diff options
Diffstat (limited to 'na/arch')
| -rw-r--r-- | na/arch/riscv/include/arch/random.h | 27 | ||||
| -rw-r--r-- | na/arch/riscv/lib/random.cc | 21 |
2 files changed, 48 insertions, 0 deletions
diff --git a/na/arch/riscv/include/arch/random.h b/na/arch/riscv/include/arch/random.h new file mode 100644 index 0000000..8c8c051 --- /dev/null +++ b/na/arch/riscv/include/arch/random.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Copyright (C) 2026 Richard Qin */ + +#pragma once + +#include <lume/types.h> + +namespace arch { + +/* + * Get a random 64-bit value from the hardware TRNG. + * Returns true if supported and successful, false otherwise. + */ +bool get_hw_random(uint64& value); + +/* + * Get the current high-resolution hardware cycle counter. + * Used as an entropy fallback (Jitter/Timer). + */ +inline uint64 get_cycles() +{ + uint64 cycles; + __asm__ volatile("rdcycle %0" : "=r"(cycles)); + return cycles; +} + +} // namespace arch diff --git a/na/arch/riscv/lib/random.cc b/na/arch/riscv/lib/random.cc new file mode 100644 index 0000000..afc0078 --- /dev/null +++ b/na/arch/riscv/lib/random.cc @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Copyright (C) 2026 Richard Qin */ + +#include <arch/random.h> +#include <lume/klog.h> + +namespace arch { + +bool get_hw_random(uint64& value) +{ + /* + * Real implementation would check for Zkr extension and execute: + * csrr x, seed + * + * Since QEMU virt doesn't guarantee Zkr, we return false to + * force the MI layer to use the timer fallback. + */ + return false; +} + +} // namespace arch |
