xref: /dragonfly/sys/platform/pc64/x86_64/initcpu.c (revision bbb35c81)
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  Unpublished rights reserved under the copyright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/clock.h>
39 #include <machine/cputypes.h>
40 #include <machine/md_var.h>
41 #include <machine/specialreg.h>
42 #include <machine/smp.h>
43 
44 #include <vm/vm.h>
45 #include <vm/pmap.h>
46 
47 static int tsc_ignore_cpuid = 0;
48 TUNABLE_INT("hw.tsc_ignore_cpuid", &tsc_ignore_cpuid);
49 
50 static int	hw_instruction_sse;
51 SYSCTL_INT(_hw, OID_AUTO, instruction_sse, CTLFLAG_RD,
52     &hw_instruction_sse, 0, "SIMD/MMX2 instructions available in CPU");
53 
54 int	cpu_type;		/* XXX CPU_CLAWHAMMER */
55 u_int	cpu_feature;		/* Feature flags */
56 u_int	cpu_feature2;		/* Feature flags */
57 u_int	amd_feature;		/* AMD feature flags */
58 u_int	amd_feature2;		/* AMD feature flags */
59 u_int	via_feature_rng;	/* VIA RNG features */
60 u_int	via_feature_xcrypt;	/* VIA ACE features */
61 u_int	cpu_high;		/* Highest arg to CPUID */
62 u_int	cpu_exthigh;		/* Highest arg to extended CPUID */
63 u_int	cpu_id;			/* Stepping ID */
64 u_int	cpu_procinfo;		/* HyperThreading Info / Brand Index / CLFUSH */
65 u_int	cpu_procinfo2;		/* Multicore info */
66 char	cpu_vendor[20];		/* CPU Origin code */
67 u_int	cpu_vendor_id;		/* CPU vendor ID */
68 u_int	cpu_fxsr;		/* SSE enabled */
69 u_int	cpu_xsave;		/* Using XSAVE */
70 u_int	cpu_clflush_line_size = 32;	/* Default CLFLUSH line size */
71 u_int	cpu_stdext_feature;
72 u_int	cpu_stdext_feature2;
73 u_int	cpu_stdext_feature3;
74 u_long	cpu_ia32_arch_caps;
75 u_int	cpu_thermal_feature;
76 u_int	cpu_mwait_feature;
77 u_int	cpu_mwait_extemu;
78 
79 /*
80  * -1: automatic (enable on h/w, disable on VMs)
81  * 0: disable
82  * 1: enable (where available)
83  */
84 static int hw_clflush_enable = -1;
85 
86 SYSCTL_INT(_hw, OID_AUTO, clflush_enable, CTLFLAG_RD, &hw_clflush_enable, 0,
87 	   "");
88 
89 SYSCTL_UINT(_hw, OID_AUTO, via_feature_rng, CTLFLAG_RD,
90 	&via_feature_rng, 0, "VIA C3/C7 RNG feature available in CPU");
91 SYSCTL_UINT(_hw, OID_AUTO, via_feature_xcrypt, CTLFLAG_RD,
92 	&via_feature_xcrypt, 0, "VIA C3/C7 xcrypt feature available in CPU");
93 
94 /*
95  * Initialize special VIA C3/C7 features
96  */
97 static void
98 init_via(void)
99 {
100 	u_int regs[4], val;
101 	u_int64_t msreg;
102 
103 	do_cpuid(0xc0000000, regs);
104 	val = regs[0];
105 	if (val >= 0xc0000001) {
106 		do_cpuid(0xc0000001, regs);
107 		val = regs[3];
108 	} else
109 		val = 0;
110 
111 	/* Enable RNG if present and disabled */
112 	if (val & VIA_CPUID_HAS_RNG) {
113 		if (!(val & VIA_CPUID_DO_RNG)) {
114 			msreg = rdmsr(0x110B);
115 			msreg |= 0x40;
116 			wrmsr(0x110B, msreg);
117 		}
