xref: /openbmc/linux/arch/ia64/kernel/minstate.h (revision c4e78957)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #include <asm/cache.h>
4 
5 #include "entry.h"
6 #include <asm/native/inst.h>
7 
8 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
9 /* read ar.itc in advance, and use it before leaving bank 0 */
10 #define ACCOUNT_GET_STAMP				\
11 (pUStk) mov.m r20=ar.itc;
12 #define ACCOUNT_SYS_ENTER				\
13 (pUStk) br.call.spnt rp=account_sys_enter		\
14 	;;
15 #else
16 #define ACCOUNT_GET_STAMP
17 #define ACCOUNT_SYS_ENTER
18 #endif
19 
20 .section ".data..patch.rse", "a"
21 .previous
22 
23 /*
24  * DO_SAVE_MIN switches to the kernel stacks (if necessary) and saves
25  * the minimum state necessary that allows us to turn psr.ic back
26  * on.
27  *
28  * Assumed state upon entry:
29  *	psr.ic: off
30  *	r31:	contains saved predicates (pr)
31  *
32  * Upon exit, the state is as follows:
33  *	psr.ic: off
34  *	 r2 = points to &pt_regs.r16
35  *	 r8 = contents of ar.ccv
36  *	 r9 = contents of ar.csd
37  *	r10 = contents of ar.ssd
38  *	r11 = FPSR_DEFAULT
39  *	r12 = kernel sp (kernel virtual address)
40  *	r13 = points to current task_struct (kernel virtual address)
41  *	p15 = TRUE if psr.i is set in cr.ipsr
42  *	predicate registers (other than p2, p3, and p15), b6, r3, r14, r15:
43  *		preserved
44  *
45  * Note that psr.ic is NOT turned on by this macro.  This is so that
46  * we can pass interruption state as arguments to a handler.
47  */
48 #define IA64_NATIVE_DO_SAVE_MIN(__COVER,SAVE_IFS,EXTRA,WORKAROUND)				\
49 	mov r16=IA64_KR(CURRENT);	/* M */							\
50 	mov r27=ar.rsc;			/* M */							\
51 	mov r20=r1;			/* A */							\
52 	mov r25=ar.unat;		/* M */							\
53 	MOV_FROM_IPSR(p0,r29);		/* M */							\
54 	mov r26=ar.pfs;			/* I */							\
55 	MOV_FROM_IIP(r28);			/* M */						\
56 	mov r21=ar.fpsr;		/* M */							\
57 	__COVER;				/* B;; (or nothing) */				\
58 	;;											\
59 	adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16;						\
60 	;;											\
61 	ld1 r17=[r16];				/* load current->thread.on_ustack flag */	\
62 	st1 [r16]=r0;				/* clear current->thread.on_ustack flag */	\
63 	adds r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16						\
64 	/* switch from user to kernel RBS: */							\
65 	;;											\
66 	invala;				/* M */							\
67 	SAVE_IFS;										\
68 	cmp.eq pKStk,pUStk=r0,r17;		/* are we in kernel mode already? */		\
69 	;;											\
70 (pUStk)	mov ar.rsc=0;		/* set enforced lazy mode, pl 0, little-endian, loadrs=0 */	\
71 	;;											\
72 (pUStk)	mov.m r24=ar.rnat;									\
73 (pUStk)	addl r22=IA64_RBS_OFFSET,r1;			/* compute base of RBS */		\
74 (pKStk) mov r1=sp;					/* get sp  */				\
75 	;;											\
76 (pUStk) lfetch.fault.excl.nt1 [r22];								\
77 (pUStk)	addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1;	/* compute base of memory stack */	\
78 (pUStk)	mov r23=ar.bspstore;				/* save ar.bspstore */			\
79 	;;											\
80 (pUStk)	mov ar.bspstore=r22;				/* switch to kernel RBS */		\
81 (pKStk) addl r1=-IA64_PT_REGS_SIZE,r1;			/* if in kernel mode, use sp (r12) */	\
82 	;;											\
83 (pUStk)	mov r18=ar.bsp;										\
84 (pUStk)	mov ar.rsc=0x3;		/* set eager mode, pl 0, little-endian, loadrs=0 */		\
85 	adds r17=2*L1_CACHE_BYTES,r1;		/* really: biggest cache-line size */		\
