Re: [PATCH 1/2] ARM: imx: drop uneccessary of_platform_default_populate

[Shawn Guo]

On Mon, Mar 18, 2019 at 02:31:34AM +0000, Peng Fan wrote:
> 
> 
> > -----Original Message-----
> > From: Aisheng Dong
> > Sent: 2019å3æ15æ 21:39
> > To: Peng Fan <peng.fan@xxxxxxx>; shawnguo@xxxxxxxxxx;
> > s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; festevam@xxxxxxxxx;
> > dl-linux-imx <linux-imx@xxxxxxx>; Anson Huang <anson.huang@xxxxxxx>;
> > arnd@xxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Cc: van.freenix@xxxxxxxxx
> > Subject: RE: [PATCH 1/2] ARM: imx: drop uneccessary
> > of_platform_default_populate
> > 
> > [...]
> > 
> > > > Originally devices are registered in arch_initcall. Now it will be a
> > > > bit later in arch_initcall_sync and this may cause a bit risk if the
> > > > code under the default_populate want to access the device service
> > > > provided
> > > by early probe.
> > > >
> > > > Probably it's more safe to leave as it is unless you can double
> > > > confirm there're no such code depends on accessing early probed
> > > > devices as follows before we can make the change.
> > >
> > > This has been boot tested on 6Q-SDB/6UL-EVK/6SL-EVK board.
> > > For i.MX, I only see pinctrl driver use arch_initcall from the link,
> > > https://elixir.bootlin.com/linux/latest/ident/arch_initcall
> > >
> > > From my boot test, the pinctrl driver probe will be delayed a bit, but
> > > I do not see issues.
> > >
> > 
> > From what I saw, imx6q_1588_init() and imx6q_axi_init() will use syscon which
> > is registered with postcore_initcall. Without having syscon devices populated,
> > I wonder those calls may fall.
> > Can you double check it?
> 
> I do not see failure in imx6q_1588_init by adding a return value check of
> regmap_update_bits, But the imx6q_pm_init will find ocram device for
> suspend usage, postpone the device population will make imx6q_pm_init
> fail, so drop this patch and leave the code as it is.

Ah, okay.  Thanks for the careful review and the check, Aisheng, Peng.

Shawn