118 		via_feature_rng = VIA_HAS_RNG;
119 	}
120 	/* Enable AES engine if present and disabled */
121 	if (val & VIA_CPUID_HAS_ACE) {
122 		if (!(val & VIA_CPUID_DO_ACE)) {
123 			msreg = rdmsr(0x1107);
124 			msreg |= (0x01 << 28);
125 			wrmsr(0x1107, msreg);
126 		}
127 		via_feature_xcrypt |= VIA_HAS_AES;
128 	}
129 	/* Enable ACE2 engine if present and disabled */
130 	if (val & VIA_CPUID_HAS_ACE2) {
131 		if (!(val & VIA_CPUID_DO_ACE2)) {
132 			msreg = rdmsr(0x1107);
133 			msreg |= (0x01 << 28);
134 			wrmsr(0x1107, msreg);
135 		}
136 		via_feature_xcrypt |= VIA_HAS_AESCTR;
137 	}
138 	/* Enable SHA engine if present and disabled */
139 	if (val & VIA_CPUID_HAS_PHE) {
140 		if (!(val & VIA_CPUID_DO_PHE)) {
141 			msreg = rdmsr(0x1107);
142 			msreg |= (0x01 << 28/**/);
143 			wrmsr(0x1107, msreg);
144 		}
145 		via_feature_xcrypt |= VIA_HAS_SHA;
146 	}
147 	/* Enable MM engine if present and disabled */
148 	if (val & VIA_CPUID_HAS_PMM) {
149 		if (!(val & VIA_CPUID_DO_PMM)) {
150 			msreg = rdmsr(0x1107);
151 			msreg |= (0x01 << 28/**/);
152 			wrmsr(0x1107, msreg);
153 		}
154 		via_feature_xcrypt |= VIA_HAS_MM;
155 	}
156 }
157 
158 static enum vmm_guest_type
159 detect_vmm(void)
160 {
161 	enum vmm_guest_type guest;
162 	char vendor[16];
163 
164 	/*
165 	 * [RFC] CPUID usage for interaction between Hypervisors and Linux.
166 	 * http://lkml.org/lkml/2008/10/1/246
167 	 *
168 	 * KB1009458: Mechanisms to determine if software is running in
169 	 * a VMware virtual machine
170 	 * http://kb.vmware.com/kb/1009458
171 	 */
172 	if (cpu_feature2 & CPUID2_VMM) {
173 		u_int regs[4];
174 
175 		do_cpuid(0x40000000, regs);
176 		((u_int *)&vendor)[0] = regs[1];
177 		((u_int *)&vendor)[1] = regs[2];
178 		((u_int *)&vendor)[2] = regs[3];
179 		vendor[12] = '\0';
180 		if (regs[0] >= 0x40000000) {
181 			memcpy(vmm_vendor, vendor, 13);
182 			if (strcmp(vmm_vendor, "VMwareVMware") == 0)
183 				return VMM_GUEST_VMWARE;
184 			else if (strcmp(vmm_vendor, "Microsoft Hv") == 0)
185 				return VMM_GUEST_HYPERV;
186 			else if (strcmp(vmm_vendor, "KVMKVMKVM") == 0)
187 				return VMM_GUEST_KVM;
188 		} else if (regs[0] == 0) {
189 			/* Also detect old KVM versions with regs[0] == 0 */
190 			if (strcmp(vendor, "KVMKVMKVM") == 0) {
191 				memcpy(vmm_vendor, vendor, 13);
192 				return VMM_GUEST_KVM;
193 			}
194 		}
195 	}
196 
197 	guest = detect_virtual();
198 	if (guest == VMM_GUEST_NONE && (cpu_feature2 & CPUID2_VMM))
199 		guest = VMM_GUEST_UNKNOWN;
200 	return guest;
201 }
202 
203 /*
204  * Initialize CPU control registers
205  */
206 void
207 initializecpu(int cpu)
208 {
209 	uint64_t msr;
210 
211 	/*
212 	 * Check for FXSR and SSE support and enable if available
213 	 */
214 	if ((cpu_feature & CPUID_XMM) && (cpu_feature & CPUID_FXSR)) {
