pluto/src/kernel/kmain.zig
2022-03-06 15:22:34 +00:00

198 lines
7.8 KiB
Zig

const std = @import("std");
const kmain_log = std.log.scoped(.kmain);
const builtin = @import("builtin");
const is_test = builtin.is_test;
const build_options = @import("build_options");
const arch = @import("arch.zig").internals;
const tty = @import("tty.zig");
const log_root = @import("log.zig");
const pmm = @import("pmm.zig");
const serial = @import("serial.zig");
const vmm = @import("vmm.zig");
const mem = @import("mem.zig");
const panic_root = @import("panic.zig");
const task = @import("task.zig");
const heap = @import("heap.zig");
const scheduler = @import("scheduler.zig");
const vfs = @import("filesystem/vfs.zig");
const initrd = @import("filesystem/initrd.zig");
const keyboard = @import("keyboard.zig");
const Allocator = std.mem.Allocator;
comptime {
if (!is_test) {
switch (builtin.cpu.arch) {
.i386 => _ = @import("arch/x86/boot.zig"),
else => unreachable,
}
}
}
// This is for unit testing as we need to export KERNEL_ADDR_OFFSET as it is no longer available
// from the linker script
// These will need to be kept up to date with the debug logs in the mem init.
export var KERNEL_ADDR_OFFSET: u32 = if (builtin.is_test) 0xC0000000 else undefined;
export var KERNEL_STACK_START: u32 = if (builtin.is_test) 0xC014A000 else undefined;
export var KERNEL_STACK_END: u32 = if (builtin.is_test) 0xC014E000 else undefined;
export var KERNEL_VADDR_START: u32 = if (builtin.is_test) 0xC0100000 else undefined;
export var KERNEL_VADDR_END: u32 = if (builtin.is_test) 0xC014E000 else undefined;
export var KERNEL_PHYSADDR_START: u32 = if (builtin.is_test) 0x100000 else undefined;
export var KERNEL_PHYSADDR_END: u32 = if (builtin.is_test) 0x14E000 else undefined;
// Just call the panic function, as this need to be in the root source file
pub fn panic(msg: []const u8, error_return_trace: ?*std.builtin.StackTrace) noreturn {
@setCold(true);
panic_root.panic(error_return_trace, "{s}", .{msg});
}
pub const log_level: std.log.Level = .debug;
// Define root.log to override the std implementation
pub fn log(
comptime level: std.log.Level,
comptime scope: @TypeOf(.EnumLiteral),
comptime format: []const u8,
args: anytype,
) void {
log_root.log(level, "(" ++ @tagName(scope) ++ "): " ++ format, args);
}
var kernel_heap: heap.FreeListAllocator = undefined;
export fn kmain(boot_payload: arch.BootPayload) void {
const serial_stream = serial.init(boot_payload);
log_root.init(serial_stream);
const mem_profile = arch.initMem(boot_payload) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise memory profile: {}", .{e});
};
var fixed_allocator = mem_profile.fixed_allocator;
pmm.init(&mem_profile, fixed_allocator.allocator());
var kernel_vmm = vmm.init(&mem_profile, fixed_allocator.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise kernel VMM: {}", .{e});
};
kmain_log.info("Init arch " ++ @tagName(builtin.cpu.arch) ++ "\n", .{});
arch.init(&mem_profile);
kmain_log.info("Arch init done\n", .{});
panic_root.initSymbols(&mem_profile, fixed_allocator.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise panic symbols: {}\n", .{e});
};
// The VMM runtime tests can't happen until the architecture has initialised itself
switch (build_options.test_mode) {
.Initialisation => vmm.runtimeTests(arch.VmmPayload, kernel_vmm, &mem_profile),
else => {},
}
// Give the kernel heap 10% of the available memory. This can be fine-tuned as time goes on.
var heap_size = mem_profile.mem_kb / 10 * 1024;
// The heap size must be a power of two so find the power of two smaller than or equal to the heap_size
if (!std.math.isPowerOfTwo(heap_size)) {
heap_size = std.math.floorPowerOfTwo(usize, heap_size);
}
kernel_heap = heap.init(arch.VmmPayload, kernel_vmm, vmm.Attributes{ .kernel = true, .writable = true, .cachable = true }, heap_size) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise kernel heap: {}\n", .{e});
};
tty.init(kernel_heap.allocator(), boot_payload);
var arch_kb = keyboard.init(fixed_allocator.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to inititalise keyboard: {}\n", .{e});
};
if (arch_kb) |kb| {
keyboard.addKeyboard(kb) catch |e| panic_root.panic(@errorReturnTrace(), "Failed to add architecture keyboard: {}\n", .{e});
}
// Get the ramdisk module
const rd_module = for (mem_profile.modules) |module| {
if (std.mem.eql(u8, module.name, "initrd.ramdisk")) {
break module;
}
} else null;
if (rd_module) |module| {
// Load the ram disk
const rd_len: usize = module.region.end - module.region.start;
const ramdisk_bytes = @intToPtr([*]u8, module.region.start)[0..rd_len];
var initrd_stream = std.io.fixedBufferStream(ramdisk_bytes);
var ramdisk_filesystem = initrd.InitrdFS.init(&initrd_stream, kernel_heap.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise ramdisk: {}\n", .{e});
};
// Can now free the module as new memory is allocated for the ramdisk filesystem
kernel_vmm.free(module.region.start) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to free ramdisk: {}\n", .{e});
};
// Need to init the vfs after the ramdisk as we need the root node from the ramdisk filesystem
vfs.setRoot(ramdisk_filesystem.root_node) catch |e| {
panic_root.panic(@errorReturnTrace(), "Ramdisk root node isn't a directory node: {}\n", .{e});
};
}
scheduler.init(kernel_heap.allocator(), &mem_profile) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to initialise scheduler: {}\n", .{e});
};
// Initialisation is finished, now does other stuff
kmain_log.info("Init\n", .{});
// Main initialisation finished so can enable interrupts
arch.enableInterrupts();
kmain_log.info("Creating init2\n", .{});
// Create a init2 task
var stage2_task = task.Task.create(@ptrToInt(initStage2), true, kernel_vmm, kernel_heap.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to create init stage 2 task: {}\n", .{e});
};
scheduler.scheduleTask(stage2_task, kernel_heap.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Failed to schedule init stage 2 task: {}\n", .{e});
};
// Can't return for now, later this can return maybe
// TODO: Maybe make this the idle task
arch.spinWait();
}
///
/// Stage 2 initialisation. This will initialise main kernel features after the architecture
/// initialisation.
///
fn initStage2() noreturn {
tty.clear();
const logo =
\\ _____ _ _ _ _______ ____
\\ | __ \ | | | | | | |__ __| / __ \
\\ | |__) | | | | | | | | | | | | |
\\ | ___/ | | | | | | | | | | | |
\\ | | | |____ | |__| | | | | |__| |
\\ |_| |______| \____/ |_| \____/
;
tty.print("{s}\n\n", .{logo});
tty.print("Hello Pluto from kernel :)\n", .{});
const devices = arch.getDevices(kernel_heap.allocator()) catch |e| {
panic_root.panic(@errorReturnTrace(), "Unable to get device list: {}\n", .{e});
};
for (devices) |device| {
device.print();
}
switch (build_options.test_mode) {
.Initialisation => {
kmain_log.info("SUCCESS\n", .{});
},
else => {},
}
// Can't return for now, later this can return maybe
arch.spinWait();
}
test "" {
_ = @import("filesystem/fat32.zig");
}