xtensa: ISS: fix __simc implementation

Do not rely on compiler implicitly placing function arguments into
specifc registers, place them explicitly.

Move __simc and related helpers to platform/simcall.h

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

1 files changed, 53 insertions, 0 deletions

diff --git a/arch/xtensa/platforms/iss/include/platform/simcall.h b/arch/xtensa/platforms/iss/include/platform/simcall.h
index b7952c06a2b7..8c43bfea05e1 100644
--- a/arch/xtensa/platforms/iss/include/platform/simcall.h
+++ b/arch/xtensa/platforms/iss/include/platform/simcall.h
@@ -57,6 +57,59 @@
 #define  XTISS_SELECT_ONE_WRITE   2
 #define  XTISS_SELECT_ONE_EXCEPT  3
 
+static int errno;
+
+static inline int __simc(int a, int b, int c, int d, int e, int f)
+{
+	int ret;
+	register int a1 asm("a2") = a;
+	register int b1 asm("a3") = b;
+	register int c1 asm("a4") = c;
+	register int d1 asm("a5") = d;
+	register int e1 asm("a6") = e;
+	register int f1 asm("a7") = f;
+	__asm__ __volatile__ (
+			"simcall\n"
+			"mov %0, a2\n"
+			"mov %1, a3\n"
+			: "=a" (ret), "=a" (errno), "+r"(a1), "+r"(b1)
+			: "r"(c1), "r"(d1), "r"(e1), "r"(f1)
+			: );
+	return ret;
+}
+
+static inline int simc_open(char *file, int flags, int mode)
+{
+	return __simc(SYS_open, (int) file, flags, mode, 0, 0);
+}
+
+static inline int simc_close(int fd)
+{
+	return __simc(SYS_close, fd, 0, 0, 0, 0);
+}
+
+static inline int simc_ioctl(int fd, int request, void *arg)
+{
+	return __simc(SYS_ioctl, fd, request, (int) arg, 0, 0);
+}
+
+static inline int simc_read(int fd, void *buf, size_t count)
+{
+	return __simc(SYS_read, fd, (int) buf, count, 0, 0);
+}
+
+static inline int simc_write(int fd, void *buf, size_t count)
+{
+	return __simc(SYS_write, fd, (int) buf, count, 0, 0);
+}
+
+static inline int simc_poll(int fd)
+{
+	struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
+
+	return __simc(SYS_select_one, fd, XTISS_SELECT_ONE_READ, (int)&tv,
+			0, 0);
+}
 
 #endif /* _XTENSA_PLATFORM_ISS_SIMCALL_H */