215 		load_cr4(rcr4() | CR4_FXSR | CR4_XMM);
216 		cpu_fxsr = hw_instruction_sse = 1;
217 	}
218 
219 	if (cpu == 0) {
220 		/* Check if we are running in a hypervisor. */
221 		vmm_guest = detect_vmm();
222 	}
223 
224 #if !defined(CPU_DISABLE_AVX)
225 	/* Use XSAVE if supported */
226 	if (cpu_feature2 & CPUID2_XSAVE) {
227 		load_cr4(rcr4() | CR4_XSAVE);
228 
229 		/* Adjust size of savefpu in npx.h before adding to mask.*/
230 		npx_xcr0_mask = CPU_XFEATURE_X87 | CPU_XFEATURE_SSE;
231 		if (cpu_feature2 & CPUID2_AVX)
232 			npx_xcr0_mask |= CPU_XFEATURE_YMM;
233 
234 		xsetbv(0, npx_xcr0_mask);
235 		cpu_xsave = 1;
236 	}
237 #endif
238 
239 	if (cpu_vendor_id == CPU_VENDOR_AMD) {
240 		switch((cpu_id & 0xFF0000)) {
241 		case 0x100000:
242 		case 0x120000:
243 			/*
244 			 * Errata 721 is the cpu bug found by your's truly
245 			 * (Matthew Dillon).  It is a bug where a sequence
246 			 * of 5 or more popq's + a retq, under involved
247 			 * deep recursion circumstances, can cause the %rsp
248 			 * to not be properly updated, almost always
249 			 * resulting in a seg-fault soon after.
250 			 *
251 			 * Do not install the workaround when we are running
252 			 * in a virtual machine.
253 			 */
254 			if (vmm_guest)
255 				break;
256 
257 			msr = rdmsr(MSR_AMD_DE_CFG);
258 			if ((msr & 1) == 0) {
259 				if (cpu == 0)
260 					kprintf("Errata 721 workaround "
261 						"installed\n");
262 				msr |= 1;
263 				wrmsr(MSR_AMD_DE_CFG, msr);
264 			}
265 			break;
266 		}
267 
268 		/*
269 		 * BIOS may fail to set InitApicIdCpuIdLo to 1 as it should
270 		 * per BKDG.  So, do it here or otherwise some tools could
271 		 * be confused by Initial Local APIC ID reported with
272 		 * CPUID Function 1 in EBX.
273 		 */
274 		if (CPUID_TO_FAMILY(cpu_id) == 0x10) {
275 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
276 				msr = rdmsr(0xc001001f);
277 				msr |= (uint64_t)1 << 54;
278 				wrmsr(0xc001001f, msr);
279 			}
280 		}
281 
282 		/*
283 		 * BIOS may configure Family 10h processors to convert
284 		 * WC+ cache type to CD.  That can hurt performance of
285 		 * guest VMs using nested paging.
286 		 *
287 		 * The relevant MSR bit is not documented in the BKDG,
288 		 * the fix is borrowed from Linux.
289 		 */
290 		if (CPUID_TO_FAMILY(cpu_id) == 0x10) {
291 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
292 				msr = rdmsr(0xc001102a);
293 				msr &= ~((uint64_t)1 << 24);
294 				wrmsr(0xc001102a, msr);
295 			}
296 		}
297 
298 		/*
299 		 * Work around Erratum 793: Specific Combination of Writes
300 		 * to Write Combined Memory Types and Locked Instructions
301 		 * May Cause Core Hang.  See Revision Guide for AMD Family
302 		 * 16h Models 00h-0Fh Processors, revision 3.04 or later,
303 		 * publication 51810.
