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reorg: move device data modules into library/device/<domain>/

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First step of the device-code reorganization (plan: group device code by
domain, split each domain into a shareable data module + a logic module).
This moves the pure-data modules — the enums, wire types, and taxonomies
that any layer including the kernel can import cheaply — out of
system/devices/ and into their domain home:

  device-abi  -> library/device/model/device-abi.zig
  pci-class   -> library/device/pci/pci-class.zig
  usb-abi     -> library/device/usb/usb-abi.zig
  usb-ids     -> library/device/usb/usb-ids.zig
  acpi-ids    -> library/device/acpi/acpi-ids.zig
  aml/        -> library/device/acpi/aml/

Module names are unchanged, so this is a pure file move: only the
b.addModule paths and the host-test file list in build.zig change; no
importer is touched. system/devices/ now holds only the kernel-internal
device model (device-model, platform, acpi, device-tree, power).

The device *logic* (the pci Function helper, the usb transfer client) and
the kernel's cosmetic taxonomy dependency are handled in following commits.

zig build + zig build test green.
This commit is contained in:
Daniel Samson
2026-07-22 20:36:24 +01:00
parent ea470afe84
commit 794a8b5782
11 changed files with 12 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files
library/device/acpi/aml/aml.zig
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//! AML (ACPI Machine Language) — the bytecode in the DSDT and SSDTs that describes
//! the parts of the machine the static tables don't.
//!
//! This module has two stages. `parser.zig` walks the entire byte stream and
//! records every named object into a namespace tree (`namespace.zig`), capturing
//! method bodies and field/region layout. `interpreter.zig` then *evaluates* control
//! methods on demand — running operators, control flow, and OperationRegion field
//! access — so callers can resolve device status (`_STA`), current resource
//! settings (`_CRS`), sleep states (`_Sx`), and the like against the live namespace.
const std = @import("std");
const opcode = @import("opcodes.zig");
const parser = @import("parser.zig");
/// The named AML opcode/prefix bytes (`zero_opcode`, `byte_prefix`, …). Re-exported so
/// callers that decode raw AML bytes — e.g. the acpi service reading a `_HID` integer —
/// name the opcodes instead of writing bare 0x0A/0x0B/… literals (docs/coding-standards.md).
pub const opcodes = @import("opcodes.zig");
pub const Namespace = @import("namespace.zig").Namespace;
pub const Node = @import("namespace.zig").Node;
pub const NodeKind = @import("namespace.zig").NodeKind;
/// The AML evaluator: interprets control methods (and reads Names/Fields) far
/// enough for device discovery. See `interpreter.zig`.
pub const Interpreter = @import("interpreter.zig").Interpreter;
pub const Object = @import("interpreter.zig").Object;
pub const EvaluateHal = @import("interpreter.zig").Hal;
/// The SLP_TYP values written to PM1a/PM1b control to enter a sleep state.
pub const SleepType = struct {
slp_typ_a: u8,
slp_typ_b: u8,
};
pub const ParseResult = struct {
namespace: Namespace,
/// Bytes the parser consumed across all blocks...
consumed: usize,
/// ...out of this many. A clean full traversal has `consumed == total`.
total: usize,
};
/// Parse the given AML blocks (DSDT first, then SSDTs) into one namespace. Later
/// blocks extend the namespace built by earlier ones, exactly as ACPI intends.
pub fn parse(allocator: std.mem.Allocator, blocks: []const []const u8) !ParseResult {
var namespace = try Namespace.init(allocator);
var consumed: usize = 0;
var total: usize = 0;
for (blocks) |block| {
var p = parser.Parser.init(block, &namespace);
consumed += p.parseAll();
total += block.len;
}
return .{ .namespace = namespace, .consumed = consumed, .total = total };
}
/// Count the Device objects in a parsed namespace — what the acpi service
/// (docs/discovery.md) reports, and what the kernel's own parse counts
/// so the two can be checked equal across the ring-3 move.
pub fn deviceCount(namespace: *const Namespace) usize {
return countKind(namespace.root, .device);
}
fn countKind(node: *const Node, kind: NodeKind) usize {
var n: usize = if (node.kind == kind) 1 else 0;
var c = node.first_child;
while (c) |child| : (c = child.next_sibling) n += countKind(child, kind);
return n;
}
/// Look up the `\_S{state}` sleep package in a parsed namespace and return its
/// first two integer elements (SLP_TYP for PM1a / PM1b), or null if absent.
pub fn sleepState(namespace: *Namespace, state: u8) ?SleepType {
const segment = [4]u8{ '_', 'S', '0' + state, '_' };
const node = namespace.resolve(namespace.root, false, 0, &.{segment}) orelse return null;
if (node.kind != .name) return null;
return parseSleepPackage(node.value);
}
/// Decode a `Package(){ SLP_TYPa, SLP_TYPb, ... }` from the raw AML of a Name's
/// value. Returns the first two elements as bytes (missing elements default to 0).
fn parseSleepPackage(value: []const u8) ?SleepType {
if (value.len == 0 or value[0] != opcode.package_opcode) return null;
var p: usize = 1;
p += packageLengthSize(value, p) orelse return null;
if (p >= value.len) return null;
const number_elements = value[p];
p += 1;
const a: u8 = if (number_elements >= 1) @truncate(readInteger(value, &p) orelse 0) else 0;
const b: u8 = if (number_elements >= 2) @truncate(readInteger(value, &p) orelse 0) else 0;
return .{ .slp_typ_a = a, .slp_typ_b = b };
}
/// Bytes a PkgLength field occupies at `p` (we only need to step over it here).
fn packageLengthSize(bytes: []const u8, p: usize) ?usize {
if (p >= bytes.len) return null;
const follow: usize = bytes[p] >> 6;
if (p + 1 + follow > bytes.len) return null;
return 1 + follow;
}
/// Read one AML integer data object at `p`, advancing `p`.
fn readInteger(bytes: []const u8, p: *usize) ?u64 {
if (p.* >= bytes.len) return null;
const opcode_byte = bytes[p.*];
p.* += 1;
return switch (opcode_byte) {
opcode.zero_opcode => 0,
opcode.one_opcode => 1,
opcode.ones_opcode => 0xFF,
opcode.byte_prefix => readLittle(bytes, p, 1),
opcode.word_prefix => readLittle(bytes, p, 2),
opcode.dword_prefix => readLittle(bytes, p, 4),
opcode.qword_prefix => readLittle(bytes, p, 8),
else => null,
};
}
fn readLittle(bytes: []const u8, p: *usize, n: usize) ?u64 {
if (p.* + n > bytes.len) return null;
var v: u64 = 0;
var k: usize = 0;
while (k < n) : (k += 1) v |= @as(u64, bytes[p.* + k]) << @intCast(k * 8);
p.* += n;
return v;
}
// --- tests ------------------------------------------------------------------
test "parses a nested namespace and finds the sleep package" {
// A hand-assembled AML blob (all PkgLengths computed to be single-byte):
// Name(_S5, Package(2){0x05, 0x00})
// Scope(\_SB) { Device(PCI0) {
// Name(_HID, 0x11)
// Method(MTHD, 1) {}
// Method(CALL, 0) { MTHD(Zero) } // invocation of a 1-arg method
// } }
// OperationRegion(DBG0, SystemIO, 0x0402, 1)
// Field(DBG0, ...) { DBGB, 8 }
const blob = [_]u8{
// Name(_S5, Package(2){Byte 0x05, Byte 0x00})
0x08, 0x5F, 0x53, 0x35, 0x5F, 0x12, 0x06, 0x02, 0x0A, 0x05, 0x0A, 0x00,
// Scope(\_SB) packagelen=0x27
0x10, 0x27, 0x5C, 0x5F, 0x53, 0x42, 0x5F,
// Device(PCI0) packagelen=0x1F
0x5B, 0x82, 0x1F, 0x50, 0x43,
0x49, 0x30,
// Name(_HID, 0x11)
0x08, 0x5F, 0x48, 0x49, 0x44, 0x0A, 0x11,
// Method(MTHD, flags=1) empty, packagelen=0x06
0x14, 0x06, 0x4D,
0x54, 0x48, 0x44, 0x01,
// Method(CALL, flags=0) { MTHD(Zero) }, packagelen=0x0B
0x14, 0x0B, 0x43, 0x41, 0x4C, 0x4C, 0x00, 0x4D,
0x54, 0x48, 0x44, 0x00,
// OperationRegion(DBG0, SystemIO, Word 0x0402, Byte 1)
0x5B, 0x80, 0x44, 0x42, 0x47, 0x30, 0x01, 0x0B,
0x02, 0x04, 0x0A, 0x01,
// Field(DBG0, flags=1) { DBGB, 8 }, packagelen=0x0B
0x5B, 0x81, 0x0B, 0x44, 0x42, 0x47, 0x30, 0x01,
0x44, 0x42, 0x47, 0x42, 0x08,
};
var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
defer arena.deinit();
var result = try parse(arena.allocator(), &.{&blob});
// Integrity: the parser consumed exactly the whole blob (no desync).
try std.testing.expectEqual(blob.len, result.consumed);
try std.testing.expectEqual(blob.len, result.total);
const namespace = &result.namespace;
// Expected top-level nodes.
const sb = namespace.resolve(namespace.root, false, 0, &.{.{ '_', 'S', 'B', '_' }}) orelse return error.NoSB;
try std.testing.expectEqual(NodeKind.scope, sb.kind);
const pci0 = namespace.resolve(sb, false, 0, &.{.{ 'P', 'C', 'I', '0' }}) orelse return error.NoPCI0;
try std.testing.expectEqual(NodeKind.device, pci0.kind);
_ = namespace.resolve(pci0, false, 0, &.{.{ '_', 'H', 'I', 'D' }}) orelse return error.NoHID;
// The 1-arg method's arg count was parsed from its flags byte.
const mthd = namespace.resolve(pci0, false, 0, &.{.{ 'M', 'T', 'H', 'D' }}) orelse return error.NoMTHD;
try std.testing.expectEqual(NodeKind.method, mthd.kind);
try std.testing.expectEqual(@as(u8, 1), mthd.arg_count);
// OperationRegion and the Field unit made it into the namespace.
