xref: /dragonfly/sys/platform/pc64/x86_64/initcpu.c (revision 6a3cbbc2)
1 /*-
2  * Copyright (c) KATO Takenori, 1997, 1998.
3  * Copyright (c) 2008 The DragonFly Project.
4  *
5  * All rights reserved.  Unpublished rights reserved under the copyright
6  * laws of Japan.
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  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer as
14  *    the first lines of this file unmodified.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include "opt_cpu.h"
32 
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/systm.h>
36 #include <sys/sysctl.h>
37 
38 #include <machine/cputypes.h>
39 #include <machine/md_var.h>
40 #include <machine/specialreg.h>
41 #include <machine/smp.h>
42 
43 #include <vm/vm.h>
44 #include <vm/pmap.h>
45 
46 extern int i8254_cputimer_disable;
47 
48 static int tsc_ignore_cpuid = 0;
49 TUNABLE_INT("hw.tsc_ignore_cpuid", &tsc_ignore_cpuid);
50 
51 static int	hw_instruction_sse;
52 SYSCTL_INT(_hw, OID_AUTO, instruction_sse, CTLFLAG_RD,
53     &hw_instruction_sse, 0, "SIMD/MMX2 instructions available in CPU");
54 
55 int	cpu_type;		/* XXX CPU_CLAWHAMMER */
56 u_int	cpu_feature;		/* Feature flags */
57 u_int	cpu_feature2;		/* Feature flags */
58 u_int	amd_feature;		/* AMD feature flags */
59 u_int	amd_feature2;		/* AMD feature flags */
60 u_int	via_feature_rng;	/* VIA RNG features */
61 u_int	via_feature_xcrypt;	/* VIA ACE features */
62 u_int	cpu_high;		/* Highest arg to CPUID */
63 u_int	cpu_exthigh;		/* Highest arg to extended CPUID */
64 u_int	cpu_id;			/* Stepping ID */
65 u_int	cpu_procinfo;		/* HyperThreading Info / Brand Index / CLFUSH */
66 u_int	cpu_procinfo2;		/* Multicore info */
67 char	cpu_vendor[20];		/* CPU Origin code */
68 u_int	cpu_vendor_id;		/* CPU vendor ID */
69 u_int	cpu_fxsr;		/* SSE enabled */
70 u_int	cpu_xsave;		/* AVX enabled by OS*/
71 u_int	cpu_mxcsr_mask;		/* Valid bits in mxcsr */
72 u_int	cpu_clflush_line_size = 32;	/* Default CLFLUSH line size */
73 u_int	cpu_stdext_feature;
74 u_int	cpu_thermal_feature;
75 u_int	cpu_mwait_feature;
76 u_int	cpu_mwait_extemu;
77 
78 /*
79  * -1: automatic (enable on h/w, disable on VMs)
80  * 0: disable
81  * 1: enable (where available)
82  */
83 static int hw_clflush_enable = -1;
84 
85 SYSCTL_INT(_hw, OID_AUTO, clflush_enable, CTLFLAG_RD, &hw_clflush_enable, 0,
86 	   "");
87 
88 SYSCTL_UINT(_hw, OID_AUTO, via_feature_rng, CTLFLAG_RD,
89 	&via_feature_rng, 0, "VIA C3/C7 RNG feature available in CPU");
90 SYSCTL_UINT(_hw, OID_AUTO, via_feature_xcrypt, CTLFLAG_RD,
91 	&via_feature_xcrypt, 0, "VIA C3/C7 xcrypt feature available in CPU");
92 
93 /*
94  * Initialize special VIA C3/C7 features
95  */
96 static void
97 init_via(void)
98 {
99 	u_int regs[4], val;
100 	u_int64_t msreg;
101 
102 	do_cpuid(0xc0000000, regs);
103 	val = regs[0];
104 	if (val >= 0xc0000001) {
105 		do_cpuid(0xc0000001, regs);
106 		val = regs[3];
107 	} else
