diff --git a/src/content/docs/configuration/boot_manager_configuration.mdx b/src/content/docs/configuration/boot_manager_configuration.mdx index 92c8e4454..221c85a01 100644 --- a/src/content/docs/configuration/boot_manager_configuration.mdx +++ b/src/content/docs/configuration/boot_manager_configuration.mdx @@ -221,6 +221,78 @@ While entries are handled automatically, you can **configure the kernel paramete This command triggers the `mkinitcpio` process, which includes the `limine-mkinitcpio-hook`, ensuring your changes in `/etc/default/limine` are incorporated into the boot entries at `/boot/limine.conf`. +## Workaround: Slow Charging on HP OmniBook X Flip + +Some HP OmniBook laptops (e.g., the OmniBook X Flip 16-ar0xxx) charge at a crawl under Linux — roughly 0.2 W instead of the expected 30 W+. The embedded controller (EC) firmware only enables fast charging when the ACPI `_OSI("Windows 2022")` query is answered, and falls back to a degraded mode otherwise. + +CachyOS kernels do not provide the `acpi_rev_override` option, so the workaround is to answer the `_OSI` query directly on the kernel command line: + +```shell +acpi_osi=! acpi_osi="Windows 2022" +``` + +The first part (`acpi_osi=!`) clears the OSI strings, the second re-answers the `Windows 2022` query. Note that `acpi_osi=!` removes **all** Windows OSI responses, which may affect other Windows-specific workarounds. + +### Limine + +Append the parameters in `/etc/default/limine` — the `+=` appends to the distribution defaults instead of replacing them: + +```shell +# /etc/default/limine + +KERNEL_CMDLINE[default]+=acpi_osi=! acpi_osi="Windows 2022" +``` + +Then regenerate the entries: + +```bash +sudo limine-mkinitcpio +``` + +### GRUB + +Add the parameters to `GRUB_CMDLINE_LINUX_DEFAULT` in `/etc/default/grub` and regenerate the configuration: + +```shell +# /etc/default/grub + +GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=! acpi_osi=\"Windows 2022\"" +``` + +```bash +sudo grub-mkconfig -o /boot/grub/grub.cfg +``` + +### systemd-boot + +Add the parameters to the `LINUX_OPTIONS` line in `/etc/sdboot-manage.conf` and regenerate the entries: + +```shell +# /etc/sdboot-manage.conf + +LINUX_OPTIONS="zswap.enabled=0 nowatchdog quiet splash acpi_osi=! acpi_osi=\"Windows 2022\"" +``` + +```bash +sudo sdboot-manage gen +``` + +### Verifying + +After a reboot, confirm the parameters are active and check the charging rate: + +```shell +cat /proc/cmdline +cat /sys/class/power_supply/BAT0/power_now +``` + +With the workaround, `power_now` reports tens of millions of microwatts (i.e., 30 W+) while charging; without it, it stays around 200000 (0.2 W). + +### References + +* [Kernel Bugzilla 221866: Slow charging on HP OmniBook X Flip with Linux](https://bugzilla.kernel.org/show_bug.cgi?id=221866) +* [CachyOS issue #971: HP OmniBook X Flip slow charging under Linux](https://github.com/CachyOS/linux-cachyos/issues/971) + ## Learn more * [loader.conf manual page](https://man.archlinux.org/man/loader.conf.5)