RE: [PATCH V3 1/5] thermal: qoriq: Add clock operations

[Anson Huang]

Hi, Rui

> > On Wed, 2019-08-28 at 08:51 +0000, Anson Huang wrote:
> > > Hi, Rui
> > >
> > > > On Tue, 2019-08-27 at 12:41 +0000, Leonard Crestez wrote:
> > > > > On 27.08.2019 04:51, Anson Huang wrote:
> > > > > > > In an earlier series the CLK_IS_CRITICAL flags was removed
> > > > > > > from the TMU clock so if the thermal driver doesn't
> > > > > > > explicitly enable it the system will hang on probe. This is
> > > > > > > what happens in linux-next right now!
> > > > > >
> > > > > > The thermal driver should be built with module, so default
> > > > > > kernel should can boot up, do you modify the thermal driver as
> > > > > > built- in?
> > > > > >
> > > > > > > Unless this patches is merged soon we'll end up with a 5.4-
> > > > > > > rc1
> > > > > > > that doesn't boot on imx8mq. An easy fix would be to
> > > > > > > drop/revert commit
> > > > > > > 951c1aef9691 ("clk: imx8mq: Remove CLK_IS_CRITICAL flag for
> > > > > > > IMX8MQ_CLK_TMU_ROOT") until the thermal patches are
> accepted.
> > > > > >
> > > > > > If the thermal driver is built as module, I think no need to
> > > > > > revert the commit, but if by default thermal driver is
> > > > > > built-in or mod probed, then yes, it should NOT break kernel boot
> up.
> > > > >
> > > > > The qoriq_thermal driver is built as a module in defconfig and
> > > > > when modules are properly installed in rootfs they will be
> > > > > automatically be probed on boot and cause a hang.
> > > > >
> > > > > I usually run nfsroot with modules:
> > > > >
> > > > >      make modules_install INSTALL_MOD_PATH=/srv/nfs/imx8-root
> > > >
> > > > so we need this patch shipped in the beginning of the merge
> > > > window, right?
> > > > if there is hard dependency between patches, it's better to send
> > > > them in one series, and get shipped via either tree.
> > >
> > > There is no hard dependency in this patch series. Previous for the
> > > TMU clock disabled patch, since thermal driver is built as module so
> > > I did NOT found the issue. The patch series is the correct fix.
> > >
> > Got it.
> > the clock patch is also queued for 5.4-rc1, right?
> > I will apply this series and try to push it as early as possible
> > during the merge window.
> 
> The clock patch is as below in Linux-next tree, while I did NOT see it in v5.3-
> rc6, so it should be queued for 5.4-rc1, right?
> Thanks for taking the patch series!

Sorry for pushing, so you will apply this patch series to avoid the i.MX8MQ kernel boot up hang
caused by insmod qoriq thermal driver, right? Then we no need to revert that TMU clock patch
951c1aef9691 ("clk: imx8mq: Remove CLK_IS_CRITICAL flag for IMX8MQ_CLK_TMU_ROOT").

Thanks,
Anson

> 
> 
> commit 951c1aef9691491ddf4dd5aab76f2665d56bd5d3
> Author: Anson Huang <Anson.Huang@xxxxxxx>
> Date:   Fri Jul 5 12:56:11 2019 +0800
> 
>     clk: imx8mq: Remove CLK_IS_CRITICAL flag for IMX8MQ_CLK_TMU_ROOT
> 
>     IMX8MQ_CLK_TMU_ROOT is ONLY used for thermal module, the driver
>     should manage this clock, so no need to have CLK_IS_CRITICAL flag
>     set.
> 
>     Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
>     Reviewed-by: Abel Vesa <abel.vesa@xxxxxxx>
>     Acked-by: Stephen Boyd <sboyd@xxxxxxxxxx>
>     Signed-off-by: Shawn Guo <shawnguo@xxxxxxxxxx>
> 
> drivers/clk/imx/clk-imx8mq.c
> 
> 
> Thanks,
> Anson