c9ac8bada786f19888bab6b93536054da44f599f
[linux-2.6.git] / arch / ia64 / kernel / minstate.h
1
2 #include <asm/cache.h>
3
4 #include "entry.h"
5
6 /*
7  * DO_SAVE_MIN switches to the kernel stacks (if necessary) and saves
8  * the minimum state necessary that allows us to turn psr.ic back
9  * on.
10  *
11  * Assumed state upon entry:
12  *      psr.ic: off
13  *      r31:    contains saved predicates (pr)
14  *
15  * Upon exit, the state is as follows:
16  *      psr.ic: off
17  *       r2 = points to &pt_regs.r16
18  *       r8 = contents of ar.ccv
19  *       r9 = contents of ar.csd
20  *      r10 = contents of ar.ssd
21  *      r11 = FPSR_DEFAULT
22  *      r12 = kernel sp (kernel virtual address)
23  *      r13 = points to current task_struct (kernel virtual address)
24  *      p15 = TRUE if psr.i is set in cr.ipsr
25  *      predicate registers (other than p2, p3, and p15), b6, r3, r14, r15:
26  *              preserved
27  *
28  * Note that psr.ic is NOT turned on by this macro.  This is so that
29  * we can pass interruption state as arguments to a handler.
30  */
31 #define DO_SAVE_MIN(COVER,SAVE_IFS,EXTRA)                                                       \
32         mov r16=IA64_KR(CURRENT);       /* M */                                                 \
33         mov r27=ar.rsc;                 /* M */                                                 \
34         mov r20=r1;                     /* A */                                                 \
35         mov r25=ar.unat;                /* M */                                                 \
36         mov r29=cr.ipsr;                /* M */                                                 \
37         mov r26=ar.pfs;                 /* I */                                                 \
38         mov r28=cr.iip;                 /* M */                                                 \
39         mov r21=ar.fpsr;                /* M */                                                 \
40         COVER;                          /* B;; (or nothing) */                                  \
41         ;;                                                                                      \
42         adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16;                                         \
43         ;;                                                                                      \
44         ld1 r17=[r16];                          /* load current->thread.on_ustack flag */       \
45         st1 [r16]=r0;                           /* clear current->thread.on_ustack flag */      \
46         adds r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16                                          \
47         /* switch from user to kernel RBS: */                                                   \
48         ;;                                                                                      \
49         invala;                         /* M */                                                 \
50         SAVE_IFS;                                                                               \
51         cmp.eq pKStk,pUStk=r0,r17;              /* are we in kernel mode already? */            \
52         ;;                                                                                      \
53 (pUStk) mov ar.rsc=0;           /* set enforced lazy mode, pl 0, little-endian, loadrs=0 */     \
54         ;;                                                                                      \
55 (pUStk) mov.m r24=ar.rnat;                                                                      \
56 (pUStk) addl r22=IA64_RBS_OFFSET,r1;                    /* compute base of RBS */               \
57 (pKStk) mov r1=sp;                                      /* get sp  */                           \
58         ;;                                                                                      \
59 (pUStk) lfetch.fault.excl.nt1 [r22];                                                            \
60 (pUStk) addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1;   /* compute base of memory stack */      \
61 (pUStk) mov r23=ar.bspstore;                            /* save ar.bspstore */                  \
62         ;;                                                                                      \
63 (pUStk) mov ar.bspstore=r22;                            /* switch to kernel RBS */              \
64 (pKStk) addl r1=-IA64_PT_REGS_SIZE,r1;                  /* if in kernel mode, use sp (r12) */   \
65         ;;                                                                                      \
66 (pUStk) mov r18=ar.bsp;                                                                         \
67 (pUStk) mov ar.rsc=0x3;         /* set eager mode, pl 0, little-endian, loadrs=0 */             \
68         adds r17=2*L1_CACHE_BYTES,r1;           /* really: biggest cache-line size */           \
69         adds r16=PT(CR_IPSR),r1;                                                                \
70         ;;                                                                                      \
71         lfetch.fault.excl.nt1 [r17],L1_CACHE_BYTES;                                             \
72         st8 [r16]=r29;          /* save cr.ipsr */                                              \
73         ;;                                                                                      \
74         lfetch.fault.excl.nt1 [r17];                                                            \
75         tbit.nz p15,p0=r29,IA64_PSR_I_BIT;                                                      \
