| Message ID | 20250423075143.11157-2-johan+linaro@kernel.org |
|---|---|
| State | Accepted |
| Headers | show |
| Series | rtc: pm8xxx: fix uefi offset lookup | expand |
On Wed, 23 Apr 2025 09:51:40 +0200, 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 a > driver can take into account. > > On platforms where the offset is stored in a Qualcomm specific UEFI > variable the variables are also accessed in a non-standard way, which > means that the OS cannot assume that the variable service is available > by the time the RTC driver probes. > > Add a 'qcom,uefi-rtc-info' boolean flag to indicate that the RTC offset > is stored in a Qualcomm specific UEFI variable so that the OS can > determine whether to wait for it to become available. > > The UEFI variable is > > 882f8c2b-9646-435f-8de5-f208ff80c1bd-RTCInfo > > and holds a 12-byte structure where the first four bytes is a GPS time > offset in little-endian byte order. > > Link: https://lore.kernel.org/all/aAecIkgmTTlThKEZ@hovoldconsulting.com/ > Signed-off-by: Johan Hovold <johan+linaro@kernel.org> > --- > Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml | 6 ++++++ > 1 file changed, 6 insertions(+) > Acked-by: Rob Herring (Arm) <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml b/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml index 68ef3208c886..7497dc3ac5b2 100644 --- a/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml +++ b/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml @@ -55,6 +55,12 @@ properties: description: RTC alarm is not owned by the OS + qcom,uefi-rtc-info: + type: boolean + description: + RTC offset is stored as a four-byte GPS time offset in a 12-byte UEFI + variable 882f8c2b-9646-435f-8de5-f208ff80c1bd-RTCInfo + wakeup-source: true required:
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. On platforms where the offset is stored in a Qualcomm specific UEFI variable the variables are also accessed in a non-standard way, which means that the OS cannot assume that the variable service is available by the time the RTC driver probes. Add a 'qcom,uefi-rtc-info' boolean flag to indicate that the RTC offset is stored in a Qualcomm specific UEFI variable so that the OS can determine whether to wait for it to become available. The UEFI variable is 882f8c2b-9646-435f-8de5-f208ff80c1bd-RTCInfo and holds a 12-byte structure where the first four bytes is a GPS time offset in little-endian byte order. Link: https://lore.kernel.org/all/aAecIkgmTTlThKEZ@hovoldconsulting.com/ Signed-off-by: Johan Hovold <johan+linaro@kernel.org> --- Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml | 6 ++++++ 1 file changed, 6 insertions(+)