Dell XPS 13 2-in-1 (9365)

BIOS configuration

Bios can be accessed with F2 or F12 on DELL logo boot screen.

With Bios version 1.1.0 or 1.3.1 to 2.1.2 you have to set sata operation to AHCI first and then uncheck in Advanced Boot options -> Legacy ROM.

It is also needed to set the following settings  :

• UEFI network stack - disabled
• Secure Boot - disabled
• SATA operations - AHCI
• Legacy ROM - disabled
• POST Behaviour : Fastboot - minimal (if not, BIOS is really slow, and cannot boot to any mediums)

Secure Boot

The UEFI supports custom keys.

Firmware data path

The BIOS stores logs in esp/EFI/Dell.

diags_previous.xml

<?xml version="1.0" encoding="UTF-8"?>
  <SupportAssistPrebootDiagnosticLog>
    <Schema>1.0.0</Schema>
    <LogNumber>47</LogNumber>
    <LogTimeStamp>03/07/2024 18:18:49</LogTimeStamp>
    <ePSA_Data>
      <Result>Not Reported</Result>
      <ReturnCode>BOOT_HOST_OS</ReturnCode>
      <ePSAFullVersion>2.27</ePSAFullVersion>
      <ePSAInvocationCount>1</ePSAInvocationCount>
    </ePSA_Data>
    <BIOS_Data>
      <ErrorCategory>BATTERY</ErrorCategory>
      <ErrorMessage><![CDATA[WARNING: Battery is critically low.
]]></ErrorMessage>
      <FRU_String><![CDATA[Unknown Battery]]></FRU_String>
      <SOS_Available>FALSE</SOS_Available>
      <TimeOutSeconds>0</TimeOutSeconds>
    </BIOS_Data>
  </SupportAssistPrebootDiagnosticLog>

diags_current.xml

<?xml version="1.0" encoding="UTF-8"?>
  <SupportAssistPrebootDiagnosticLog>
    <Schema>1.0.0</Schema>
    <LogNumber>48</LogNumber>
    <LogTimeStamp>01/01/2012 00:00:44</LogTimeStamp>
    <ePSA_Data>
      <Result>Not Reported</Result>
      <ReturnCode>BOOT_HOST_OS</ReturnCode>
      <ePSAFullVersion>2.27</ePSAFullVersion>
      <ePSAInvocationCount>1</ePSAInvocationCount>
    </ePSA_Data>
    <BIOS_Data>
      <ErrorCategory>DISPLAY_ONLY</ErrorCategory>
      <ErrorMessage><![CDATA[Time-of-day not set - please run SETUP program.
]]></ErrorMessage>
      <SOS_Available>FALSE</SOS_Available>
      <TimeOutSeconds>0</TimeOutSeconds>
    </BIOS_Data>
  </SupportAssistPrebootDiagnosticLog>

Suspend issues

This model only supports the S0ix sleep mode, see Power management/Suspend and hibernate#Changing suspend method.

Screen not rotating

You need to install iio-sensor-proxy for automatic screen rotation to work.

Reduce throttling

On battery the device runs noticeably slower. This goes even as far as that scrolling a web browser can get stuttery while perfectly fluid when connected to a charger. It might be an issue with the performance preference of the CPU. If

$ cat /sys/devices/system/cpu/cpufreq/policy?/energy_performance_preference

reports default or balance_power it can cause the CPU to be limited in its maximum clockspeed and performance. This is expected from 'balance_power'. 'default' means the manufacturer's own settings are active but those seem to limit performance on battery quite a lot. You can change it to 'balance_performance' or 'performance' to get a higher performance at a increased power consumption. When you try the different options and use a stress test you can observe that on 'default', 'balance_power' and 'power' the maximum CPU frequency is limited. 'balance performance' should still allow for maximum frequency while still allowing some power saving. You can change it permanently with

/etc/tmpfiles.d/energy_performance_preference.conf

w /sys/devices/system/cpu/cpufreq/policy?/energy_performance_preference - - - - balance_performance

A way to save some power is to increase the energy performance bias.

/etc/tmpfiles.d/energy_performance_bias.conf

w /sys/devices/system/cpu/cpu?/power/energy_perf_bias - - - - 15

It controls how aggressive power saving mechanisms work without decreasing performance too much.