76         mov r29=b0                                                                              \
77         ;;                                                                                      \
78         adds r16=PT(R8),r1;     /* initialize first base pointer */                             \
79         adds r17=PT(R9),r1;     /* initialize second base pointer */                            \
80 (pKStk) mov r18=r0;             /* make sure r18 isn't NaT */                                   \
81         ;;                                                                                      \
82 .mem.offset 0,0; st8.spill [r16]=r8,16;                                                         \
83 .mem.offset 8,0; st8.spill [r17]=r9,16;                                                         \
84         ;;                                                                                      \
85 .mem.offset 0,0; st8.spill [r16]=r10,24;                                                        \
86 .mem.offset 8,0; st8.spill [r17]=r11,24;                                                        \
87         ;;                                                                                      \
88         st8 [r16]=r28,16;       /* save cr.iip */                                               \
89         st8 [r17]=r30,16;       /* save cr.ifs */                                               \
90 (pUStk) sub r18=r18,r22;        /* r18=RSE.ndirty*8 */                                          \
91         mov r8=ar.ccv;                                                                          \
92         mov r9=ar.csd;                                                                          \
93         mov r10=ar.ssd;                                                                         \
94         movl r11=FPSR_DEFAULT;   /* L-unit */                                                   \
95         ;;                                                                                      \
96         st8 [r16]=r25,16;       /* save ar.unat */                                              \
97         st8 [r17]=r26,16;       /* save ar.pfs */                                               \
98         shl r18=r18,16;         /* compute ar.rsc to be used for "loadrs" */                    \
99         ;;                                                                                      \
100         st8 [r16]=r27,16;       /* save ar.rsc */                                               \
101 (pUStk) st8 [r17]=r24,16;       /* save ar.rnat */                                              \
102 (pKStk) adds r17=16,r17;        /* skip over ar_rnat field */                                   \
103         ;;                      /* avoid RAW on r16 & r17 */                                    \
104 (pUStk) st8 [r16]=r23,16;       /* save ar.bspstore */                                          \
105         st8 [r17]=r31,16;       /* save predicates */                                           \
106 (pKStk) adds r16=16,r16;        /* skip over ar_bspstore field */                               \
107         ;;                                                                                      \
108         st8 [r16]=r29,16;       /* save b0 */                                                   \
109         st8 [r17]=r18,16;       /* save ar.rsc value for "loadrs" */                            \
110         cmp.eq pNonSys,pSys=r0,r0       /* initialize pSys=0, pNonSys=1 */                      \
111         ;;                                                                                      \
112 .mem.offset 0,0; st8.spill [r16]=r20,16;        /* save original r1 */                          \
113 .mem.offset 8,0; st8.spill [r17]=r12,16;                                                        \
114         adds r12=-16,r1;        /* switch to kernel memory stack (with 16 bytes of scratch) */  \
115         ;;                                                                                      \
116 .mem.offset 0,0; st8.spill [r16]=r13,16;                                                        \
117 .mem.offset 8,0; st8.spill [r17]=r21,16;        /* save ar.fpsr */                              \
118         mov r13=IA64_KR(CURRENT);       /* establish `current' */                               \
119         ;;                                                                                      \
120 .mem.offset 0,0; st8.spill [r16]=r15,16;                                                        \
121 .mem.offset 8,0; st8.spill [r17]=r14,16;                                                        \
122         ;;                                                                                      \
123 .mem.offset 0,0; st8.spill [r16]=r2,16;                                                         \
124 .mem.offset 8,0; st8.spill [r17]=r3,16;                                                         \
125         adds r2=IA64_PT_REGS_R16_OFFSET,r1;                                                     \
126         ;;                                                                                      \
127         EXTRA;                                                                                  \
128         movl r1=__gp;           /* establish kernel global pointer */                           \
129         ;;                                                                                      \
130         bsw.1;                  /* switch back to bank 1 (must be last in insn group) */        \
131         ;;
132
133 /*
134  * SAVE_REST saves the remainder of pt_regs (with psr.ic on).