86 	adds r16=PT(CR_IPSR),r1;								\
87 	;;											\
88 	lfetch.fault.excl.nt1 [r17],L1_CACHE_BYTES;						\
89 	st8 [r16]=r29;		/* save cr.ipsr */						\
90 	;;											\
91 	lfetch.fault.excl.nt1 [r17];								\
92 	tbit.nz p15,p0=r29,IA64_PSR_I_BIT;							\
93 	mov r29=b0										\
94 	;;											\
95 	WORKAROUND;										\
96 	adds r16=PT(R8),r1;	/* initialize first base pointer */				\
97 	adds r17=PT(R9),r1;	/* initialize second base pointer */				\
98 (pKStk)	mov r18=r0;		/* make sure r18 isn't NaT */					\
99 	;;											\
100 .mem.offset 0,0; st8.spill [r16]=r8,16;								\
101 .mem.offset 8,0; st8.spill [r17]=r9,16;								\
102         ;;											\
103 .mem.offset 0,0; st8.spill [r16]=r10,24;							\
104 .mem.offset 8,0; st8.spill [r17]=r11,24;							\
105         ;;											\
106 	st8 [r16]=r28,16;	/* save cr.iip */						\
107 	st8 [r17]=r30,16;	/* save cr.ifs */						\
108 (pUStk)	sub r18=r18,r22;	/* r18=RSE.ndirty*8 */						\
109 	mov r8=ar.ccv;										\
110 	mov r9=ar.csd;										\
111 	mov r10=ar.ssd;										\
112 	movl r11=FPSR_DEFAULT;   /* L-unit */							\
113 	;;											\
114 	st8 [r16]=r25,16;	/* save ar.unat */						\
115 	st8 [r17]=r26,16;	/* save ar.pfs */						\
116 	shl r18=r18,16;		/* compute ar.rsc to be used for "loadrs" */			\
117 	;;											\
118 	st8 [r16]=r27,16;	/* save ar.rsc */						\
119 (pUStk)	st8 [r17]=r24,16;	/* save ar.rnat */						\
120 (pKStk)	adds r17=16,r17;	/* skip over ar_rnat field */					\
121 	;;			/* avoid RAW on r16 & r17 */					\
122 (pUStk)	st8 [r16]=r23,16;	/* save ar.bspstore */						\
123 	st8 [r17]=r31,16;	/* save predicates */						\
124 (pKStk)	adds r16=16,r16;	/* skip over ar_bspstore field */				\
125 	;;											\
126 	st8 [r16]=r29,16;	/* save b0 */							\
127 	st8 [r17]=r18,16;	/* save ar.rsc value for "loadrs" */				\
128 	cmp.eq pNonSys,pSys=r0,r0	/* initialize pSys=0, pNonSys=1 */			\
129 	;;											\
130 .mem.offset 0,0; st8.spill [r16]=r20,16;	/* save original r1 */				\
131 .mem.offset 8,0; st8.spill [r17]=r12,16;							\
132 	adds r12=-16,r1;	/* switch to kernel memory stack (with 16 bytes of scratch) */	\
133 	;;											\
134 .mem.offset 0,0; st8.spill [r16]=r13,16;							\
135 .mem.offset 8,0; st8.spill [r17]=r21,16;	/* save ar.fpsr */				\
136 	mov r13=IA64_KR(CURRENT);	/* establish `current' */				\
137 	;;											\
138 .mem.offset 0,0; st8.spill [r16]=r15,16;							\
139 .mem.offset 8,0; st8.spill [r17]=r14,16;							\
140 	;;											\
141 .mem.offset 0,0; st8.spill [r16]=r2,16;								\
142 .mem.offset 8,0; st8.spill [r17]=r3,16;								\
143 	ACCOUNT_GET_STAMP									\
144 	adds r2=IA64_PT_REGS_R16_OFFSET,r1;							\
145 	;;											\
146 	EXTRA;											\
147 	movl r1=__gp;		/* establish kernel global pointer */				\
148 	;;											\
149 	ACCOUNT_SYS_ENTER									\
150 	bsw.1;			/* switch back to bank 1 (must be last in insn group) */	\
151 	;;
152 
153 /*
154  * SAVE_REST saves the remainder of pt_regs (with psr.ic on).
155  *
156  * Assumed state upon entry:
157  *	psr.ic: on
158  *	r2:	points to &pt_regs.r16
159  *	r3:	points to &pt_regs.r17
160  *	r8:	contents of ar.ccv
161  *	r9:	contents of ar.csd
162  *	r10:	contents of ar.ssd
163  *	r11:	FPSR_DEFAULT
164  *
165  * Registers r14 and r15 are guaranteed not to be touched by SAVE_REST.
