xref: /freebsd/sys/i386/i386/initcpu.c (revision 685dc743dc3b5645e34836464128e1c0558b404b)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) KATO Takenori, 1997, 1998.
5  *
6  * All rights reserved.  Unpublished rights reserved under the copyright
7  * laws of Japan.
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  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer as
15  *    the first lines of this file unmodified.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #include "opt_cpu.h"
34 
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/systm.h>
38 #include <sys/sysctl.h>
39 
40 #include <machine/cputypes.h>
41 #include <machine/md_var.h>
42 #include <machine/psl.h>
43 #include <machine/specialreg.h>
44 
45 #include <vm/vm.h>
46 #include <vm/pmap.h>
47 
48 #ifdef I486_CPU
49 static void init_5x86(void);
50 static void init_bluelightning(void);
51 static void init_486dlc(void);
52 static void init_cy486dx(void);
53 #ifdef CPU_I486_ON_386
54 static void init_i486_on_386(void);
55 #endif
56 static void init_6x86(void);
57 #endif /* I486_CPU */
58 
59 #if defined(I586_CPU) && defined(CPU_WT_ALLOC)
60 static void	enable_K5_wt_alloc(void);
61 static void	enable_K6_wt_alloc(void);
62 static void	enable_K6_2_wt_alloc(void);
63 #endif
64 
65 #ifdef I686_CPU
66 static void	init_6x86MX(void);
67 static void	init_ppro(void);
68 static void	init_mendocino(void);
69 #endif
70 
71 static int	hw_instruction_sse;
72 SYSCTL_INT(_hw, OID_AUTO, instruction_sse, CTLFLAG_RD,
73     &hw_instruction_sse, 0, "SIMD/MMX2 instructions available in CPU");
74 /*
75  * -1: automatic (default)
76  *  0: keep enable CLFLUSH
77  *  1: force disable CLFLUSH
78  */
79 static int	hw_clflush_disable = -1;
80 
81 u_int	cyrix_did;		/* Device ID of Cyrix CPU */
82 
83 #ifdef I486_CPU
84 /*
85  * IBM Blue Lightning
86  */
87 static void
init_bluelightning(void)88 init_bluelightning(void)
89 {
90 	register_t saveintr;
91 
92 	saveintr = intr_disable();
93 
94 	load_cr0(rcr0() | CR0_CD | CR0_NW);
95 	invd();
96 
97 #ifdef CPU_BLUELIGHTNING_FPU_OP_CACHE
98 	wrmsr(0x1000, 0x9c92LL);	/* FP operand can be cacheable on Cyrix FPU */
99 #else
100 	wrmsr(0x1000, 0x1c92LL);	/* Intel FPU */
101 #endif
102 	/* Enables 13MB and 0-640KB cache. */
103 	wrmsr(0x1001, (0xd0LL << 32) | 0x3ff);
104 #ifdef CPU_BLUELIGHTNING_3X
105 	wrmsr(0x1002, 0x04000000LL);	/* Enables triple-clock mode. */
106 #else
107 	wrmsr(0x1002, 0x03000000LL);	/* Enables double-clock mode. */
108 #endif
109 
110 	/* Enable caching in CR0. */
111 	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
112 	invd();
113 	intr_restore(saveintr);
114 }
115 
116 /*
117  * Cyrix 486SLC/DLC/SR/DR series
118  */
119 static void
init_486dlc(void)120 init_486dlc(void)
121 {
122 	register_t saveintr;
123 	u_char	ccr0;
124 
125 	saveintr = intr_disable();
126 	invd();
127 
128 	ccr0 = read_cyrix_reg(CCR0);
129 #ifndef CYRIX_CACHE_WORKS
130 	ccr0 |= CCR0_NC1 | CCR0_BARB;
131 	write_cyrix_reg(CCR0, ccr0);
132 	invd();
133 #else
134 	ccr0 &= ~CCR0_NC0;
135 #ifndef CYRIX_CACHE_REALLY_WORKS
136 	ccr0 |= CCR0_NC1 | CCR0_BARB;
137 #else
138 	ccr0 |= CCR0_NC1;
139 #endif
140 #ifdef CPU_DIRECT_MAPPED_CACHE
141 	ccr0 |= CCR0_CO;			/* Direct mapped mode. */
142 #endif
143 	write_cyrix_reg(CCR0, ccr0);
144 
145 	/* Clear non-cacheable region. */
146 	write_cyrix_reg(NCR1+2, NCR_SIZE_0K);
147 	write_cyrix_reg(NCR2+2, NCR_SIZE_0K);
148 	write_cyrix_reg(NCR3+2, NCR_SIZE_0K);
149 	write_cyrix_reg(NCR4+2, NCR_SIZE_0K);