_ = namespace.resolve(namespace.root, false, 0, &.{.{ 'D', 'B', 'G', '0' }}) orelse return error.NoRegion;
_ = namespace.resolve(namespace.root, false, 0, &.{.{ 'D', 'B', 'G', 'B' }}) orelse return error.NoField;
// The sleep package decoded.
const s5 = sleepState(namespace, 5) orelse return error.NoS5;
try std.testing.expectEqual(@as(u8, 5), s5.slp_typ_a);
try std.testing.expectEqual(@as(u8, 0), s5.slp_typ_b);
}
fn noMap(physical: u64, _: u64, _: bool) u64 {
return physical;
}
fn noRead(_: u8, _: u16) u32 {
return 0;
}
fn noWrite(_: u8, _: u16, _: u32) void {}
test "interpreter runs a method with args, arithmetic, and control flow" {
// Method(TST_, 1) {
// Store(Arg0, Local0); Add(Local0, 5, Local0)
// If (LGreater(Local0, 10)) { Return(One) }
// Return(Zero)
// }
const blob = [_]u8{
0x14, 0x18, 0x54, 0x53, 0x54, 0x5F, 0x01, // Method TST_, 1 arg
0x70, 0x68, 0x60, // Store(Arg0, Local0)
0x72, 0x60, 0x0A, 0x05, 0x60, // Add(Local0, 5, Local0)
0xA0, 0x07, 0x94, 0x60, 0x0A, 0x0A, 0xA4, 0x01, // If(LGreater(Local0,10)) { Return(One) }
0xA4, 0x00, // Return(Zero)
};
var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
defer arena.deinit();
var result = try parse(arena.allocator(), &.{&blob});
const namespace = &result.namespace;
const tst = namespace.resolve(namespace.root, false, 0, &.{.{ 'T', 'S', 'T', '_' }}) orelse return error.NoMethod;
var interpreter = Interpreter.init(namespace, .{ .mapMmio = noMap, .pioRead = noRead, .pioWrite = noWrite }, arena.allocator());
const hi = try interpreter.evaluate(tst, &.{.{ .integer = 7 }}); // 7+5=12 > 10 -> 1
try std.testing.expectEqual(@as(u64, 1), try hi.asInteger());
const lo = try interpreter.evaluate(tst, &.{.{ .integer = 2 }}); // 2+5=7 !> 10 -> 0
try std.testing.expectEqual(@as(u64, 0), try lo.asInteger());
}
test "interpreter records Notify(device, code)" {
// Device(DEV_) { Name(_HID, 0x030AD041) } // PNP0A03-ish placeholder
// Method(TST_, 0) { Notify(DEV_, 0x80); Return(Zero) }
// Encoded: a Device holding a Name, then a Method issuing Notify on it.
const blob = [_]u8{
0x5B, 0x82, 0x0F, 0x44, 0x45, 0x56, 0x5F, // Device(DEV_) len=0x0F (pkglen + DEV_ + Name)
0x08, 0x5F, 0x48, 0x49, 0x44, 0x0C, 0x41, 0xD0, 0x0A, 0x03, // Name(_HID, DWord 0x030AD041)
0x14, 0x0F, 0x54, 0x53, 0x54, 0x5F, 0x00, // Method(TST_, 0) len=0x0F (pkglen + TST_ + flags + body)
0x86, 0x44, 0x45, 0x56, 0x5F, 0x0A, 0x80, // Notify(DEV_, 0x80)
0xA4, 0x00, // Return(Zero)
};
var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
defer arena.deinit();
var result = try parse(arena.allocator(), &.{&blob});
const namespace = &result.namespace;
const tst = namespace.resolve(namespace.root, false, 0, &.{.{ 'T', 'S', 'T', '_' }}) orelse return error.NoMethod;
const dev = namespace.resolve(namespace.root, false, 0, &.{.{ 'D', 'E', 'V', '_' }}) orelse return error.NoDevice;
var interpreter = Interpreter.init(namespace, .{ .mapMmio = noMap, .pioRead = noRead, .pioWrite = noWrite }, arena.allocator());
_ = try interpreter.evaluate(tst, &.{});
const events = interpreter.takeNotifications();
try std.testing.expectEqual(@as(usize, 1), events.len);
try std.testing.expectEqual(dev, events[0].node);
try std.testing.expectEqual(@as(u64, 0x80), events[0].code);
}
library/device/acpi/aml/interpreter.zig
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//! A tree-walking AML interpreter — the evaluation stage on top of the parser's
//! structural namespace. It executes control methods (their bodies captured by
//! the parser) far enough to serve device discovery: device status (`_STA`, is a
//! device present), current resource settings (`_CRS`), and the operators, control
//! flow, locals/args, and
//! OperationRegion field access those methods reach for.
//!
//! Scope: integers, buffers, strings, packages, and references; If/Else/While/
//! Return; the arithmetic/logic operators; method invocation; Name/Local/Arg
//! access; CreateField buffer patching (the common current-resource-settings
//! (`_CRS`) idiom); and field
//! reads/writes against SystemMemory and SystemIO regions. Opcodes outside this
//! set return `error.Unsupported`, which callers treat as "couldn't evaluate" and
//! fall back — never a hard failure.
const std = @import("std");
const opcode = @import("opcodes.zig");
const Node = @import("namespace.zig").Node;
const Namespace = @import("namespace.zig").Namespace;
/// Injected hardware access for OperationRegion reads/writes (the architecture VMM + pio).
pub const Hal = struct {
mapMmio: *const fn (physical: u64, len: u64, writable: bool) u64,
pioRead: *const fn (width: u8, port: u16) u32,
pioWrite: *const fn (width: u8, port: u16, value: u32) void,
};
pub const Error = error{ Unsupported, Truncated, DivByZero } || std.mem.Allocator.Error;
/// A runtime AML value.
pub const Object = union(enum) {
uninitialized,
integer: u64,
buffer: []u8,
string: []u8,
package: []Object,
reference: *Node,
pub fn asInteger(self: Object) Error!u64 {
return switch (self) {
.integer => |v| v,
.buffer => |b| blk: {
var v: u64 = 0;
for (b, 0..) |byte, i| {
if (i >= 8) break;
v |= @as(u64, byte) << @intCast(i * 8);
}
break :blk v;
},
else => error.Unsupported,
};
}
};
const maximum_segments = 16;
const NamePath = struct {
rooted: bool = false,
parents: u8 = 0,
segments: [maximum_segments][4]u8 = undefined,
count: usize = 0,
fn slice(self: *const NamePath) []const [4]u8 {
return self.segments[0..self.count];
}
};
const Cursor = struct {
b: []const u8,
i: usize = 0,
fn eof(self: *Cursor) bool {
return self.i >= self.b.len;
}
fn peek(self: *Cursor) ?u8 {
return if (self.eof()) null else self.b[self.i];
}
fn byte(self: *Cursor) Error!u8 {
if (self.eof()) return error.Truncated;
const v = self.b[self.i];
self.i += 1;
return v;
}
fn take(self: *Cursor, n: usize) Error![]const u8 {
if (self.i + n > self.b.len) return error.Truncated;
const s = self.b[self.i .. self.i + n];
self.i += n;
return s;
}
fn packageLength(self: *Cursor) Error!usize {
const lead = try self.byte();
const follow: usize = lead >> 6;
if (follow == 0) return lead & 0x3F;
var value: usize = lead & 0x0F;
var k: usize = 0;
while (k < follow) : (k += 1) value |= @as(usize, try self.byte()) << @intCast(4 + k * 8);
return value;
}
fn nameString(self: *Cursor) Error!NamePath {
var name_path = NamePath{};
if (self.peek() == opcode.root_char) {
name_path.rooted = true;
self.i += 1;
} else {
while (self.peek() == opcode.parent_prefix_char) : (self.i += 1) name_path.parents += 1;
}
const lead = self.peek() orelse return name_path;
switch (lead) {
0x00 => self.i += 1,
opcode.dual_name_prefix => {
self.i += 1;
try self.segment(&name_path);
try self.segment(&name_path);
},
opcode.multi_name_prefix => {
self.i += 1;
const count = try self.byte();
var k: usize = 0;
while (k < count) : (k += 1) try self.segment(&name_path);
},
else => try self.segment(&name_path),
}
return name_path;
}
fn segment(self: *Cursor, name_path: *NamePath) Error!void {
const s = try self.take(4);
if (name_path.count < maximum_segments) {
name_path.segments[name_path.count] = s[0..4].*;
name_path.count += 1;
}
}
};
const Frame = struct {
args: [7]Object = .{.uninitialized} ** 7,
locals: [8]Object = .{.uninitialized} ** 8,
scope: *Node,
ret: Object = .uninitialized,
returned: bool = false,
broke: bool = false,
};
/// A CreateField binding: a name that indexes into a buffer object.
