altivec.c revision 1.7 1 /* $NetBSD: altivec.c,v 1.7 2004/04/16 23:58:08 matt Exp $ */
2
3 /*
4 * Copyright (C) 1996 Wolfgang Solfrank.
5 * Copyright (C) 1996 TooLs GmbH.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
21 *
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.
32 */
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: altivec.c,v 1.7 2004/04/16 23:58:08 matt Exp $");
36
37 #include "opt_multiprocessor.h"
38
39 #include <sys/param.h>
40 #include <sys/proc.h>
41 #include <sys/sa.h>
42 #include <sys/systm.h>
43 #include <sys/user.h>
44 #include <sys/malloc.h>
45 #include <sys/pool.h>
46
47 #include <uvm/uvm_extern.h>
48
49 #include <powerpc/altivec.h>
50 #include <powerpc/spr.h>
51 #include <powerpc/psl.h>
52
53 void
54 enable_vec(void)
55 {
56 struct cpu_info *ci = curcpu();
57 struct lwp *l = curlwp;
58 struct pcb *pcb = &l->l_addr->u_pcb;
59 struct trapframe *tf = trapframe(l);
60 struct vreg *vr = &pcb->pcb_vr;
61 register_t msr;
62
63 KASSERT(pcb->pcb_veccpu == NULL);
64
65 pcb->pcb_flags |= PCB_ALTIVEC;
66
67 /*
68 * Enable AltiVec temporarily (and disable interrupts).
69 */
70 msr = mfmsr();
71 mtmsr((msr & ~PSL_EE) | PSL_VEC);
72 __asm __volatile ("isync");
73 if (ci->ci_veclwp) {
74 save_vec_cpu();
75 }
76 KASSERT(curcpu()->ci_veclwp == NULL);
77
78 /*
79 * Restore VSCR by first loading it into a vector and then into VSCR.
80 * (this needs to done before loading the user's vector registers
81 * since we need to use a scratch vector register)
82 */
83 __asm __volatile("vxor %2,%2,%2; lvewx %2,%0,%1; mtvscr %2" \
84 :: "b"(vr), "r"(offsetof(struct vreg, vscr)), "n"(0));
85
86 /*
87 * VRSAVE will be restored when trap frame returns
88 */
89 tf->tf_xtra[TF_VRSAVE] = vr->vrsave;
90
91 #define LVX(n,vr) __asm /*__volatile*/("lvx %2,%0,%1" \
92 :: "b"(vr), "r"(offsetof(struct vreg, vreg[n])), "n"(n));
93
94 /*
95 * Load all 32 vector registers
96 */
97 LVX( 0,vr); LVX( 1,vr); LVX( 2,vr); LVX( 3,vr);
98 LVX( 4,vr); LVX( 5,vr); LVX( 6,vr); LVX( 7,vr);
99 LVX( 8,vr); LVX( 9,vr); LVX(10,vr); LVX(11,vr);
100 LVX(12,vr); LVX(13,vr); LVX(14,vr); LVX(15,vr);
101
102 LVX(16,vr); LVX(17,vr); LVX(18,vr); LVX(19,vr);
103 LVX(20,vr); LVX(21,vr); LVX(22,vr); LVX(23,vr);
104 LVX(24,vr); LVX(25,vr); LVX(26,vr); LVX(27,vr);
105 LVX(28,vr); LVX(29,vr); LVX(30,vr); LVX(31,vr);
106 __asm __volatile ("isync");
107
108 /*
109 * Enable AltiVec when we return to user-mode.
110 * Record the new ownership of the AltiVec unit.
111 */
112 curcpu()->ci_veclwp = l;
113 pcb->pcb_veccpu = curcpu();
114 __asm __volatile ("sync");
115
116 /*
117 * Restore MSR (turn off AltiVec)
118 */
119 mtmsr(msr);
120 }
121
122 void
123 save_vec_cpu(void)
124 {
125 struct cpu_info *ci = curcpu();
126 struct lwp *l;
127 struct pcb *pcb;
128 struct vreg *vr;
129 struct trapframe *tf;
130 register_t msr;
131
132 /*
133 * Turn on AltiVEC, turn off interrupts.