150 
151 	write_cyrix_reg(0, 0);	/* dummy write */
152 
153 	/* Enable caching in CR0. */
154 	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
155 	invd();
156 #endif /* !CYRIX_CACHE_WORKS */
157 	intr_restore(saveintr);
158 }
159 
160 /*
161  * Cyrix 486S/DX series
162  */
163 static void
init_cy486dx(void)164 init_cy486dx(void)
165 {
166 	register_t saveintr;
167 	u_char	ccr2;
168 
169 	saveintr = intr_disable();
170 	invd();
171 
172 	ccr2 = read_cyrix_reg(CCR2);
173 #ifdef CPU_SUSP_HLT
174 	ccr2 |= CCR2_SUSP_HLT;
175 #endif
176 
177 	write_cyrix_reg(CCR2, ccr2);
178 	intr_restore(saveintr);
179 }
180 
181 /*
182  * Cyrix 5x86
183  */
184 static void
init_5x86(void)185 init_5x86(void)
186 {
187 	register_t saveintr;
188 	u_char	ccr2, ccr3, ccr4, pcr0;
189 
190 	saveintr = intr_disable();
191 
192 	load_cr0(rcr0() | CR0_CD | CR0_NW);
193 	wbinvd();
194 
195 	(void)read_cyrix_reg(CCR3);		/* dummy */
196 
197 	/* Initialize CCR2. */
198 	ccr2 = read_cyrix_reg(CCR2);
199 	ccr2 |= CCR2_WB;
200 #ifdef CPU_SUSP_HLT
201 	ccr2 |= CCR2_SUSP_HLT;
202 #else
203 	ccr2 &= ~CCR2_SUSP_HLT;
204 #endif
205 	ccr2 |= CCR2_WT1;
206 	write_cyrix_reg(CCR2, ccr2);
207 
208 	/* Initialize CCR4. */
209 	ccr3 = read_cyrix_reg(CCR3);
210 	write_cyrix_reg(CCR3, CCR3_MAPEN0);
211 
212 	ccr4 = read_cyrix_reg(CCR4);
213 	ccr4 |= CCR4_DTE;
214 	ccr4 |= CCR4_MEM;
215 #ifdef CPU_FASTER_5X86_FPU
216 	ccr4 |= CCR4_FASTFPE;
217 #else
218 	ccr4 &= ~CCR4_FASTFPE;
219 #endif
220 	ccr4 &= ~CCR4_IOMASK;
221 	/********************************************************************
222 	 * WARNING: The "BIOS Writers Guide" mentions that I/O recovery time
223 	 * should be 0 for errata fix.
224 	 ********************************************************************/
225 #ifdef CPU_IORT
226 	ccr4 |= CPU_IORT & CCR4_IOMASK;
227 #endif
228 	write_cyrix_reg(CCR4, ccr4);
229 
230 	/* Initialize PCR0. */
231 	/****************************************************************
232 	 * WARNING: RSTK_EN and LOOP_EN could make your system unstable.
233 	 * BTB_EN might make your system unstable.
234 	 ****************************************************************/
235 	pcr0 = read_cyrix_reg(PCR0);
236 #ifdef CPU_RSTK_EN
237 	pcr0 |= PCR0_RSTK;
238 #else
239 	pcr0 &= ~PCR0_RSTK;
240 #endif
241 #ifdef CPU_BTB_EN
242 	pcr0 |= PCR0_BTB;
243 #else
244 	pcr0 &= ~PCR0_BTB;
245 #endif
246 #ifdef CPU_LOOP_EN
247 	pcr0 |= PCR0_LOOP;
248 #else
249 	pcr0 &= ~PCR0_LOOP;
250 #endif
251 
252 	/****************************************************************
253 	 * WARNING: if you use a memory mapped I/O device, don't use
254 	 * DISABLE_5X86_LSSER option, which may reorder memory mapped
255 	 * I/O access.
256 	 * IF YOUR MOTHERBOARD HAS PCI BUS, DON'T DISABLE LSSER.
257 	 ****************************************************************/
258 #ifdef CPU_DISABLE_5X86_LSSER
259 	pcr0 &= ~PCR0_LSSER;
260 #else
261 	pcr0 |= PCR0_LSSER;
262 #endif
263 	write_cyrix_reg(PCR0, pcr0);
264 
265 	/* Restore CCR3. */
266 	write_cyrix_reg(CCR3, ccr3);
267 
268 	(void)read_cyrix_reg(0x80);		/* dummy */
269 
270 	/* Unlock NW bit in CR0. */
271 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
272 	load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0, NW = 1 */
273 	/* Lock NW bit in CR0. */
274 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
275 
276 	intr_restore(saveintr);
277 }
278 
279 #ifdef CPU_I486_ON_386
280 /*
281  * There are i486 based upgrade products for i386 machines.
