Created attachment 293287 [details] Output of `acpidump` Looking at the boottime of the Dell XPS 13 9310 with Ubuntu 20.04 (and 20.10) the Linux kernel takes *four* seconds until it loads the init program (systemd). 260 ms seem to be spent to figure out that the power resource PIN, whatever that is, is off. ``` [ 0.000000] Linux version 5.10.0-rc1+ (helmut@helmut-XPS-13-9310) (gcc (Ubuntu 10.2.0-13ubuntu1) 10.2.0, GNU ld (GNU Binutils for Ubuntu) 2.35.1) #2 SMP Tue Oct 27 14:58:21 CET 2020 […] [ 0.257267] ACPI: Enabled 8 GPEs in block 00 to 7F [ 0.263619] ACPI: Power Resource [BTPR] (on) [ 0.278865] ACPI: Power Resource [V0PR] (on) [ 0.279049] ACPI: Power Resource [V1PR] (on) [ 0.279230] ACPI: Power Resource [V2PR] (on) [ 0.285237] ACPI: Power Resource [WRST] (on) [ 0.298118] ACPI: Power Resource [TBT0] (on) [ 0.298169] ACPI: Power Resource [TBT1] (on) [ 0.298217] ACPI: Power Resource [D3C] (on) [ 0.558918] ACPI: Power Resource [PIN] (off) [ 0.559413] ACPI: PCI Root Bridge [PC00] (domain 0000 [bus 00-fe]) [ 0.559419] acpi PNP0A08:00: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI HPX-Type3] […] ```
Created attachment 293289 [details] Linux 5.10+ messages with `initcall_debug` (output of `dmesg`)
It could be related to not having `PINCTRL_TIGERLAKE` selected in Debian’s Linux kernel configuration [1], but I couldn’t test it yet. [1]: https://bugs.debian.org/973372
(In reply to Paul Menzel from comment #2) > It could be related to not having `PINCTRL_TIGERLAKE` selected in Debian’s > Linux kernel configuration [1], but I couldn’t test it yet. > > [1]: https://bugs.debian.org/973372 Sorry, commented on wrong bug.
Same here, with 5.11: [ 0.260314] ACPI: Power Resource [D3C] (on) [ 0.501555] ACPI: Power Resource [PIN] (off) The BIOS version of my XPS is v2.0.0.
This is still happening with Linux 5.17.3: [ 0.000000] Linux version 5.17.0-1-amd64 (debian-kernel@lists.debian.org) (gcc-11 (Debian 11.2.0-20) 11.2.0, GNU ld (GNU Binutils for Debian) 2.38) #1 SMP PREEMPT Debian 5.17.3-1 (2022-04-18) […] [ 0.000000] DMI: Dell Inc. XPS 13 9310/0GG9PT, BIOS 2.2.0 04/06/2021 […] [ 0.166572] ACPI: PM: Power Resource [D3C] [ 0.407884] ACPI: PM: Power Resource [PIN] [ 0.408109] ACPI: PCI Root Bridge [PC00] (domain 0000 [bus 00-fe]) […] on/off is not there anymore in newer Linux versions it seems.
If somebody has time, and wants to debug this, you could use ftrace to trace the method `acpi_init()`. In Linux’s source tree run sudo tools/power/pm-graph/bootgraph.py -f -manual # actually import from [1] and copy that command line to the Linux kernel command line. It’s a good start, but the two parameters 1. ftrace_graph_filter=do_one_initcall 2. ftrace_graph_max_depth=2 can be adapted. I think `do_one_initcall` could be replaced by `acpi_init` as a first step. You can easier let `bootgraph.py` analyze the data, or do it manually. $ echo 0 | sudo tee /sys/kernel/debug/tracing/tracing_on $ sudo less /sys/kernel/debug/tracing/trace Then look at the timestamps annotated with @ for the ones taking very long. [1]: https://github.com/intel/pm-graph