xref: /openbmc/linux/arch/ia64/kernel/minstate.h (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 #include <linux/config.h>
2 
3 #include <asm/cache.h>
4 
5 #include "entry.h"
6 
7 /*
8  * For ivt.s we want to access the stack virtually so we don't have to disable translation
9  * on interrupts.
10  *
11  *  On entry:
12  *	r1:	pointer to current task (ar.k6)
13  */
14 #define MINSTATE_START_SAVE_MIN_VIRT								\
15 (pUStk)	mov ar.rsc=0;		/* set enforced lazy mode, pl 0, little-endian, loadrs=0 */	\
16 	;;											\
17 (pUStk)	mov.m r24=ar.rnat;									\
18 (pUStk)	addl r22=IA64_RBS_OFFSET,r1;			/* compute base of RBS */		\
19 (pKStk) mov r1=sp;					/* get sp  */				\
20 	;;											\
21 (pUStk) lfetch.fault.excl.nt1 [r22];								\
22 (pUStk)	addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1;	/* compute base of memory stack */	\
23 (pUStk)	mov r23=ar.bspstore;				/* save ar.bspstore */			\
24 	;;											\
25 (pUStk)	mov ar.bspstore=r22;				/* switch to kernel RBS */		\
26 (pKStk) addl r1=-IA64_PT_REGS_SIZE,r1;			/* if in kernel mode, use sp (r12) */	\
27 	;;											\
28 (pUStk)	mov r18=ar.bsp;										\
29 (pUStk)	mov ar.rsc=0x3;		/* set eager mode, pl 0, little-endian, loadrs=0 */
30 
31 #define MINSTATE_END_SAVE_MIN_VIRT								\
32 	bsw.1;			/* switch back to bank 1 (must be last in insn group) */	\
33 	;;
34 
35 /*
36  * For mca_asm.S we want to access the stack physically since the state is saved before we
37  * go virtual and don't want to destroy the iip or ipsr.
38  */
39 #define MINSTATE_START_SAVE_MIN_PHYS								\
40 (pKStk) mov r3=IA64_KR(PER_CPU_DATA);;								\
41 (pKStk) addl r3=THIS_CPU(ia64_mca_data),r3;;							\
42 (pKStk) ld8 r3 = [r3];;										\
43 (pKStk) addl r3=IA64_MCA_CPU_INIT_STACK_OFFSET,r3;;						\
44 (pKStk) addl sp=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r3;						\
45 (pUStk)	mov ar.rsc=0;		/* set enforced lazy mode, pl 0, little-endian, loadrs=0 */	\
46 (pUStk)	addl r22=IA64_RBS_OFFSET,r1;		/* compute base of register backing store */	\
47 	;;											\
48 (pUStk)	mov r24=ar.rnat;									\
49 (pUStk)	addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1;	/* compute base of memory stack */	\
50 (pUStk)	mov r23=ar.bspstore;				/* save ar.bspstore */			\
51 (pUStk)	dep r22=-1,r22,61,3;			/* compute kernel virtual addr of RBS */	\
52 	;;											\
53 (pKStk) addl r1=-IA64_PT_REGS_SIZE,r1;		/* if in kernel mode, use sp (r12) */		\
54 (pUStk)	mov ar.bspstore=r22;			/* switch to kernel RBS */			\
55 	;;											\
56 (pUStk)	mov r18=ar.bsp;										\
57 (pUStk)	mov ar.rsc=0x3;		/* set eager mode, pl 0, little-endian, loadrs=0 */		\
58 
59 #define MINSTATE_END_SAVE_MIN_PHYS								\
60 	dep r12=-1,r12,61,3;		/* make sp a kernel virtual address */			\
61 	;;
62 
63 #ifdef MINSTATE_VIRT
64 # define MINSTATE_GET_CURRENT(reg)	mov reg=IA64_KR(CURRENT)
65 # define MINSTATE_START_SAVE_MIN	MINSTATE_START_SAVE_MIN_VIRT
66 # define MINSTATE_END_SAVE_MIN		MINSTATE_END_SAVE_MIN_VIRT
67 #endif
68 
69 #ifdef MINSTATE_PHYS
70 # define MINSTATE_GET_CURRENT(reg)	mov reg=IA64_KR(CURRENT);; tpa reg=reg
71 # define MINSTATE_START_SAVE_MIN	MINSTATE_START_SAVE_MIN_PHYS
72 # define MINSTATE_END_SAVE_MIN		MINSTATE_END_SAVE_MIN_PHYS
73 #endif
74 
75 /*
76  * DO_SAVE_MIN switches to the kernel stacks (if necessary) and saves
77  * the minimum state necessary that allows us to turn psr.ic back
78  * on.
