Re: [PATCH 4.19 055/247] soc: aspeed: snoop: Add clock control logic

From: Greg Kroah-Hartman
Date: Thu Mar 04 2021 - 03:14:21 EST


On Tue, Mar 02, 2021 at 12:09:21AM +0000, Yoo, Jae Hyun wrote:
> > -----Original Message-----
> > From: Joel Stanley <joel@xxxxxxxxx>
> > Sent: Monday, March 1, 2021 2:44 PM
> > To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; John Wang
> > <wangzhiqiang.bj@xxxxxxxxxxxxx>; Yoo, Jae Hyun
> > <jae.hyun.yoo@xxxxxxxxx>
> > Cc: Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>;
> > stable@xxxxxxxxxxxxxxx; Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>;
> > Sasha Levin <sashal@xxxxxxxxxx>
> > Subject: Re: [PATCH 4.19 055/247] soc: aspeed: snoop: Add clock control logic
> >
> > On Mon, 1 Mar 2021 at 16:37, Greg Kroah-Hartman
> > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > From: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxx>
> > >
> > > [ Upstream commit 3f94cf15583be554df7aaa651b8ff8e1b68fbe51 ]
> > >
> > > If LPC SNOOP driver is registered ahead of lpc-ctrl module, LPC SNOOP
> > > block will be enabled without heart beating of LCLK until lpc-ctrl
> > > enables the LCLK. This issue causes improper handling on host
> > > interrupts when the host sends interrupt in that time frame.
> > > Then kernel eventually forcibly disables the interrupt with dumping
> > > stack and printing a 'nobody cared this irq' message out.
> > >
> > > To prevent this issue, all LPC sub-nodes should enable LCLK
> > > individually so this patch adds clock control logic into the LPC SNOOP
> > > driver.
> >
> > Jae, John; with this backported do we need to also provide a corresponding
> > device tree change for the stable tree, otherwise this driver will no longer
> > probe?
>
> Right. The second patch
> https://lore.kernel.org/linux-arm-kernel/20201208091748.1920-2-wangzhiqiang.bj@xxxxxxxxxxxxx/
> John submitted should be applied to stable tree too to make this module be probed
> correctly.

Now queued up, thanks.

greg k-h