On Fri, May 08, 2020 at 10:59:38AM -0700, Matthias Kaehlcke wrote:
> Hi Akash,
>
> overall this looks good to me, a few comments inline
>
> On Fri, May 08, 2020 at 12:03:34PM +0530, Akash Asthana wrote:
> > QUP core clock is shared among all the SE drivers present on particular
> > QUP wrapper, the system will reset(unclocked access) if earlycon used after
> > QUP core clock is put to 0 from other SE drivers before real console comes
> > up.
> >
> > As earlycon can't vote for it's QUP core need, to fix this add ICC
> > support to common/QUP wrapper driver and put vote for QUP core from
> > probe on behalf of earlycon and remove vote during earlycon exit call.
> >
> > Signed-off-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>
> > Reported-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> > ---
> > Change in V3:
> > - Add geni_remove_earlycon_icc_vote API that will be used by earlycon
> > exit function to remove ICC vote for earlyconsole.
> > - Remove suspend/resume hook for geni-se driver as we are no longer
> > removing earlyconsole ICC vote from system suspend, we are removing
> > from earlycon exit.
> >
> > Change in V4:
> > - As per Matthias comment make 'earlycon_wrapper' as static structure.
> >
> > Changes in V5:
> > - Vote for core path only after checking whether "qcom_geni" earlycon is
> > actually present or not by traversing over structure "console_drivers".
> >
> > drivers/soc/qcom/qcom-geni-se.c | 63 +++++++++++++++++++++++++++++++++++
> > drivers/tty/serial/qcom_geni_serial.c | 7 ++++
> > include/linux/qcom-geni-se.h | 2 ++
> > 3 files changed, 72 insertions(+)
> >
> > diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> > index 63403bf..66fe6f2 100644
> > --- a/drivers/soc/qcom/qcom-geni-se.c
> > +++ b/drivers/soc/qcom/qcom-geni-se.c
...
> > +#ifdef CONFIG_SERIAL_EARLYCON
> > + if (console_drivers)
>
> The loop should have curly braces ("use braces when a loop contains more than
> a single simple statement"), even though the compiler doesn't need them in
> this case. This is not a loop, but I was told by a maintainer that it equally
> applies, which makes sense.
>
> You could avoid one level of indentation through:
>
> if (!console_drivers)
> goto exit;
>
> > + for_each_console(bcon)
Actually the NULL check of 'console_drivers' is not needed:
#define for_each_console(con) \
for (con = console_drivers; con != NULL; con = con->next)
see also:
commit caa72c3bc584bc28b557bcf1a47532a7a6f37e6f
Author: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Date: Mon Feb 3 15:31:25 2020 +0200
console: Drop double check for console_drivers being non-NULL
