xref: /netbsd-src/sys/arch/powerpc/oea/altivec.c (revision b8c616269f5ebf18ab2e35cb8099d683130a177c)
1 /*	$NetBSD: altivec.c,v 1.1 2003/02/03 17:10:09 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 #include <sys/param.h>
34 #include <sys/proc.h>
35 #include <sys/sa.h>
36 #include <sys/systm.h>
37 #include <sys/user.h>
38 #include <sys/malloc.h>
39 #include <sys/pool.h>
40 
41 #include <powerpc/altivec.h>
42 #include <powerpc/spr.h>
43 #include <powerpc/psl.h>
44 
45 struct pool vecpool;
46 
47 void
48 enable_vec()
49 {
50 	struct cpu_info *ci = curcpu();
51 	struct lwp *l = curlwp;
52 	struct pcb *pcb = &l->l_addr->u_pcb;
53 	struct trapframe *tf = trapframe(l);
54 	struct vreg *vr = pcb->pcb_vr;
55 	int msr, scratch;
56 
57 	KASSERT(pcb->pcb_veccpu == NULL);
58 
59 	/*
60 	 * Allocate a vreg structure if we haven't done so.
61 	 */
62 	if (!(pcb->pcb_flags & PCB_ALTIVEC)) {
63 		vr = pcb->pcb_vr = pool_get(&vecpool, PR_WAITOK);
64 		pcb->pcb_flags |= PCB_ALTIVEC;
65 
66 		/*
67 		 * Initialize the vectors with NaNs
68 		 */
69 
70 		for (scratch = 0; scratch < 32; scratch++) {
71 			vr->vreg[scratch][0] = 0x7FFFDEAD;
72 			vr->vreg[scratch][1] = 0x7FFFDEAD;
73 			vr->vreg[scratch][2] = 0x7FFFDEAD;
74 			vr->vreg[scratch][3] = 0x7FFFDEAD;
75 		}
76 		vr->vscr = 0;
77 		vr->vrsave = tf->tf_xtra[TF_VRSAVE];
78 	}
79 
80 	/*
81 	 * Enable AltiVec temporarily (and disable interrupts).
82 	 */
83 	msr = mfmsr();
84 	mtmsr((msr & ~PSL_EE) | PSL_VEC);
85 	__asm __volatile ("isync");
86 	if (ci->ci_veclwp) {
87 		save_vec_cpu();
88 	}
89 	KASSERT(curcpu()->ci_veclwp == NULL);
90 
91 	/*
92 	 * Restore VSCR by first loading it into a vector and then into VSCR.
93 	 * (this needs to done before loading the user's vector registers
94 	 * since we need to use a scratch vector register)
95 	 */
96 	__asm __volatile("vxor %2,%2,%2; lvewx %2,%0,%1; mtvscr %2" \
97 	    ::	"r"(vr), "r"(offsetof(struct vreg, vscr)), "n"(0));
98 
99 	/*
100 	 * VRSAVE will be restored when trap frame returns
101 	 */
102 	tf->tf_xtra[TF_VRSAVE] = vr->vrsave;
103 
104 #define	LVX(n,vr)	__asm /*__volatile*/("lvx %2,%0,%1" \
105 	    ::	"r"(vr), "r"(offsetof(struct vreg, vreg[n])), "n"(n));
106 
107 	/*
108 	 * Load all 32 vector registers
109 	 */
110 	LVX( 0,vr);	LVX( 1,vr);	LVX( 2,vr);	LVX( 3,vr);
111 	LVX( 4,vr);	LVX( 5,vr);	LVX( 6,vr);	LVX( 7,vr);
112 	LVX( 8,vr);	LVX( 9,vr);	LVX(10,vr);	LVX(11,vr);
113 	LVX(12,vr);	LVX(13,vr);	LVX(14,vr);	LVX(15,vr);
114 
115 	LVX(16,vr);	LVX(17,vr);	LVX(18,vr);	LVX(19,vr);
116 	LVX(20,vr);	LVX(21,vr);	LVX(22,vr);	LVX(23,vr);
117 	LVX(24,vr);	LVX(25,vr);	LVX(26,vr);	LVX(27,vr);
118 	LVX(28,vr);	LVX(29,vr);	LVX(30,vr);	LVX(31,vr);
119 	__asm __volatile ("isync");
120 
121 	/*
122 	 * Enable AltiVec when we return to user-mode.
123 	 * Record the new ownership of the AltiVec unit.
