feat: establish bootable new architecture checkpoint

Replace the compressed boot path with a relocatable higher-half RISC-V entry, expand memory and SMP support, and add the driver, TTY, VFS, exec, signal, syscall, initramfs, and self-test infrastructure needed for a bootable kernel checkpoint.

1 files changed, 17 insertions, 0 deletions

diff --git a/na/arch/riscv/mm/tlb_md.cc b/na/arch/riscv/mm/tlb_md.cc
new file mode 100644
index 0000000..ed9aa29
--- /dev/null
+++ b/na/arch/riscv/mm/tlb_md.cc
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (C) 2026 Richard Qin */
+
+#include <arch/tlb.h>
+#include <arch/sbi.h>
+
+namespace arch::tlb {
+
+void flush_remote(uint64 cpu_mask, uint64 start, uint64 size) {
+    if (size == ~0ULL) {
+        arch::sbi::sbi_remote_sfence_vma(cpu_mask, 0, 0, ~0UL);
+    } else {
+        arch::sbi::sbi_remote_sfence_vma(cpu_mask, 0, start, size);
+    }
+}
+
+} // namespace arch::tlb