166  */
167 #define SAVE_REST				\
168 .mem.offset 0,0; st8.spill [r2]=r16,16;		\
169 .mem.offset 8,0; st8.spill [r3]=r17,16;		\
170 	;;					\
171 .mem.offset 0,0; st8.spill [r2]=r18,16;		\
172 .mem.offset 8,0; st8.spill [r3]=r19,16;		\
173 	;;					\
174 .mem.offset 0,0; st8.spill [r2]=r20,16;		\
175 .mem.offset 8,0; st8.spill [r3]=r21,16;		\
176 	mov r18=b6;				\
177 	;;					\
178 .mem.offset 0,0; st8.spill [r2]=r22,16;		\
179 .mem.offset 8,0; st8.spill [r3]=r23,16;		\
180 	mov r19=b7;				\
181 	;;					\
182 .mem.offset 0,0; st8.spill [r2]=r24,16;		\
183 .mem.offset 8,0; st8.spill [r3]=r25,16;		\
184 	;;					\
185 .mem.offset 0,0; st8.spill [r2]=r26,16;		\
186 .mem.offset 8,0; st8.spill [r3]=r27,16;		\
187 	;;					\
188 .mem.offset 0,0; st8.spill [r2]=r28,16;		\
189 .mem.offset 8,0; st8.spill [r3]=r29,16;		\
190 	;;					\
191 .mem.offset 0,0; st8.spill [r2]=r30,16;		\
192 .mem.offset 8,0; st8.spill [r3]=r31,32;		\
193 	;;					\
194 	mov ar.fpsr=r11;	/* M-unit */	\
195 	st8 [r2]=r8,8;		/* ar.ccv */	\
196 	adds r24=PT(B6)-PT(F7),r3;		\
197 	;;					\
198 	stf.spill [r2]=f6,32;			\
199 	stf.spill [r3]=f7,32;			\
200 	;;					\
201 	stf.spill [r2]=f8,32;			\
202 	stf.spill [r3]=f9,32;			\
203 	;;					\
204 	stf.spill [r2]=f10;			\
205 	stf.spill [r3]=f11;			\
206 	adds r25=PT(B7)-PT(F11),r3;		\
207 	;;					\
208 	st8 [r24]=r18,16;       /* b6 */	\
209 	st8 [r25]=r19,16;       /* b7 */	\
210 	;;					\
211 	st8 [r24]=r9;        	/* ar.csd */	\
212 	st8 [r25]=r10;      	/* ar.ssd */	\
213 	;;
214 
215 #define RSE_WORKAROUND				\
216 (pUStk) extr.u r17=r18,3,6;			\
217 (pUStk)	sub r16=r18,r22;			\
218 [1:](pKStk)	br.cond.sptk.many 1f;		\
219 	.xdata4 ".data..patch.rse",1b-.		\
220 	;;					\
221 	cmp.ge p6,p7 = 33,r17;			\
222 	;;					\
223 (p6)	mov r17=0x310;				\
224 (p7)	mov r17=0x308;				\
225 	;;					\
226 	cmp.leu p1,p0=r16,r17;			\
227 (p1)	br.cond.sptk.many 1f;			\
228 	dep.z r17=r26,0,62;			\
229 	movl r16=2f;				\
230 	;;					\
231 	mov ar.pfs=r17;				\
232 	dep r27=r0,r27,16,14;			\
233 	mov b0=r16;				\
234 	;;					\
235 	br.ret.sptk b0;				\
236 	;;					\
237 2:						\
238 	mov ar.rsc=r0				\
239 	;;					\
240 	flushrs;				\
241 	;;					\
242 	mov ar.bspstore=r22			\
243 	;;					\
244 	mov r18=ar.bsp;				\
245 	;;					\
246 1:						\
247 	.pred.rel "mutex", pKStk, pUStk
248 
249 #define SAVE_MIN_WITH_COVER	DO_SAVE_MIN(COVER, mov r30=cr.ifs, , RSE_WORKAROUND)
250 #define SAVE_MIN_WITH_COVER_R19	DO_SAVE_MIN(COVER, mov r30=cr.ifs, mov r15=r19, RSE_WORKAROUND)
251 #define SAVE_MIN			DO_SAVE_MIN(     , mov r30=r0, , )
252