Add nushell port of autoaspm

Author: Yethal

sourced/auto_aspm.nu

@@ -0,0 +1,126 @@
+#!/usr/bin/env nu
+
+const aspm = {
+    DISABLED: 0b00
+    L0s: 0b01
+    L1: 0b10
+    L0sL1: 0b11
+}
+
+def get-bytes-for-device [
+    device: string
+]: nothing -> binary {
+    sudo lspci -s $device -xxx
+    | lines
+    | skip
+    | compact -e
+    | split column -c ':'
+    | get column2
+    | split row ' '
+    | compact -e
+    | str join
+    | decode hex
+    | if ($in|bytes length) < 256 {
+        print $"Invalid byte length detected for device ($device) aborting"
+        exit
+    } else {
+        $in
+    }
+}
+
+def find-bytes [
+    bytes: binary
+    pos: int
+]: nothing -> int {
+    # absolute black magic
+    let result = ($bytes|bytes at $pos..$pos|into int)
+    if $result != 0x10 {
+        find-bytes $bytes ($result + 0x1)
+    } else {
+        return ($result + 0x10)
+    }
+}
+
+def patch-device [
+    device: string
+    aspm_value: string
+] {
+    let bytes = (get-bytes-for-device $device)
+    let byte_position = (find-bytes $bytes 0x34) #no one really knows where this value comes from
+    let byte_to_patch = (
+        $bytes
+        | bytes at $byte_position..$byte_position
+        | into int
+    )
+    # no idea
+    if ($byte_to_patch| bits and 0b11) == ($aspm|get $aspm_value) {
+        print $"($device) already has ASPM ($aspm_value) enabled"
+    } else {
+        print $"Enabling ASPM ($aspm_value) for device ($device)"
+        let new_byte_value = (
+            $byte_to_patch
+            | bits shr 2 #no idea why we bitshift right and left
+            | bits shl 2
+            | bits or ($aspm|get $aspm_value)
+        )
+        patch-byte $device $byte_position $new_byte_value
+        print $"Enabled ASPM ($aspm_value) for device ($device)"
+    }
+}
+
+def patch-byte [
+    device: string
+    position: int
+    value: int
+] {
+    setpci -s $device $"($position|format number|get upperhex).B=($value|format number|get upperhex)"
+}
+
+def get-supported-devices []: nothing -> table<address: string, supported_aspm: string> {
+    lspci -vv
+    | lines
+    | split list ''
+    | each {|device|
+
+        let address = (
+            $device
+            | first
+            | split row ' '
+            | first
+        )
+
+        let params = ($device|skip)
+
+        if ($params|find "ASPM"|is-empty) or ($params|find "ASPM not supported"|is-not-empty) {
+            null
+        } else {
+            let supported_aspm = (
+                $params
+                | parse -r "ASPM (L[L0-1s ]*),"
+                | get capture0.0
+                | str replace " " ""
+            )
+            {address: $address, supported_aspm: $supported_aspm}
+        }
+    }
+}
+
+if not (is-admin) {
+    error make -u {
+        msg: "This script needs to be run as root"
+    }
+}
+if $nu.os-info.name != "linux" {
+    error make -u {
+        msg: "This script needs to run under Linux"
+    }
+}
+if (which lspci setpci|length) < 2 {
+    error make -u {
+        msg: "lspci and setpci need to be available in PATH"
+    }
+}
+
+for device in (get-supported-devices) {
+    patch-device $device.address $device.supported_aspm
+}