain on/off sequence. This ensures proper ordering and
> > prevents incorrect ADB400 resets.
> >
> > Suggested by: Lucas Stach <l.stach at pengutronix.de>
> 
> Correct tag here is:
> 
> Suggested-by: Lucas Stach <l.stach at pengutronix.de>
> 
> Also, no need for a new line between tags.

Don’t know why it changed after sent out. Let me check and resend it.

BR
Jacky Bai
> >
> > Signed-off-by: Jacky Bai <ping.bai at nxp.com>