282  * In this case, BIOS doesn't enable CPU cache.
283  */
284 static void
init_i486_on_386(void)285 init_i486_on_386(void)
286 {
287 	register_t saveintr;
288 
289 	saveintr = intr_disable();
290 
291 	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0, NW = 0 */
292 
293 	intr_restore(saveintr);
294 }
295 #endif
296 
297 /*
298  * Cyrix 6x86
299  *
300  * XXX - What should I do here?  Please let me know.
301  */
302 static void
init_6x86(void)303 init_6x86(void)
304 {
305 	register_t saveintr;
306 	u_char	ccr3, ccr4;
307 
308 	saveintr = intr_disable();
309 
310 	load_cr0(rcr0() | CR0_CD | CR0_NW);
311 	wbinvd();
312 
313 	/* Initialize CCR0. */
314 	write_cyrix_reg(CCR0, read_cyrix_reg(CCR0) | CCR0_NC1);
315 
316 	/* Initialize CCR1. */
317 #ifdef CPU_CYRIX_NO_LOCK
318 	write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) | CCR1_NO_LOCK);
319 #else
320 	write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) & ~CCR1_NO_LOCK);
321 #endif
322 
323 	/* Initialize CCR2. */
324 #ifdef CPU_SUSP_HLT
325 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_SUSP_HLT);
326 #else
327 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_SUSP_HLT);
328 #endif
329 
330 	ccr3 = read_cyrix_reg(CCR3);
331 	write_cyrix_reg(CCR3, CCR3_MAPEN0);
332 
333 	/* Initialize CCR4. */
334 	ccr4 = read_cyrix_reg(CCR4);
335 	ccr4 |= CCR4_DTE;
336 	ccr4 &= ~CCR4_IOMASK;
337 #ifdef CPU_IORT
338 	write_cyrix_reg(CCR4, ccr4 | (CPU_IORT & CCR4_IOMASK));
339 #else
340 	write_cyrix_reg(CCR4, ccr4 | 7);
341 #endif
342 
343 	/* Initialize CCR5. */
344 #ifdef CPU_WT_ALLOC
345 	write_cyrix_reg(CCR5, read_cyrix_reg(CCR5) | CCR5_WT_ALLOC);
346 #endif
347 
348 	/* Restore CCR3. */
349 	write_cyrix_reg(CCR3, ccr3);
350 
351 	/* Unlock NW bit in CR0. */
352 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
353 
354 	/*
355 	 * Earlier revision of the 6x86 CPU could crash the system if
356 	 * L1 cache is in write-back mode.
357 	 */
358 	if ((cyrix_did & 0xff00) > 0x1600)
359 		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
360 	else {
361 		/* Revision 2.6 and lower. */
362 #ifdef CYRIX_CACHE_REALLY_WORKS
363 		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
364 #else
365 		load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0 and NW = 1 */
366 #endif
367 	}
368 
369 	/* Lock NW bit in CR0. */
370 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
371 
372 	intr_restore(saveintr);
373 }
374 #endif /* I486_CPU */
375 
376 #ifdef I586_CPU
377 /*
378  * Rise mP6
379  */
380 static void
init_rise(void)381 init_rise(void)
382 {
383 
384 	/*
385 	 * The CMPXCHG8B instruction is always available but hidden.
386 	 */
387 	cpu_feature |= CPUID_CX8;
388 }
389 
390 /*
391  * IDT WinChip C6/2/2A/2B/3
392  *
393  * http://www.centtech.com/winchip_bios_writers_guide_v4_0.pdf
394  */
395 static void
init_winchip(void)396 init_winchip(void)
397 {
398 	u_int regs[4];
399 	uint64_t fcr;
400 
401 	fcr = rdmsr(0x0107);
402 
403 	/*
404 	 * Set ECX8, DSMC, DTLOCK/EDCTLB, EMMX, and ERETSTK and clear DPDC.
405 	 */
406 	fcr |= (1 << 1) | (1 << 7) | (1 << 8) | (1 << 9) | (1 << 16);
407 	fcr &= ~(1ULL << 11);
408 
409 	/*
410 	 * Additionally, set EBRPRED, E2MMX and EAMD3D for WinChip 2 and 3.
