sbi_interface.h

#ifndef SBI_INTERFACE_H
#define SBI_INTERFACE_H

//--------------------------------------------------------------------
// SYSCALLs
//--------------------------------------------------------------------
#define SBI_SET_TIMER 0
#define SBI_CONSOLE_PUTCHAR 1
#define SBI_CONSOLE_GETCHAR 2
#define SBI_CLEAR_IPI 3
#define SBI_SEND_IPI 4
#define SBI_REMOTE_FENCE_I 5
#define SBI_REMOTE_SFENCE_VMA 6
#define SBI_REMOTE_SFENCE_VMA_ASID 7
#define SBI_SHUTDOWN 8

#define SBI_ECALL(__num, __a0, __a1, __a2)                                    \
	({                                                                    \
		register unsigned long a0 asm("a0") = (unsigned long)(__a0);  \
		register unsigned long a1 asm("a1") = (unsigned long)(__a1);  \
		register unsigned long a2 asm("a2") = (unsigned long)(__a2);  \
		register unsigned long a7 asm("a7") = (unsigned long)(__num); \
		asm volatile("ecall"                                          \
			     : "+r"(a0)                                       \
			     : "r"(a1), "r"(a2), "r"(a7)                      \
			     : "memory");                                     \
		a0;                                                           \
	})

#define SBI_ECALL_0(__num) SBI_ECALL(__num, 0, 0, 0)
#define SBI_ECALL_1(__num, __a0) SBI_ECALL(__num, __a0, 0, 0)
#define SBI_ECALL_2(__num, __a0, __a1) SBI_ECALL(__num, __a0, __a1, 0)

#define sbi_putchar(c) SBI_ECALL_1(SBI_CONSOLE_PUTCHAR, (c))
#define sbi_shutdown() SBI_ECALL_0(SBI_SHUTDOWN)

#endif