79  *
80  * Assumed state upon entry:
81  *	psr.ic: off
82  *	r31:	contains saved predicates (pr)
83  *
84  * Upon exit, the state is as follows:
85  *	psr.ic: off
86  *	 r2 = points to &pt_regs.r16
87  *	 r8 = contents of ar.ccv
88  *	 r9 = contents of ar.csd
89  *	r10 = contents of ar.ssd
90  *	r11 = FPSR_DEFAULT
91  *	r12 = kernel sp (kernel virtual address)
92  *	r13 = points to current task_struct (kernel virtual address)
93  *	p15 = TRUE if psr.i is set in cr.ipsr
94  *	predicate registers (other than p2, p3, and p15), b6, r3, r14, r15:
95  *		preserved
96  *
97  * Note that psr.ic is NOT turned on by this macro.  This is so that
98  * we can pass interruption state as arguments to a handler.
99  */
100 #define DO_SAVE_MIN(COVER,SAVE_IFS,EXTRA)							\
101 	MINSTATE_GET_CURRENT(r16);	/* M (or M;;I) */					\
102 	mov r27=ar.rsc;			/* M */							\
103 	mov r20=r1;			/* A */							\
104 	mov r25=ar.unat;		/* M */							\
105 	mov r29=cr.ipsr;		/* M */							\
106 	mov r26=ar.pfs;			/* I */							\
107 	mov r28=cr.iip;			/* M */							\
108 	mov r21=ar.fpsr;		/* M */							\
109 	COVER;				/* B;; (or nothing) */					\
110 	;;											\
111 	adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16;						\
112 	;;											\
113 	ld1 r17=[r16];				/* load current->thread.on_ustack flag */	\
114 	st1 [r16]=r0;				/* clear current->thread.on_ustack flag */	\
115 	adds r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16						\
116 	/* switch from user to kernel RBS: */							\
117 	;;											\
118 	invala;				/* M */							\
119 	SAVE_IFS;										\
120 	cmp.eq pKStk,pUStk=r0,r17;		/* are we in kernel mode already? */		\
121 	;;											\
122 	MINSTATE_START_SAVE_MIN									\
123 	adds r17=2*L1_CACHE_BYTES,r1;		/* really: biggest cache-line size */		\
124 	adds r16=PT(CR_IPSR),r1;								\
125 	;;											\
126 	lfetch.fault.excl.nt1 [r17],L1_CACHE_BYTES;						\
127 	st8 [r16]=r29;		/* save cr.ipsr */						\
128 	;;											\
129 	lfetch.fault.excl.nt1 [r17];								\
130 	tbit.nz p15,p0=r29,IA64_PSR_I_BIT;							\
131 	mov r29=b0										\
132 	;;											\
133 	adds r16=PT(R8),r1;	/* initialize first base pointer */				\
134 	adds r17=PT(R9),r1;	/* initialize second base pointer */				\
135 (pKStk)	mov r18=r0;		/* make sure r18 isn't NaT */					\
136 	;;											\
137 .mem.offset 0,0; st8.spill [r16]=r8,16;								\
138 .mem.offset 8,0; st8.spill [r17]=r9,16;								\
139         ;;											\
140 .mem.offset 0,0; st8.spill [r16]=r10,24;							\
141 .mem.offset 8,0; st8.spill [r17]=r11,24;							\
142         ;;											\
143 	st8 [r16]=r28,16;	/* save cr.iip */						\
144 	st8 [r17]=r30,16;	/* save cr.ifs */						\
145 (pUStk)	sub r18=r18,r22;	/* r18=RSE.ndirty*8 */						\
146 	mov r8=ar.ccv;										\
147 	mov r9=ar.csd;										\
148 	mov r10=ar.ssd;										\
149 	movl r11=FPSR_DEFAULT;   /* L-unit */							\
150 	;;											\
151 	st8 [r16]=r25,16;	/* save ar.unat */						\
152 	st8 [r17]=r26,16;	/* save ar.pfs */						\
153 	shl r18=r18,16;		/* compute ar.rsc to be used for "loadrs" */			\
154 	;;											\
155 	st8 [r16]=r27,16;	/* save ar.rsc */						\
156 (pUStk)	st8 [r17]=r24,16;	/* save ar.rnat */						\
157 (pKStk)	adds r17=16,r17;	/* skip over ar_rnat field */					\
158 	;;			/* avoid RAW on r16 & r17 */					\
159 (pUStk)	st8 [r16]=r23,16;	/* save ar.bspstore */						\
