xref: /openbmc/u-boot/arch/x86/cpu/cpu.c (revision 11ac2363)
1 /*
2  * (C) Copyright 2008-2011
3  * Graeme Russ, <graeme.russ@gmail.com>
4  *
5  * (C) Copyright 2002
6  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
7  *
8  * (C) Copyright 2002
9  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
10  * Marius Groeger <mgroeger@sysgo.de>
11  *
12  * (C) Copyright 2002
13  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
14  * Alex Zuepke <azu@sysgo.de>
15  *
16  * Part of this file is adapted from coreboot
17  * src/arch/x86/lib/cpu.c
18  *
19  * SPDX-License-Identifier:	GPL-2.0+
20  */
21 
22 #include <common.h>
23 #include <command.h>
24 #include <dm.h>
25 #include <errno.h>
26 #include <malloc.h>
27 #include <asm/control_regs.h>
28 #include <asm/cpu.h>
29 #include <asm/lapic.h>
30 #include <asm/mp.h>
31 #include <asm/msr.h>
32 #include <asm/mtrr.h>
33 #include <asm/post.h>
34 #include <asm/processor.h>
35 #include <asm/processor-flags.h>
36 #include <asm/interrupt.h>
37 #include <asm/tables.h>
38 #include <linux/compiler.h>
39 
40 DECLARE_GLOBAL_DATA_PTR;
41 
42 /*
43  * Constructor for a conventional segment GDT (or LDT) entry
44  * This is a macro so it can be used in initialisers
45  */
46 #define GDT_ENTRY(flags, base, limit)			\
47 	((((base)  & 0xff000000ULL) << (56-24)) |	\
48 	 (((flags) & 0x0000f0ffULL) << 40) |		\
49 	 (((limit) & 0x000f0000ULL) << (48-16)) |	\
50 	 (((base)  & 0x00ffffffULL) << 16) |		\
51 	 (((limit) & 0x0000ffffULL)))
52 
53 struct gdt_ptr {
54 	u16 len;
55 	u32 ptr;
56 } __packed;
57 
58 struct cpu_device_id {
59 	unsigned vendor;
60 	unsigned device;
61 };
62 
63 struct cpuinfo_x86 {
64 	uint8_t x86;            /* CPU family */
65 	uint8_t x86_vendor;     /* CPU vendor */
66 	uint8_t x86_model;
67 	uint8_t x86_mask;
68 };
69 
70 /*
71  * List of cpu vendor strings along with their normalized
72  * id values.
73  */
74 static struct {
75 	int vendor;
76 	const char *name;
77 } x86_vendors[] = {
78 	{ X86_VENDOR_INTEL,     "GenuineIntel", },
79 	{ X86_VENDOR_CYRIX,     "CyrixInstead", },
80 	{ X86_VENDOR_AMD,       "AuthenticAMD", },
81 	{ X86_VENDOR_UMC,       "UMC UMC UMC ", },
82 	{ X86_VENDOR_NEXGEN,    "NexGenDriven", },
83 	{ X86_VENDOR_CENTAUR,   "CentaurHauls", },
84 	{ X86_VENDOR_RISE,      "RiseRiseRise", },
85 	{ X86_VENDOR_TRANSMETA, "GenuineTMx86", },
86 	{ X86_VENDOR_TRANSMETA, "TransmetaCPU", },
87 	{ X86_VENDOR_NSC,       "Geode by NSC", },
88 	{ X86_VENDOR_SIS,       "SiS SiS SiS ", },
89 };
90 
91 static const char *const x86_vendor_name[] = {
92 	[X86_VENDOR_INTEL]     = "Intel",
93 	[X86_VENDOR_CYRIX]     = "Cyrix",
94 	[X86_VENDOR_AMD]       = "AMD",
95 	[X86_VENDOR_UMC]       = "UMC",
96 	[X86_VENDOR_NEXGEN]    = "NexGen",
97 	[X86_VENDOR_CENTAUR]   = "Centaur",
98 	[X86_VENDOR_RISE]      = "Rise",
99 	[X86_VENDOR_TRANSMETA] = "Transmeta",
100 	[X86_VENDOR_NSC]       = "NSC",
101 	[X86_VENDOR_SIS]       = "SiS",
102 };
103 
104 static void load_ds(u32 segment)
105 {
106 	asm volatile("movl %0, %%ds" : : "r" (segment * X86_GDT_ENTRY_SIZE));
107 }
108 
109 static void load_es(u32 segment)
110 {
111 	asm volatile("movl %0, %%es" : : "r" (segment * X86_GDT_ENTRY_SIZE));