108 		val = 0;
109 
110 	/* Enable RNG if present and disabled */
111 	if (val & VIA_CPUID_HAS_RNG) {
112 		if (!(val & VIA_CPUID_DO_RNG)) {
113 			msreg = rdmsr(0x110B);
114 			msreg |= 0x40;
115 			wrmsr(0x110B, msreg);
116 		}
117 		via_feature_rng = VIA_HAS_RNG;
118 	}
119 	/* Enable AES engine if present and disabled */
120 	if (val & VIA_CPUID_HAS_ACE) {
121 		if (!(val & VIA_CPUID_DO_ACE)) {
122 			msreg = rdmsr(0x1107);
123 			msreg |= (0x01 << 28);
124 			wrmsr(0x1107, msreg);
125 		}
126 		via_feature_xcrypt |= VIA_HAS_AES;
127 	}
128 	/* Enable ACE2 engine if present and disabled */
129 	if (val & VIA_CPUID_HAS_ACE2) {
130 		if (!(val & VIA_CPUID_DO_ACE2)) {
131 			msreg = rdmsr(0x1107);
132 			msreg |= (0x01 << 28);
133 			wrmsr(0x1107, msreg);
134 		}
135 		via_feature_xcrypt |= VIA_HAS_AESCTR;
136 	}
137 	/* Enable SHA engine if present and disabled */
138 	if (val & VIA_CPUID_HAS_PHE) {
139 		if (!(val & VIA_CPUID_DO_PHE)) {
140 			msreg = rdmsr(0x1107);
141 			msreg |= (0x01 << 28/**/);
142 			wrmsr(0x1107, msreg);
143 		}
144 		via_feature_xcrypt |= VIA_HAS_SHA;
145 	}
146 	/* Enable MM engine if present and disabled */
147 	if (val & VIA_CPUID_HAS_PMM) {
148 		if (!(val & VIA_CPUID_DO_PMM)) {
149 			msreg = rdmsr(0x1107);
150 			msreg |= (0x01 << 28/**/);
151 			wrmsr(0x1107, msreg);
152 		}
153 		via_feature_xcrypt |= VIA_HAS_MM;
154 	}
155 }
156 
157 static enum vmm_guest_type
158 detect_vmm(void)
159 {
160 	enum vmm_guest_type guest;
161 	char vendor[16];
162 
163 	/*
164 	 * [RFC] CPUID usage for interaction between Hypervisors and Linux.
165 	 * http://lkml.org/lkml/2008/10/1/246
166 	 *
167 	 * KB1009458: Mechanisms to determine if software is running in
168 	 * a VMware virtual machine
169 	 * http://kb.vmware.com/kb/1009458
170 	 */
171 	if (cpu_feature2 & CPUID2_VMM) {
172 		u_int regs[4];
173 
174 		do_cpuid(0x40000000, regs);
175 		((u_int *)&vendor)[0] = regs[1];
176 		((u_int *)&vendor)[1] = regs[2];
177 		((u_int *)&vendor)[2] = regs[3];
178 		vendor[12] = '\0';
179 		if (regs[0] >= 0x40000000) {
180 			memcpy(vmm_vendor, vendor, 13);
181 			if (strcmp(vmm_vendor, "VMwareVMware") == 0)
182 				return VMM_GUEST_VMWARE;
183 			else if (strcmp(vmm_vendor, "Microsoft Hv") == 0)
184 				return VMM_GUEST_HYPERV;
185 			else if (strcmp(vmm_vendor, "KVMKVMKVM") == 0)
186 				return VMM_GUEST_KVM;
187 		} else if (regs[0] == 0) {
188 			/* Also detect old KVM versions with regs[0] == 0 */
189 			if (strcmp(vendor, "KVMKVMKVM") == 0) {
190 				memcpy(vmm_vendor, vendor, 13);
191 				return VMM_GUEST_KVM;
192 			}
193 		}
194 	}
195 
196 	guest = detect_virtual();
197 	if (guest == VMM_GUEST_NONE && (cpu_feature2 & CPUID2_VMM))
198 		guest = VMM_GUEST_UNKNOWN;
199 	return guest;
200 }
201 
202 /*
203  * Initialize CPU control registers
204  */
205 void
206 initializecpu(int cpu)
207 {
208 	uint64_t msr;
209 
210 	/*
