1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1996, 1997, 1998, 1999, 2000 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 *
9 * Protected memory access.  Used for everything that might take revenge
10 * by sending a DBE error like accessing possibly non-existant memory or
11 * devices.
12 */
13#ifndef _ASM_PACCESS_H
14#define _ASM_PACCESS_H
15
16#include <linux/errno.h>
17
18#define put_dbe(x,ptr) __put_dbe((x),(ptr),sizeof(*(ptr)))
19#define get_dbe(x,ptr) __get_dbe((x),(ptr),sizeof(*(ptr)))
20
21struct __large_pstruct { unsigned long buf[100]; };
22#define __mp(x) (*(struct __large_pstruct *)(x))
23
24#define __get_dbe(x,ptr,size) ({ \
25int __gu_err; \
26__typeof(*(ptr)) __gu_val; \
27unsigned long __gu_addr; \
28__asm__("":"=r" (__gu_val)); \
29__gu_addr = (unsigned long) (ptr); \
30__asm__("":"=r" (__gu_err)); \
31switch (size) { \
32case 1: __get_dbe_asm("lb"); break; \
33case 2: __get_dbe_asm("lh"); break; \
34case 4: __get_dbe_asm("lw"); break; \
35case 8:  __get_dbe_asm("ld"); break; \
36default: __get_dbe_unknown(); break; \
37} x = (__typeof__(*(ptr))) __gu_val; __gu_err; })
38
39#define __get_dbe_asm(insn) \
40({ \
41__asm__ __volatile__( \
42	".set\tpush\n\t" \
43	".set\tnoreorder\n\t" \
44	insn "\t%1,%2\n\t" \
45	"1:\tmove\t%0,$0\n" \
46	".set\tpop\n\t" \
47	"2:\n\t" \
48	".section\t.fixup,\"ax\"\n" \
49	"3:\tli\t%0,%3\n\t" \
50	"move\t%1,$0\n\t" \
51	"j\t2b\n\t" \
52	".previous\n\t" \
53	".section\t__dbe_table,\"a\"\n\t" \
54	".word\t1b-4,3b\n\t" \
55	".previous" \
56	:"=r" (__gu_err), "=r" (__gu_val) \
57	:"o" (__mp(__gu_addr)), "i" (-EFAULT)); })
58
59extern void __get_dbe_unknown(void);
60
61#define __put_dbe(x,ptr,size) ({ \
62int __pu_err; \
63__typeof__(*(ptr)) __pu_val; \
64unsigned long __pu_addr; \
65__pu_val = (x); \
66__pu_addr = (unsigned long) (ptr); \
67__asm__("":"=r" (__pu_err)); \
68switch (size) { \
69case 1: __put_dbe_asm("sb"); break; \
70case 2: __put_dbe_asm("sh"); break; \
71case 4: __put_dbe_asm("sw"); break; \
72case 8: __put_dbe_asm("sd"); break; \
73default: __put_dbe_unknown(); break; \
74} __pu_err; })
75
76#define __put_dbe_asm(insn) \
77({ \
78__asm__ __volatile__( \
79	".set\tpush\n\t" \
80	".set\tnoreorder\n\t" \
81	insn "\t%1,%2\n\t" \
82	"1:\tmove\t%0,$0\n" \
83	".set\tpop\n\t" \
84	"2:\n\t" \
85	".section\t.fixup,\"ax\"\n" \
86	"3:\tli\t%0,%3\n\t" \
87	"j\t2b\n\t" \
88	".previous\n\t" \
89	".section\t__dbe_table,\"a\"\n\t" \
90	".word\t1b-4,3b\n\t" \
91	".previous" \
92	:"=r" (__pu_err) \
93	:"r" (__pu_val), "o" (__mp(__pu_addr)), "i" (-EFAULT)); })
94
95extern void __put_dbe_unknown(void);
96
97#endif /* _ASM_PACCESS_H */
98