112 }
113 
114 static void load_fs(u32 segment)
115 {
116 	asm volatile("movl %0, %%fs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
117 }
118 
119 static void load_gs(u32 segment)
120 {
121 	asm volatile("movl %0, %%gs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
122 }
123 
124 static void load_ss(u32 segment)
125 {
126 	asm volatile("movl %0, %%ss" : : "r" (segment * X86_GDT_ENTRY_SIZE));
127 }
128 
129 static void load_gdt(const u64 *boot_gdt, u16 num_entries)
130 {
131 	struct gdt_ptr gdt;
132 
133 	gdt.len = (num_entries * X86_GDT_ENTRY_SIZE) - 1;
134 	gdt.ptr = (u32)boot_gdt;
135 
136 	asm volatile("lgdtl %0\n" : : "m" (gdt));
137 }
138 
139 void setup_gdt(gd_t *id, u64 *gdt_addr)
140 {
141 	id->arch.gdt = gdt_addr;
142 	/* CS: code, read/execute, 4 GB, base 0 */
143 	gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
144 
145 	/* DS: data, read/write, 4 GB, base 0 */
146 	gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
147 
148 	/* FS: data, read/write, 4 GB, base (Global Data Pointer) */
149 	id->arch.gd_addr = id;
150 	gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093,
151 		     (ulong)&id->arch.gd_addr, 0xfffff);
152 
153 	/* 16-bit CS: code, read/execute, 64 kB, base 0 */
154 	gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x009b, 0, 0x0ffff);
155 
156 	/* 16-bit DS: data, read/write, 64 kB, base 0 */
157 	gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x0093, 0, 0x0ffff);
158 
159 	gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_CS] = GDT_ENTRY(0x809b, 0, 0xfffff);
160 	gdt_addr[X86_GDT_ENTRY_16BIT_FLAT_DS] = GDT_ENTRY(0x8093, 0, 0xfffff);
161 
162 	load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
163 	load_ds(X86_GDT_ENTRY_32BIT_DS);
164 	load_es(X86_GDT_ENTRY_32BIT_DS);
165 	load_gs(X86_GDT_ENTRY_32BIT_DS);
166 	load_ss(X86_GDT_ENTRY_32BIT_DS);
167 	load_fs(X86_GDT_ENTRY_32BIT_FS);
168 }
169 
170 #ifdef CONFIG_HAVE_FSP
171 /*
172  * Setup FSP execution environment GDT
173  *
174  * Per Intel FSP external architecture specification, before calling any FSP
175  * APIs, we need make sure the system is in flat 32-bit mode and both the code
176  * and data selectors should have full 4GB access range. Here we reuse the one
177  * we used in arch/x86/cpu/start16.S, and reload the segement registers.
178  */
179 void setup_fsp_gdt(void)
180 {
181 	load_gdt((const u64 *)(gdt_rom + CONFIG_RESET_SEG_START), 4);
182 	load_ds(X86_GDT_ENTRY_32BIT_DS);
183 	load_ss(X86_GDT_ENTRY_32BIT_DS);
184 	load_es(X86_GDT_ENTRY_32BIT_DS);
185 	load_fs(X86_GDT_ENTRY_32BIT_DS);
186 	load_gs(X86_GDT_ENTRY_32BIT_DS);
187 }
188 #endif
189 
190 int __weak x86_cleanup_before_linux(void)
191 {
192 #ifdef CONFIG_BOOTSTAGE_STASH
193 	bootstage_stash((void *)CONFIG_BOOTSTAGE_STASH_ADDR,
194 			CONFIG_BOOTSTAGE_STASH_SIZE);
195 #endif
196 
197 	return 0;
198 }
199 
200 /*
201  * Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
202  * by the fact that they preserve the flags across the division of 5/2.
203  * PII and PPro exhibit this behavior too, but they have cpuid available.
204  */
205 
206 /*
207  * Perform the Cyrix 5/2 test. A Cyrix won't change
208  * the flags, while other 486 chips will.
