Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / arch / powerpc / include / asm / exception-64s.h
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
38 #define EX_R9           0
39 #define EX_R10          8
40 #define EX_R11          16
41 #define EX_R12          24
42 #define EX_R13          32
43 #define EX_SRR0         40
44 #define EX_DAR          48
45 #define EX_DSISR        56
46 #define EX_CCR          60
47 #define EX_R3           64
48 #define EX_LR           72
49
50 /*
51  * We're short on space and time in the exception prolog, so we can't
52  * use the normal SET_REG_IMMEDIATE macro. Normally we just need the
53  * low halfword of the address, but for Kdump we need the whole low
54  * word.
55  */
56 #define LOAD_HANDLER(reg, label)                                        \
57         addi    reg,reg,(label)-_stext; /* virt addr of handler ... */
58
59 #define EXCEPTION_PROLOG_1(area)                                \
60         mfspr   r13,SPRN_SPRG_PACA;     /* get paca address into r13 */ \
61         std     r9,area+EX_R9(r13);     /* save r9 - r12 */             \
62         std     r10,area+EX_R10(r13);                                   \
63         std     r11,area+EX_R11(r13);                                   \
64         std     r12,area+EX_R12(r13);                                   \
65         mfspr   r9,SPRN_SPRG_SCRATCH0;                                  \
66         std     r9,area+EX_R13(r13);                                    \
67         mfcr    r9
68
69 #define EXCEPTION_PROLOG_PSERIES_1(label)                               \
70         ld      r12,PACAKBASE(r13);     /* get high part of &label */   \
71         ld      r10,PACAKMSR(r13);      /* get MSR value for kernel */  \
72         mfspr   r11,SPRN_SRR0;          /* save SRR0 */                 \
73         LOAD_HANDLER(r12,label)                                         \
74         mtspr   SPRN_SRR0,r12;                                          \
75         mfspr   r12,SPRN_SRR1;          /* and SRR1 */                  \
76         mtspr   SPRN_SRR1,r10;                                          \
77         rfid;                                                           \
78         b       .       /* prevent speculative execution */
79
80 #define EXCEPTION_PROLOG_PSERIES(area, label)                           \
81         EXCEPTION_PROLOG_1(area);                                       \
82         EXCEPTION_PROLOG_PSERIES_1(label);
83
84 /*
85  * The common exception prolog is used for all except a few exceptions
86  * such as a segment miss on a kernel address.  We have to be prepared
87  * to take another exception from the point where we first touch the
88  * kernel stack onwards.
89  *
90  * On entry r13 points to the paca, r9-r13 are saved in the paca,
91  * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
92  * SRR1, and relocation is on.
93  */
94 #define EXCEPTION_PROLOG_COMMON(n, area)                                   \
95         andi.   r10,r12,MSR_PR;         /* See if coming from user      */ \
96         mr      r10,r1;                 /* Save r1                      */ \
97         subi    r1,r1,INT_FRAME_SIZE;   /* alloc frame on kernel stack  */ \
98         beq-    1f;                                                        \
99         ld      r1,PACAKSAVE(r13);      /* kernel stack to use          */ \
100 1:      cmpdi   cr1,r1,0;               /* check if r1 is in userspace  */ \
101         bge-    cr1,2f;                 /* abort if it is               */ \
102         b       3f;                                                        \
103 2:      li      r1,(n);                 /* will be reloaded later       */ \
104         sth     r1,PACA_TRAP_SAVE(r13);                                    \
105         b       bad_stack;                                                 \
106 3:      std     r9,_CCR(r1);            /* save CR in stackframe        */ \
107         std     r11,_NIP(r1);           /* save SRR0 in stackframe      */ \
108         std     r12,_MSR(r1);           /* save SRR1 in stackframe      */ \
109         std     r10,0(r1);              /* make stack chain pointer     */ \
110         std     r0,GPR0(r1);            /* save r0 in stackframe        */ \
111         std     r10,GPR1(r1);           /* save r1 in stackframe        */ \
112         ACCOUNT_CPU_USER_ENTRY(r9, r10);                                   \
113         std     r2,GPR2(r1);            /* save r2 in stackframe        */ \
114         SAVE_4GPRS(3, r1);              /* save r3 - r6 in stackframe   */ \
115         SAVE_2GPRS(7, r1);              /* save r7, r8 in stackframe    */ \
116         ld      r9,area+EX_R9(r13);     /* move r9, r10 to stackframe   */ \
117         ld      r10,area+EX_R10(r13);                                      \