const BufferField = struct { buffer: *Node, byte_off: usize, bit_width: u32 };
/// One Notify(device, code) the interpreter executed.
pub const NotifyEvent = struct { node: *Node, code: u64 };
pub const Interpreter = struct {
namespace: *Namespace,
hal: Hal,
arena: std.mem.Allocator,
/// Runtime object overrides for Name nodes (Store targets, patched buffers).
dynamic_overrides: std.AutoHashMapUnmanaged(*Node, Object) = .{},
/// CreateField bindings active for the current evaluation.
fields: std.AutoHashMapUnmanaged(*Node, BufferField) = .{},
/// Notify(device, code) operations the last evaluation executed — a GPE or
/// EC handler tells the OS "look at this device" this way. Bounded; the
/// caller drains it with `takeNotifications` after `evaluate` (M21).
notify_queue: [16]NotifyEvent = undefined,
notify_count: usize = 0,
pub fn init(namespace: *Namespace, hal: Hal, arena: std.mem.Allocator) Interpreter {
return .{ .namespace = namespace, .hal = hal, .arena = arena };
}
/// Evaluate a namespace object: invoke a Method, read a Name's value, or read a
/// Field. Resets per-evaluation runtime state first.
pub fn evaluate(self: *Interpreter, node: *Node, args: []const Object) Error!Object {
self.notify_count = 0;
self.dynamic_overrides.clearRetainingCapacity();
self.fields.clearRetainingCapacity();
return self.invoke(node, args);
}
fn invoke(self: *Interpreter, node: *Node, args: []const Object) Error!Object {
switch (node.kind) {
.method => {
var frame = Frame{ .scope = node };
for (args, 0..) |a, i| {
if (i < frame.args.len) frame.args[i] = a;
}
var current = Cursor{ .b = node.value };
try self.executeList(&current, &frame);
return frame.ret;
},
.name => {
if (self.dynamic_overrides.get(node)) |o| return o;
var current = Cursor{ .b = node.value };
var frame = Frame{ .scope = node.parent orelse self.namespace.root };
return self.term(&current, &frame);
},
.field => return .{ .integer = try self.readField(node) },
else => return .{ .reference = node },
}
}
/// Execute a TermList until it ends or the frame returns/breaks.
fn executeList(self: *Interpreter, current: *Cursor, frame: *Frame) Error!void {
while (!current.eof() and !frame.returned and !frame.broke) {
_ = try self.term(current, frame);
}
}
/// Evaluate/execute one term, returning its value (`.uninitialized` for pure
/// statements).
fn term(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const lead = current.peek() orelse return error.Truncated;
if (isNameStart(lead)) return self.nameReference(current, frame);
_ = try current.byte();
return switch (lead) {
opcode.zero_opcode => Object{ .integer = 0 },
opcode.one_opcode => Object{ .integer = 1 },
opcode.ones_opcode => Object{ .integer = ~@as(u64, 0) },
opcode.byte_prefix => Object{ .integer = try self.readConstant(current, 1) },
opcode.word_prefix => Object{ .integer = try self.readConstant(current, 2) },
opcode.dword_prefix => Object{ .integer = try self.readConstant(current, 4) },
opcode.qword_prefix => Object{ .integer = try self.readConstant(current, 8) },
opcode.string_prefix => try self.readString(current),
opcode.buffer_opcode => try self.buffer(current, frame),
opcode.package_opcode, opcode.var_package_opcode => try self.package(current, frame, lead == opcode.var_package_opcode),
opcode.local0_opcode...opcode.local7_opcode => frame.locals[lead - opcode.local0_opcode],
opcode.arg0_opcode...opcode.arg6_opcode => frame.args[lead - opcode.arg0_opcode],
opcode.return_opcode => blk: {
frame.ret = try self.term(current, frame);
frame.returned = true;
break :blk .uninitialized;
},
opcode.break_opcode => blk: {
frame.broke = true;
break :blk .uninitialized;
},
opcode.continue_opcode, opcode.noop_opcode => .uninitialized,
opcode.if_opcode => try self.ifElse(current, frame),
opcode.while_opcode => try self.whileLoop(current, frame),
opcode.store_opcode => try self.store(current, frame),
opcode.increment_opcode => try self.incDec(current, frame, 1),
opcode.decrement_opcode => try self.incDec(current, frame, -1),
opcode.add_opcode => try self.binary(current, frame, .add),
opcode.subtract_opcode => try self.binary(current, frame, .sub),
opcode.multiply_opcode => try self.binary(current, frame, .mul),
opcode.mod_opcode => try self.binary(current, frame, .mod),
opcode.and_opcode => try self.binary(current, frame, .band),
opcode.or_opcode => try self.binary(current, frame, .bor),
opcode.xor_opcode => try self.binary(current, frame, .bxor),
opcode.nand_opcode => try self.binary(current, frame, .nand),
opcode.nor_opcode => try self.binary(current, frame, .nor),
opcode.shift_left_opcode => try self.binary(current, frame, .shl),
opcode.shift_right_opcode => try self.binary(current, frame, .shr),
opcode.divide_opcode => try self.divide(current, frame),
opcode.land_opcode => try self.logic2(current, frame, .land),
opcode.lor_opcode => try self.logic2(current, frame, .lor),
opcode.lequal_opcode => try self.logic2(current, frame, .eq),
opcode.lgreater_opcode => try self.logic2(current, frame, .gt),
opcode.lless_opcode => try self.logic2(current, frame, .lt),
opcode.lnot_opcode => try self.lnot(current, frame),
opcode.not_opcode => blk: {
const v = try self.evaluateInteger(current, frame);
const r = ~v;
try self.storeTarget(current, frame, .{ .integer = r });
break :blk .{ .integer = r };
},
opcode.size_of_opcode => try self.sizeOf(current, frame),
opcode.index_opcode => try self.index(current, frame),
opcode.dereference_of_opcode => try self.dereferenceOf(current, frame),
opcode.to_integer_opcode => blk: {
const v = try self.evaluateInteger(current, frame);
try self.storeTarget(current, frame, .{ .integer = v });
break :blk .{ .integer = v };
},
opcode.to_buffer_opcode => try self.passThroughUnary(current, frame),
opcode.notify_opcode => try self.notify(current, frame),
opcode.extended_opcode_prefix => try self.ext(current, frame),
// CreateXField: source, index, name (bit widths differ by op)
opcode.create_bit_field_opcode => try self.createField(current, frame, 1),
opcode.create_byte_field_opcode => try self.createField(current, frame, 8),
opcode.create_word_field_opcode => try self.createField(current, frame, 16),
opcode.create_dword_field_opcode => try self.createField(current, frame, 32),
opcode.create_qword_field_opcode => try self.createField(current, frame, 64),
else => error.Unsupported,
};
}
// --- name references ----------------------------------------------------
fn nameReference(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const name_path = try current.nameString();
const node = self.namespace.resolve(frame.scope, name_path.rooted, name_path.parents, name_path.slice()) orelse
return .uninitialized; // unknown name -> treat as uninitialised
switch (node.kind) {
.method => {
var argbuf: [7]Object = undefined;
var i: usize = 0;
while (i < node.arg_count and i < argbuf.len) : (i += 1) argbuf[i] = try self.term(current, frame);
return self.invoke(node, argbuf[0..@min(node.arg_count, argbuf.len)]);
},
.field => return .{ .integer = try self.readField(node) },
.name => return self.invoke(node, &.{}),
else => return .{ .reference = node },
}
}
// --- data objects -------------------------------------------------------
fn readConstant(self: *Interpreter, current: *Cursor, n: usize) Error!u64 {
_ = self;
const bytes = try current.take(n);
var v: u64 = 0;
for (bytes, 0..) |b, i| v |= @as(u64, b) << @intCast(i * 8);
return v;
}
fn readString(self: *Interpreter, current: *Cursor) Error!Object {
const start = current.i;
while (current.peek()) |c| {
current.i += 1;
if (c == 0) break;
}
const raw = current.b[start .. current.i - 1];
const s = try self.arena.dupe(u8, raw);
return .{ .string = s };
}
fn buffer(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const start = current.i;
const len = try current.packageLength();
const end = @min(start + len, current.b.len);
const size = try self.evaluateInteger(current, frame);
const data = current.b[@min(current.i, end)..end];
const bytes = try self.arena.alloc(u8, @intCast(size));
@memset(bytes, 0);