209  */
210 static inline int test_cyrix_52div(void)
211 {
212 	unsigned int test;
213 
214 	__asm__ __volatile__(
215 	     "sahf\n\t"		/* clear flags (%eax = 0x0005) */
216 	     "div %b2\n\t"	/* divide 5 by 2 */
217 	     "lahf"		/* store flags into %ah */
218 	     : "=a" (test)
219 	     : "0" (5), "q" (2)
220 	     : "cc");
221 
222 	/* AH is 0x02 on Cyrix after the divide.. */
223 	return (unsigned char) (test >> 8) == 0x02;
224 }
225 
226 /*
227  *	Detect a NexGen CPU running without BIOS hypercode new enough
228  *	to have CPUID. (Thanks to Herbert Oppmann)
229  */
230 
231 static int deep_magic_nexgen_probe(void)
232 {
233 	int ret;
234 
235 	__asm__ __volatile__ (
236 		"	movw	$0x5555, %%ax\n"
237 		"	xorw	%%dx,%%dx\n"
238 		"	movw	$2, %%cx\n"
239 		"	divw	%%cx\n"
240 		"	movl	$0, %%eax\n"
241 		"	jnz	1f\n"
242 		"	movl	$1, %%eax\n"
243 		"1:\n"
244 		: "=a" (ret) : : "cx", "dx");
245 	return  ret;
246 }
247 
248 static bool has_cpuid(void)
249 {
250 	return flag_is_changeable_p(X86_EFLAGS_ID);
251 }
252 
253 static bool has_mtrr(void)
254 {
255 	return cpuid_edx(0x00000001) & (1 << 12) ? true : false;
256 }
257 
258 static int build_vendor_name(char *vendor_name)
259 {
260 	struct cpuid_result result;
261 	result = cpuid(0x00000000);
262 	unsigned int *name_as_ints = (unsigned int *)vendor_name;
263 
264 	name_as_ints[0] = result.ebx;
265 	name_as_ints[1] = result.edx;
266 	name_as_ints[2] = result.ecx;
267 
268 	return result.eax;
269 }
270 
271 static void identify_cpu(struct cpu_device_id *cpu)
272 {
273 	char vendor_name[16];
274 	int i;
275 
276 	vendor_name[0] = '\0'; /* Unset */
277 	cpu->device = 0; /* fix gcc 4.4.4 warning */
278 
279 	/* Find the id and vendor_name */
280 	if (!has_cpuid()) {
281 		/* Its a 486 if we can modify the AC flag */
282 		if (flag_is_changeable_p(X86_EFLAGS_AC))
283 			cpu->device = 0x00000400; /* 486 */
284 		else
285 			cpu->device = 0x00000300; /* 386 */
286 		if ((cpu->device == 0x00000400) && test_cyrix_52div()) {
287 			memcpy(vendor_name, "CyrixInstead", 13);
288 			/* If we ever care we can enable cpuid here */
289 		}
290 		/* Detect NexGen with old hypercode */
291 		else if (deep_magic_nexgen_probe())
292 			memcpy(vendor_name, "NexGenDriven", 13);
293 	}
294 	if (has_cpuid()) {
295 		int  cpuid_level;
296 
297 		cpuid_level = build_vendor_name(vendor_name);
298 		vendor_name[12] = '\0';
299 
300 		/* Intel-defined flags: level 0x00000001 */
301 		if (cpuid_level >= 0x00000001) {
302 			cpu->device = cpuid_eax(0x00000001);
303 		} else {
304 			/* Have CPUID level 0 only unheard of */
305 			cpu->device = 0x00000400;
306 		}
307 	}
308 	cpu->vendor = X86_VENDOR_UNKNOWN;
309 	for (i = 0; i < ARRAY_SIZE(x86_vendors); i++) {
310 		if (memcmp(vendor_name, x86_vendors[i].name, 12) == 0) {
311 			cpu->vendor = x86_vendors[i].vendor;
312 			break;
313 		}
314 	}
315 }
316 
317 static inline void get_fms(struct cpuinfo_x86 *c, uint32_t tfms)
318 {
319 	c->x86 = (tfms >> 8) & 0xf;
320 	c->x86_model = (tfms >> 4) & 0xf;
321 	c->x86_mask = tfms & 0xf;
322 	if (c->x86 == 0xf)
323 		c->x86 += (tfms >> 20) & 0xff;
324 	if (c->x86 >= 0x6)
325 		c->x86_model += ((tfms >> 16) & 0xF) << 4;
326 }
327 
328 int x86_cpu_init_f(void)
329 {
