| /* Copyright 2018 SiFive, Inc */ |
| /* SPDX-License-Identifier: Apache-2.0 */ |
| |
| #ifndef METAL__IO_H |
| #define METAL__IO_H |
| |
| /* This macro enforces that the compiler will not elide the given access. */ |
| #define __METAL_ACCESS_ONCE(x) (*(__typeof__(*x) volatile *)(x)) |
| |
| /* Allows users to specify arbitrary fences. */ |
| #define __METAL_IO_FENCE(pred, succ) __asm__ volatile ("fence " #pred "," #succ ::: "memory"); |
| |
| /* Types that explicitly describe an address as being used for memory-mapped |
| * IO. These should only be accessed via __METAL_ACCESS_ONCE. */ |
| typedef unsigned char __metal_io_u8; |
| typedef unsigned short __metal_io_u16; |
| typedef unsigned int __metal_io_u32; |
| #if __riscv_xlen >= 64 |
| typedef unsigned long __metal_io_u64; |
| #endif |
| |
| #endif |