@memcpy(bytes[0..@min(bytes.len, data.len)], data[0..@min(bytes.len, data.len)]);
current.i = end;
return .{ .buffer = bytes };
}
fn package(self: *Interpreter, current: *Cursor, frame: *Frame, variable: bool) Error!Object {
const start = current.i;
const len = try current.packageLength();
const end = @min(start + len, current.b.len);
const count: usize = if (variable) @intCast(try self.evaluateInteger(current, frame)) else try current.byte();
const elems = try self.arena.alloc(Object, count);
var i: usize = 0;
while (i < count and current.i < end) : (i += 1) elems[i] = try self.term(current, frame);
while (i < count) : (i += 1) elems[i] = .uninitialized;
current.i = end;
return .{ .package = elems };
}
// --- operators ----------------------------------------------------------
const BinaryOperation = enum { add, sub, mul, mod, band, bor, bxor, nand, nor, shl, shr };
fn binary(self: *Interpreter, current: *Cursor, frame: *Frame, kind: BinaryOperation) Error!Object {
const a = try self.evaluateInteger(current, frame);
const b = try self.evaluateInteger(current, frame);
const r: u64 = switch (kind) {
.add => a +% b,
.sub => a -% b,
.mul => a *% b,
.mod => if (b == 0) return error.DivByZero else a % b,
.band => a & b,
.bor => a | b,
.bxor => a ^ b,
.nand => ~(a & b),
.nor => ~(a | b),
.shl => if (b >= 64) 0 else a << @intCast(b),
.shr => if (b >= 64) 0 else a >> @intCast(b),
};
try self.storeTarget(current, frame, .{ .integer = r });
return .{ .integer = r };
}
fn divide(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const a = try self.evaluateInteger(current, frame);
const b = try self.evaluateInteger(current, frame);
if (b == 0) return error.DivByZero;
try self.storeTarget(current, frame, .{ .integer = a % b }); // remainder target
try self.storeTarget(current, frame, .{ .integer = a / b }); // quotient target
return .{ .integer = a / b };
}
const LogicOperation = enum { land, lor, eq, gt, lt };
fn logic2(self: *Interpreter, current: *Cursor, frame: *Frame, kind: LogicOperation) Error!Object {
const a = try self.evaluateInteger(current, frame);
const b = try self.evaluateInteger(current, frame);
const r = switch (kind) {
.land => a != 0 and b != 0,
.lor => a != 0 or b != 0,
.eq => a == b,
.gt => a > b,
.lt => a < b,
};
return .{ .integer = if (r) ~@as(u64, 0) else 0 };
}
fn lnot(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
// 0x92 0x93/94/95 are the compound comparisons.
const b = current.peek() orelse return error.Truncated;
switch (b) {
opcode.lnot.not_equal => {
current.i += 1;
const x = try self.evaluateInteger(current, frame);
const y = try self.evaluateInteger(current, frame);
return .{ .integer = if (x != y) ~@as(u64, 0) else 0 };
},
opcode.lnot.less_equal => {
current.i += 1;
const x = try self.evaluateInteger(current, frame);
const y = try self.evaluateInteger(current, frame);
return .{ .integer = if (x <= y) ~@as(u64, 0) else 0 };
},
opcode.lnot.greater_equal => {
current.i += 1;
const x = try self.evaluateInteger(current, frame);
const y = try self.evaluateInteger(current, frame);
return .{ .integer = if (x >= y) ~@as(u64, 0) else 0 };
},
else => {
const x = try self.evaluateInteger(current, frame);
return .{ .integer = if (x == 0) ~@as(u64, 0) else 0 };
},
}
}
fn incDec(self: *Interpreter, current: *Cursor, frame: *Frame, delta: i64) Error!Object {
// Operand is a SuperName that is both read and written.
const save = current.i;
const current_value = try self.term(current, frame);
const v = try current_value.asInteger();
const r = if (delta > 0) v +% 1 else v -% 1;
var tcur = Cursor{ .b = current.b, .i = save };
try self.storeInto(&tcur, frame, .{ .integer = r });
return .{ .integer = r };
}
fn sizeOf(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const o = try self.term(current, frame);
return .{ .integer = switch (o) {
.buffer => |b| b.len,
.string => |s| s.len,
.package => |p| p.len,
else => 0,
} };
}
fn passThroughUnary(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const o = try self.term(current, frame);
try self.storeTarget(current, frame, o);
return o;
}
fn index(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const source = try self.term(current, frame);
const element_index: usize = @intCast(try self.evaluateInteger(current, frame));
// Optional target (a reference); we don't materialise references, so store
// the indexed value if a target is present.
const value: Object = switch (source) {
.buffer => |b| .{ .integer = if (element_index < b.len) b[element_index] else 0 },
.package => |p| if (element_index < p.len) p[element_index] else .uninitialized,
.string => |s| .{ .integer = if (element_index < s.len) s[element_index] else 0 },
else => .uninitialized,
};
try self.storeTarget(current, frame, value);
return value;
}
fn dereferenceOf(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const o = try self.term(current, frame);
return switch (o) {
.reference => |n| self.invoke(n, &.{}),
else => o,
};
}
// --- control flow -------------------------------------------------------
fn ifElse(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const start = current.i;
const end = @min(start + try current.packageLength(), current.b.len);
const cond = try self.evaluateInteger(current, frame);
if (cond != 0) {
var body = Cursor{ .b = current.b[0..end], .i = current.i };
try self.executeList(&body, frame);
current.i = end;
// Skip a trailing Else.
if (current.peek() == opcode.else_opcode) {
current.i += 1;
const es = current.i;
const ee = @min(es + try current.packageLength(), current.b.len);
current.i = ee;
}
} else {
current.i = end;
if (current.peek() == opcode.else_opcode) {
current.i += 1;
const es = current.i;
const ee = @min(es + try current.packageLength(), current.b.len);
var body = Cursor{ .b = current.b[0..ee], .i = current.i };
try self.executeList(&body, frame);
current.i = ee;
}
}
return .uninitialized;
}
fn whileLoop(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const start = current.i;
const end = @min(start + try current.packageLength(), current.b.len);
const pred_at = current.i;
var guard: usize = 0;
while (guard < 100_000) : (guard += 1) {
var pc = Cursor{ .b = current.b[0..end], .i = pred_at };
const cond = try self.evaluateInteger(&pc, frame);
if (cond == 0) break;
var body = Cursor{ .b = current.b[0..end], .i = pc.i };
try self.executeList(&body, frame);
if (frame.returned) break;
if (frame.broke) {
frame.broke = false;
break;
}
}
current.i = end;
return .uninitialized;
}
// --- store --------------------------------------------------------------
fn store(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const value = try self.term(current, frame);
try self.storeInto(current, frame, value);
return value;
}
/// A Store *target* that may be NullName (no store).
fn storeTarget(self: *Interpreter, current: *Cursor, frame: *Frame, value: Object) Error!void {
if (current.peek() == 0x00) {
current.i += 1; // NullName
return;
}
try self.storeInto(current, frame, value);
}
/// Notify(SuperName, NotifyValue): resolve the named device, evaluate the
/// code, and record the pair for the caller to dispatch. AML control flow
/// continues (Notify returns nothing).
fn notify(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const lead = current.peek() orelse return error.Truncated;
var target: ?*Node = null;
if (isNameStart(lead)) {
const name_path = try current.nameString();
target = self.namespace.resolve(frame.scope, name_path.rooted, name_path.parents, name_path.slice());
} else {
// A non-name SuperName (Local/Arg holding a reference).
const obj = try self.term(current, frame);
if (obj == .reference) target = obj.reference;
}
const code = try self.evaluateInteger(current, frame);
if (target) |node| {
if (self.notify_count < self.notify_queue.len) {
self.notify_queue[self.notify_count] = .{ .node = node, .code = code };
self.notify_count += 1;
}
}
return .uninitialized;
}
/// The Notify events the last `evaluate` produced. Valid until the next
/// `evaluate` clears the queue.