411 	 */
412 	if (CPUID_TO_MODEL(cpu_id) >= 8)
413 		fcr |= (1 << 12) | (1 << 19) | (1 << 20);
414 
415 	wrmsr(0x0107, fcr);
416 	do_cpuid(1, regs);
417 	cpu_feature = regs[3];
418 }
419 #endif
420 
421 #ifdef I686_CPU
422 /*
423  * Cyrix 6x86MX (code-named M2)
424  *
425  * XXX - What should I do here?  Please let me know.
426  */
427 static void
init_6x86MX(void)428 init_6x86MX(void)
429 {
430 	register_t saveintr;
431 	u_char	ccr3, ccr4;
432 
433 	saveintr = intr_disable();
434 
435 	load_cr0(rcr0() | CR0_CD | CR0_NW);
436 	wbinvd();
437 
438 	/* Initialize CCR0. */
439 	write_cyrix_reg(CCR0, read_cyrix_reg(CCR0) | CCR0_NC1);
440 
441 	/* Initialize CCR1. */
442 #ifdef CPU_CYRIX_NO_LOCK
443 	write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) | CCR1_NO_LOCK);
444 #else
445 	write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) & ~CCR1_NO_LOCK);
446 #endif
447 
448 	/* Initialize CCR2. */
449 #ifdef CPU_SUSP_HLT
450 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_SUSP_HLT);
451 #else
452 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_SUSP_HLT);
453 #endif
454 
455 	ccr3 = read_cyrix_reg(CCR3);
456 	write_cyrix_reg(CCR3, CCR3_MAPEN0);
457 
458 	/* Initialize CCR4. */
459 	ccr4 = read_cyrix_reg(CCR4);
460 	ccr4 &= ~CCR4_IOMASK;
461 #ifdef CPU_IORT
462 	write_cyrix_reg(CCR4, ccr4 | (CPU_IORT & CCR4_IOMASK));
463 #else
464 	write_cyrix_reg(CCR4, ccr4 | 7);
465 #endif
466 
467 	/* Initialize CCR5. */
468 #ifdef CPU_WT_ALLOC
469 	write_cyrix_reg(CCR5, read_cyrix_reg(CCR5) | CCR5_WT_ALLOC);
470 #endif
471 
472 	/* Restore CCR3. */
473 	write_cyrix_reg(CCR3, ccr3);
474 
475 	/* Unlock NW bit in CR0. */
476 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
477 
478 	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
479 
480 	/* Lock NW bit in CR0. */
481 	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
482 
483 	intr_restore(saveintr);
484 }
485 
486 static int ppro_apic_used = -1;
487 
488 static void
init_ppro(void)489 init_ppro(void)
490 {
491 	u_int64_t	apicbase;
492 
493 	/*
494 	 * Local APIC should be disabled if it is not going to be used.
495 	 */
496 	if (ppro_apic_used != 1) {
497 		apicbase = rdmsr(MSR_APICBASE);
498 		apicbase &= ~APICBASE_ENABLED;
499 		wrmsr(MSR_APICBASE, apicbase);
500 		ppro_apic_used = 0;
501 	}
502 }
503 
504 /*
505  * If the local APIC is going to be used after being disabled above,
506  * re-enable it and don't disable it in the future.
507  */
508 void
ppro_reenable_apic(void)509 ppro_reenable_apic(void)
510 {
511 	u_int64_t	apicbase;
512 
513 	if (ppro_apic_used == 0) {
514 		apicbase = rdmsr(MSR_APICBASE);
515 		apicbase |= APICBASE_ENABLED;
516 		wrmsr(MSR_APICBASE, apicbase);
517 		ppro_apic_used = 1;
518 	}
519 }
520 
521 /*
522  * Initialize BBL_CR_CTL3 (Control register 3: used to configure the
523  * L2 cache).
524  */
525 static void
init_mendocino(void)526 init_mendocino(void)
527 {
528 #ifdef CPU_PPRO2CELERON
529 	register_t	saveintr;
530 	u_int64_t	bbl_cr_ctl3;
531 
532 	saveintr = intr_disable();
533 
534 	load_cr0(rcr0() | CR0_CD | CR0_NW);
535 	wbinvd();
536 
537 	bbl_cr_ctl3 = rdmsr(MSR_BBL_CR_CTL3);
538 
539 	/* If the L2 cache is configured, do nothing. */
540 	if (!(bbl_cr_ctl3 & 1)) {
541 		bbl_cr_ctl3 = 0x134052bLL;
542 
543 		/* Set L2 Cache Latency (Default: 5). */
544 #ifdef	CPU_CELERON_L2_LATENCY
545 #if CPU_L2_LATENCY > 15
546 #error invalid CPU_L2_LATENCY.