124 	 */
125 	tf->srr1 |= PSL_VEC;
126 	curcpu()->ci_veclwp = l;
127 	pcb->pcb_veccpu = curcpu();
128 	__asm __volatile ("sync");
129 
130 	/*
131 	 * Restore MSR (turn off AltiVec)
132 	 */
133 	mtmsr(msr);
134 }
135 
136 void
137 save_vec_cpu(void)
138 {
139 	struct cpu_info *ci = curcpu();
140 	struct lwp *l;
141 	struct pcb *pcb;
142 	struct vreg *vr;
143 	struct trapframe *tf;
144 	int msr;
145 
146 	/*
147 	 * Turn on AltiVEC, turn off interrupts.
148 	 */
149 	msr = mfmsr();
150 	mtmsr((msr & ~PSL_EE) | PSL_VEC);
151 	__asm __volatile ("isync");
152 	l = ci->ci_veclwp;
153 	if (l == NULL) {
154 		goto out;
155 	}
156 	pcb = &l->l_addr->u_pcb;
157 	vr = pcb->pcb_vr;
158 	tf = trapframe(l);
159 
160 #define	STVX(n,vr)	__asm /*__volatile*/("stvx %2,%0,%1" \
161 	    ::	"r"(vr), "r"(offsetof(struct vreg, vreg[n])), "n"(n));
162 
163 	/*
164 	 * Save the vector registers.
165 	 */
166 	STVX( 0,vr);	STVX( 1,vr);	STVX( 2,vr);	STVX( 3,vr);
167 	STVX( 4,vr);	STVX( 5,vr);	STVX( 6,vr);	STVX( 7,vr);
168 	STVX( 8,vr);	STVX( 9,vr);	STVX(10,vr);	STVX(11,vr);
169 	STVX(12,vr);	STVX(13,vr);	STVX(14,vr);	STVX(15,vr);
170 
171 	STVX(16,vr);	STVX(17,vr);	STVX(18,vr);	STVX(19,vr);
172 	STVX(20,vr);	STVX(21,vr);	STVX(22,vr);	STVX(23,vr);
173 	STVX(24,vr);	STVX(25,vr);	STVX(26,vr);	STVX(27,vr);
174 	STVX(28,vr);	STVX(29,vr);	STVX(30,vr);	STVX(31,vr);
175 
176 	/*
177 	 * Save VSCR (this needs to be done after save the vector registers
178 	 * since we need to use one as scratch).
179 	 */
180 	__asm __volatile("mfvscr %2; stvewx %2,%0,%1" \
181 	    ::	"r"(vr), "r"(offsetof(struct vreg, vscr)), "n"(0));
182 
183 	/*
184 	 * Save VRSAVE
185 	 */
186 	vr->vrsave = tf->tf_xtra[TF_VRSAVE];
187 
188 	/*
189 	 * Note that we aren't using any CPU resources and stop any
190 	 * data streams.
191 	 */
192 	tf->srr1 &= ~PSL_VEC;
193 	pcb->pcb_veccpu = NULL;
194 	ci->ci_veclwp = NULL;
195 	__asm __volatile ("dssall; sync");
196 
197  out:
198 
199 	/*
200 	 * Restore MSR (turn off AltiVec)
201 	 */
202 	mtmsr(msr);
203 }
204 
205 /*
206  * Save a process's AltiVEC state to its PCB.  The state may be in any CPU.
207  * The process must either be curproc or traced by curproc (and stopped).
208  * (The point being that the process must not run on another CPU during
209  * this function).
210  */
211 void
212 save_vec_lwp(l)
213 	struct lwp *l;
214 {
215 	struct pcb *pcb = &l->l_addr->u_pcb;
216 	struct cpu_info *ci = curcpu();
217 
218 	/*
219 	 * If it's already in the PCB, there's nothing to do.
220 	 */
221 
222 	if (pcb->pcb_veccpu == NULL) {
223 		return;
224 	}
225 
226 	/*
227 	 * If the state is in the current CPU, just flush the current CPU's
228 	 * state.
229 	 */
230 
231 	if (l == ci->ci_veclwp) {
232 		save_vec_cpu();
233 		return;
234 	}
235 
236 #ifdef MULTIPROCESSOR
237 
238 	/*
239 	 * It must be on another CPU, flush it from there.
240 	 */
241 
242 	mp_save_vec_lwp(l);
243 #endif
244 }
245 
246 #define ZERO_VEC	19
247 
248 void
249 vzeropage(paddr_t pa)
250 {
251 	const paddr_t ea = pa + NBPG;
252 	uint32_t vec[7], *vp = (void *) roundup((uintptr_t) vec, 16);
253 	uint32_t omsr, msr;
254 
255 	__asm __volatile("mfmsr %0" : "=r"(omsr) :);
256 
257 	/*
258 	 * Turn on AltiVec, turn off interrupts.