211 	 * Check for FXSR and SSE support and enable if available
212 	 */
213 	if ((cpu_feature & CPUID_XMM) && (cpu_feature & CPUID_FXSR)) {
214 		load_cr4(rcr4() | CR4_FXSR | CR4_XMM);
215 		cpu_fxsr = hw_instruction_sse = 1;
216 	}
217 
218 	if (cpu == 0) {
219 		/* Check if we are running in a hypervisor. */
220 		vmm_guest = detect_vmm();
221 	}
222 
223 #if !defined(CPU_DISABLE_AVX)
224 	/*Check for XSAVE and AVX support and enable if available.*/
225 	if ((cpu_feature2 & CPUID2_AVX) && (cpu_feature2 & CPUID2_XSAVE)
226 	     && (cpu_feature & CPUID_SSE)) {
227 		load_cr4(rcr4() | CR4_XSAVE);
228 
229 		/* Adjust size of savefpu in npx.h before adding to mask.*/
230 		xsetbv(0, CPU_XFEATURE_X87 | CPU_XFEATURE_SSE | CPU_XFEATURE_YMM, 0);
231 		cpu_xsave = 1;
232 	}
233 #endif
234 
235 	if (cpu_vendor_id == CPU_VENDOR_AMD) {
236 		switch((cpu_id & 0xFF0000)) {
237 		case 0x100000:
238 		case 0x120000:
239 			/*
240 			 * Errata 721 is the cpu bug found by your's truly
241 			 * (Matthew Dillon).  It is a bug where a sequence
242 			 * of 5 or more popq's + a retq, under involved
243 			 * deep recursion circumstances, can cause the %rsp
244 			 * to not be properly updated, almost always
245 			 * resulting in a seg-fault soon after.
246 			 *
247 			 * Do not install the workaround when we are running
248 			 * in a virtual machine.
249 			 */
250 			if (vmm_guest)
251 				break;
252 
253 			msr = rdmsr(MSR_AMD_DE_CFG);
254 			if ((msr & 1) == 0) {
255 				if (cpu == 0)
256 					kprintf("Errata 721 workaround "
257 						"installed\n");
258 				msr |= 1;
259 				wrmsr(MSR_AMD_DE_CFG, msr);
260 			}
261 			break;
262 		}
263 
264 		/*
265 		 * BIOS may fail to set InitApicIdCpuIdLo to 1 as it should
266 		 * per BKDG.  So, do it here or otherwise some tools could
267 		 * be confused by Initial Local APIC ID reported with
268 		 * CPUID Function 1 in EBX.
269 		 */
270 		if (CPUID_TO_FAMILY(cpu_id) == 0x10) {
271 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
272 				msr = rdmsr(0xc001001f);
273 				msr |= (uint64_t)1 << 54;
274 				wrmsr(0xc001001f, msr);
275 			}
276 		}
277 
278 		/*
279 		 * BIOS may configure Family 10h processors to convert
280 		 * WC+ cache type to CD.  That can hurt performance of
281 		 * guest VMs using nested paging.
282 		 *
283 		 * The relevant MSR bit is not documented in the BKDG,
284 		 * the fix is borrowed from Linux.
285 		 */
286 		if (CPUID_TO_FAMILY(cpu_id) == 0x10) {
287 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
288 				msr = rdmsr(0xc001102a);
289 				msr &= ~((uint64_t)1 << 24);
290 				wrmsr(0xc001102a, msr);
291 			}
292 		}
293 
294 		/*
295 		 * Work around Erratum 793: Specific Combination of Writes
296 		 * to Write Combined Memory Types and Locked Instructions
297 		 * May Cause Core Hang.  See Revision Guide for AMD Family
298 		 * 16h Models 00h-0Fh Processors, revision 3.04 or later,
299 		 * publication 51810.