134 */
135 msr = mfmsr();
136 mtmsr((msr & ~PSL_EE) | PSL_VEC);
137 __asm __volatile ("isync");
138 l = ci->ci_veclwp;
139 if (l == NULL)
140 goto out;
141 pcb = &l->l_addr->u_pcb;
142 vr = &pcb->pcb_vr;
143 tf = trapframe(l);
144
145 #define STVX(n,vr) __asm /*__volatile*/("stvx %2,%0,%1" \
146 :: "b"(vr), "r"(offsetof(struct vreg, vreg[n])), "n"(n));
147
148 /*
149 * Save the vector registers.
150 */
151 STVX( 0,vr); STVX( 1,vr); STVX( 2,vr); STVX( 3,vr);
152 STVX( 4,vr); STVX( 5,vr); STVX( 6,vr); STVX( 7,vr);
153 STVX( 8,vr); STVX( 9,vr); STVX(10,vr); STVX(11,vr);
154 STVX(12,vr); STVX(13,vr); STVX(14,vr); STVX(15,vr);
155
156 STVX(16,vr); STVX(17,vr); STVX(18,vr); STVX(19,vr);
157 STVX(20,vr); STVX(21,vr); STVX(22,vr); STVX(23,vr);
158 STVX(24,vr); STVX(25,vr); STVX(26,vr); STVX(27,vr);
159 STVX(28,vr); STVX(29,vr); STVX(30,vr); STVX(31,vr);
160
161 /*
162 * Save VSCR (this needs to be done after save the vector registers
163 * since we need to use one as scratch).
164 */
165 __asm __volatile("mfvscr %2; stvewx %2,%0,%1" \
166 :: "b"(vr), "r"(offsetof(struct vreg, vscr)), "n"(0));
167
168 /*
169 * Save VRSAVE
170 */
171 vr->vrsave = tf->tf_xtra[TF_VRSAVE];
172
173 /*
174 * Note that we aren't using any CPU resources and stop any
175 * data streams.
176 */
177 pcb->pcb_veccpu = NULL;
178 ci->ci_veclwp = NULL;
179 __asm __volatile ("dssall; sync");
180
181 out:
182
183 /*
184 * Restore MSR (turn off AltiVec)
185 */
186 mtmsr(msr);
187 }
188
189 /*
190 * Save a process's AltiVEC state to its PCB. The state may be in any CPU.
191 * The process must either be curproc or traced by curproc (and stopped).
192 * (The point being that the process must not run on another CPU during
193 * this function).
194 */
195 void
196 save_vec_lwp(struct lwp *l, int discard)
197 {
198 struct pcb * const pcb = &l->l_addr->u_pcb;
199 struct cpu_info * const ci = curcpu();
200
201 /*
202 * If it's already in the PCB, there's nothing to do.
203 */
204 if (pcb->pcb_veccpu == NULL)
205 return;
206
207 /*
208 * If we simply need to discard the information, then don't
209 * to save anything.
210 */
211 if (discard) {
212 #ifndef MULTIPROCESSOR
213 KASSERT(ci == pcb->pcb_veccpu);
214 #endif
215 KASSERT(l == pcb->pcb_veccpu->ci_veclwp);
216 pcb->pcb_veccpu->ci_veclwp = NULL;
217 pcb->pcb_veccpu = NULL;
218 pcb->pcb_flags &= ~PCB_ALTIVEC;
219 return;
220 }
221
222 /*
223 * If the state is in the current CPU, just flush the current CPU's
224 * state.
225 */
226 if (l == ci->ci_veclwp) {
227 save_vec_cpu();
228 return;
229 }
230
231
232 #ifdef MULTIPROCESSOR
233 /*
234 * It must be on another CPU, flush it from there.