330 	const u32 em_rst = ~X86_CR0_EM;
331 	const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE;
332 
333 	if (ll_boot_init()) {
334 		/* initialize FPU, reset EM, set MP and NE */
335 		asm ("fninit\n" \
336 		"movl %%cr0, %%eax\n" \
337 		"andl %0, %%eax\n" \
338 		"orl  %1, %%eax\n" \
339 		"movl %%eax, %%cr0\n" \
340 		: : "i" (em_rst), "i" (mp_ne_set) : "eax");
341 	}
342 
343 	/* identify CPU via cpuid and store the decoded info into gd->arch */
344 	if (has_cpuid()) {
345 		struct cpu_device_id cpu;
346 		struct cpuinfo_x86 c;
347 
348 		identify_cpu(&cpu);
349 		get_fms(&c, cpu.device);
350 		gd->arch.x86 = c.x86;
351 		gd->arch.x86_vendor = cpu.vendor;
352 		gd->arch.x86_model = c.x86_model;
353 		gd->arch.x86_mask = c.x86_mask;
354 		gd->arch.x86_device = cpu.device;
355 
356 		gd->arch.has_mtrr = has_mtrr();
357 	}
358 	/* Don't allow PCI region 3 to use memory in the 2-4GB memory hole */
359 	gd->pci_ram_top = 0x80000000U;
360 
361 	/* Configure fixed range MTRRs for some legacy regions */
362 	if (gd->arch.has_mtrr) {
363 		u64 mtrr_cap;
364 
365 		mtrr_cap = native_read_msr(MTRR_CAP_MSR);
366 		if (mtrr_cap & MTRR_CAP_FIX) {
367 			/* Mark the VGA RAM area as uncacheable */
368 			native_write_msr(MTRR_FIX_16K_A0000_MSR,
369 					 MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE),
370 					 MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE));
371 
372 			/*
373 			 * Mark the PCI ROM area as cacheable to improve ROM
374 			 * execution performance.
375 			 */
376 			native_write_msr(MTRR_FIX_4K_C0000_MSR,
377 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
378 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
379 			native_write_msr(MTRR_FIX_4K_C8000_MSR,
380 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
381 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
382 			native_write_msr(MTRR_FIX_4K_D0000_MSR,
383 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
384 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
385 			native_write_msr(MTRR_FIX_4K_D8000_MSR,
386 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
387 					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
388 
389 			/* Enable the fixed range MTRRs */
390 			msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
391 		}
392 	}
393 
394 	return 0;
395 }
396 
397 void x86_enable_caches(void)
398 {
399 	unsigned long cr0;
400 
401 	cr0 = read_cr0();
402 	cr0 &= ~(X86_CR0_NW | X86_CR0_CD);
403 	write_cr0(cr0);
404 	wbinvd();
405 }
406 void enable_caches(void) __attribute__((weak, alias("x86_enable_caches")));
407 
408 void x86_disable_caches(void)
409 {
410 	unsigned long cr0;
411 
412 	cr0 = read_cr0();
413 	cr0 |= X86_CR0_NW | X86_CR0_CD;
414 	wbinvd();
415 	write_cr0(cr0);
416 	wbinvd();
417 }
418 void disable_caches(void) __attribute__((weak, alias("x86_disable_caches")));
419 
420 int x86_init_cache(void)
421 {
422 	enable_caches();
423 
424 	return 0;
425 }
426 int init_cache(void) __attribute__((weak, alias("x86_init_cache")));
427 
428 int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
429 {
430 	printf("resetting ...\n");
431 
432 	/* wait 50 ms */
433 	udelay(50000);
434 	disable_interrupts();
435 	reset_cpu(0);
436 
437 	/*NOTREACHED*/
438 	return 0;
439 }