259 	 */
260 	msr = (omsr & ~PSL_EE) | PSL_VEC;
261 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
262 
263 	/*
264 	 * Save the VEC register we are going to use before we disable
265 	 * relocation.
266 	 */
267 	__asm("stvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
268 	__asm("vxor %0,%0,%0" :: "n"(ZERO_VEC));
269 
270 	/*
271 	 * Turn off data relocation (DMMU off).
272 	 */
273 	msr &= ~PSL_DR;
274 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
275 
276 	/*
277 	 * Zero the page using a single cache line.
278 	 */
279 	do {
280 		__asm("stvx %2,%0,%1" ::  "r"(pa), "r"( 0), "n"(ZERO_VEC));
281 		__asm("stvxl %2,%0,%1" :: "r"(pa), "r"(16), "n"(ZERO_VEC));
282 		__asm("stvx %2,%0,%1" ::  "r"(pa), "r"(32), "n"(ZERO_VEC));
283 		__asm("stvxl %2,%0,%1" :: "r"(pa), "r"(48), "n"(ZERO_VEC));
284 		pa += 64;
285 	} while (pa < ea);
286 
287 	/*
288 	 * Restore data relocation (DMMU on);
289 	 */
290 	msr |= PSL_DR;
291 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
292 
293 	/*
294 	 * Restore VEC register (now that we can access the stack again).
295 	 */
296 	__asm("lvx %1,0,%0" :: "r"(vp), "n"(ZERO_VEC));
297 
298 	/*
299 	 * Restore old MSR (AltiVec OFF).
300 	 */
301 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
302 }
303 
304 #define LO_VEC	16
305 #define HI_VEC	17
306 
307 void
308 vcopypage(paddr_t dst, paddr_t src)
309 {
310 	const paddr_t edst = dst + NBPG;
311 	uint32_t vec[11], *vp = (void *) roundup((uintptr_t) vec, 16);
312 	uint32_t omsr, msr;
313 
314 	__asm __volatile("mfmsr %0" : "=r"(omsr) :);
315 
316 	/*
317 	 * Turn on AltiVec, turn off interrupts.
318 	 */
319 	msr = (omsr & ~PSL_EE) | PSL_VEC;
320 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
321 
322 	/*
323 	 * Save the VEC registers we will be using before we disable
324 	 * relocation.
325 	 */
326 	__asm("stvx %2,%1,%0" :: "r"(vp), "r"( 0), "n"(LO_VEC));
327 	__asm("stvx %2,%1,%0" :: "r"(vp), "r"(16), "n"(HI_VEC));
328 
329 	/*
330 	 * Turn off data relocation (DMMU off).
331 	 */
332 	msr &= ~PSL_DR;
333 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
334 
335 	/*
336 	 * Copy the page using a single cache line.  On most PPCs, two
337 	 * vector registers occupy one cache line.
338 	 */
339 	do {
340 		__asm("lvx %2,%0,%1"   :: "r"(src), "r"( 0), "n"(LO_VEC));
341 		__asm("stvx %2,%0,%1"  :: "r"(dst), "r"( 0), "n"(LO_VEC));
342 		__asm("lvxl %2,%0,%1"  :: "r"(src), "r"(16), "n"(HI_VEC));
343 		__asm("stvxl %2,%0,%1" :: "r"(dst), "r"(16), "n"(HI_VEC));
344 		src += 32;
345 		dst += 32;
346 	} while (dst < edst);
347 
348 	/*
349 	 * Restore data relocation (DMMU on);
350 	 */
351 	msr |= PSL_DR;
352 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(msr));
353 
354 	/*
355 	 * Restore VEC registers (now that we can access the stack again).
356 	 */
357 	__asm("lvx %2,%1,%0" :: "r"(vp), "r"( 0), "n"(LO_VEC));
358 	__asm("lvx %2,%1,%0" :: "r"(vp), "r"(16), "n"(HI_VEC));
359 
360 	/*
361 	 * Restore old MSR (AltiVec OFF).
362 	 */
363 	__asm __volatile("sync; mtmsr %0; isync" :: "r"(omsr));
364 }
365 
366 void
367 init_vec(void)
368 {
369 	pool_init(&vecpool, sizeof(struct vreg), 16, 0, 0, "vecpl", NULL);
370 }
371