altivec.c revision 1.4.2.4 1 /* $NetBSD: altivec.c,v 1.4.2.4 2005/03/04 16:39:02 skrll 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 1.4.2.4 2005/03/04 16:39:02 skrll 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 pcb->pcb_flags |= PCB_OWNALTIVEC;
115 __asm __volatile ("sync");
116
117 /*
118 * Restore MSR (turn off AltiVec)
119 */
120 mtmsr(msr);
121 }
122
123 void
124 save_vec_cpu(void)
125 {
126 struct cpu_info *ci = curcpu();
127 struct lwp *l;
128 struct pcb *pcb;
129 struct vreg *vr;
130 struct trapframe *tf;
131 register_t msr;
132
133 /*
134 * Turn on AltiVEC, turn off interrupts.
135 */
136 msr = mfmsr();
137 mtmsr((msr & ~PSL_EE) | PSL_VEC);
138 __asm __volatile ("isync");
139 l = ci->ci_veclwp;
140 if (l == NULL)
141 goto out;
142 pcb = &l->l_addr->u_pcb;
143 vr = &pcb->pcb_vr;
144 tf = trapframe(l);
145
146 #define STVX(n,vr) __asm /*__volatile*/("stvx %2,%0,%1" \
147 :: "b"(vr), "r"(offsetof(struct vreg, vreg[n])), "n"(n));
148
149 /*
150 * Save the vector registers.
151 */
152 STVX( 0,vr); STVX( 1,vr); STVX( 2,vr); STVX( 3,vr);
153 STVX( 4,vr); STVX( 5,vr); STVX( 6,vr); STVX( 7,vr);
154 STVX( 8,vr); STVX( 9,vr); STVX(10,vr); STVX(11,vr);
155 STVX(12,vr); STVX(13,vr); STVX(14,vr); STVX(15,vr);
156
157 STVX(16,vr); STVX(17,vr); STVX(18,vr); STVX(19,vr);
158 STVX(20,vr); STVX(21,vr); STVX(22,vr); STVX(23,vr);
159 STVX(24,vr); STVX(25,vr); STVX(26,vr); STVX(27,vr);
160 STVX(28,vr); STVX(29,vr); STVX(30,vr); STVX(31,vr);
161
162 /*
163 * Save VSCR (this needs to be done after save the vector registers
164 * since we need to use one as scratch).
165 */
166 __asm __volatile("mfvscr %2; stvewx %2,%0,%1" \
167 :: "b"(vr), "r"(offsetof(struct vreg, vscr)), "n"(0));
168
169 /*
170 * Save VRSAVE
171 */
172 vr->vrsave = tf->tf_xtra[TF_VRSAVE];
173
174 /*
175 * Note that we aren't using any CPU resources and stop any
176 * data streams.
177 */
178 pcb->pcb_veccpu = NULL;
179 ci->ci_veclwp = NULL;
180 __asm __volatile ("dssall; sync");
181
182 out:
183
184 /*
185 * Restore MSR (turn off AltiVec)
186 */
187 mtmsr(msr);
188 }
189
190 /*
191 * Save a process's AltiVEC state to its PCB. The state may be in any CPU.
192 * The process must either be curproc or traced by curproc (and stopped).
193 * (The point being that the process must not run on another CPU during
194 * this function).
195 */
196 void
197 save_vec_lwp(struct lwp *l, int discard)
198 {
199 struct pcb * const pcb = &l->l_addr->u_pcb;
200 struct cpu_info * const ci = curcpu();
201
202 /*
203 * If it's already in the PCB, there's nothing to do.
204 */
205 if (pcb->pcb_veccpu == NULL)
206 return;
207
208 /*
209 * If we simply need to discard the information, then don't
210 * to save anything.
211 */
212 if (discard) {
213 #ifndef MULTIPROCESSOR
214 KASSERT(ci == pcb->pcb_veccpu);
215 #endif
216 KASSERT(l == pcb->pcb_veccpu->ci_veclwp);
217 pcb->pcb_veccpu->ci_veclwp = NULL;
218 pcb->pcb_veccpu = NULL;
219 pcb->pcb_flags &= ~PCB_OWNALTIVEC;
220 return;
221 }
222
223 /*
224 * If the state is in the current CPU, just flush the current CPU's
225 * state.