440 
441 void  flush_cache(unsigned long dummy1, unsigned long dummy2)
442 {
443 	asm("wbinvd\n");
444 }
445 
446 __weak void reset_cpu(ulong addr)
447 {
448 	/* Do a hard reset through the chipset's reset control register */
449 	outb(SYS_RST | RST_CPU, PORT_RESET);
450 	for (;;)
451 		cpu_hlt();
452 }
453 
454 void x86_full_reset(void)
455 {
456 	outb(FULL_RST | SYS_RST | RST_CPU, PORT_RESET);
457 }
458 
459 int dcache_status(void)
460 {
461 	return !(read_cr0() & X86_CR0_CD);
462 }
463 
464 /* Define these functions to allow ehch-hcd to function */
465 void flush_dcache_range(unsigned long start, unsigned long stop)
466 {
467 }
468 
469 void invalidate_dcache_range(unsigned long start, unsigned long stop)
470 {
471 }
472 
473 void dcache_enable(void)
474 {
475 	enable_caches();
476 }
477 
478 void dcache_disable(void)
479 {
480 	disable_caches();
481 }
482 
483 void icache_enable(void)
484 {
485 }
486 
487 void icache_disable(void)
488 {
489 }
490 
491 int icache_status(void)
492 {
493 	return 1;
494 }
495 
496 void cpu_enable_paging_pae(ulong cr3)
497 {
498 	__asm__ __volatile__(
499 		/* Load the page table address */
500 		"movl	%0, %%cr3\n"
501 		/* Enable pae */
502 		"movl	%%cr4, %%eax\n"
503 		"orl	$0x00000020, %%eax\n"
504 		"movl	%%eax, %%cr4\n"
505 		/* Enable paging */
506 		"movl	%%cr0, %%eax\n"
507 		"orl	$0x80000000, %%eax\n"
508 		"movl	%%eax, %%cr0\n"
509 		:
510 		: "r" (cr3)
511 		: "eax");
512 }
513 
514 void cpu_disable_paging_pae(void)
515 {
516 	/* Turn off paging */
517 	__asm__ __volatile__ (
518 		/* Disable paging */
519 		"movl	%%cr0, %%eax\n"
520 		"andl	$0x7fffffff, %%eax\n"
521 		"movl	%%eax, %%cr0\n"
522 		/* Disable pae */
523 		"movl	%%cr4, %%eax\n"
524 		"andl	$0xffffffdf, %%eax\n"
525 		"movl	%%eax, %%cr4\n"
526 		:
527 		:
528 		: "eax");
529 }
530 
531 static bool can_detect_long_mode(void)
532 {
533 	return cpuid_eax(0x80000000) > 0x80000000UL;
534 }
535 
536 static bool has_long_mode(void)
537 {
538 	return cpuid_edx(0x80000001) & (1 << 29) ? true : false;
539 }
540 
541 int cpu_has_64bit(void)
542 {
543 	return has_cpuid() && can_detect_long_mode() &&
544 		has_long_mode();
545 }
546 
547 const char *cpu_vendor_name(int vendor)
548 {
549 	const char *name;
550 	name = "<invalid cpu vendor>";
551 	if ((vendor < (ARRAY_SIZE(x86_vendor_name))) &&
552 	    (x86_vendor_name[vendor] != 0))
553 		name = x86_vendor_name[vendor];
554 
555 	return name;
556 }
557 
558 char *cpu_get_name(char *name)
559 {
560 	unsigned int *name_as_ints = (unsigned int *)name;
561 	struct cpuid_result regs;
562 	char *ptr;
563 	int i;
564 
565 	/* This bit adds up to 48 bytes */
566 	for (i = 0; i < 3; i++) {
567 		regs = cpuid(0x80000002 + i);
568 		name_as_ints[i * 4 + 0] = regs.eax;
569 		name_as_ints[i * 4 + 1] = regs.ebx;
570 		name_as_ints[i * 4 + 2] = regs.ecx;
571 		name_as_ints[i * 4 + 3] = regs.edx;
572 	}
573 	name[CPU_MAX_NAME_LEN - 1] = '\0';
574 
575 	/* Skip leading spaces. */
576 	ptr = name;
577 	while (*ptr == ' ')
578 		ptr++;
579 
580 	return ptr;
581 }
582 
583 int default_print_cpuinfo(void)
584 {
585 	printf("CPU: %s, vendor %s, device %xh\n",
586 	       cpu_has_64bit() ? "x86_64" : "x86",
587 	       cpu_vendor_name(gd->arch.x86_vendor), gd->arch.x86_device);