547 #endif
548 		bbl_cr_ctl3 |= CPU_L2_LATENCY << 1;
549 #else
550 		bbl_cr_ctl3 |= 5 << 1;
551 #endif
552 		wrmsr(MSR_BBL_CR_CTL3, bbl_cr_ctl3);
553 	}
554 
555 	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));
556 	intr_restore(saveintr);
557 #endif /* CPU_PPRO2CELERON */
558 }
559 
560 /*
561  * Initialize special VIA features
562  */
563 static void
init_via(void)564 init_via(void)
565 {
566 	u_int regs[4], val;
567 	uint64_t fcr;
568 
569 	/*
570 	 * Explicitly enable CX8 and PGE on C3.
571 	 *
572 	 * http://www.via.com.tw/download/mainboards/6/13/VIA_C3_EBGA%20datasheet110.pdf
573 	 */
574 	if (CPUID_TO_MODEL(cpu_id) <= 9)
575 		fcr = (1 << 1) | (1 << 7);
576 	else
577 		fcr = 0;
578 
579 	/*
580 	 * Check extended CPUID for PadLock features.
581 	 *
582 	 * http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/programming_guide.pdf
583 	 */
584 	do_cpuid(0xc0000000, regs);
585 	if (regs[0] >= 0xc0000001) {
586 		do_cpuid(0xc0000001, regs);
587 		val = regs[3];
588 	} else
589 		val = 0;
590 
591 	/* Enable RNG if present. */
592 	if ((val & VIA_CPUID_HAS_RNG) != 0) {
593 		via_feature_rng = VIA_HAS_RNG;
594 		wrmsr(0x110B, rdmsr(0x110B) | VIA_CPUID_DO_RNG);
595 	}
596 
597 	/* Enable PadLock if present. */
598 	if ((val & VIA_CPUID_HAS_ACE) != 0)
599 		via_feature_xcrypt |= VIA_HAS_AES;
600 	if ((val & VIA_CPUID_HAS_ACE2) != 0)
601 		via_feature_xcrypt |= VIA_HAS_AESCTR;
602 	if ((val & VIA_CPUID_HAS_PHE) != 0)
603 		via_feature_xcrypt |= VIA_HAS_SHA;
604 	if ((val & VIA_CPUID_HAS_PMM) != 0)
605 		via_feature_xcrypt |= VIA_HAS_MM;
606 	if (via_feature_xcrypt != 0)
607 		fcr |= 1 << 28;
608 
609 	wrmsr(0x1107, rdmsr(0x1107) | fcr);
610 }
611 
612 #endif /* I686_CPU */
613 
614 #if defined(I586_CPU) || defined(I686_CPU)
615 static void
init_transmeta(void)616 init_transmeta(void)
617 {
618 	u_int regs[0];
619 
620 	/* Expose all hidden features. */
621 	wrmsr(0x80860004, rdmsr(0x80860004) | ~0UL);
622 	do_cpuid(1, regs);
623 	cpu_feature = regs[3];
624 }
625 #endif
626 
627 /*
628  * The value for the TSC_AUX MSR and rdtscp/rdpid on the invoking CPU.
629  *
630  * Caller should prevent CPU migration.