pub fn takeNotifications(self: *Interpreter) []const NotifyEvent {
return self.notify_queue[0..self.notify_count];
}
fn storeInto(self: *Interpreter, current: *Cursor, frame: *Frame, value: Object) Error!void {
const lead = current.peek() orelse return error.Truncated;
if (isNameStart(lead)) {
const name_path = try current.nameString();
const node = self.namespace.resolve(frame.scope, name_path.rooted, name_path.parents, name_path.slice()) orelse return;
if (self.fields.get(node)) |buffer_field| {
try self.writeBufferField(buffer_field, try value.asInteger());
} else if (node.kind == .field) {
try self.writeField(node, try value.asInteger());
} else {
try self.dynamic_overrides.put(self.arena, node, value);
}
return;
}
_ = try current.byte();
switch (lead) {
0x00 => {}, // NullName
opcode.local0_opcode...opcode.local7_opcode => frame.locals[lead - opcode.local0_opcode] = value,
opcode.arg0_opcode...opcode.arg6_opcode => frame.args[lead - opcode.arg0_opcode] = value,
opcode.index_opcode => {
const source = try self.term(current, frame);
const element_index: usize = @intCast(try self.evaluateInteger(current, frame));
switch (source) {
.buffer => |b| if (element_index < b.len) {
b[element_index] = @truncate(try value.asInteger());
},
.package => |p| if (element_index < p.len) {
p[element_index] = value;
},
else => {},
}
},
else => return error.Unsupported,
}
}
// --- CreateField (buffer patching) --------------------------------------
fn createField(self: *Interpreter, current: *Cursor, frame: *Frame, bit_width: u32) Error!Object {
const source = try self.term(current, frame); // source buffer (as a reference or value)
const bit_index = try self.evaluateInteger(current, frame);
const name_path = try current.nameString();
const node = self.namespace.resolve(frame.scope, name_path.rooted, name_path.parents, name_path.slice()) orelse return .uninitialized;
// Bind the new name to the source buffer's node so stores land in it.
const buffer_node: *Node = switch (source) {
.reference => |n| n,
else => return .uninitialized,
};
// Materialise the buffer into `dynamic_overrides` so patches persist and are returned.
if (self.dynamic_overrides.get(buffer_node) == null) {
const value = try self.invoke(buffer_node, &.{});
try self.dynamic_overrides.put(self.arena, buffer_node, value);
}
const byte_off: usize = @intCast(bit_index / 8);
try self.fields.put(self.arena, node, .{ .buffer = buffer_node, .byte_off = byte_off, .bit_width = bit_width });
return .uninitialized;
}
fn writeBufferField(self: *Interpreter, buffer_field: BufferField, value: u64) Error!void {
const obj = self.dynamic_overrides.get(buffer_field.buffer) orelse return;
const bytes = switch (obj) {
.buffer => |b| b,
else => return,
};
const byte_count = (buffer_field.bit_width + 7) / 8;
var k: usize = 0;
while (k < byte_count and buffer_field.byte_off + k < bytes.len) : (k += 1) {
bytes[buffer_field.byte_off + k] = @truncate(value >> @intCast(k * 8));
}
}
// --- OperationRegion field access ---------------------------------------
fn readField(self: *Interpreter, field: *Node) Error!u64 {
const region = field.region orelse return error.Unsupported;
if (field.bit_width == 0 or field.bit_width > 64) return error.Unsupported;
const base = try self.regionBase(region);
const start_byte = base + field.bit_offset / 8;
const shift: u7 = @intCast(field.bit_offset % 8);
const total = @as(usize, shift) + field.bit_width;
const byte_count = (total + 7) / 8;
var raw: u128 = 0;
var k: usize = 0;
while (k < byte_count) : (k += 1) {
raw |= @as(u128, try self.readRegionByte(region.region_space, start_byte + k)) << @intCast(k * 8);
}
const masked = (raw >> shift) & bitMask(field.bit_width);
return @truncate(masked);
}
fn writeField(self: *Interpreter, field: *Node, value: u64) Error!void {
const region = field.region orelse return error.Unsupported;
if (field.bit_width == 0 or field.bit_width > 64) return error.Unsupported;
const base = try self.regionBase(region);
const start_byte = base + field.bit_offset / 8;
const shift: u7 = @intCast(field.bit_offset % 8);
const total = @as(usize, shift) + field.bit_width;
const byte_count = (total + 7) / 8;
// Read-modify-write byte by byte.
var raw: u128 = 0;
var k: usize = 0;
while (k < byte_count) : (k += 1) {
raw |= @as(u128, try self.readRegionByte(region.region_space, start_byte + k)) << @intCast(k * 8);
}
const mask = bitMask(field.bit_width) << shift;
raw = (raw & ~mask) | ((@as(u128, value) << shift) & mask);
k = 0;
while (k < byte_count) : (k += 1) {
try self.writeRegionByte(region.region_space, start_byte + k, @truncate(raw >> @intCast(k * 8)));
}
}
fn regionBase(self: *Interpreter, region: *Node) Error!u64 {
var current = Cursor{ .b = region.region_offset_aml };
var frame = Frame{ .scope = region.parent orelse self.namespace.root };
return (try self.term(&current, &frame)).asInteger();
}
fn readRegionByte(self: *Interpreter, space: u8, address: u64) Error!u8 {
switch (space) {
0 => { // SystemMemory
const virtual = self.hal.mapMmio(address & ~@as(u64, 0xFFF), 0x1000, true);
const p: *align(1) const volatile u8 = @ptrFromInt(virtual + (address & 0xFFF));
return p.*;
},
1 => return @truncate(self.hal.pioRead(1, @intCast(address & 0xFFFF))), // SystemIO
else => return error.Unsupported,
}
}
fn writeRegionByte(self: *Interpreter, space: u8, address: u64, value: u8) Error!void {
switch (space) {
0 => {
const virtual = self.hal.mapMmio(address & ~@as(u64, 0xFFF), 0x1000, true);
const p: *align(1) volatile u8 = @ptrFromInt(virtual + (address & 0xFFF));
p.* = value;
},
1 => self.hal.pioWrite(1, @intCast(address & 0xFFFF), value),
else => return error.Unsupported,
}
}
// --- extended opcodes ---------------------------------------------------
fn ext(self: *Interpreter, current: *Cursor, frame: *Frame) Error!Object {
const e = try current.byte();
switch (e) {
opcode.extended.debug => return .uninitialized,
opcode.extended.revision => return .{ .integer = 2 },
opcode.extended.timer => return .{ .integer = 0 },
// Mutex/Event ops are no-ops in this single-threaded evaluator.
opcode.extended.acquire => {
_ = try self.term(current, frame); // mutex SuperName
_ = try current.take(2); // timeout
return .{ .integer = 0 }; // acquired
},
opcode.extended.release, opcode.extended.reset, opcode.extended.signal => {
_ = try self.term(current, frame);
return .uninitialized;
},
opcode.extended.wait => {
_ = try self.term(current, frame);
_ = try self.term(current, frame);
return .{ .integer = 0 };
},
opcode.extended.sleep, opcode.extended.stall => {
_ = try self.term(current, frame);
return .uninitialized;
},
else => return error.Unsupported,
}
}
fn evaluateInteger(self: *Interpreter, current: *Cursor, frame: *Frame) Error!u64 {
return (try self.term(current, frame)).asInteger();
}
};
fn bitMask(width: u32) u128 {
if (width >= 128) return ~@as(u128, 0);
return (@as(u128, 1) << @intCast(width)) - 1;
}
fn isNameStart(b: u8) bool {
return (b >= opcode.name_char_start and b <= opcode.name_char_end) or
b == opcode.name_char_underscore or
b == opcode.root_char or
b == opcode.parent_prefix_char or
b == opcode.dual_name_prefix or
b == opcode.multi_name_prefix;
}
library/device/acpi/aml/namespace.zig
+181
View File
@@ -0,0 +1,181 @@
//! The ACPI namespace the AML parser builds: a tree of named nodes, plus the name
//! resolution rules the parser needs while it walks (so a method invocation can be
//! resolved to its declaration to learn its argument count).
//!
//! Nodes are individually allocated and linked intrusively (first-child /
//! next-sibling), the same shape as the device tree in `device.zig`.
const std = @import("std");
pub const NodeKind = enum {
root,
scope,
device,
method,
name,
region, // OperationRegion
field, // a Field unit
mutex,
event,
processor,
power_resource,
thermal_zone,
alias,
external,
other,
};
pub const Node = struct {
/// The 4-byte NameSeg identifying this node within its parent. The root uses
/// all-zero.
segment: [4]u8 = .{ 0, 0, 0, 0 },
kind: NodeKind = .other,
/// For Method / External: the declared argument count (0..7). Used to resolve
/// how many TermArgs a method invocation consumes.
arg_count: u8 = 0,
/// For Name: the AML bytes of its DataReferenceObject (so a value like a sleep
/// state's (`_Sx`) Package can be parsed on demand). For Method: the AML bytes of the body,
/// interpreted on demand by the evaluator. Empty otherwise.
value: []const u8 = &.{},
// OperationRegion metadata (kind == .region): the address space, plus the AML
// of the offset/length expressions (evaluated lazily, usually constants).
region_space: u8 = 0,
region_offset_aml: []const u8 = &.{},
region_len_aml: []const u8 = &.{},
// Field-unit metadata (kind == .field): which region it lives in and its bit
// position/width/access, so the evaluator can read/write it.
region: ?*Node = null,
bit_offset: u32 = 0,
bit_width: u32 = 0,
access_type: u8 = 0,
parent: ?*Node = null,
first_child: ?*Node = null,
next_sibling: ?*Node = null,
/// Depth-first count of this node and everything under it.