588 
589 	return 0;
590 }
591 
592 #define PAGETABLE_SIZE		(6 * 4096)
593 
594 /**
595  * build_pagetable() - build a flat 4GiB page table structure for 64-bti mode
596  *
597  * @pgtable: Pointer to a 24iKB block of memory
598  */
599 static void build_pagetable(uint32_t *pgtable)
600 {
601 	uint i;
602 
603 	memset(pgtable, '\0', PAGETABLE_SIZE);
604 
605 	/* Level 4 needs a single entry */
606 	pgtable[0] = (uint32_t)&pgtable[1024] + 7;
607 
608 	/* Level 3 has one 64-bit entry for each GiB of memory */
609 	for (i = 0; i < 4; i++) {
610 		pgtable[1024 + i * 2] = (uint32_t)&pgtable[2048] +
611 							0x1000 * i + 7;
612 	}
613 
614 	/* Level 2 has 2048 64-bit entries, each repesenting 2MiB */
615 	for (i = 0; i < 2048; i++)
616 		pgtable[2048 + i * 2] = 0x183 + (i << 21UL);
617 }
618 
619 int cpu_jump_to_64bit(ulong setup_base, ulong target)
620 {
621 	uint32_t *pgtable;
622 
623 	pgtable = memalign(4096, PAGETABLE_SIZE);
624 	if (!pgtable)
625 		return -ENOMEM;
626 
627 	build_pagetable(pgtable);
628 	cpu_call64((ulong)pgtable, setup_base, target);
629 	free(pgtable);
630 
631 	return -EFAULT;
632 }
633 
634 void show_boot_progress(int val)
635 {
636 #if MIN_PORT80_KCLOCKS_DELAY
637 	/*
638 	 * Scale the time counter reading to avoid using 64 bit arithmetics.
639 	 * Can't use get_timer() here becuase it could be not yet
640 	 * initialized or even implemented.
641 	 */
642 	if (!gd->arch.tsc_prev) {
643 		gd->arch.tsc_base_kclocks = rdtsc() / 1000;
644 		gd->arch.tsc_prev = 0;
645 	} else {
646 		uint32_t now;
647 
648 		do {
649 			now = rdtsc() / 1000 - gd->arch.tsc_base_kclocks;
650 		} while (now < (gd->arch.tsc_prev + MIN_PORT80_KCLOCKS_DELAY));
651 		gd->arch.tsc_prev = now;
652 	}
653 #endif
654 	outb(val, POST_PORT);
655 }
656 
657 #ifndef CONFIG_SYS_COREBOOT
658 int last_stage_init(void)
659 {
660 	write_tables();
661 
662 	return 0;
663 }
664 #endif
665 
666 #ifdef CONFIG_SMP
667 static int enable_smis(struct udevice *cpu, void *unused)
668 {
669 	return 0;
670 }
671 
672 static struct mp_flight_record mp_steps[] = {
673 	MP_FR_BLOCK_APS(mp_init_cpu, NULL, mp_init_cpu, NULL),
674 	/* Wait for APs to finish initialization before proceeding */
675 	MP_FR_BLOCK_APS(NULL, NULL, enable_smis, NULL),
676 };
677 
678 static int x86_mp_init(void)
679 {
680 	struct mp_params mp_params;
681 
682 	mp_params.parallel_microcode_load = 0,
683 	mp_params.flight_plan = &mp_steps[0];
684 	mp_params.num_records = ARRAY_SIZE(mp_steps);
685 	mp_params.microcode_pointer = 0;
686 
687 	if (mp_init(&mp_params)) {
688 		printf("Warning: MP init failure\n");
689 		return -EIO;
690 	}
691 
692 	return 0;
693 }
694 #endif
695 
696 __weak int x86_init_cpus(void)
697 {
698 #ifdef CONFIG_SMP
699 	debug("Init additional CPUs\n");
700 	x86_mp_init();
701 #else
702 	struct udevice *dev;
703 
704 	/*
705 	 * This causes the cpu-x86 driver to be probed.
706 	 * We don't check return value here as we want to allow boards
707 	 * which have not been converted to use cpu uclass driver to boot.
708 	 */
709 	uclass_first_device(UCLASS_CPU, &dev);
710 #endif
711 
712 	return 0;
713 }
714 
715 int cpu_init_r(void)
716 {
717 	if (ll_boot_init())
718 		return x86_init_cpus();
719 
720 	return 0;
721 }
722