feat(kernel): SystemControl cap for halt, board device table + boot caps to init, RegionAddress syscall, idle loop services irqs

crates/adapter-riscv/src/main.rs

@@ -17,6 +17,12 @@ use kernel_cell::KernelCell;
 
 static KERNEL: KernelCell<kernel::Kernel<platform::RiscVPlatform>> = KernelCell::uninit();
 
+fn kern_mut() -> &'static mut kernel::Kernel<platform::RiscVPlatform> {
+    // SAFETY: single core; boot code runs before any trap can touch the
+    // kernel.
+    unsafe { &mut *kernel_ptr() }
+}
+
 pub fn kernel_ptr() -> *mut kernel::Kernel<platform::RiscVPlatform> {
     KERNEL.as_ptr()
 }
@@ -51,10 +57,18 @@ extern "C" fn kmain() -> ! {
     let input = boot::loader::load_server(&uart, &mut blk, b"input.elf", "input");
     let virtio_base = blk.base();
 
+    let board = board::devices().unwrap_or_else(|| halt(&uart, "bad board table"));
+    kern_mut()
+        .register_board(init.pid, &board)
+        .unwrap_or_else(|_| halt(&uart, "board registration failed"));
     devices::storage_setup::configure(&uart, init.pid, storage.pid, virtio_base);
     devices::gpu_setup::configure(&uart, display.pid);
     devices::input_setup::configure(&uart, input.pid);
     boot::caps::grant_all(&uart, init.pid, storage.pid, display.pid, input.pid);
+    // After grant_all, so the slots init already relies on stay put.
+    kern_mut()
+        .grant_boot_authority(init.pid, &board)
+        .unwrap_or_else(|_| halt(&uart, "boot authority failed"));
 
     uart.write_str("k-os: entering userspace\n");
     boot::loader::enter_userspace(init.pid, init.entry, SHARED_BUF_VA);