631  */
632 u_int
cpu_auxmsr(void)633 cpu_auxmsr(void)
634 {
635 	KASSERT((read_eflags() & PSL_I) == 0, ("context switch possible"));
636 	return (PCPU_GET(cpuid));
637 }
638 
639 extern int elf32_nxstack;
640 
641 void
initializecpu(void)642 initializecpu(void)
643 {
644 	uint64_t msr;
645 
646 	switch (cpu) {
647 #ifdef I486_CPU
648 	case CPU_BLUE:
649 		init_bluelightning();
650 		break;
651 	case CPU_486DLC:
652 		init_486dlc();
653 		break;
654 	case CPU_CY486DX:
655 		init_cy486dx();
656 		break;
657 	case CPU_M1SC:
658 		init_5x86();
659 		break;
660 #ifdef CPU_I486_ON_386
661 	case CPU_486:
662 		init_i486_on_386();
663 		break;
664 #endif
665 	case CPU_M1:
666 		init_6x86();
667 		break;
668 #endif /* I486_CPU */
669 #ifdef I586_CPU
670 	case CPU_586:
671 		switch (cpu_vendor_id) {
672 		case CPU_VENDOR_AMD:
673 #ifdef CPU_WT_ALLOC
674 			if (((cpu_id & 0x0f0) > 0) &&
675 			    ((cpu_id & 0x0f0) < 0x60) &&
676 			    ((cpu_id & 0x00f) > 3))
677 				enable_K5_wt_alloc();
678 			else if (((cpu_id & 0x0f0) > 0x80) ||
679 			    (((cpu_id & 0x0f0) == 0x80) &&
680 				(cpu_id & 0x00f) > 0x07))
681 				enable_K6_2_wt_alloc();
682 			else if ((cpu_id & 0x0f0) > 0x50)
683 				enable_K6_wt_alloc();
684 #endif
685 			if ((cpu_id & 0xf0) == 0xa0)
686 				/*
687 				 * Make sure the TSC runs through
688 				 * suspension, otherwise we can't use
689 				 * it as timecounter
690 				 */
691 				wrmsr(0x1900, rdmsr(0x1900) | 0x20ULL);
692 			break;
693 		case CPU_VENDOR_CENTAUR:
694 			init_winchip();
695 			break;
696 		case CPU_VENDOR_TRANSMETA:
697 			init_transmeta();
698 			break;
699 		case CPU_VENDOR_RISE:
700 			init_rise();
701 			break;
702 		}
703 		break;
704 #endif
705 #ifdef I686_CPU
706 	case CPU_M2:
707 		init_6x86MX();
708 		break;
709 	case CPU_686:
710 		switch (cpu_vendor_id) {
711 		case CPU_VENDOR_INTEL:
712 			switch (cpu_id & 0xff0) {
713 			case 0x610:
714 				init_ppro();
715 				break;
716 			case 0x660:
717 				init_mendocino();
718 				break;
719 			}
720 			break;
721 		case CPU_VENDOR_AMD:
722 #ifdef CPU_ATHLON_SSE_HACK
723 			/*
724 			 * Sometimes the BIOS doesn't enable SSE instructions.
725 			 * According to AMD document 20734, the mobile
726 			 * Duron, the (mobile) Athlon 4 and the Athlon MP
727 			 * support SSE. These correspond to cpu_id 0x66X
728 			 * or 0x67X.
729 			 */
730 			if ((cpu_feature & CPUID_XMM) == 0 &&
731 			    ((cpu_id & ~0xf) == 0x660 ||
732 			     (cpu_id & ~0xf) == 0x670 ||
733 			     (cpu_id & ~0xf) == 0x680)) {
734 				u_int regs[4];
735 				wrmsr(MSR_HWCR, rdmsr(MSR_HWCR) & ~0x08000);
736 				do_cpuid(1, regs);
737 				cpu_feature = regs[3];
738 			}
739 #endif
740 			/*
741 			 * Detect C1E that breaks APIC.  See comment in
742 			 * amd64/initcpu.c.
743 			 */
744 			if ((CPUID_TO_FAMILY(cpu_id) == 0xf ||
745 			    CPUID_TO_FAMILY(cpu_id) == 0x10) &&
746 			    (cpu_feature2 & CPUID2_HV) == 0)
747 				cpu_amdc1e_bug = 1;
748 			break;
749 		case CPU_VENDOR_CENTAUR:
750 			init_via();
751 			break;
752 		case CPU_VENDOR_TRANSMETA:
753 			init_transmeta();
754 			break;
755 		}
756 		break;
757 #endif
758 	default:
759 		break;
760 	}
761 	if ((cpu_feature & CPUID_XMM) && (cpu_feature & CPUID_FXSR)) {
762 		load_cr4(rcr4() | CR4_FXSR | CR4_XMM);
763 		cpu_fxsr = hw_instruction_sse = 1;
764 	}
765 	if (elf32_nxstack) {
766 		msr = rdmsr(MSR_EFER) | EFER_NXE;
767 		wrmsr(MSR_EFER, msr);
768 	}
769 	if ((amd_feature & AMDID_RDTSCP) != 0 ||
770 	    (cpu_stdext_feature2 & CPUID_STDEXT2_RDPID) != 0)
771 		wrmsr(MSR_TSC_AUX, cpu_auxmsr());
772 }
773 
774 void
initializecpucache(void)775 initializecpucache(void)
776 {
777 
778 	/*
779 	 * CPUID with %eax = 1, %ebx returns
780 	 * Bits 15-8: CLFLUSH line size
781 	 * 	(Value * 8 = cache line size in bytes)
782 	 */
783 	if ((cpu_feature & CPUID_CLFSH) != 0)
784 		cpu_clflush_line_size = ((cpu_procinfo >> 8) & 0xff) * 8;
785 	/*
786 	 * XXXKIB: (temporary) hack to work around traps generated
787 	 * when CLFLUSHing APIC register window under virtualization
788 	 * environments.  These environments tend to disable the
789 	 * CPUID_SS feature even though the native CPU supports it.