pub fn subtreeCount(self: *const Node) usize {
var n: usize = 1;
var c = self.first_child;
while (c) |child| : (c = child.next_sibling) n += child.subtreeCount();
return n;
}
};
pub const Namespace = struct {
allocator: std.mem.Allocator,
root: *Node,
pub fn init(allocator: std.mem.Allocator) !Namespace {
const root = try allocator.create(Node);
root.* = .{ .kind = .root };
return .{ .allocator = allocator, .root = root };
}
pub fn nodeCount(self: *const Namespace) usize {
return self.root.subtreeCount();
}
fn findChild(parent: *Node, segment: [4]u8) ?*Node {
var c = parent.first_child;
while (c) |child| : (c = child.next_sibling) {
if (std.mem.eql(u8, &child.segment, &segment)) return child;
}
return null;
}
/// The direct child of `node` named `segment`, or null. Unlike `resolve`, this does
/// not apply the search-rule walk-up — it looks only at immediate children (for
/// reading a device's own hardware ID (`_HID`) / current resource settings (`_CRS`)).
pub fn childOf(node: *Node, segment: [4]u8) ?*Node {
return findChild(node, segment);
}
fn newChild(self: *Namespace, parent: *Node, segment: [4]u8, kind: NodeKind) !*Node {
const n = try self.allocator.create(Node);
n.* = .{ .segment = segment, .kind = kind, .parent = parent };
// Append at the tail so a dump reads in declaration order.
if (parent.first_child == null) {
parent.first_child = n;
} else {
var current = parent.first_child.?;
while (current.next_sibling) |sib| current = sib;
current.next_sibling = n;
}
return n;
}
/// Create a Field unit node directly under `scope` (field units live in the
/// scope of the Field/IndexField/BankField, not under the region).
pub fn newFieldUnit(self: *Namespace, scope: *Node, segment: [4]u8) !*Node {
return self.findOrCreate(scope, segment, .field);
}
fn findOrCreate(self: *Namespace, parent: *Node, segment: [4]u8, kind: NodeKind) !*Node {
if (findChild(parent, segment)) |existing| {
// Reopening a scope (e.g. Scope(\_SB) after Device \_SB) keeps the more
// specific kind rather than downgrading to a plain scope.
if (existing.kind == .scope and kind != .scope) existing.kind = kind;
return existing;
}
return self.newChild(parent, segment, kind);
}
/// The node a definition's NameString names, creating any intermediate scopes.
/// The final segment is created (or found) with `kind`; intermediates are
/// scopes. Returns the namespace root for a NullName (empty path).
pub fn place(
self: *Namespace,
current: *Node,
rooted: bool,
parents: u8,
segments: []const [4]u8,
kind: NodeKind,
) !*Node {
var base = startNode(self, current, rooted, parents);
if (segments.len == 0) return base;
var i: usize = 0;
while (i + 1 < segments.len) : (i += 1) {
base = try self.findOrCreate(base, segments[i], .scope);
}
return self.findOrCreate(base, segments[segments.len - 1], kind);
}
/// Resolve a NameString *reference* to an existing node, or null. A single
/// relative segment uses the ACPI search rule (walk up the ancestors); any
/// rooted, parented, or multi-segment path is resolved exactly.
pub fn resolve(
self: *Namespace,
current: *Node,
rooted: bool,
parents: u8,
segments: []const [4]u8,
) ?*Node {
if (segments.len == 0) return null;
if (!rooted and parents == 0 and segments.len == 1) {
// Search rule: this scope, then each ancestor up to the root.
var scope: ?*Node = current;
while (scope) |s| : (scope = s.parent) {
if (findChild(s, segments[0])) |n| return n;
}
return null;
}
var base = startNode(self, current, rooted, parents);
for (segments) |segment| {
base = findChild(base, segment) orelse return null;
}
return base;
}
fn startNode(self: *Namespace, current: *Node, rooted: bool, parents: u8) *Node {
if (rooted) return self.root;
var base = current;
var up = parents;
while (up > 0) : (up -= 1) base = base.parent orelse self.root;
return base;
}
};
library/device/acpi/aml/opcodes.zig
+137
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@@ -0,0 +1,137 @@
//! AML opcode constants — the full ACPI Machine Language opcode table.
//!
//! Single-byte opcodes are plain values. Extended opcodes are a two-byte sequence
//! `ext_prefix` (0x5B) followed by a byte listed under `ext`. A few comparison
//! opcodes are `lnot_opcode` (0x92) followed by a second byte (see `lnot`).
// --- name / path characters -------------------------------------------------
pub const zero_opcode = 0x00;
pub const one_opcode = 0x01;
pub const alias_opcode = 0x06;
pub const name_opcode = 0x08;
pub const byte_prefix = 0x0A;
pub const word_prefix = 0x0B;
pub const dword_prefix = 0x0C;
pub const string_prefix = 0x0D;
pub const qword_prefix = 0x0E;
pub const scope_opcode = 0x10;
pub const buffer_opcode = 0x11;
pub const package_opcode = 0x12;
pub const var_package_opcode = 0x13;
pub const method_opcode = 0x14;
pub const external_opcode = 0x15;
pub const dual_name_prefix = 0x2E;
pub const multi_name_prefix = 0x2F;
pub const extended_opcode_prefix = 0x5B;
pub const root_char = 0x5C;
pub const parent_prefix_char = 0x5E;
pub const name_char_underscore = 0x5F;
pub const digit_char_start = 0x30;
pub const digit_char_end = 0x39;
pub const name_char_start = 0x41; // 'A'
pub const name_char_end = 0x5A; // 'Z'
// --- locals / args ----------------------------------------------------------
pub const local0_opcode = 0x60;
pub const local7_opcode = 0x67;
pub const arg0_opcode = 0x68;
pub const arg6_opcode = 0x6E;
// --- store / references / arithmetic ---------------------------------------
pub const store_opcode = 0x70;
pub const ref_of_opcode = 0x71;
pub const add_opcode = 0x72;
pub const concat_opcode = 0x73;
pub const subtract_opcode = 0x74;
pub const increment_opcode = 0x75;
pub const decrement_opcode = 0x76;
pub const multiply_opcode = 0x77;
pub const divide_opcode = 0x78;
pub const shift_left_opcode = 0x79;
pub const shift_right_opcode = 0x7A;
pub const and_opcode = 0x7B;
pub const nand_opcode = 0x7C;
pub const or_opcode = 0x7D;
pub const nor_opcode = 0x7E;
pub const xor_opcode = 0x7F;
pub const not_opcode = 0x80;
pub const find_set_left_bit_opcode = 0x81;
pub const find_set_right_bit_opcode = 0x82;
pub const dereference_of_opcode = 0x83;
pub const concat_resource_opcode = 0x84;
pub const mod_opcode = 0x85;
pub const notify_opcode = 0x86;
pub const size_of_opcode = 0x87;
pub const index_opcode = 0x88;
pub const match_opcode = 0x89;
pub const create_dword_field_opcode = 0x8A;
pub const create_word_field_opcode = 0x8B;
pub const create_byte_field_opcode = 0x8C;
pub const create_bit_field_opcode = 0x8D;
pub const object_type_opcode = 0x8E;
pub const create_qword_field_opcode = 0x8F;
pub const land_opcode = 0x90;
pub const lor_opcode = 0x91;
pub const lnot_opcode = 0x92; // may be followed by a second byte (see `lnot`)
pub const lequal_opcode = 0x93;
pub const lgreater_opcode = 0x94;
pub const lless_opcode = 0x95;
pub const to_buffer_opcode = 0x96;
pub const to_decimal_string_opcode = 0x97;
pub const to_hex_string_opcode = 0x98;
pub const to_integer_opcode = 0x99;
pub const to_string_opcode = 0x9C;
pub const copy_object_opcode = 0x9D;
pub const mid_opcode = 0x9E;
pub const continue_opcode = 0x9F;
pub const if_opcode = 0xA0;
pub const else_opcode = 0xA1;
pub const while_opcode = 0xA2;
pub const noop_opcode = 0xA3;
pub const return_opcode = 0xA4;
pub const break_opcode = 0xA5;
pub const break_point_opcode = 0xCC;
pub const ones_opcode = 0xFF;
/// Second bytes of the `lnot_opcode` (0x92) compound comparison opcodes.
pub const lnot = struct {
pub const not_equal = 0x93; // LNotEqualOp: 0x92 0x93
pub const less_equal = 0x94; // LLessEqualOp: 0x92 0x94
pub const greater_equal = 0x95; // LGreaterEqualOp: 0x92 0x95
};
/// Second bytes of extended opcodes (prefixed by `extended_opcode_prefix`, 0x5B).
pub const extended = struct {
pub const mutex = 0x01;
pub const event = 0x02;
pub const conditional_reference_of = 0x12;
pub const create_field = 0x13;
pub const load_table = 0x1F;
pub const load = 0x20;
pub const stall = 0x21;
pub const sleep = 0x22;
pub const acquire = 0x23;
pub const signal = 0x24;
pub const wait = 0x25;
pub const reset = 0x26;
pub const release = 0x27;
pub const from_bcd = 0x28;
pub const to_bcd = 0x29;
pub const unload = 0x2A;
pub const revision = 0x30;
pub const debug = 0x31;
pub const fatal = 0x32;
pub const timer = 0x33;
pub const operation_region = 0x80;
pub const field = 0x81;
pub const device = 0x82;
pub const processor = 0x83;
pub const power_resource = 0x84;
pub const thermal_zone = 0x85;
pub const index_field = 0x86;
pub const bank_field = 0x87;
pub const data_region = 0x88;
};
library/device/acpi/aml/parser.zig
+517
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//! Recursive-descent AML parser. Walks the entire byte stream — including method
//! bodies — building the ACPI namespace as it goes. It does not *evaluate*
//! anything (no OperationRegion reads, no arithmetic); it parses structure so the
//! cursor stays aligned and every named object is recorded.
