zig-wgpu/src/GpuDevice.zig
2026-05-18 16:05:42 +02:00

129 lines
3.8 KiB
Zig

const std = @import("std");
const c = @import("utils.zig").c;
const sv = @import("utils.zig").sv;
const Ctx = struct {
adapter: c.WGPUAdapter = null,
device: c.WGPUDevice = null,
};
const GpuDeviceConfig = struct {
/// VRAM limit. Default 2 GB
vram_bytes_limit: u64 = 2 * 1024 * 1024 * 1024,
power_preference: enum(c_uint) {
Undefined = 0x00000000,
LowPower = 0x00000001,
HighPerformance = 0x00000002,
Force32 = 0x7FFFFFFF,
} = .HighPerformance,
};
instance: c.WGPUInstance,
adapter: c.WGPUAdapter,
device: c.WGPUDevice,
queue: c.WGPUQueue,
limits: c.WGPULimits,
config: GpuDeviceConfig,
pub fn init(config: GpuDeviceConfig) !@This() {
const instance = c.wgpuCreateInstance(
&std.mem.zeroes(c.WGPUInstanceDescriptor),
) orelse return error.NoInstance;
errdefer c.wgpuInstanceRelease(instance);
var ctx = Ctx{};
_ = c.wgpuInstanceRequestAdapter(
instance,
&.{ .powerPreference = @intFromEnum(config.power_preference) },
.{ .callback = onAdapter, .userdata1 = &ctx },
);
c.wgpuInstanceProcessEvents(instance);
const adapter = ctx.adapter orelse return error.NoAdapter;
errdefer c.wgpuAdapterRelease(adapter);
var supported_features = std.mem.zeroes(c.WGPUSupportedFeatures);
c.wgpuAdapterGetFeatures(adapter, &supported_features);
var supported_limits = std.mem.zeroes(c.WGPULimits);
supported_limits.nextInChain = null;
if (c.wgpuAdapterGetLimits(adapter, &supported_limits) != 1) return error.FailedToGetAdapterLimits;
var has_f16 = false;
for (0..supported_features.featureCount) |i| {
if (supported_features.features[i] == c.WGPUFeatureName_ShaderF16) {
has_f16 = true;
break;
}
}
var feature_buf = [_]c.WGPUFeatureName{c.WGPUFeatureName_ShaderF16};
const required_features: []const c.WGPUFeatureName =
if (has_f16) feature_buf[0..1] else &.{};
const device_descriptor = c.WGPUDeviceDescriptor{
.nextInChain = null,
.label = sv("TensorCompilerDevice"),
.requiredFeatureCount = required_features.len,
.requiredFeatures = if (required_features.len > 0) required_features.ptr else null,
.requiredLimits = &supported_limits,
};
_ = c.wgpuAdapterRequestDevice(
adapter,
&device_descriptor,
.{ .callback = onDevice, .userdata1 = &ctx },
);
c.wgpuInstanceProcessEvents(instance);
const device = ctx.device orelse return error.NoDevice;
return .{
.instance = instance,
.adapter = adapter,
.device = device,
.queue = c.wgpuDeviceGetQueue(device),
.limits = supported_limits,
.config = config,
};
}
pub fn deinit(self: @This()) void {
c.wgpuQueueRelease(self.queue);
c.wgpuDeviceRelease(self.device);
c.wgpuAdapterRelease(self.adapter);
c.wgpuInstanceRelease(self.instance);
}
pub fn poll(self: @This()) void {
_ = c.wgpuDevicePoll(self.device, 1, null);
}
fn onAdapter(
status: c.WGPURequestAdapterStatus,
adapter: c.WGPUAdapter,
_: c.WGPUStringView,
userdata1: ?*anyopaque,
_: ?*anyopaque,
) callconv(.c) void {
if (status != c.WGPURequestAdapterStatus_Success) {
std.log.err("Adapter request failed (status={d})", .{status});
return;
}
const ctx: *Ctx = @ptrCast(@alignCast(userdata1.?));
ctx.adapter = adapter;
}
fn onDevice(
status: c.WGPURequestDeviceStatus,
device: c.WGPUDevice,
_: c.WGPUStringView,
userdata1: ?*anyopaque,
_: ?*anyopaque,
) callconv(.c) void {
if (status != c.WGPURequestDeviceStatus_Success) {
std.log.err("Device request failed (status={d})", .{status});
return;
}
const ctx: *Ctx = @ptrCast(@alignCast(userdata1.?));
ctx.device = device;
}