xref: /linux/arch/mips/include/asm/dec/prom.h (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	include/asm-mips/dec/prom.h
4  *
5  *	DECstation PROM interface.
6  *
7  *	Copyright (C) 2002, 2026  Maciej W. Rozycki
8  *
9  *	Based on arch/mips/dec/prom/prom.h by the Anonymous.
10  */
11 #ifndef _ASM_DEC_PROM_H
12 #define _ASM_DEC_PROM_H
13 
14 #include <linux/types.h>
15 
16 #include <asm/addrspace.h>
17 
18 /*
19  * PMAX/3MAX PROM entry points for DS2100/3100's and DS5000/2xx's.
20  * Many of these will work for MIPSen as well!
21  */
22 #define VEC_RESET		(u64 *)CKSEG1ADDR(0x1fc00000)
23 							/* Prom base address */
24 
25 #define PMAX_PROM_ENTRY(x)	(VEC_RESET + (x))	/* Prom jump table */
26 
27 #define PMAX_PROM_HALT		PMAX_PROM_ENTRY(2)	/* valid on MIPSen */
28 #define PMAX_PROM_AUTOBOOT	PMAX_PROM_ENTRY(5)	/* valid on MIPSen */
29 #define PMAX_PROM_OPEN		PMAX_PROM_ENTRY(6)
30 #define PMAX_PROM_READ		PMAX_PROM_ENTRY(7)
31 #define PMAX_PROM_CLOSE		PMAX_PROM_ENTRY(10)
32 #define PMAX_PROM_LSEEK		PMAX_PROM_ENTRY(11)
33 #define PMAX_PROM_GETCHAR	PMAX_PROM_ENTRY(12)
34 #define PMAX_PROM_PUTCHAR	PMAX_PROM_ENTRY(13)	/* 12 on MIPSen */
35 #define PMAX_PROM_GETS		PMAX_PROM_ENTRY(15)
36 #define PMAX_PROM_PRINTF	PMAX_PROM_ENTRY(17)
37 #define PMAX_PROM_GETENV	PMAX_PROM_ENTRY(33)	/* valid on MIPSen */
38 
39 
40 /*
41  * Magic number indicating REX PROM available on DECstation.  Found in
42  * register a2 on transfer of control to program from PROM.
43  */
44 #define REX_PROM_MAGIC		0x30464354
45 
46 /* KN04 and KN05 are REX PROMs, so only do the check for R3k systems.  */
47 static inline bool prom_is_rex(u32 magic)
48 {
49 	return !IS_ENABLED(CONFIG_CPU_R3000) || magic == REX_PROM_MAGIC;
50 }
51 
52 /*
53  * 3MIN/MAXINE PROM entry points for DS5000/1xx's, DS5000/xx's and
54  * DS5000/2x0.
55  */
56 #define REX_PROM_GETBITMAP	0x84/4	/* get mem bitmap */
57 #define REX_PROM_GETCHAR	0x24/4	/* getch() */
58 #define REX_PROM_GETENV		0x64/4	/* get env. variable */
59 #define REX_PROM_GETSYSID	0x80/4	/* get system id */
60 #define REX_PROM_GETTCINFO	0xa4/4
61 #define REX_PROM_PRINTF		0x30/4	/* printf() */
62 #define REX_PROM_SLOTADDR	0x6c/4	/* slotaddr */
63 #define REX_PROM_BOOTINIT	0x54/4	/* open() */
64 #define REX_PROM_BOOTREAD	0x58/4	/* read() */
65 #define REX_PROM_CLEARCACHE	0x7c/4
66 
67 
68 /*
69  * Used by rex_getbitmap().
70  */
71 typedef struct {
72 	int pagesize;
73 	unsigned char bitmap[];
74 } memmap;
75 
76 
77 /*
78  * Function pointers as read from a PROM's callback vector.
