2 * SPDX-License-Identifier: BSD-4-Clause
4 * Copyright (C) 1996 Wolfgang Solfrank.
5 * Copyright (C) 1996 TooLs GmbH.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by TooLs GmbH.
19 * 4. The name of TooLs GmbH may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 * $NetBSD: fpu.c,v 1.5 2001/07/22 11:29:46 wiz Exp $
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
39 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/limits.h>
44 #include <machine/fpu.h>
45 #include <machine/pcb.h>
46 #include <machine/psl.h>
49 enable_fpu(struct thread *td)
59 * Save the thread's FPU CPU number, and set the CPU's current
62 td->td_pcb->pcb_fpcpu = PCPU_GET(cpuid);
63 PCPU_SET(fputhread, td);
66 * Enable the FPU for when the thread returns from the exception.
67 * If this is the first time the FPU has been used by the thread,
68 * initialise the FPU registers and FPSCR to 0, and set the flag
69 * to indicate that the FPU is in use.
71 pcb->pcb_flags |= PCB_FPU;
72 if (pcb->pcb_flags & PCB_VSX)
73 tf->srr1 |= PSL_FP | PSL_VSX;
76 if (!(pcb->pcb_flags & PCB_FPREGS)) {
77 memset(&pcb->pcb_fpu, 0, sizeof pcb->pcb_fpu);
78 pcb->pcb_flags |= PCB_FPREGS;
82 * Temporarily enable floating-point so the registers
86 if (pcb->pcb_flags & PCB_VSX)
87 mtmsr(msr | PSL_FP | PSL_VSX);
93 * Load the floating point registers and FPSCR from the PCB.
94 * (A value of 0xff for mtfsf specifies that all 8 4-bit fields
95 * of the saved FPSCR are to be loaded from the FPU reg).
97 __asm __volatile ("lfd 0,0(%0); mtfsf 0xff,0"
98 :: "b"(&pcb->pcb_fpu.fpscr));
100 if (pcb->pcb_flags & PCB_VSX) {
101 #define LFP(n) __asm ("lxvw4x " #n ", 0,%0" \
102 :: "b"(&pcb->pcb_fpu.fpr[n]));
103 LFP(0); LFP(1); LFP(2); LFP(3);
104 LFP(4); LFP(5); LFP(6); LFP(7);
105 LFP(8); LFP(9); LFP(10); LFP(11);
106 LFP(12); LFP(13); LFP(14); LFP(15);
107 LFP(16); LFP(17); LFP(18); LFP(19);
108 LFP(20); LFP(21); LFP(22); LFP(23);
109 LFP(24); LFP(25); LFP(26); LFP(27);
110 LFP(28); LFP(29); LFP(30); LFP(31);
113 #define LFP(n) __asm ("lfd " #n ", 0(%0)" \
114 :: "b"(&pcb->pcb_fpu.fpr[n]));
115 LFP(0); LFP(1); LFP(2); LFP(3);
116 LFP(4); LFP(5); LFP(6); LFP(7);
117 LFP(8); LFP(9); LFP(10); LFP(11);
118 LFP(12); LFP(13); LFP(14); LFP(15);
119 LFP(16); LFP(17); LFP(18); LFP(19);
120 LFP(20); LFP(21); LFP(22); LFP(23);
121 LFP(24); LFP(25); LFP(26); LFP(27);
122 LFP(28); LFP(29); LFP(30); LFP(31);
131 save_fpu(struct thread *td)
139 * Temporarily re-enable floating-point during the save
142 if (pcb->pcb_flags & PCB_VSX)
143 mtmsr(msr | PSL_FP | PSL_VSX);
149 * Save the floating-point registers and FPSCR to the PCB
151 if (pcb->pcb_flags & PCB_VSX) {
152 #define SFP(n) __asm ("stxvw4x " #n ", 0,%0" \
153 :: "b"(&pcb->pcb_fpu.fpr[n]));
154 SFP(0); SFP(1); SFP(2); SFP(3);
155 SFP(4); SFP(5); SFP(6); SFP(7);
156 SFP(8); SFP(9); SFP(10); SFP(11);
157 SFP(12); SFP(13); SFP(14); SFP(15);
158 SFP(16); SFP(17); SFP(18); SFP(19);
159 SFP(20); SFP(21); SFP(22); SFP(23);
160 SFP(24); SFP(25); SFP(26); SFP(27);
161 SFP(28); SFP(29); SFP(30); SFP(31);
164 #define SFP(n) __asm ("stfd " #n ", 0(%0)" \
165 :: "b"(&pcb->pcb_fpu.fpr[n]));
166 SFP(0); SFP(1); SFP(2); SFP(3);
167 SFP(4); SFP(5); SFP(6); SFP(7);
168 SFP(8); SFP(9); SFP(10); SFP(11);
169 SFP(12); SFP(13); SFP(14); SFP(15);
170 SFP(16); SFP(17); SFP(18); SFP(19);
171 SFP(20); SFP(21); SFP(22); SFP(23);
172 SFP(24); SFP(25); SFP(26); SFP(27);
173 SFP(28); SFP(29); SFP(30); SFP(31);
176 __asm __volatile ("mffs 0; stfd 0,0(%0)" :: "b"(&pcb->pcb_fpu.fpscr));
179 * Disable floating-point again
185 * Clear the current fp thread and pcb's CPU id
186 * XXX should this be left clear to allow lazy save/restore ?
188 pcb->pcb_fpcpu = INT_MAX;
189 PCPU_SET(fputhread, NULL);