All of lore.kernel.org
 help / color / mirror / Atom feed
From: Johan Hovold <johan@kernel.org>
To: Sudeep Holla <sudeep.holla@arm.com>
Cc: Johan Hovold <johan+linaro@kernel.org>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	Bjorn Andersson <andersson@kernel.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Konrad Dybcio <konradybcio@kernel.org>,
	Jonathan Marek <jonathan@marek.ca>,
	linux-arm-msm@vger.kernel.org, linux-rtc@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/7] rtc: pm8xxx: add support for uefi offset
Date: Mon, 20 Jan 2025 16:17:36 +0100	[thread overview]
Message-ID: <Z45pEEofHiQRkR0D@hovoldconsulting.com> (raw)
In-Reply-To: <Z45oqqnlMSNEYyil@hovoldconsulting.com>

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@gmail.com/

Johan

  reply	other threads:[~2025-01-20 15:17 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-01-20 14:41 [PATCH 0/7] arm64: dts: qcom: x1e80100: enable rtc Johan Hovold
2025-01-20 14:41 ` [PATCH 1/7] dt-bindings: rtc: qcom-pm8xxx: add uefi-variable offset Johan Hovold
2025-01-20 14:41 ` [PATCH 2/7] dt-bindings: rtc: qcom-pm8xxx: document qcom,no-alarm flag Johan Hovold
2025-01-27 18:00   ` Rob Herring (Arm)
2025-01-20 14:41 ` [PATCH 3/7] rtc: pm8xxx: add support for uefi offset Johan Hovold
2025-01-20 15:10   ` Sudeep Holla
2025-01-20 15:15     ` Johan Hovold
2025-01-20 15:17       ` Johan Hovold [this message]
2025-01-20 17:13         ` Sudeep Holla
2025-01-24 12:56   ` Tobias Heider
2025-01-24 14:07     ` Johan Hovold
2025-01-20 14:41 ` [PATCH 4/7] rtc: pm8xxx: mitigate flash wear Johan Hovold
2025-01-23 11:39   ` Johan Hovold
2025-01-20 14:41 ` [PATCH 5/7] rtc: pm8xxx: implement qcom,no-alarm flag for non-HLOS owned alarm Johan Hovold
2025-01-20 14:41 ` [PATCH 6/7] arm64: dts: qcom: sc8280xp-x13s: switch to uefi rtc offset Johan Hovold
2025-01-20 18:08   ` Jens Glathe
2025-01-23 12:26   ` Konrad Dybcio
2025-01-20 14:41 ` [PATCH 7/7] arm64: dts: qcom: x1e80100: enable rtc Johan Hovold
2025-01-20 18:12   ` Jens Glathe
2025-01-21 10:06     ` Johan Hovold
2025-01-23 12:26   ` Konrad Dybcio
2025-01-20 21:19 ` [PATCH 0/7] " Steev Klimaszewski
2025-01-21 10:06   ` Johan Hovold
2025-01-21  3:48 ` Joel Stanley
2025-01-21 10:07   ` Johan Hovold
2025-01-23 12:28 ` Konrad Dybcio
2025-01-25 18:46 ` Sebastian Reichel
2025-01-27  0:20 ` Rob Herring
2025-02-19 13:37   ` Johan Hovold
2025-04-21 14:36   ` Rob Clark
2025-04-22 13:39     ` Johan Hovold

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Z45pEEofHiQRkR0D@hovoldconsulting.com \
    --to=johan@kernel.org \
    --cc=alexandre.belloni@bootlin.com \
    --cc=andersson@kernel.org \
    --cc=conor+dt@kernel.org \
    --cc=devicetree@vger.kernel.org \
    --cc=johan+linaro@kernel.org \
    --cc=jonathan@marek.ca \
    --cc=konradybcio@kernel.org \
    --cc=krzk+dt@kernel.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rtc@vger.kernel.org \
    --cc=robh@kernel.org \
    --cc=sudeep.holla@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.