//!
//! The one genuine ambiguity in AML is method invocation: a bare NameString in an
//! operand position is a call whose argument count is only known from the method's
//! (earlier) declaration. Because we build the namespace in the same in-order pass,
//! `resolve` finds that declaration and tells us how many operands to consume.
//!
//! Safety net: every object delimited by a PkgLength (Scope/Device/Method/If/While/
//! Field/Buffer/Package/…) is parsed within its known extent, and the cursor is
//! snapped to that extent afterwards. So a mis-resolved invocation can only desync
//! *within* one such object; the enclosing walk realigns at the boundary.
const std = @import("std");
const opcode = @import("opcodes.zig");
const Namespace = @import("namespace.zig").Namespace;
const Node = @import("namespace.zig").Node;
const NodeKind = @import("namespace.zig").NodeKind;
pub const Error = error{ Truncated, Malformed } || std.mem.Allocator.Error;
const maximum_segments = 64;
/// A parsed NameString: an optional root anchor or some parent hops, then a list
/// of 4-byte segments.
const NamePath = struct {
rooted: bool = false,
parents: u8 = 0,
segments: [maximum_segments][4]u8 = undefined,
count: usize = 0,
fn slice(self: *const NamePath) []const [4]u8 {
return self.segments[0..self.count];
}
};
pub const Parser = struct {
aml: []const u8,
position: usize = 0,
namespace: *Namespace,
pub fn init(aml: []const u8, namespace: *Namespace) Parser {
return .{ .aml = aml, .namespace = namespace };
}
/// Parse the whole block as a TermList under the namespace root. Returns the
/// number of bytes consumed — equal to `aml.len` for a clean full traversal.
pub fn parseAll(self: *Parser) usize {
self.termList(self.aml.len, self.namespace.root);
return self.position;
}
// --- cursor primitives --------------------------------------------------
fn eof(self: *Parser) bool {
return self.position >= self.aml.len;
}
fn peek(self: *Parser) ?u8 {
return if (self.eof()) null else self.aml[self.position];
}
fn readByte(self: *Parser) Error!u8 {
if (self.eof()) return error.Truncated;
const b = self.aml[self.position];
self.position += 1;
return b;
}
fn skip(self: *Parser, n: usize) Error!void {
if (self.position + n > self.aml.len) return error.Truncated;
self.position += n;
}
fn skipCString(self: *Parser) Error!void {
while (true) {
const b = try self.readByte();
if (b == 0) return;
}
}
/// AML PkgLength: the lead byte's top two bits give how many extra bytes
/// follow; the value counts from the start of the PkgLength field.
fn readPackageLength(self: *Parser) Error!usize {
const lead = try self.readByte();
const follow: usize = lead >> 6;
if (follow == 0) return lead & 0x3F;
var value: usize = lead & 0x0F;
var i: usize = 0;
while (i < follow) : (i += 1) {
const b = try self.readByte();
value |= @as(usize, b) << @intCast(4 + i * 8);
}
return value;
}
fn readNameSegment(self: *Parser) Error![4]u8 {
if (self.position + 4 > self.aml.len) return error.Truncated;
const segment = self.aml[self.position..][0..4].*;
self.position += 4;
return segment;
}
fn readNameString(self: *Parser) Error!NamePath {
var name_path = NamePath{};
// A NameString is either root-anchored or parent-relative, not both.
if (self.peek() == opcode.root_char) {
name_path.rooted = true;
self.position += 1;
} else {
while (self.peek() == opcode.parent_prefix_char) : (self.position += 1) name_path.parents += 1;
}
const lead = self.peek() orelse return name_path;
switch (lead) {
0x00 => self.position += 1, // NullName
opcode.dual_name_prefix => {
self.position += 1;
try self.appendSegment(&name_path);
try self.appendSegment(&name_path);
},
opcode.multi_name_prefix => {
self.position += 1;
const count = try self.readByte();
var i: usize = 0;
while (i < count) : (i += 1) try self.appendSegment(&name_path);
},
else => {
if (isNameStart(lead)) try self.appendSegment(&name_path);
},
}
return name_path;
}
fn appendSegment(self: *Parser, name_path: *NamePath) Error!void {
const segment = try self.readNameSegment();
if (name_path.count < maximum_segments) {
name_path.segments[name_path.count] = segment;
name_path.count += 1;
}
}
// --- term list / object -------------------------------------------------
/// Parse objects until `end`, then snap to `end`. Any parse error resyncs to
/// the boundary rather than propagating — containment for the rare desync.
fn termList(self: *Parser, end: usize, scope: *Node) void {
while (self.position < end) {
self.object(scope) catch break;
}
self.position = end;
}
/// Parse exactly one object/term at the cursor. Used for both TermObjs and
/// operands (TermArg / SuperName / Target all reduce to "one object" for the
/// purpose of advancing the cursor).
fn object(self: *Parser, scope: *Node) Error!void {
const lead = self.peek() orelse return error.Truncated;
if (isNameStart(lead)) return self.nameInvocation(scope);
_ = try self.readByte();
switch (lead) {
// constants and no-operand statements
opcode.zero_opcode, opcode.one_opcode, opcode.ones_opcode => {},
opcode.noop_opcode, opcode.continue_opcode, opcode.break_opcode, opcode.break_point_opcode => {},
opcode.local0_opcode...opcode.local7_opcode => {},
opcode.arg0_opcode...opcode.arg6_opcode => {},
// literal data
opcode.byte_prefix => try self.skip(1),
opcode.word_prefix => try self.skip(2),
opcode.dword_prefix => try self.skip(4),
opcode.qword_prefix => try self.skip(8),
opcode.string_prefix => try self.skipCString(),
// data containers (contents skipped via their PkgLength)
opcode.buffer_opcode, opcode.package_opcode, opcode.var_package_opcode => try self.skipPackage(),
// namespace modifiers / named objects
opcode.name_opcode => try self.parseName(scope),
opcode.alias_opcode => try self.parseAlias(scope),
opcode.scope_opcode => try self.parseScopeLike(scope, .scope),
opcode.method_opcode => try self.parseMethod(scope),
opcode.external_opcode => try self.parseExternal(scope),
opcode.extended_opcode_prefix => try self.parseExtended(scope),
// control flow
opcode.if_opcode => try self.parseIf(scope),
opcode.else_opcode => try self.parseElse(scope),
opcode.while_opcode => try self.parseWhile(scope),
opcode.return_opcode => try self.object(scope),
opcode.notify_opcode => try self.args(scope, 2),
// stores / references / unary+target
opcode.store_opcode => try self.args(scope, 2),
opcode.ref_of_opcode, opcode.dereference_of_opcode, opcode.size_of_opcode, opcode.object_type_opcode => try self.args(scope, 1),
opcode.increment_opcode, opcode.decrement_opcode => try self.args(scope, 1),
opcode.not_opcode, opcode.find_set_left_bit_opcode, opcode.find_set_right_bit_opcode => try self.args(scope, 2),
opcode.to_buffer_opcode, opcode.to_decimal_string_opcode, opcode.to_hex_string_opcode, opcode.to_integer_opcode => try self.args(scope, 2),
opcode.copy_object_opcode => try self.args(scope, 2),
// binary + target
opcode.add_opcode, opcode.subtract_opcode, opcode.multiply_opcode, opcode.mod_opcode => try self.args(scope, 3),
opcode.and_opcode, opcode.nand_opcode, opcode.or_opcode, opcode.nor_opcode, opcode.xor_opcode => try self.args(scope, 3),
opcode.shift_left_opcode, opcode.shift_right_opcode, opcode.concat_opcode, opcode.concat_resource_opcode, opcode.index_opcode => try self.args(scope, 3),
opcode.divide_opcode => try self.args(scope, 4),
opcode.to_string_opcode => try self.args(scope, 3),
opcode.mid_opcode => try self.args(scope, 4),
// logical
opcode.land_opcode, opcode.lor_opcode => try self.args(scope, 2),
opcode.lequal_opcode, opcode.lgreater_opcode, opcode.lless_opcode => try self.args(scope, 2),
opcode.lnot_opcode => try self.parseLnot(scope),
opcode.match_opcode => try self.parseMatch(scope),
// CreateXField: <source> <index> NameString
opcode.create_dword_field_opcode,
opcode.create_word_field_opcode,
opcode.create_byte_field_opcode,
opcode.create_bit_field_opcode,
opcode.create_qword_field_opcode,
=> try self.parseCreateField(scope, 2),
else => return error.Malformed,
}
}
/// Parse `n` operands.