135  *
136  * Assumed state upon entry:
137  *      psr.ic: on
138  *      r2:     points to &pt_regs.r16
139  *      r3:     points to &pt_regs.r17
140  *      r8:     contents of ar.ccv
141  *      r9:     contents of ar.csd
142  *      r10:    contents of ar.ssd
143  *      r11:    FPSR_DEFAULT
144  *
145  * Registers r14 and r15 are guaranteed not to be touched by SAVE_REST.
146  */
147 #define SAVE_REST                               \
148 .mem.offset 0,0; st8.spill [r2]=r16,16;         \
149 .mem.offset 8,0; st8.spill [r3]=r17,16;         \
150         ;;                                      \
151 .mem.offset 0,0; st8.spill [r2]=r18,16;         \
152 .mem.offset 8,0; st8.spill [r3]=r19,16;         \
153         ;;                                      \
154 .mem.offset 0,0; st8.spill [r2]=r20,16;         \
155 .mem.offset 8,0; st8.spill [r3]=r21,16;         \
156         mov r18=b6;                             \
157         ;;                                      \
158 .mem.offset 0,0; st8.spill [r2]=r22,16;         \
159 .mem.offset 8,0; st8.spill [r3]=r23,16;         \
160         mov r19=b7;                             \
161         ;;                                      \
162 .mem.offset 0,0; st8.spill [r2]=r24,16;         \
163 .mem.offset 8,0; st8.spill [r3]=r25,16;         \
164         ;;                                      \
165 .mem.offset 0,0; st8.spill [r2]=r26,16;         \
166 .mem.offset 8,0; st8.spill [r3]=r27,16;         \
167         ;;                                      \
168 .mem.offset 0,0; st8.spill [r2]=r28,16;         \
169 .mem.offset 8,0; st8.spill [r3]=r29,16;         \
170         ;;                                      \
171 .mem.offset 0,0; st8.spill [r2]=r30,16;         \
172 .mem.offset 8,0; st8.spill [r3]=r31,32;         \
173         ;;                                      \
174         mov ar.fpsr=r11;        /* M-unit */    \
175         st8 [r2]=r8,8;          /* ar.ccv */    \
176         adds r24=PT(B6)-PT(F7),r3;              \
177         ;;                                      \
178         stf.spill [r2]=f6,32;                   \
179         stf.spill [r3]=f7,32;                   \
180         ;;                                      \
181         stf.spill [r2]=f8,32;                   \
182         stf.spill [r3]=f9,32;                   \
183         ;;                                      \
184         stf.spill [r2]=f10;                     \
185         stf.spill [r3]=f11;                     \
186         adds r25=PT(B7)-PT(F11),r3;             \
187         ;;                                      \
188         st8 [r24]=r18,16;       /* b6 */        \
189         st8 [r25]=r19,16;       /* b7 */        \
190         ;;                                      \
191         st8 [r24]=r9;           /* ar.csd */    \
192         st8 [r25]=r10;          /* ar.ssd */    \
193         ;;
194
195 #define SAVE_MIN_WITH_COVER     DO_SAVE_MIN(cover, mov r30=cr.ifs,)
196 #define SAVE_MIN_WITH_COVER_R19 DO_SAVE_MIN(cover, mov r30=cr.ifs, mov r15=r19)
197 #define SAVE_MIN                DO_SAVE_MIN(     , mov r30=r0, )