lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Message-Id: <20250122-jg-blackrock-rtc-v1-1-3b05cd85bdfa@oldschoolsolutions.biz>
Date: Wed, 22 Jan 2025 07:41:56 +0100
From: Jens Glathe via B4 Relay <devnull+jens.glathe.oldschoolsolutions.biz@...nel.org>
To: Bjorn Andersson <andersson@...nel.org>, 
 Konrad Dybcio <konradybcio@...nel.org>, Rob Herring <robh@...nel.org>, 
 Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>
Cc: linux-arm-msm@...r.kernel.org, devicetree@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Johan Hovold <johan@...nel.org>, 
 Jens Glathe <jens.glathe@...schoolsolutions.biz>
Subject: [PATCH] arm64: dts: qcom: sc8280xp-blackrock: switch to uefi rtc
 offset

From: Jens Glathe <jens.glathe@...schoolsolutions.biz>

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 a
driver can take into account.

Switch to using the Qualcomm specific UEFI variable that is used by the
UEFI firmware (and Windows) to store the RTC offset.

This specifically means that the RTC time will be synchronised between
the UEFI firmware setup (or UEFI shell), Windows and Linux.

Note however that Windows stores the RTC time in local time by default,
while Linux typically uses UTC (i.e. as on X86).

Based on a patch by Johan Hovold. [1]

Link: https://lore.kernel.org/all/20250120144152.11949-7-johan+linaro@kernel.org/ # [1]
Signed-off-by: Jens Glathe <jens.glathe@...schoolsolutions.biz>
---
This is a patch to switch the Windows Dev Kit 2023 over to
using the UEFI offset.
---
 arch/arm64/boot/dts/qcom/sc8280xp-microsoft-blackrock.dts | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-blackrock.dts b/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-blackrock.dts
index fa9d941050522..aaea2fa3c6c0a 100644
--- a/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-blackrock.dts
+++ b/arch/arm64/boot/dts/qcom/sc8280xp-microsoft-blackrock.dts
@@ -762,20 +762,11 @@ &pmk8280_pon_resin {
 };
 
 &pmk8280_rtc {
-	nvmem-cells = <&rtc_offset>;
-	nvmem-cell-names = "offset";
+	qcom,uefi-rtc-info;
 
 	status = "okay";
 };
 
-&pmk8280_sdam_6 {
-	status = "okay";
-
-	rtc_offset: rtc-offset@bc {
-		reg = <0xbc 0x4>;
-	};
-};
-
 &pmk8280_vadc {
 	channel@144 {
 		reg = <PM8350_ADC7_AMUX_THM1_100K_PU(1)>;

---
base-commit: 232f121837ad8b1c21cc80f2c8842a4090c5a2a0
change-id: 20250120-jg-blackrock-rtc-b4917e6bce94

Best regards,
-- 
Jens Glathe <jens.glathe@...schoolsolutions.biz>



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