235 */
236
237 mp_save_vec_lwp(l);
238 #endif
239 }
240
241 #define ZERO_VEC 19
242
243 void
244 vzeropage(paddr_t pa)
245 {
246 const paddr_t ea = pa + PAGE_SIZE;
247 uint32_t vec[7], *vp = (void *) roundup((uintptr_t) vec, 16);
248 register_t omsr, msr;
249
250 __asm __volatile("mfmsr %0" : "=r"(omsr) :);
251
252 /*
253 * Turn on AltiVec, turn off interrupts.
254 */
255 msr = (omsr & ~PSL_EE) | PSL_VEC;
256 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
257
258 /*
259 * Save the VEC register we are going to use before we disable
260 * relocation.
261 */
262 __asm("stvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
263 __asm("vxor %0,%0,%0" :: "n"(ZERO_VEC));
264
265 /*
266 * Turn off data relocation (DMMU off).
267 */
268 msr &= ~PSL_DR;
269 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
270
271 /*
272 * Zero the page using a single cache line.
273 */
274 do {
275 __asm("stvx %2,%0,%1" :: "b"(pa), "r"( 0), "n"(ZERO_VEC));
276 __asm("stvxl %2,%0,%1" :: "b"(pa), "r"(16), "n"(ZERO_VEC));
277 __asm("stvx %2,%0,%1" :: "b"(pa), "r"(32), "n"(ZERO_VEC));
278 __asm("stvxl %2,%0,%1" :: "b"(pa), "r"(48), "n"(ZERO_VEC));
279 pa += 64;
280 } while (pa < ea);
281
282 /*
283 * Restore data relocation (DMMU on);
284 */
285 msr |= PSL_DR;
286 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
287
288 /*
289 * Restore VEC register (now that we can access the stack again).
290 */
291 __asm("lvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
292
293 /*
294 * Restore old MSR (AltiVec OFF).
295 */
296 __asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
297 }
298
299 #define LO_VEC 16
300 #define HI_VEC 17
301
302 void
303 vcopypage(paddr_t dst, paddr_t src)
304 {
305 const paddr_t edst = dst + PAGE_SIZE;
306 uint32_t vec[11], *vp = (void *) roundup((uintptr_t) vec, 16);
307 register_t omsr, msr;
308
309 __asm __volatile("mfmsr %0" : "=r"(omsr) :);
310
311 /*
312 * Turn on AltiVec, turn off interrupts.
313 */
314 msr = (omsr & ~PSL_EE) | PSL_VEC;
315 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
316
317 /*
318 * Save the VEC registers we will be using before we disable
319 * relocation.
320 */
321 __asm("stvx %2,%1,%0" :: "b"(vp), "r"( 0), "n"(LO_VEC));
322 __asm("stvx %2,%1,%0" :: "b"(vp), "r"(16), "n"(HI_VEC));
323
324 /*
325 * Turn off data relocation (DMMU off).
326 */
327 msr &= ~PSL_DR;
328 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
329
330 /*
331 * Copy the page using a single cache line. On most PPCs, two
332 * vector registers occupy one cache line.
333 */
334 do {
335 __asm("lvx %2,%0,%1" :: "b"(src), "r"( 0), "n"(LO_VEC));
336 __asm("stvx %2,%0,%1" :: "b"(dst), "r"( 0), "n"(LO_VEC));
337 __asm("lvxl %2,%0,%1" :: "b"(src), "r"(16), "n"(HI_VEC));
338 __asm("stvxl %2,%0,%1" :: "b"(dst), "r"(16), "n"(HI_VEC));
339 src += 32;
340 dst += 32;
341 } while (dst < edst);
342
343 /*
344 * Restore data relocation (DMMU on);
345 */
346 msr |= PSL_DR;
347 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
348
349 /*
350 * Restore VEC registers (now that we can access the stack again).
351 */
352 __asm("lvx %2,%1,%0" :: "b"(vp), "r"( 0), "n"(LO_VEC));
353 __asm("lvx %2,%1,%0" :: "b"(vp), "r"(16), "n"(HI_VEC));
354
355 /*
356 * Restore old MSR (AltiVec OFF).
357 */
358 __asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
359 }
360