118         std     r9,GPR9(r1);                                               \
119         std     r10,GPR10(r1);                                             \
120         ld      r9,area+EX_R11(r13);    /* move r11 - r13 to stackframe */ \
121         ld      r10,area+EX_R12(r13);                                      \
122         ld      r11,area+EX_R13(r13);                                      \
123         std     r9,GPR11(r1);                                              \
124         std     r10,GPR12(r1);                                             \
125         std     r11,GPR13(r1);                                             \
126         ld      r2,PACATOC(r13);        /* get kernel TOC into r2       */ \
127         mflr    r9;                     /* save LR in stackframe        */ \
128         std     r9,_LINK(r1);                                              \
129         mfctr   r10;                    /* save CTR in stackframe       */ \
130         std     r10,_CTR(r1);                                              \
131         lbz     r10,PACASOFTIRQEN(r13);                            \
132         mfspr   r11,SPRN_XER;           /* save XER in stackframe       */ \
133         std     r10,SOFTE(r1);                                             \
134         std     r11,_XER(r1);                                              \
135         li      r9,(n)+1;                                                  \
136         std     r9,_TRAP(r1);           /* set trap number              */ \
137         li      r10,0;                                                     \
138         ld      r11,exception_marker@toc(r2);                              \
139         std     r10,RESULT(r1);         /* clear regs->result           */ \
140         std     r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame      */
141
142 /*
143  * Exception vectors.
144  */
145 #define STD_EXCEPTION_PSERIES(n, label)                 \
146         . = n;                                          \
147         .globl label##_pSeries;                         \
148 label##_pSeries:                                        \
149         HMT_MEDIUM;                                     \
150         DO_KVM  n;                                      \
151         mtspr   SPRN_SPRG_SCRATCH0,r13;         /* save r13 */  \
152         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common)
153
154 #define HSTD_EXCEPTION_PSERIES(n, label)                \
155         . = n;                                          \
156         .globl label##_pSeries;                         \
157 label##_pSeries:                                        \
158         HMT_MEDIUM;                                     \
159         mtspr   SPRN_SPRG_SCRATCH0,r20; /* save r20 */  \
160         mfspr   r20,SPRN_HSRR0;         /* copy HSRR0 to SRR0 */ \
161         mtspr   SPRN_SRR0,r20;                          \
162         mfspr   r20,SPRN_HSRR1;         /* copy HSRR0 to SRR0 */ \
163         mtspr   SPRN_SRR1,r20;                          \
164         mfspr   r20,SPRN_SPRG_SCRATCH0; /* restore r20 */ \
165         mtspr   SPRN_SPRG_SCRATCH0,r13;         /* save r13 */  \
166         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common)
167
168
169 #define MASKABLE_EXCEPTION_PSERIES(n, label)                            \
170         . = n;                                                          \
171         .globl label##_pSeries;                                         \
172 label##_pSeries:                                                        \
173         HMT_MEDIUM;                                                     \
174         DO_KVM  n;                                                      \
175         mtspr   SPRN_SPRG_SCRATCH0,r13; /* save r13 */                  \
176         mfspr   r13,SPRN_SPRG_PACA;     /* get paca address into r13 */ \
177         std     r9,PACA_EXGEN+EX_R9(r13);       /* save r9, r10 */      \
178         std     r10,PACA_EXGEN+EX_R10(r13);                             \
179         lbz     r10,PACASOFTIRQEN(r13);                                 \
180         mfcr    r9;                                                     \
181         cmpwi   r10,0;                                                  \
182         beq     masked_interrupt;                                       \
183         mfspr   r10,SPRN_SPRG_SCRATCH0;                                 \
184         std     r10,PACA_EXGEN+EX_R13(r13);                             \
185         std     r11,PACA_EXGEN+EX_R11(r13);                             \
186         std     r12,PACA_EXGEN+EX_R12(r13);                             \
187         ld      r12,PACAKBASE(r13);     /* get high part of &label */   \
188         ld      r10,PACAKMSR(r13);      /* get MSR value for kernel */  \
