kernel/sbi.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29

#include <fbos/compiler.h>
#include <fbos/sbi.h>

/* Implementation taken from the Linux kernel (6.12) */
__kernel struct sbi_ret __sbi_ecall(unsigned long arg0, unsigned long arg1, unsigned long arg2,
									unsigned long arg3, unsigned long arg4, unsigned long arg5,
									int fid, int ext)
{
	struct sbi_ret ret;

	register uintptr_t a0 asm("a0") = (uintptr_t)(arg0);
	register uintptr_t a1 asm("a1") = (uintptr_t)(arg1);
	register uintptr_t a2 asm("a2") = (uintptr_t)(arg2);
	register uintptr_t a3 asm("a3") = (uintptr_t)(arg3);
	register uintptr_t a4 asm("a4") = (uintptr_t)(arg4);
	register uintptr_t a5 asm("a5") = (uintptr_t)(arg5);
	register uintptr_t a6 asm("a6") = (uintptr_t)(fid);
	register uintptr_t a7 asm("a7") = (uintptr_t)(ext);

	asm volatile("ecall"
				 : "+r"(a0), "+r"(a1)
				 : "r"(a2), "r"(a3), "r"(a4), "r"(a5), "r"(a6), "r"(a7)
				 : "memory");

	ret.error = (long)a0;
	ret.value = (long)a1;

	return ret;
}