226 */
227 if (l == ci->ci_veclwp) {
228 save_vec_cpu();
229 return;
230 }
231
232
233 #ifdef MULTIPROCESSOR
234 /*
235 * It must be on another CPU, flush it from there.
236 */
237
238 mp_save_vec_lwp(l);
239 #endif
240 }
241
242 #define ZERO_VEC 19
243
244 void
245 vzeropage(paddr_t pa)
246 {
247 const paddr_t ea = pa + PAGE_SIZE;
248 uint32_t vec[7], *vp = (void *) roundup((uintptr_t) vec, 16);
249 register_t omsr, msr;
250
251 __asm __volatile("mfmsr %0" : "=r"(omsr) :);
252
253 /*
254 * Turn on AltiVec, turn off interrupts.
255 */
256 msr = (omsr & ~PSL_EE) | PSL_VEC;
257 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
258
259 /*
260 * Save the VEC register we are going to use before we disable
261 * relocation.
262 */
263 __asm("stvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
264 __asm("vxor %0,%0,%0" :: "n"(ZERO_VEC));
265
266 /*
267 * Turn off data relocation (DMMU off).
268 */
269 msr &= ~PSL_DR;
270 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
271
272 /*
273 * Zero the page using a single cache line.
274 */
275 do {
276 __asm("stvx %2,%0,%1" :: "b"(pa), "r"( 0), "n"(ZERO_VEC));
277 __asm("stvxl %2,%0,%1" :: "b"(pa), "r"(16), "n"(ZERO_VEC));
278 __asm("stvx %2,%0,%1" :: "b"(pa), "r"(32), "n"(ZERO_VEC));
279 __asm("stvxl %2,%0,%1" :: "b"(pa), "r"(48), "n"(ZERO_VEC));
280 pa += 64;
281 } while (pa < ea);
282
283 /*
284 * Restore data relocation (DMMU on);
285 */
286 msr |= PSL_DR;
287 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
288
289 /*
290 * Restore VEC register (now that we can access the stack again).
291 */
292 __asm("lvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
293
294 /*
295 * Restore old MSR (AltiVec OFF).
296 */
297 __asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
298 }
299
300 #define LO_VEC 16
301 #define HI_VEC 17
302
303 void
304 vcopypage(paddr_t dst, paddr_t src)
305 {
306 const paddr_t edst = dst + PAGE_SIZE;
307 uint32_t vec[11], *vp = (void *) roundup((uintptr_t) vec, 16);
308 register_t omsr, msr;
309
310 __asm __volatile("mfmsr %0" : "=r"(omsr) :);
311
312 /*
313 * Turn on AltiVec, turn off interrupts.
314 */
315 msr = (omsr & ~PSL_EE) | PSL_VEC;
316 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
317
318 /*
319 * Save the VEC registers we will be using before we disable
320 * relocation.
321 */
322 __asm("stvx %2,%1,%0" :: "b"(vp), "r"( 0), "n"(LO_VEC));
323 __asm("stvx %2,%1,%0" :: "b"(vp), "r"(16), "n"(HI_VEC));
324
325 /*
326 * Turn off data relocation (DMMU off).
327 */
328 msr &= ~PSL_DR;
329 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
330
331 /*
332 * Copy the page using a single cache line. On most PPCs, two
333 * vector registers occupy one cache line.
334 */
335 do {
336 __asm("lvx %2,%0,%1" :: "b"(src), "r"( 0), "n"(LO_VEC));
337 __asm("stvx %2,%0,%1" :: "b"(dst), "r"( 0), "n"(LO_VEC));
338 __asm("lvxl %2,%0,%1" :: "b"(src), "r"(16), "n"(HI_VEC));
339 __asm("stvxl %2,%0,%1" :: "b"(dst), "r"(16), "n"(HI_VEC));
340 src += 32;
341 dst += 32;
342 } while (dst < edst);
343
344 /*
345 * Restore data relocation (DMMU on);
346 */
347 msr |= PSL_DR;
348 __asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
349
350 /*
351 * Restore VEC registers (now that we can access the stack again).
352 */
353 __asm("lvx %2,%1,%0" :: "b"(vp), "r"( 0), "n"(LO_VEC));
354 __asm("lvx %2,%1,%0" :: "b"(vp), "r"(16), "n"(HI_VEC));
355
356 /*
357 * Restore old MSR (AltiVec OFF).
358 */
359 __asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
360 }
361