Merge pull request #433 from mcdonc/p52

add p52

README.md

@@ -124,6 +124,7 @@ See code for all available configurations.
 | [Lenovo ThinkPad P1 Gen 3](lenovo/thinkpad/p1/3th-gen)              | `<nixos-hardware/lenovo/thinkpad/p1/3th-gen>`      |
 | [Lenovo ThinkPad P14s AMD Gen 2](lenovo/thinkpad/p14s/amd/gen2)     | `<nixos-hardware/lenovo/thinkpad/p14s/amd/gen2>`   |
 | [Lenovo ThinkPad P1](thinkpad/p1)                                   | `<nixos-hardware/lenovo/thinkpad/p1>`              |
+| [Lenovo ThinkPad P52](lenovo/thinkpad/p52)                          | `<nixos-hardware/lenovo/thinkpad/p52>`             |
 | [Lenovo ThinkPad P53](lenovo/thinkpad/p53)                          | `<nixos-hardware/lenovo/thinkpad/p53>`             |
 | [Lenovo ThinkPad T14 AMD Gen 1](lenovo/thinkpad/t14/amd/gen1)       | `<nixos-hardware/lenovo/thinkpad/t14/amd/gen1>`    |
 | [Lenovo ThinkPad T14 AMD Gen 2](lenovo/thinkpad/t14/amd/gen2)       | `<nixos-hardware/lenovo/thinkpad/t14/amd/gen2>`    |

flake.nix

@@ -66,6 +66,7 @@
       lenovo-thinkpad-p1 = import ./lenovo/thinkpad/p1;
       lenovo-thinkpad-p1-gen3 = import ./lenovo/thinkpad/p1/3th-gen;
       lenovo-thinkpad-p14s-amd-gen2 = import ./lenovo/thinkpad/p14s/amd/gen2;
+      lenovo-thinkpad-p52 = import ./lenovo/thinkpad/p52;
       lenovo-thinkpad-p53 = import ./lenovo/thinkpad/p53;
       lenovo-thinkpad-t14 = import ./lenovo/thinkpad/t14;
       lenovo-thinkpad-t14-amd-gen1 = import ./lenovo/thinkpad/t14/amd/gen1;

lenovo/thinkpad/p52/default.nix

@@ -0,0 +1,76 @@
+{ lib, config, ... }: {
+  imports = [
+    ../../../common/gpu/nvidia.nix
+    ../../../common/cpu/intel
+    ../../../common/pc/laptop/acpi_call.nix
+    ../.
+  ];
+
+  hardware = {
+    nvidia = {
+      prime = {
+        intelBusId = lib.mkDefault "PCI:0:2:0";
+        nvidiaBusId = lib.mkDefault "PCI:1:0:0";
+      };
+    };
+
+    # is this too much?  It's convenient for Steam.
+    opengl = {
+      driSupport = lib.mkDefault true;
+      driSupport32Bit = lib.mkDefault true;
+    };
+  };
+
+  # required to make wireless work
+  hardware.enableAllFirmware = lib.mkDefault true;
+
+  # fix suspend/resume screen corruption in sync mode
+  hardware.nvidia.powerManagement =
+    lib.mkIf config.hardware.nvidia.prime.sync.enable {
+      enable = lib.mkDefault true;
+    };
+
+  # fix screen tearing in sync mode
+  hardware.nvidia.modesetting =
+    lib.mkIf config.hardware.nvidia.prime.sync.enable {
+      enable = lib.mkDefault true;
+    };
+
+  # Make the DPI the same in sync mode as in offload mode (disabled because
+  # these thinkpads come with many kinds of screens, but this is valid for the
+  # 1920x1080 ones)
+  #services.xserver.dpi = 96;
+
+  # silence ACPI "errors" at boot shown before NixOS stage 1 output (default is 4)
+  #boot.consoleLogLevel = 3;
+
+  # throttled vs. thermald
+  # -----------------------
+  #
+  # NB: the p53 profile currently uses throttled to prevent too-eager CPU
+  # throttling.  I understand throttled to have been a workaround solution at
+  # the time the p53 profile was created (throttled's original name was
+  # "lenovo_fix").  thermald would have been preferred if it worked at the
+  # time.
+  #
+  # I read
+  # https://wiki.archlinux.org/title/Lenovo_ThinkPad_X1_Carbon_(Gen_6)#Power_management.2FThrottling_issues
+  # as saying that thermald is fixed under the circumstance that led to the
+  # development of throttled given version 5.12+ of the kernel combined
+  # with version 2.4.3+ of thermald.  At the time of this writing, the
+  # stable NixOS kernel is 5.15 and 2.4.9 of thermald.
+  #
+  # In the meantime, I also ran the "s-tui" program which can stress test the
+  # system, while eyeing up the core temps and CPU frequency under three
+  # scenarios: under thermald, under throttled, and with neither.  None of the
+  # scenarios seem to have massively improved fan behavior, core temps, or
+  # average CPU frequency than another.  The highest core temp always seems to
+  # hover around 90 degrees C, the lowest CPU Ghz around 3.4 on a 3.8Ghz machine.
+  #
+  # I ended up choosing throttled because subjectively, the fans seem quieter
+  # when it's stressed and it allows the average temps to get a degree or two
+  # higher when running throttled than when running in the other two scenarios,
+  # but still substantially under critical temp.
+
+  services.throttled.enable = lib.mkDefault true;
+}