xref: /openbsd-src/sys/arch/powerpc/powerpc/fpu.c (revision 4a100a2e77d2a09add5bcff297c3ebd06456e53e)
1 /*	$OpenBSD: fpu.c,v 1.14 2014/07/09 08:34:49 deraadt Exp $	*/
2 /*	$NetBSD: fpu.c,v 1.1 1996/09/30 16:34:44 ws Exp $	*/
3 
4 /*
5  * Copyright (C) 1996 Wolfgang Solfrank.
6  * Copyright (C) 1996 TooLs GmbH.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by TooLs GmbH.
20  * 4. The name of TooLs GmbH may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/proc.h>
37 #include <sys/user.h>
38 
39 #include <machine/fpu.h>
40 #include <machine/psl.h>
41 
42 void
enable_fpu(struct proc * p)43 enable_fpu(struct proc *p)
44 {
45 	struct cpu_info *ci = curcpu();
46 	struct pcb *pcb = &p->p_addr->u_pcb;
47 	struct trapframe *tf = trapframe(p);
48 	int msr;
49 
50 	if (!(pcb->pcb_flags & PCB_FPU)) {
51 		bzero(&pcb->pcb_fpu, sizeof pcb->pcb_fpu);
52 		pcb->pcb_flags |= PCB_FPU;
53 	}
54 
55 	if (pcb->pcb_fpcpu != NULL || ci->ci_fpuproc != NULL) {
56 		printf("attempting to restore fpu state when in use pcb %p"
57 		    " fpproc %p\n", pcb->pcb_fpcpu, ci->ci_fpuproc);
58 	}
59 	msr = ppc_mfmsr();
60 	ppc_mtmsr((msr  & ~PSL_EE) | PSL_FP);
61 	__asm volatile("isync");
62 
63 	asm volatile ("lfd 0,0(%0); mtfsf 0xff,0" :: "b"(&pcb->pcb_fpu.fpcsr));
64 	asm ("lfd 0,0(%0);"
65 	     "lfd 1,8(%0);"
66 	     "lfd 2,16(%0);"
67 	     "lfd 3,24(%0);"
68 	     "lfd 4,32(%0);"
69 	     "lfd 5,40(%0);"
70 	     "lfd 6,48(%0);"
71 	     "lfd 7,56(%0);"
72 	     "lfd 8,64(%0);"
73 	     "lfd 9,72(%0);"
74 	     "lfd 10,80(%0);"
75 	     "lfd 11,88(%0);"
76 	     "lfd 12,96(%0);"
77 	     "lfd 13,104(%0);"
78 	     "lfd 14,112(%0);"
79 	     "lfd 15,120(%0);"
80 	     "lfd 16,128(%0);"
81 	     "lfd 17,136(%0);"
82 	     "lfd 18,144(%0);"
83 	     "lfd 19,152(%0);"
84 	     "lfd 20,160(%0);"
85 	     "lfd 21,168(%0);"
86 	     "lfd 22,176(%0);"
87 	     "lfd 23,184(%0);"
88 	     "lfd 24,192(%0);"
89 	     "lfd 25,200(%0);"
90 	     "lfd 26,208(%0);"
91 	     "lfd 27,216(%0);"
92 	     "lfd 28,224(%0);"
93 	     "lfd 29,232(%0);"
94 	     "lfd 30,240(%0);"
95 	     "lfd 31,248(%0)" :: "b"(&pcb->pcb_fpu.fpr[0]));
96 	ci->ci_fpuproc = p;
97 	pcb->pcb_fpcpu = ci;
98 	tf->srr1 |= PSL_FP;
99 	ppc_mtmsr(msr);
100 	__asm volatile("isync");
101 }
102 
103 void
save_fpu(void)104 save_fpu(void)
105 {
106 	struct cpu_info *ci = curcpu();
107 	struct pcb *pcb;
108 	struct proc *p;
109 	struct trapframe *tf;
110 	int msr;
111 
112 	msr = ppc_mfmsr();
113 	ppc_mtmsr((msr  & ~PSL_EE) | PSL_FP);
114 
115 	p = ci->ci_fpuproc;
116 
117 	if (p == NULL) {
118 		ppc_mtmsr(msr);
119 		return;
120 	}
121 
122 	pcb = &p->p_addr->u_pcb;
123 
124 	__asm volatile("isync");
125 
126 	asm ("stfd 0,0(%0);"
127 	     "stfd 1,8(%0);"
128 	     "stfd 2,16(%0);"
129 	     "stfd 3,24(%0);"
130 	     "stfd 4,32(%0);"
131 	     "stfd 5,40(%0);"
132 	     "stfd 6,48(%0);"
133 	     "stfd 7,56(%0);"
134 	     "stfd 8,64(%0);"
135 	     "stfd 9,72(%0);"
136 	     "stfd 10,80(%0);"
137 	     "stfd 11,88(%0);"
138 	     "stfd 12,96(%0);"
139 	     "stfd 13,104(%0);"
140 	     "stfd 14,112(%0);"
141 	     "stfd 15,120(%0);"
142 	     "stfd 16,128(%0);"
143 	     "stfd 17,136(%0);"
144 	     "stfd 18,144(%0);"
145 	     "stfd 19,152(%0);"
146 	     "stfd 20,160(%0);"
147 	     "stfd 21,168(%0);"
148 	     "stfd 22,176(%0);"
149 	     "stfd 23,184(%0);"
150 	     "stfd 24,192(%0);"
151 	     "stfd 25,200(%0);"
152 	     "stfd 26,208(%0);"
153 	     "stfd 27,216(%0);"
154 	     "stfd 28,224(%0);"
155 	     "stfd 29,232(%0);"
156 	     "stfd 30,240(%0);"
157 	     "stfd 31,248(%0)" :: "b"(&pcb->pcb_fpu.fpr[0]));
158 	asm volatile ("mffs 0; stfd 0,0(%0)" :: "b"(&pcb->pcb_fpu.fpcsr));
159 	asm ("lfd 0,0(%0);" :: "b"(&pcb->pcb_fpu.fpr[0]));
160 
161 	tf = trapframe(ci->ci_fpuproc);
162 	tf->srr1 &= ~PSL_FP;
163 	ci->ci_fpuproc = NULL;
164 	pcb->pcb_fpcpu = NULL;
165 
166 	ppc_mtmsr(msr);
167 	__asm volatile("isync");
168 }
169