xref: /openbmc/linux/arch/ia64/kernel/minstate.h (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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, )
198