790 	 */
791 	TUNABLE_INT_FETCH("hw.clflush_disable", &hw_clflush_disable);
792 	if (vm_guest != VM_GUEST_NO && hw_clflush_disable == -1) {
793 		cpu_feature &= ~CPUID_CLFSH;
794 		cpu_stdext_feature &= ~CPUID_STDEXT_CLFLUSHOPT;
795 	}
796 	/*
797 	 * The kernel's use of CLFLUSH{,OPT} can be disabled manually
798 	 * by setting the hw.clflush_disable tunable.
799 	 */
800 	if (hw_clflush_disable == 1) {
801 		cpu_feature &= ~CPUID_CLFSH;
802 		cpu_stdext_feature &= ~CPUID_STDEXT_CLFLUSHOPT;
803 	}
804 }
805 
806 #if defined(I586_CPU) && defined(CPU_WT_ALLOC)
807 /*
808  * Enable write allocate feature of AMD processors.
809  * Following two functions require the Maxmem variable being set.
810  */
811 static void
enable_K5_wt_alloc(void)812 enable_K5_wt_alloc(void)
813 {
814 	u_int64_t	msr;
815 	register_t	saveintr;
816 
817 	/*
818 	 * Write allocate is supported only on models 1, 2, and 3, with
819 	 * a stepping of 4 or greater.
820 	 */
821 	if (((cpu_id & 0xf0) > 0) && ((cpu_id & 0x0f) > 3)) {
822 		saveintr = intr_disable();
823 		msr = rdmsr(0x83);		/* HWCR */
824 		wrmsr(0x83, msr & !(0x10));
825 
826 		/*
827 		 * We have to tell the chip where the top of memory is,
828 		 * since video cards could have frame bufferes there,
829 		 * memory-mapped I/O could be there, etc.
830 		 */
831 		if(Maxmem > 0)
832 		  msr = Maxmem / 16;
833 		else
834 		  msr = 0;
835 		msr |= AMD_WT_ALLOC_TME | AMD_WT_ALLOC_FRE;
836 
837 		/*
838 		 * There is no way to know whether 15-16M hole exists or not.
839 		 * Therefore, we disable write allocate for this range.
840 		 */
841 		wrmsr(0x86, 0x0ff00f0);
842 		msr |= AMD_WT_ALLOC_PRE;
843 		wrmsr(0x85, msr);
844 
845 		msr=rdmsr(0x83);
846 		wrmsr(0x83, msr|0x10); /* enable write allocate */
847 		intr_restore(saveintr);
848 	}
849 }
850 
851 static void
enable_K6_wt_alloc(void)852 enable_K6_wt_alloc(void)
853 {
854 	quad_t	size;
855 	u_int64_t	whcr;
856 	register_t	saveintr;
857 
858 	saveintr = intr_disable();
859 	wbinvd();
860 
861 #ifdef CPU_DISABLE_CACHE
862 	/*
863 	 * Certain K6-2 box becomes unstable when write allocation is
864 	 * enabled.
865 	 */
866 	/*
867 	 * The AMD-K6 processer provides the 64-bit Test Register 12(TR12),
868 	 * but only the Cache Inhibit(CI) (bit 3 of TR12) is supported.
869 	 * All other bits in TR12 have no effect on the processer's operation.
870 	 * The I/O Trap Restart function (bit 9 of TR12) is always enabled
871 	 * on the AMD-K6.
872 	 */
873 	wrmsr(0x0000000e, (u_int64_t)0x0008);
874 #endif
875 	/* Don't assume that memory size is aligned with 4M. */
876 	if (Maxmem > 0)
877 	  size = ((Maxmem >> 8) + 3) >> 2;
878 	else
879 	  size = 0;
880 
881 	/* Limit is 508M bytes. */
882 	if (size > 0x7f)
883 		size = 0x7f;
884 	whcr = (rdmsr(0xc0000082) & ~(0x7fLL << 1)) | (size << 1);
885 
886 #if defined(NO_MEMORY_HOLE)
887 	if (whcr & (0x7fLL << 1))
888 		whcr |=  0x0001LL;
889 #else
890 	/*
891 	 * There is no way to know whether 15-16M hole exists or not.
892 	 * Therefore, we disable write allocate for this range.