189         mfspr   r11,SPRN_SRR0;          /* save SRR0 */                 \
190         LOAD_HANDLER(r12,label##_common)                                \
191         mtspr   SPRN_SRR0,r12;                                          \
192         mfspr   r12,SPRN_SRR1;          /* and SRR1 */                  \
193         mtspr   SPRN_SRR1,r10;                                          \
194         rfid;                                                           \
195         b       .       /* prevent speculative execution */
196
197 #ifdef CONFIG_PPC_ISERIES
198 #define DISABLE_INTS                            \
199         li      r11,0;                          \
200         stb     r11,PACASOFTIRQEN(r13);         \
201 BEGIN_FW_FTR_SECTION;                           \
202         stb     r11,PACAHARDIRQEN(r13);         \
203 END_FW_FTR_SECTION_IFCLR(FW_FEATURE_ISERIES);   \
204         TRACE_DISABLE_INTS;                     \
205 BEGIN_FW_FTR_SECTION;                           \
206         mfmsr   r10;                            \
207         ori     r10,r10,MSR_EE;                 \
208         mtmsrd  r10,1;                          \
209 END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
210 #else
211 #define DISABLE_INTS                            \
212         li      r11,0;                          \
213         stb     r11,PACASOFTIRQEN(r13);         \
214         stb     r11,PACAHARDIRQEN(r13);         \
215         TRACE_DISABLE_INTS
216 #endif /* CONFIG_PPC_ISERIES */
217
218 #define ENABLE_INTS                             \
219         ld      r12,_MSR(r1);                   \
220         mfmsr   r11;                            \
221         rlwimi  r11,r12,0,MSR_EE;               \
222         mtmsrd  r11,1
223
224 #define STD_EXCEPTION_COMMON(trap, label, hdlr)         \
225         .align  7;                                      \
226         .globl label##_common;                          \
227 label##_common:                                         \
228         EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);      \
229         DISABLE_INTS;                                   \
230         bl      .save_nvgprs;                           \
231         addi    r3,r1,STACK_FRAME_OVERHEAD;             \
232         bl      hdlr;                                   \
233         b       .ret_from_except
234
235 /*
236  * Like STD_EXCEPTION_COMMON, but for exceptions that can occur
237  * in the idle task and therefore need the special idle handling.
238  */
239 #define STD_EXCEPTION_COMMON_IDLE(trap, label, hdlr)    \
240         .align  7;                                      \
241         .globl label##_common;                          \
242 label##_common:                                         \
243         EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);      \
244         FINISH_NAP;                                     \
245         DISABLE_INTS;                                   \
246         bl      .save_nvgprs;                           \
247         addi    r3,r1,STACK_FRAME_OVERHEAD;             \
248         bl      hdlr;                                   \
249         b       .ret_from_except
250
251 #define STD_EXCEPTION_COMMON_LITE(trap, label, hdlr)    \
252         .align  7;                                      \
253         .globl label##_common;                          \
254 label##_common:                                         \
255         EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);      \
256         FINISH_NAP;                                     \
257         DISABLE_INTS;                                   \
258 BEGIN_FTR_SECTION                                       \
259         bl      .ppc64_runlatch_on;                     \
260 END_FTR_SECTION_IFSET(CPU_FTR_CTRL)                     \
261         addi    r3,r1,STACK_FRAME_OVERHEAD;             \
262         bl      hdlr;                                   \
263         b       .ret_from_except_lite
264
265 /*
266  * When the idle code in power4_idle puts the CPU into NAP mode,
267  * it has to do so in a loop, and relies on the external interrupt
268  * and decrementer interrupt entry code to get it out of the loop.
269  * It sets the _TLF_NAPPING bit in current_thread_info()->local_flags
270  * to signal that it is in the loop and needs help to get out.
271  */
272 #ifdef CONFIG_PPC_970_NAP
273 #define FINISH_NAP                              \
274 BEGIN_FTR_SECTION                               \
275         clrrdi  r11,r1,THREAD_SHIFT;            \
276         ld      r9,TI_LOCAL_FLAGS(r11);         \
277         andi.   r10,r9,_TLF_NAPPING;            \
278         bnel    power4_fixup_nap;               \
279 END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)
280 #else
281 #define FINISH_NAP
282 #endif
283
284 #endif  /* _ASM_POWERPC_EXCEPTION_H */