fn args(self: *Parser, scope: *Node, n: usize) Error!void {
var i: usize = 0;
while (i < n) : (i += 1) try self.object(scope);
}
/// A NameString in operand/statement position: a method invocation (consuming
/// the callee's declared argument count) or a plain name reference.
fn nameInvocation(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
if (self.namespace.resolve(scope, name_path.rooted, name_path.parents, name_path.slice())) |node| {
if ((node.kind == .method or node.kind == .external) and node.arg_count > 0) {
try self.args(scope, node.arg_count);
}
}
}
/// Skip a PkgLength-delimited body wholesale (Buffer / Package / VarPackage):
/// the contents are pure data, never namespace declarations.
fn skipPackage(self: *Parser) Error!void {
const start = self.position;
const len = try self.readPackageLength();
const end = start + len;
if (end > self.aml.len) return error.Truncated;
self.position = end;
}
// --- namespace objects --------------------------------------------------
fn parseName(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
const value_start = self.position;
try self.object(scope); // the DataReferenceObject value
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .name);
node.value = self.aml[value_start..self.position];
}
fn parseAlias(self: *Parser, scope: *Node) Error!void {
_ = try self.readNameString(); // source
const name_path = try self.readNameString(); // the alias name
_ = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .alias);
}
fn parseMethod(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
const name_path = try self.readNameString();
const flags = try self.readByte();
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .method);
node.arg_count = flags & 0x7;
// Capture the body for on-demand evaluation and skip it — objects declared
// inside a method are created at *runtime*, not at load, so they must not
// become permanent namespace nodes.
node.value = self.aml[self.position..@min(end, self.aml.len)];
self.position = end;
}
fn parseExternal(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
_ = try self.readByte(); // object type
const arg_count = try self.readByte();
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .external);
node.arg_count = arg_count;
}
/// Scope / Device / ThermalZone: PkgLength, NameString, then a nested TermList.
fn parseScopeLike(self: *Parser, scope: *Node, kind: NodeKind) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
const name_path = try self.readNameString();
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), kind);
self.termList(end, node);
}
fn parseProcessor(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
const name_path = try self.readNameString();
try self.skip(6); // ProcID(byte) + PblkAddress(dword) + PblkLen(byte)
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .processor);
self.termList(end, node);
}
fn parsePowerResource(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
const name_path = try self.readNameString();
try self.skip(3); // SystemLevel(byte) + ResourceOrder(word)
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .power_resource);
self.termList(end, node);
}
/// OperationRegion: NameString, RegionSpace(byte), Offset(TermArg), Len(TermArg).
/// The offset/length expressions are kept as AML for lazy evaluation.
fn parseRegion(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
const space = try self.readByte();
const off_start = self.position;
try self.object(scope);
const off_end = self.position;
try self.object(scope);
const len_end = self.position;
const node = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .region);
node.region_space = space;
node.region_offset_aml = self.aml[off_start..off_end];
node.region_len_aml = self.aml[off_end..len_end];
}
fn parseDataRegion(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
try self.args(scope, 3); // signature, oem id, oem table id (TermArgs)
_ = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .region);
}
fn parseMutex(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
try self.skip(1); // sync flags
_ = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .mutex);
}
fn parseEvent(self: *Parser, scope: *Node) Error!void {
const name_path = try self.readNameString();
_ = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .event);
}
/// CreateXField: `count` TermArgs then the new field's NameString.
fn parseCreateField(self: *Parser, scope: *Node, count: usize) Error!void {
try self.args(scope, count);
const name_path = try self.readNameString();
_ = try self.namespace.place(scope, name_path.rooted, name_path.parents, name_path.slice(), .name);
}
/// Field / IndexField / BankField: a region/bank reference, flags, then a
/// FieldList whose NamedFields become nodes in the current scope. For a plain
/// Field, the first NameString is the backing region — captured so field units
/// carry a region + bit position the evaluator can read/write.
fn parseField(self: *Parser, scope: *Node, name_strings: u8, bank: bool) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
var region: ?*Node = null;
var i: u8 = 0;
while (i < name_strings) : (i += 1) {
const name_path = try self.readNameString();
// Only a plain Field's single NameString denotes an OperationRegion.
if (name_strings == 1) region = self.namespace.resolve(scope, name_path.rooted, name_path.parents, name_path.slice());
}
if (bank) try self.object(scope); // bank value TermArg
const flags = try self.readByte();
self.fieldList(end, scope, region, flags & 0x0F);
}
fn fieldList(self: *Parser, end: usize, scope: *Node, region: ?*Node, initial_access: u8) void {
var bit_offset: u32 = 0;
var access = initial_access;
while (self.position < end) {
const lead = self.peek() orelse break;
switch (lead) {
0x00 => { // ReservedField: advances the bit position
self.position += 1;
const width = self.readPackageLength() catch break;
bit_offset += @intCast(width);
},
0x01 => { // AccessField: AccessType (low nibble) + AccessAttrib
self.position += 1;
const at = self.readByte() catch break;
self.skip(1) catch break;
access = at & 0x0F;
},
0x02 => { // ConnectField: NameString | BufferData
self.position += 1;
self.object(scope) catch break;
},
0x03 => { // ExtendedAccessField: type + attrib + length
self.position += 1;
self.skip(3) catch break;
},
else => { // NamedField: NameSegment + PkgLength (bit width)
const segment = self.readNameSegment() catch break;
const width = self.readPackageLength() catch break;
const unit = self.namespace.newFieldUnit(scope, segment) catch break;
unit.region = region;
unit.bit_offset = bit_offset;
unit.bit_width = @intCast(width);
unit.access_type = access;
bit_offset += @intCast(width);
},
}
}
self.position = end;
}
// --- control flow -------------------------------------------------------
fn parseIf(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
try self.object(scope); // predicate
self.termList(end, scope);
if (self.peek() == opcode.else_opcode) {
self.position += 1;
try self.parseElse(scope);
}
}
fn parseElse(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
self.termList(end, scope);
}
fn parseWhile(self: *Parser, scope: *Node) Error!void {
const start = self.position;
const end = start + try self.readPackageLength();
try self.object(scope); // predicate
self.termList(end, scope);
}
fn parseLnot(self: *Parser, scope: *Node) Error!void {
// 0x92 followed by 0x93/94/95 is a compound comparison (two operands);
// otherwise it is a plain LNot of one operand.
const b = self.peek() orelse return error.Truncated;
switch (b) {
opcode.lnot.not_equal, opcode.lnot.less_equal, opcode.lnot.greater_equal => {
self.position += 1;
try self.args(scope, 2);
},
else => try self.object(scope),
}
}
fn parseMatch(self: *Parser, scope: *Node) Error!void {
try self.object(scope); // search package
try self.skip(1); // match opcode 1
try self.object(scope); // operand 1
try self.skip(1); // match opcode 2
try self.object(scope); // operand 2
try self.object(scope); // start index
}
// --- extended opcodes (0x5B xx) -----------------------------------------
fn parseExtended(self: *Parser, scope: *Node) Error!void {
const e = try self.readByte();
switch (e) {
opcode.extended.mutex => try self.parseMutex(scope),
opcode.extended.event => try self.parseEvent(scope),
opcode.extended.operation_region => try self.parseRegion(scope),
opcode.extended.data_region => try self.parseDataRegion(scope),
opcode.extended.field => try self.parseField(scope, 1, false),
opcode.extended.index_field => try self.parseField(scope, 2, false),
opcode.extended.bank_field => try self.parseField(scope, 2, true),
opcode.extended.device => try self.parseScopeLike(scope, .device),
opcode.extended.thermal_zone => try self.parseScopeLike(scope, .thermal_zone),
opcode.extended.processor => try self.parseProcessor(scope),
opcode.extended.power_resource => try self.parsePowerResource(scope),
opcode.extended.conditional_reference_of => try self.args(scope, 2), // SuperName, Target
opcode.extended.create_field => try self.parseCreateField(scope, 3),
opcode.extended.load_table => try self.args(scope, 6),
opcode.extended.load => try self.args(scope, 2), // NameString, Target
opcode.extended.stall, opcode.extended.sleep => try self.args(scope, 1),
opcode.extended.acquire => {
try self.object(scope); // mutex SuperName
try self.skip(2); // timeout WordData
},
opcode.extended.signal, opcode.extended.reset, opcode.extended.release, opcode.extended.unload => try self.args(scope, 1),
opcode.extended.wait => try self.args(scope, 2),
opcode.extended.from_bcd, opcode.extended.to_bcd => try self.args(scope, 2),
opcode.extended.fatal => {
try self.skip(5); // Type(byte) + Code(dword)
try self.object(scope); // Arg TermArg
},
opcode.extended.revision, opcode.extended.debug, opcode.extended.timer => {},
else => return error.Malformed,
}
}
};
fn isNameStart(b: u8) bool {
return (b >= opcode.name_char_start and b <= opcode.name_char_end) or
b == opcode.name_char_underscore or
b == opcode.root_char or
b == opcode.parent_prefix_char or
b == opcode.dual_name_prefix or
b == opcode.multi_name_prefix;
}