A comprehensive C interface library for OpenSBI (RISC-V Supervisor Binary Interface)
OpenSBI 的完整 C 接口库，为 RISC-V 裸机开发提供标准化的 SBI 调用接口。
SPEC Version: SBI v2.0
中文版本 | English Version
- ✅ 完整的 SBI 规范支持: 实现 SBI v2.0 规范中的所有扩展
- ✅ 类型安全: 使用结构化的返回值和错误码
- ✅ 零依赖: 纯 C 实现，无外部依赖
- ✅ 内联汇编: 高效的 ecall 实现
- ✅ 广泛兼容: 支持所有主流 SBI 实现 (OpenSBI, RustSBI, BBL 等)
- ✅ 完整文档: 详细的 API 文档和使用示例
sbi_get_spec_version()- 获取 SBI 规范版本sbi_get_impl_id()- 获取 SBI 实现 IDsbi_get_impl_version()- 获取 SBI 实现版本sbi_probe_extension()- 探测 SBI 扩展支持sbi_get_mvendorid()- 获取机器厂商 IDsbi_get_marchid()- 获取机器架构 IDsbi_get_mimpid()- 获取机器实现 ID
sbi_set_timer()- 设置定时器
sbi_send_ipi()- 发送处理器间中断
sbi_remote_fence_i()- 远程指令缓存刷新sbi_remote_sfence_vma()- 远程监管者虚拟内存刷新sbi_remote_sfence_vma_asid()- 带 ASID 的远程虚拟内存刷新sbi_remote_hfence_gvma()- 远程客户虚拟内存刷新sbi_remote_hfence_gvma_vmid()- 带 VMID 的远程客户虚拟内存刷新sbi_remote_hfence_vvma()- 远程虚拟化虚拟内存刷新sbi_remote_hfence_vvma_asid()- 带 ASID 的远程虚拟化虚拟内存刷新
sbi_hart_start()- 启动 Hartsbi_hart_stop()- 停止 Hartsbi_hart_get_status()- 获取 Hart 状态sbi_hart_suspend()- 暂停 Hart
sbi_system_reset()- 系统重置
sbi_pmu_num_counters()- 获取计数器数量sbi_pmu_counter_get_info()- 获取计数器信息sbi_pmu_counter_config_matching()- 配置计数器匹配sbi_pmu_counter_start()- 启动计数器sbi_pmu_counter_stop()- 停止计数器sbi_pmu_counter_fw_read()- 读取固件计数器
sbi_debug_console_write()- 调试控制台写入sbi_debug_console_read()- 调试控制台读取sbi_debug_console_write_byte()- 调试控制台写入字节
sbi_system_suspend()- 系统暂停
sbi_cppc_probe()- 探测 CPPC 支持sbi_cppc_read()- 读取 CPPC 寄存器sbi_cppc_read_hi()- 读取 CPPC 寄存器高位sbi_cppc_write()- 写入 CPPC 寄存器
sbi_nacl_probe_feature()- 探测嵌套加速特性sbi_nacl_set_shmem()- 设置共享内存sbi_nacl_sync_csr()- 同步 CSRsbi_nacl_sync_hfence()- 同步 HFENCEsbi_nacl_sync_sret()- 同步 SRET
sbi_sta_set_shmem()- 设置共享内存
#include "opensbi_interface.h"
int main() {
// 获取 SBI 信息
struct sbiret ret = sbi_get_spec_version();
if (ret.error == SBI_SUCCESS) {
uint32_t major = ret.value >> 24;
uint32_t minor = ret.value & 0xFFFFFF;
printf("SBI Spec Version: %d.%d\n", major, minor);
}
// 获取实现信息
ret = sbi_get_impl_id();
if (ret.error == SBI_SUCCESS) {
printf("SBI Implementation: %s\n", SBI_IMPL_ID_NAMES[ret.value]);
}
// 探测扩展支持
ret = sbi_probe_extension(SBI_EXT_TIME);
if (ret.error == SBI_SUCCESS && ret.value == 1) {
printf("Timer extension is supported\n");
}
return 0;
}#include "opensbi_interface.h"
void setup_timer() {
// 设置 1 秒后的定时器中断
uint64_t current_time;
asm volatile("rdtime %0" : "=r"(current_time));
struct sbiret ret = sbi_set_timer(current_time + 10000000); // 假设 10MHz 频率
if (ret.error == SBI_SUCCESS) {
printf("Timer set successfully\n");
}
}#include "opensbi_interface.h"
void send_ipi_to_hart(unsigned long hart_id) {
unsigned long hart_mask = 1UL << hart_id;
struct sbiret ret = sbi_send_ipi(hart_mask, 0);
if (ret.error == SBI_SUCCESS) {
printf("IPI sent to hart %lu\n", hart_id);
}
}#include "opensbi_interface.h"
void start_secondary_hart(unsigned long hart_id, unsigned long start_addr) {
struct sbiret ret = sbi_hart_start(hart_id, start_addr, 0);
switch (ret.error) {
case SBI_SUCCESS:
printf("Hart %lu started successfully\n", hart_id);
break;
case SBI_ERR_INVALID_PARAM:
printf("Invalid hart ID or start address\n");
break;
case SBI_ERR_ALREADY_AVAILABLE:
printf("Hart %lu is already running\n", hart_id);
break;
default:
printf("Failed to start hart %lu: %ld\n", hart_id, ret.error);
}
}#include "opensbi_interface.h"
void debug_print(const char* str) {
while (*str) {
sbi_debug_console_write_byte(*str);
str++;
}
}
void debug_print_string(const char* str) {
int len = strlen(str);
unsigned long addr = (unsigned long)str;
struct sbiret ret = sbi_debug_console_write(len,
addr & 0xFFFFFFFF,
addr >> 32);
if (ret.error != SBI_SUCCESS) {
// 回退到字节写入
debug_print(str);
}
}#include "opensbi_interface.h"
void system_shutdown() {
struct sbiret ret = sbi_system_reset(SRST_RESET_TYPE_SHUTDOWN,
SRST_RESET_REASON_NONE);
// 此函数不应返回
}
void system_reboot() {
struct sbiret ret = sbi_system_reset(SRST_RESET_TYPE_COLD_REBOOT,
SRST_RESET_REASON_NONE);
// 此函数不应返回
}库定义了标准的 SBI 错误码：
enum {
SBI_SUCCESS = 0, // 成功
SBI_ERR_FAILED = -1, // 失败
SBI_ERR_NOT_SUPPORTED = -2, // 不支持
SBI_ERR_INVALID_PARAM = -3, // 无效参数
SBI_ERR_DENIED = -4, // 拒绝访问
SBI_ERR_INVALID_ADDRESS = -5, // 无效地址
SBI_ERR_ALREADY_AVAILABLE = -6, // 已经可用
SBI_ERR_ALREADY_STARTED = -7, // 已经启动
SBI_ERR_ALREADY_STOPPED = -8, // 已经停止
SBI_ERR_NO_SHMEM = -9, // 无共享内存
};库支持以下 SBI 实现：
- OpenSBI (推荐)
- RustSBI
- Berkeley Boot Loader (BBL)
- Xvisor
- KVM
- Diosix
- Coffer
- Xen Project
- PolarFire Hart Software Services
add_subdirectory(path/to/opensbi_interface)
target_link_libraries(your_target opensbi_interface)# 编译静态库
gcc -c src/opensbi_interface.c -I src/include -o opensbi_interface.o
ar rcs libopensbi_interface.a opensbi_interface.o
# 链接到你的项目
gcc your_main.c -L. -lopensbi_interface -I src/include -o your_programopensbi_interface/
├── src/
│ ├── include/
│ │ └── opensbi_interface.h # 主头文件
│ ├── opensbi_interface.c # 实现文件
│ └── CMakeLists.txt
├── test/
│ ├── main.c # 测试示例
│ ├── boot.S # 启动汇编
│ ├── link.ld # 链接脚本
│ └── fw_jump.elf # OpenSBI 固件
├── CMakeLists.txt
└── README.md
项目包含完整的测试示例：
# 构建测试
mkdir build && cd build
cmake ..
make
# 在 QEMU 中运行测试
qemu-system-riscv64 -machine virt -cpu rv64 -smp 4 \
-bios test/fw_jump.elf -kernel test/opensbi_test \
-nographic -serial mon:stdio所有 SBI 调用都通过 ecall 指令实现：
static struct sbiret ecall(unsigned long arg0, unsigned long arg1,
unsigned long arg2, unsigned long arg3,
unsigned long arg4, unsigned long arg5,
unsigned long fid, unsigned long eid) {
struct sbiret ret;
register uintptr_t a0 __asm__("a0") = (uintptr_t)(arg0);
register uintptr_t a1 __asm__("a1") = (uintptr_t)(arg1);
// ... 更多寄存器设置
register uintptr_t a7 __asm__("a7") = (uintptr_t)(eid);
__asm__("ecall"
: "+r"(a0), "+r"(a1)
: "r"(a2), "r"(a3), "r"(a4), "r"(a5), "r"(a6), "r"(a7)
: "memory");
ret.error = a0;
ret.value = a1;
return ret;
}struct sbiret {
long error; // 错误码
long value; // 返回值
};- RISC-V 架构: RV32, RV64
- 特权级别: 监管者模式 (S-mode)
- 编译器: GCC, Clang
- SBI 版本: v0.1 (Legacy), v0.2+, v2.0
MIT License
欢迎提交 Issue 和 Pull Request！