loader: initial loader code

src/kern/entry.zig

@@ -0,0 +1,16 @@
+const std = @import("std");
+
+const r = @import("root");
+
+const pl = r.pl;
+const ke = r.ke;
+const ki = ke.private;
+
+pub const std_options = r.std_options;
+pub const panic = r.panic;
+
+export fn kmain(info: *r.BootInfo) callconv(.c) void {
+    ke.ncpus = 1;
+
+    ki.init(info);
+}

src/kern/init.zig

@@ -9,7 +9,7 @@ const ex = r.ex;
 var thread0: ke.Thread = undefined;
 var stack: [r.kib(16)]u8 align(16) = undefined;
 
-pub fn init(boot_info: *pl.BootInfo) linksection(r.init) void {
+pub fn init(boot_info: *r.BootInfo) linksection(r.init) void {
     ki.impl.early_init();
     ki.tunable.init(boot_info);
     std.log.info("Welcome to the machine", .{});

src/kern/tunable.zig

@@ -42,7 +42,7 @@ pub fn Tunable(comptime T: type, comptime default: T, comptime name: []const u8)
     };
 }
 
-pub fn init(boot_info: *pl.BootInfo) void {
+pub fn init(boot_info: *r.BootInfo) void {
     const cmdline = boot_info.cmdline orelse return;
 
     const elems = set.elems();