893 	 */
894 	whcr &= ~0x0001LL;
895 #endif
896 	wrmsr(0x0c0000082, whcr);
897 
898 	intr_restore(saveintr);
899 }
900 
901 static void
enable_K6_2_wt_alloc(void)902 enable_K6_2_wt_alloc(void)
903 {
904 	quad_t	size;
905 	u_int64_t	whcr;
906 	register_t	saveintr;
907 
908 	saveintr = intr_disable();
909 	wbinvd();
910 
911 #ifdef CPU_DISABLE_CACHE
912 	/*
913 	 * Certain K6-2 box becomes unstable when write allocation is
914 	 * enabled.
915 	 */
916 	/*
917 	 * The AMD-K6 processer provides the 64-bit Test Register 12(TR12),
918 	 * but only the Cache Inhibit(CI) (bit 3 of TR12) is supported.
919 	 * All other bits in TR12 have no effect on the processer's operation.
920 	 * The I/O Trap Restart function (bit 9 of TR12) is always enabled
921 	 * on the AMD-K6.
922 	 */
923 	wrmsr(0x0000000e, (u_int64_t)0x0008);
924 #endif
925 	/* Don't assume that memory size is aligned with 4M. */
926 	if (Maxmem > 0)
927 	  size = ((Maxmem >> 8) + 3) >> 2;
928 	else
929 	  size = 0;
930 
931 	/* Limit is 4092M bytes. */
932 	if (size > 0x3fff)
933 		size = 0x3ff;
934 	whcr = (rdmsr(0xc0000082) & ~(0x3ffLL << 22)) | (size << 22);
935 
936 #if defined(NO_MEMORY_HOLE)
937 	if (whcr & (0x3ffLL << 22))
938 		whcr |=  1LL << 16;
939 #else
940 	/*
941 	 * There is no way to know whether 15-16M hole exists or not.
942 	 * Therefore, we disable write allocate for this range.
943 	 */
944 	whcr &= ~(1LL << 16);
945 #endif
946 	wrmsr(0x0c0000082, whcr);
947 
948 	intr_restore(saveintr);
949 }
950 #endif /* I585_CPU && CPU_WT_ALLOC */
951 
952 #include "opt_ddb.h"
953 #ifdef DDB
954 #include <ddb/ddb.h>
955 
DB_SHOW_COMMAND(cyrixreg,cyrixreg)956 DB_SHOW_COMMAND(cyrixreg, cyrixreg)
957 {
958 	register_t saveintr;
959 	u_int	cr0;
960 	u_char	ccr1, ccr2, ccr3;
961 	u_char	ccr0 = 0, ccr4 = 0, ccr5 = 0, pcr0 = 0;
962 
963 	cr0 = rcr0();
964 	if (cpu_vendor_id == CPU_VENDOR_CYRIX) {
965 		saveintr = intr_disable();
966 
967 		if ((cpu != CPU_M1SC) && (cpu != CPU_CY486DX)) {
968 			ccr0 = read_cyrix_reg(CCR0);
969 		}
970 		ccr1 = read_cyrix_reg(CCR1);
971 		ccr2 = read_cyrix_reg(CCR2);
972 		ccr3 = read_cyrix_reg(CCR3);
973 		if ((cpu == CPU_M1SC) || (cpu == CPU_M1) || (cpu == CPU_M2)) {
974 			write_cyrix_reg(CCR3, CCR3_MAPEN0);
975 			ccr4 = read_cyrix_reg(CCR4);
976 			if ((cpu == CPU_M1) || (cpu == CPU_M2))
977 				ccr5 = read_cyrix_reg(CCR5);
978 			else
979 				pcr0 = read_cyrix_reg(PCR0);
980 			write_cyrix_reg(CCR3, ccr3);		/* Restore CCR3. */
981 		}
982 		intr_restore(saveintr);
983 
984 		if ((cpu != CPU_M1SC) && (cpu != CPU_CY486DX))
985 			printf("CCR0=%x, ", (u_int)ccr0);
986 
987 		printf("CCR1=%x, CCR2=%x, CCR3=%x",
988 			(u_int)ccr1, (u_int)ccr2, (u_int)ccr3);
989 		if ((cpu == CPU_M1SC) || (cpu == CPU_M1) || (cpu == CPU_M2)) {
990 			printf(", CCR4=%x, ", (u_int)ccr4);
991 			if (cpu == CPU_M1SC)
992 				printf("PCR0=%x\n", pcr0);
993 			else
994 				printf("CCR5=%x\n", ccr5);
995 		}
996 	}
997 	printf("CR0=%x\n", cr0);
998 }
999 #endif /* DDB */
1000