1 #ifndef _ASM_POWERPC_EXCEPTION_H
2 #define _ASM_POWERPC_EXCEPTION_H
3 /*
4  * Extracted from head_64.S
5  *
6  *  PowerPC version
7  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
8  *
9  *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
10  *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
11  *  Adapted for Power Macintosh by Paul Mackerras.
12  *  Low-level exception handlers and MMU support
13  *  rewritten by Paul Mackerras.
14  *    Copyright (C) 1996 Paul Mackerras.
15  *
16  *  Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
17  *    Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
18  *
19  *  This file contains the low-level support and setup for the
20  *  PowerPC-64 platform, including trap and interrupt dispatch.
21  *
22  *  This program is free software; you can redistribute it and/or
23  *  modify it under the terms of the GNU General Public License
24  *  as published by the Free Software Foundation; either version
25  *  2 of the License, or (at your option) any later version.
26  */
27 /*
28  * The following macros define the code that appears as
29  * the prologue to each of the exception handlers.  They
30  * are split into two parts to allow a single kernel binary
31  * to be used for pSeries and iSeries.
32  *
33  * We make as much of the exception code common between native
34  * exception handlers (including pSeries LPAR) and iSeries LPAR
35  * implementations as possible.
36  */
37 #include <asm/feature-fixups.h>
38 
39 /* PACA save area size in u64 units (exgen, exmc, etc) */
40 #if defined(CONFIG_RELOCATABLE)
41 #define EX_SIZE		10
42 #else
43 #define EX_SIZE		9
44 #endif
45 
46 /*
47  * maximum recursive depth of MCE exceptions
48  */
49 #define MAX_MCE_DEPTH	4
50 
51 #ifdef __ASSEMBLY__
52 
53 #define STF_ENTRY_BARRIER_SLOT						\
54 	STF_ENTRY_BARRIER_FIXUP_SECTION;				\
55 	nop;								\
56 	nop;								\
57 	nop
58 
59 #define STF_EXIT_BARRIER_SLOT						\
60 	STF_EXIT_BARRIER_FIXUP_SECTION;					\
61 	nop;								\
62 	nop;								\
63 	nop;								\
64 	nop;								\
65 	nop;								\
66 	nop
67 
68 /*
69  * r10 must be free to use, r13 must be paca
70  */
71 #define INTERRUPT_TO_KERNEL						\
72 	STF_ENTRY_BARRIER_SLOT
73 
74 /*
75  * Macros for annotating the expected destination of (h)rfid
76  *
77  * The nop instructions allow us to insert one or more instructions to flush the
78  * L1-D cache when returning to userspace or a guest.
79  */
80 #define RFI_FLUSH_SLOT							\
81 	RFI_FLUSH_FIXUP_SECTION;					\
82 	nop;								\
83 	nop;								\
84 	nop
85 
86 #define RFI_TO_KERNEL							\
87 	rfid
88 
89 #define RFI_TO_USER							\
90 	STF_EXIT_BARRIER_SLOT;						\
91 	RFI_FLUSH_SLOT;							\
92 	rfid;								\
93 	b	rfi_flush_fallback
94 
95 #define RFI_TO_USER_OR_KERNEL						\
96 	STF_EXIT_BARRIER_SLOT;						\
97 	RFI_FLUSH_SLOT;							\
98 	rfid;								\
99 	b	rfi_flush_fallback
100 
101 #define RFI_TO_GUEST							\
102 	STF_EXIT_BARRIER_SLOT;						\
103 	RFI_FLUSH_SLOT;							\
104 	rfid;								\
105 	b	rfi_flush_fallback
106 
107 #define HRFI_TO_KERNEL							\
108 	hrfid
109 
110 #define HRFI_TO_USER							\
111 	STF_EXIT_BARRIER_SLOT;						\
112 	RFI_FLUSH_SLOT;							\
113 	hrfid;								\
114 	b	hrfi_flush_fallback
115 
116 #define HRFI_TO_USER_OR_KERNEL						\
117 	STF_EXIT_BARRIER_SLOT;						\
118 	RFI_FLUSH_SLOT;							\
119 	hrfid;								\
120 	b	hrfi_flush_fallback
121 
122 #define HRFI_TO_GUEST							\
123 	STF_EXIT_BARRIER_SLOT;						\
124 	RFI_FLUSH_SLOT;							\
125 	hrfid;								\
126 	b	hrfi_flush_fallback
127 
128 #define HRFI_TO_UNKNOWN							\
129 	STF_EXIT_BARRIER_SLOT;						\
130 	RFI_FLUSH_SLOT;							\
131 	hrfid;								\
132 	b	hrfi_flush_fallback
133 
134 #endif /* __ASSEMBLY__ */
135 
136 #endif	/* _ASM_POWERPC_EXCEPTION_H */
137