160 	st8 [r17]=r31,16;	/* save predicates */						\
161 (pKStk)	adds r16=16,r16;	/* skip over ar_bspstore field */				\
162 	;;											\
163 	st8 [r16]=r29,16;	/* save b0 */							\
164 	st8 [r17]=r18,16;	/* save ar.rsc value for "loadrs" */				\
165 	cmp.eq pNonSys,pSys=r0,r0	/* initialize pSys=0, pNonSys=1 */			\
166 	;;											\
167 .mem.offset 0,0; st8.spill [r16]=r20,16;	/* save original r1 */				\
168 .mem.offset 8,0; st8.spill [r17]=r12,16;							\
169 	adds r12=-16,r1;	/* switch to kernel memory stack (with 16 bytes of scratch) */	\
170 	;;											\
171 .mem.offset 0,0; st8.spill [r16]=r13,16;							\
172 .mem.offset 8,0; st8.spill [r17]=r21,16;	/* save ar.fpsr */				\
173 	mov r13=IA64_KR(CURRENT);	/* establish `current' */				\
174 	;;											\
175 .mem.offset 0,0; st8.spill [r16]=r15,16;							\
176 .mem.offset 8,0; st8.spill [r17]=r14,16;							\
177 	;;											\
178 .mem.offset 0,0; st8.spill [r16]=r2,16;								\
179 .mem.offset 8,0; st8.spill [r17]=r3,16;								\
180 	adds r2=IA64_PT_REGS_R16_OFFSET,r1;							\
181 	;;											\
182 	EXTRA;											\
183 	movl r1=__gp;		/* establish kernel global pointer */				\
184 	;;											\
185 	MINSTATE_END_SAVE_MIN
186 
187 /*
188  * SAVE_REST saves the remainder of pt_regs (with psr.ic on).
189  *
190  * Assumed state upon entry:
191  *	psr.ic: on
192  *	r2:	points to &pt_regs.r16
193  *	r3:	points to &pt_regs.r17
194  *	r8:	contents of ar.ccv
195  *	r9:	contents of ar.csd
196  *	r10:	contents of ar.ssd
197  *	r11:	FPSR_DEFAULT
198  *
199  * Registers r14 and r15 are guaranteed not to be touched by SAVE_REST.
200  */
201 #define SAVE_REST				\
202 .mem.offset 0,0; st8.spill [r2]=r16,16;		\
203 .mem.offset 8,0; st8.spill [r3]=r17,16;		\
204 	;;					\
205 .mem.offset 0,0; st8.spill [r2]=r18,16;		\
206 .mem.offset 8,0; st8.spill [r3]=r19,16;		\
207 	;;					\
208 .mem.offset 0,0; st8.spill [r2]=r20,16;		\
209 .mem.offset 8,0; st8.spill [r3]=r21,16;		\
210 	mov r18=b6;				\
211 	;;					\
212 .mem.offset 0,0; st8.spill [r2]=r22,16;		\
213 .mem.offset 8,0; st8.spill [r3]=r23,16;		\
214 	mov r19=b7;				\
215 	;;					\
216 .mem.offset 0,0; st8.spill [r2]=r24,16;		\
217 .mem.offset 8,0; st8.spill [r3]=r25,16;		\
218 	;;					\
219 .mem.offset 0,0; st8.spill [r2]=r26,16;		\
220 .mem.offset 8,0; st8.spill [r3]=r27,16;		\
221 	;;					\
222 .mem.offset 0,0; st8.spill [r2]=r28,16;		\
223 .mem.offset 8,0; st8.spill [r3]=r29,16;		\
224 	;;					\
225 .mem.offset 0,0; st8.spill [r2]=r30,16;		\
226 .mem.offset 8,0; st8.spill [r3]=r31,32;		\
227 	;;					\
228 	mov ar.fpsr=r11;	/* M-unit */	\
229 	st8 [r2]=r8,8;		/* ar.ccv */	\
230 	adds r24=PT(B6)-PT(F7),r3;		\
231 	;;					\
232 	stf.spill [r2]=f6,32;			\
233 	stf.spill [r3]=f7,32;			\
234 	;;					\
235 	stf.spill [r2]=f8,32;			\
236 	stf.spill [r3]=f9,32;			\
237 	;;					\
238 	stf.spill [r2]=f10;			\
239 	stf.spill [r3]=f11;			\
240 	adds r25=PT(B7)-PT(F11),r3;		\
241 	;;					\
242 	st8 [r24]=r18,16;       /* b6 */	\
243 	st8 [r25]=r19,16;       /* b7 */	\
244 	;;					\
245 	st8 [r24]=r9;        	/* ar.csd */	\
246 	st8 [r25]=r10;      	/* ar.ssd */	\
247 	;;
248 
249 #define SAVE_MIN_WITH_COVER	DO_SAVE_MIN(cover, mov r30=cr.ifs,)
250 #define SAVE_MIN_WITH_COVER_R19	DO_SAVE_MIN(cover, mov r30=cr.ifs, mov r15=r19)
251 #define SAVE_MIN		DO_SAVE_MIN(     , mov r30=r0, )
252