Re: [PATCH 3/7] rtc: pm8xxx: add support for uefi offset
From: Johan Hovold
Date: Mon Jan 20 2025 - 10:17:42 EST
On Mon, Jan 20, 2025 at 04:15:54PM +0100, Johan Hovold wrote:
> On Mon, Jan 20, 2025 at 03:10:24PM +0000, Sudeep Holla wrote:
> > On Mon, Jan 20, 2025 at 03:41:48PM +0100, Johan Hovold wrote:
> > > On many Qualcomm platforms the PMIC RTC control and time registers are
> > > read-only so that the RTC time can not be updated. Instead an offset
> > > needs be stored in some machine-specific non-volatile memory, which the
> > > driver can take into account.
> > >
> > > Add support for storing a 32-bit offset from the GPS time epoch in a
> > > UEFI variable so that the RTC time can be set on such platforms.
> > >
> >
> > Why can't the UEFI runtime services be used here ?
> > In short, why is drivers/rtc/rtc-efi.c not working or no attempts are
> > made to check if that works just fine ?
>
> As I alluded to in the commit message, the Qualcomm UEFI implementation
s/commit message/cover letter/
> is broken and the runtime services cannot be accessed during runtime...
>
> That's why we can't use rtc-efi and why we have a dedicated efivars
> implementation that talks directly to the firmware using a custom
> protocol:
>
> https://lore.kernel.org/all/20220723224949.1089973-1-luzmaximilian@xxxxxxxxx/
Johan