Cross-architecture test suite

src/main.zig

@@ -3,6 +3,8 @@ const danos = @import("danos");
 const arch = @import("arch");
 const console = @import("console.zig");
 const pmm = @import("pmm.zig");
+const tests = @import("tests.zig");
+const build_options = @import("build_options");
 const BootInfo = danos.BootInfo;
 
 /// The calling convention used to enter the kernel. Pinned to SysV explicitly:
@@ -25,6 +27,8 @@ export fn _start(boot_info: *const BootInfo) callconv(kernel_abi) noreturn {
 }
 
 fn kmain(boot_info: *const BootInfo) noreturn {
+    arch.serialInit(); // machine-readable log; console mirrors to it
+
     const fb = boot_info.framebuffer;
     con = console.Console.init(fb);
     con.clear();
@@ -87,6 +91,13 @@ fn kmain(boot_info: *const BootInfo) noreturn {
     con.print("\ndanos: paging enabled\n", .{});
     con.print("  page tables: CR3 = 0x{x:0>16}\n", .{arch.readCr3()});
 
+    // In a test build (`zig build -Dtest-case=<name>`), run that case and stop.
+    // Normal builds fall through to the idle halt.
+    if (build_options.test_case) |case| {
+        tests.run(case, boot_info);
+        arch.halt();
+    }
+
     con.write("\nkernel initialised; nothing left to do, halting.\n");
 
     arch.halt();