304 		 */
305 		if (CPUID_TO_FAMILY(cpu_id) == 0x16 &&
306 		    CPUID_TO_MODEL(cpu_id) <= 0xf) {
307 			if ((cpu_feature2 & CPUID2_VMM) == 0) {
308 				msr = rdmsr(0xc0011020);
309 				msr |= (uint64_t)1 << 15;
310 				wrmsr(0xc0011020, msr);
311 			}
312 		}
313 	}
314 
315 	if ((amd_feature & AMDID_NX) != 0) {
316 		msr = rdmsr(MSR_EFER) | EFER_NXE;
317 		wrmsr(MSR_EFER, msr);
318 #if 0 /* JG */
319 		pg_nx = PG_NX;
320 #endif
321 	}
322 	if (cpu_vendor_id == CPU_VENDOR_CENTAUR &&
323 	    CPUID_TO_FAMILY(cpu_id) == 0x6 &&
324 	    CPUID_TO_MODEL(cpu_id) >= 0xf)
325 		init_via();
326 
327 	TUNABLE_INT_FETCH("hw.clflush_enable", &hw_clflush_enable);
328 	if (cpu_feature & CPUID_CLFSH) {
329 		cpu_clflush_line_size = ((cpu_procinfo >> 8) & 0xff) * 8;
330 
331 		if (hw_clflush_enable == 0 ||
332 		    ((hw_clflush_enable == -1) && vmm_guest))
333 			cpu_feature &= ~CPUID_CLFSH;
334 	}
335 
336 	/* Set TSC_AUX register to the cpuid, for using rdtscp in userland. */
337 	if ((amd_feature & AMDID_RDTSCP) != 0)
338 		wrmsr(MSR_TSCAUX, cpu);
339 }
340 
341 /*
342  * This method should be at least as good as calibrating the TSC based on the
343  * HPET timer, since the HPET runs with the core crystal clock apparently.
344  */
345 static void
346 detect_tsc_frequency(void)
347 {
348 	int cpu_family, cpu_model;
349 	u_int regs[4];
350 	uint64_t crystal = 0;
351 
352 	cpu_model = CPUID_TO_MODEL(cpu_id);
353 	cpu_family = CPUID_TO_FAMILY(cpu_id);
354 
355 	if (cpu_vendor_id != CPU_VENDOR_INTEL)
356 		return;
357 
358 	if (cpu_high < 0x15)
359 		return;
360 
361 	do_cpuid(0x15, regs);
362 	if (regs[0] == 0 || regs[1] == 0)
363 		return;
364 
365 	if (regs[2] == 0) {
366 		/* For some families the SDM contains the core crystal clock. */
367 		if (cpu_family == 0x6) {
368 			switch (cpu_model) {
369 			case 0x55:	/* Xeon Scalable */
370 				crystal = 25000000;	/* 25 MHz */
371 				break;
372 			/* Skylake */
373 			case 0x4e:
374 			case 0x5e:
375 			/* Kabylake/Coffeelake */
376 			case 0x8e:
377 			case 0x9e:
378 				crystal = 24000000;	/* 24 MHz */
379 				break;
380 			case 0x5c:	/* Goldmont Atom */
381 				crystal = 19200000;	/* 19.2 MHz */
382 				break;
383 			default:
384 				break;
385 			}
386 		}
387 	} else {
388 		crystal = regs[2];
389 	}
390 
391 	if (crystal == 0)
392 		return;
393 
394 	kprintf("TSC crystal clock: %ju Hz, TSC/crystal ratio: %u/%u\n",
395 	    crystal, regs[1], regs[0]);
396 
397 	if (tsc_ignore_cpuid == 0) {
398 		tsc_frequency = (crystal * regs[1]) / regs[0];
399 		i8254_cputimer_disable = 1;
400 	}
401 }
402 
403 TIMECOUNTER_INIT(cpuid_tsc_frequency, detect_tsc_frequency);
404