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The flip: ACPI enumeration leaves the kernel (M20.3)

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The kernel no longer folds AML Device objects into the device tree — the
ring-3 acpi service is the sole builder of _HID device nodes. The kernel
keeps building the namespace only for the \_S5 sleep type, and still
seeds the static tables (MADT, HPET, MCFG, FADT) and the acpi-tables node.

The device manager matches ps2-bus from the service's _HID reports
(PNP0303 / PNP0F13, singleton-deduped) instead of boot-snapshot nodes;
its dead boot-snapshot ps2 arm is gone. The service registers every
device before reporting any, so a driver the manager spawns on the first
report already sees the full set — no keyboard-before-mouse race. The
acpi-ps2 scenario proves the whole chain: report -> spawn -> ps2-bus
finds the controller and attaches its keyboard, entirely in ring 3. The
ioport test moved to the acpi-tables I/O window, since the kernel-built
PS/2 node it used to scan for no longer exists. The retired
device-building functions in acpi.zig are dead but retained (a botched
mechanical deletion is worse mid-migration than a follow-up sweep, which
is flagged as a task). Suite 58/58.
This commit is contained in:
Daniel Samson
2026-07-13 03:32:15 +01:00
parent 5ca804d827
commit e6d0bb7ef0
6 changed files with 101 additions and 46 deletions
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system/services/acpi/acpi.zig
+38 -23
View File
@@ -28,6 +28,11 @@ fn writeLine(comptime fmt: []const u8, arguments: anytype) void {
var node_id: u64 = 0;
var io_resource_index: u64 = 0;
// Pass-1 registration record (see main): what pass 2 reports.
const Registered = struct { hid: [8]u8 = .{0} ** 8, hid_len: usize = 0, device_id: u64 = 0, resource_count: u64 = 0 };
var registered: [64]Registered = undefined;
var registered_count: usize = 0;
// A scratch page returned for SystemMemory OperationRegion maps: the service
// cannot map arbitrary physical memory from ring 3, so such regions are
// unsupported and degrade to harmless zeros rather than faulting. The M20.2
@@ -123,10 +128,31 @@ pub fn main(init: runtime.process.Init) void {
.pioWrite = halPioWrite,
}, arena.allocator());
// Pass 1: register every present _HID device under acpi-tables, remembering
// each (hid, device id). Pass 2: report them all. Registering before any
// report reaches the manager means a driver it spawns on the first report
// already sees the whole set (no keyboard-before-mouse race for ps2-bus).
registered_count = 0;
walkDevices(namespace.root, &interpreter);
const manager = runtime.ipc.lookup(.device_manager);
var reported: u32 = 0;
walkDevices(namespace.root, &interpreter, manager, &reported);
writeLine("acpi: reported {d} device(s) to the manager\n", .{reported});
var i: usize = 0;
while (i < registered_count) : (i += 1) {
const entry = registered[i];
writeLine("acpi: reported {s} (device {d}, {d} resources)\n", .{ entry.hid[0..entry.hid_len], entry.device_id, entry.resource_count });
if (manager) |h| {
var report = protocol.ChildAdded{
.parent = node_id,
.bus_address = entry.device_id,
.identity = 0,
.device_id = entry.device_id,
};
@memcpy(report.hid[0..entry.hid_len], entry.hid[0..entry.hid_len]);
var reply: [protocol.message_maximum]u8 = undefined;
_ = runtime.ipc.call(h, std.mem.asBytes(&report), &reply) catch {};
}
}
writeLine("acpi: reported {d} device(s) to the manager\n", .{registered_count});
// Stay resident: the claim holds, and the service is here to grow into the
// supervised discoverer (M20.3, then the M21 event side on the SCI).
@@ -135,11 +161,11 @@ pub fn main(init: runtime.process.Init) void {
/// Depth-first walk: register + report each present device with a _HID, then
/// descend. Scopes (\_SB, \_GPE …) are descended without producing a node.
fn walkDevices(node: *aml.Node, interpreter: *aml.Interpreter, manager: ?runtime.ipc.Handle, reported: *u32) void {
fn walkDevices(node: *aml.Node, interpreter: *aml.Interpreter) void {
var child = node.first_child;
while (child) |c| : (child = c.next_sibling) {
if (c.kind != .device) {
walkDevices(c, interpreter, manager, reported);
walkDevices(c, interpreter);
continue;
}
if (!devicePresent(interpreter, c)) continue; // absent: skip it and its subtree
@@ -148,14 +174,15 @@ fn walkDevices(node: *aml.Node, interpreter: *aml.Interpreter, manager: ?runtime
// Skip PCI roots — pci-bus already reports PCI functions; ACPI adds
// only the non-PCI _HID devices (docs/m19-m20-plan.md M20.2).
if (!std.mem.eql(u8, hid[0..7], "PNP0A03") and !std.mem.eql(u8, hid[0..7], "PNP0A08")) {
registerAndReport(c, hid, interpreter, manager, reported);
registerDevice(c, hid, interpreter);
}
}
walkDevices(c, interpreter, manager, reported);
walkDevices(c, interpreter);
}
}
fn registerAndReport(node: *aml.Node, hid: [8]u8, interpreter: *aml.Interpreter, manager: ?runtime.ipc.Handle, reported: *u32) void {
fn registerDevice(node: *aml.Node, hid: [8]u8, interpreter: *aml.Interpreter) void {
if (registered_count >= registered.len) return;
var descriptor = std.mem.zeroes(device.DeviceDescriptor);
descriptor.class = @intFromEnum(device.DeviceClass.acpi_device);
descriptor.pci_class = device.no_pci_class;
@@ -164,24 +191,12 @@ fn registerAndReport(node: *aml.Node, hid: [8]u8, interpreter: *aml.Interpreter,
@memcpy(descriptor.hid[0..@intCast(hid_len)], hid[0..@intCast(hid_len)]);
applyCrs(&descriptor, node, interpreter);
const registered = device.register(node_id, &descriptor) orelse {
const id = device.register(node_id, &descriptor) orelse {
writeLine("acpi: register refused for {s}\n", .{hid[0..@intCast(hid_len)]});
return;
};
writeLine("acpi: reported {s} (device {d}, {d} resources)\n", .{ hid[0..@intCast(hid_len)], registered, descriptor.resource_count });
reported.* += 1;
if (manager) |h| {
var report = protocol.ChildAdded{
.parent = node_id,
.bus_address = registered,
.identity = 0,
.device_id = registered,
};
@memcpy(report.hid[0..@intCast(hid_len)], hid[0..@intCast(hid_len)]);
var reply: [protocol.message_maximum]u8 = undefined;
_ = runtime.ipc.call(h, std.mem.asBytes(&report), &reply) catch {};
}
registered[registered_count] = .{ .hid = hid, .hid_len = @intCast(hid_len), .device_id = id, .resource_count = descriptor.resource_count };
registered_count += 1;
}
/// _STA bit 0 (present); absent method or a failed evaluation is treated as