1 /* $Id: sh_bios.c,v 1.5 2001/01/08 08:42:32 gniibe Exp $
2  *
3  *  linux/arch/sh/kernel/sh_bios.c
4  *  C interface for trapping into the standard LinuxSH BIOS.
5  *
6  *  Copyright (C) 2000 Greg Banks, Mitch Davis
7  *
8  */
9 
10 #include <asm/sh_bios.h>
11 
12 #define BIOS_CALL_CONSOLE_WRITE     	0
13 #define BIOS_CALL_READ_BLOCK     	1
14 #define BIOS_CALL_ETH_NODE_ADDR		10
15 #define BIOS_CALL_SHUTDOWN		11
16 #define BIOS_CALL_CHAR_OUT     	    	0x1f  	/* TODO: hack */
17 #define BIOS_CALL_GDB_GET_MODE_PTR     	0xfe
18 #define BIOS_CALL_GDB_DETACH     	0xff
19 
sh_bios_call(long func,long arg0,long arg1,long arg2,long arg3)20 static __inline__ long sh_bios_call(long func, long arg0, long arg1, long arg2, long arg3)
21 {
22     register long r0 __asm__("r0") = func;
23     register long r4 __asm__("r4") = arg0;
24     register long r5 __asm__("r5") = arg1;
25     register long r6 __asm__("r6") = arg2;
26     register long r7 __asm__("r7") = arg3;
27     __asm__ __volatile__("trapa	#0x3f"
28 	 : "=z" (r0)
29 	 : "0" (r0), "r" (r4), "r" (r5), "r" (r6), "r" (r7)
30 	 : "memory");
31     return r0;
32 }
33 
34 
sh_bios_console_write(const char * buf,unsigned int len)35 void sh_bios_console_write(const char *buf, unsigned int len)
36 {
37     sh_bios_call(BIOS_CALL_CONSOLE_WRITE, (long)buf, (long)len, 0, 0);
38 }
39 
40 
sh_bios_char_out(char ch)41 void sh_bios_char_out(char ch)
42 {
43     sh_bios_call(BIOS_CALL_CHAR_OUT, ch, 0, 0, 0);
44 }
45 
46 
sh_bios_in_gdb_mode(void)47 int sh_bios_in_gdb_mode(void)
48 {
49     static char queried = 0;
50     static char *gdb_mode_p = 0;
51 
52     if (!queried)
53     {
54     	/* Query the gdb stub for address of its gdb mode variable */
55     	long r = sh_bios_call(BIOS_CALL_GDB_GET_MODE_PTR, 0, 0, 0, 0);
56 	if (r != ~0)	/* BIOS returns -1 for unknown function */
57 	    gdb_mode_p = (char *)r;
58 	queried = 1;
59     }
60     return (gdb_mode_p != 0 ? *gdb_mode_p : 0);
61 }
62 
sh_bios_gdb_detach(void)63 void sh_bios_gdb_detach(void)
64 {
65     sh_bios_call(BIOS_CALL_GDB_DETACH, 0, 0, 0, 0);
66 }
67 
sh_bios_get_node_addr(unsigned char * node_addr)68 void sh_bios_get_node_addr (unsigned char *node_addr)
69 {
70     sh_bios_call(BIOS_CALL_ETH_NODE_ADDR, 0, (long)node_addr, 0, 0);
71 }
72 
sh_bios_shutdown(unsigned int how)73 void sh_bios_shutdown(unsigned int how)
74 {
75     sh_bios_call(BIOS_CALL_SHUTDOWN, how, 0, 0, 0);
76 }
77