300 		 */
301 		if (CPUID_TO_FAMILY(cpu_id) == 0x16 &&
302 		    CPUID_TO_MODEL(cpu_id) <= 0xf) {
303 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
304 				msr = rdmsr(0xc0011020);
305 				msr |= (uint64_t)1 << 15;
306 				wrmsr(0xc0011020, msr);
307 			}
308 		}
309 	}
310 
311 	if ((amd_feature & AMDID_NX) != 0) {
312 		msr = rdmsr(MSR_EFER) | EFER_NXE;
313 		wrmsr(MSR_EFER, msr);
314 #if 0 /* JG */
315 		pg_nx = PG_NX;
316 #endif
317 	}
318 	if (cpu_vendor_id == CPU_VENDOR_CENTAUR &&
319 	    CPUID_TO_FAMILY(cpu_id) == 0x6 &&
320 	    CPUID_TO_MODEL(cpu_id) >= 0xf)
321 		init_via();
322 
323 	TUNABLE_INT_FETCH("hw.clflush_enable", &hw_clflush_enable);
324 	if (cpu_feature & CPUID_CLFSH) {
325 		cpu_clflush_line_size = ((cpu_procinfo >> 8) & 0xff) * 8;
326 
327 		if (hw_clflush_enable == 0 ||
328 		    ((hw_clflush_enable == -1) && vmm_guest))
329 			cpu_feature &= ~CPUID_CLFSH;
330 	}
331 
332 	/* Set TSC_AUX register to the cpuid, for using rdtscp in userland. */
333 	if ((amd_feature & AMDID_RDTSCP) != 0)
334 		wrmsr(MSR_TSCAUX, cpu);
335 }
336 
337 /*
338  * This method should be at least as good as calibrating the TSC based on the
339  * HPET timer, since the HPET runs with the core crystal clock apparently.
340  */
341 static void
342 detect_tsc_frequency(void)
343 {
344 	int cpu_family, cpu_model;
345 	u_int regs[4];
346 	uint64_t crystal = 0;
347 
348 	cpu_model = CPUID_TO_MODEL(cpu_id);
349 	cpu_family = CPUID_TO_FAMILY(cpu_id);
350 
351 	if (cpu_vendor_id != CPU_VENDOR_INTEL)
352 		return;
353 
354 	if (cpu_high < 0x15)
355 		return;
356 
357 	do_cpuid(0x15, regs);
358 	if (regs[0] == 0 || regs[1] == 0)
359 		return;
360 
361 	if (regs[2] == 0) {
362 		/* For some families the SDM contains the core crystal clock. */
363 		if (cpu_family == 0x6) {
364 			switch (cpu_model) {
365 			case 0x55:	/* Xeon Scalable */
366 				crystal = 25000000;	/* 25 MHz */
367 				break;
368 			/* Skylake */
369 			case 0x4e:
370 			case 0x5e:
371 			/* Kabylake/Coffeelake */
372 			case 0x8e:
373 			case 0x9e:
374 				crystal = 24000000;	/* 24 MHz */
375 				break;
376 			case 0x5c:	/* Goldmont Atom */
377 				crystal = 19200000;	/* 19.2 MHz */
378 				break;
379 			default:
380 				break;
381 			}
382 		}
383 	} else {
384 		crystal = regs[2];
385 	}
386 
387 	if (crystal == 0)
388 		return;
389 
390 	kprintf("TSC crystal clock: %ju Hz, TSC/crystal ratio: %u/%u\n",
391 	    crystal, regs[1], regs[0]);
392 
393 	if (tsc_ignore_cpuid == 0) {
394 		tsc_frequency = (crystal * regs[1]) / regs[0];
395 		i8254_cputimer_disable = 1;
396 	}
397 }
398 
399 TIMECOUNTER_INIT(cpuid_tsc_frequency, detect_tsc_frequency);
400