79  */
80 extern int (*__rex_bootinit)(void);
81 extern int (*__rex_bootread)(void);
82 extern int (*__rex_getbitmap)(memmap *);
83 extern unsigned long *(*__rex_slot_address)(int);
84 extern void *(*__rex_gettcinfo)(void);
85 extern int (*__rex_getsysid)(void);
86 extern void (*__rex_clear_cache)(void);
87 
88 extern int (*__prom_getchar)(void);
89 extern char *(*__prom_getenv)(char *);
90 extern int (*__prom_printf)(char *, ...);
91 
92 extern int (*__pmax_open)(char*, int);
93 extern int (*__pmax_lseek)(int, long, int);
94 extern int (*__pmax_read)(int, void *, int);
95 extern int (*__pmax_close)(int);
96 
97 
98 #ifdef CONFIG_64BIT
99 
100 #define O32_STK_SIZE 512
101 extern unsigned long o32_stk[];
102 
103 /* Switch the stack if outside the 32-bit address space.  */
104 static inline unsigned long *o32_get_stk(void)
105 {
106 	long fp = (long)__builtin_frame_address(0);
107 
108 	return fp != (int)fp ? o32_stk + O32_STK_SIZE : NULL;
109 }
110 
111 /*
112  * On MIPS64 we have to call PROM functions via a helper
113  * dispatcher to accommodate ABI incompatibilities.
114  */
115 #define __DEC_PROM_O32(fun, arg) fun arg __asm__(#fun); \
116 				 __asm__(#fun " = call_o32")
117 
118 int __DEC_PROM_O32(_rex_bootinit, (int (*)(void), void *));
119 int __DEC_PROM_O32(_rex_bootread, (int (*)(void), void *));
120 int __DEC_PROM_O32(_rex_getbitmap, (int (*)(memmap *), void *, memmap *));
121 unsigned long *__DEC_PROM_O32(_rex_slot_address,
122 			     (unsigned long *(*)(int), void *, int));
123 void *__DEC_PROM_O32(_rex_gettcinfo, (void *(*)(void), void *));
124 int __DEC_PROM_O32(_rex_getsysid, (int (*)(void), void *));
125 void __DEC_PROM_O32(_rex_clear_cache, (void (*)(void), void *));
126 
127 int __DEC_PROM_O32(_prom_getchar, (int (*)(void), void *));
128 char *__DEC_PROM_O32(_prom_getenv, (char *(*)(char *), void *, char *));
129 int __DEC_PROM_O32(_prom_printf, (int (*)(char *, ...), void *, char *, ...));
130 
131 
132 #define rex_bootinit()		_rex_bootinit(__rex_bootinit, NULL)
133 #define rex_bootread()		_rex_bootread(__rex_bootread, NULL)
134 #define rex_getbitmap(x)	_rex_getbitmap(__rex_getbitmap, NULL, x)
135 #define rex_slot_address(x)	_rex_slot_address(__rex_slot_address, NULL, x)
136 #define rex_gettcinfo()		_rex_gettcinfo(__rex_gettcinfo, NULL)
137 #define rex_getsysid()		_rex_getsysid(__rex_getsysid, NULL)
138 #define rex_clear_cache()	_rex_clear_cache(__rex_clear_cache, NULL)
139 
140 #define prom_getchar()		_prom_getchar(__prom_getchar, NULL)
141 #define prom_getenv(x)		_prom_getenv(__prom_getenv, NULL, x)
142 #define prom_printf(x...)	_prom_printf(__prom_printf, o32_get_stk(), x)
143 
144 #else /* !CONFIG_64BIT */
145 
146 /*
147  * On plain MIPS we just call PROM functions directly.
148  */
149 #define rex_bootinit		__rex_bootinit
150 #define rex_bootread		__rex_bootread
151 #define rex_getbitmap		__rex_getbitmap
152 #define rex_slot_address	__rex_slot_address
153 #define rex_gettcinfo		__rex_gettcinfo
154 #define rex_getsysid		__rex_getsysid
155 #define rex_clear_cache		__rex_clear_cache
156 
157 #define prom_getchar		__prom_getchar
158 #define prom_getenv		__prom_getenv
159 #define prom_printf		__prom_printf
160 
161 #define pmax_open		__pmax_open
162 #define pmax_lseek		__pmax_lseek
163 #define pmax_read		__pmax_read
164 #define pmax_close		__pmax_close
165 
166 #endif /* !CONFIG_64BIT */
167 
168 
169 extern void prom_meminit(u32);
170 extern void prom_identify_arch(u32);
171 extern void prom_init_cmdline(s32, s32 *, u32);
172 
173 extern void register_prom_console(void);
174 
175 #endif /* _ASM_DEC_PROM_H */
176