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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 
     22 /*
     23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
     24  * Use is subject to license terms.
     25  */
     26 
     27 #include <sys/types.h>
     28 #include <sys/thread.h>
     29 #include <sys/cpuvar.h>
     30 #include <sys/t_lock.h>
     31 #include <sys/param.h>
     32 #include <sys/proc.h>
     33 #include <sys/disp.h>
     34 #include <sys/class.h>
     35 #include <sys/cmn_err.h>
     36 #include <sys/debug.h>
     37 #include <sys/asm_linkage.h>
     38 #include <sys/x_call.h>
     39 #include <sys/systm.h>
     40 #include <sys/var.h>
     41 #include <sys/vtrace.h>
     42 #include <vm/hat.h>
     43 #include <vm/as.h>
     44 #include <vm/seg_kmem.h>
     45 #include <vm/seg_kp.h>
     46 #include <sys/segments.h>
     47 #include <sys/kmem.h>
     48 #include <sys/stack.h>
     49 #include <sys/smp_impldefs.h>
     50 #include <sys/x86_archext.h>
     51 #include <sys/machsystm.h>
     52 #include <sys/traptrace.h>
     53 #include <sys/clock.h>
     54 #include <sys/cpc_impl.h>
     55 #include <sys/pg.h>
     56 #include <sys/cmt.h>
     57 #include <sys/dtrace.h>
     58 #include <sys/archsystm.h>
     59 #include <sys/fp.h>
     60 #include <sys/reboot.h>
     61 #include <sys/kdi_machimpl.h>
     62 #include <vm/hat_i86.h>
     63 #include <sys/memnode.h>
     64 #include <sys/pci_cfgspace.h>
     65 #include <sys/mach_mmu.h>
     66 #include <sys/sysmacros.h>
     67 #if defined(__xpv)
     68 #include <sys/hypervisor.h>
     69 #endif
     70 #include <sys/cpu_module.h>
     71 
     72 struct cpu	cpus[1];			/* CPU data */
     73 struct cpu	*cpu[NCPU] = {&cpus[0]};	/* pointers to all CPUs */
     74 cpu_core_t	cpu_core[NCPU];			/* cpu_core structures */
     75 
     76 /*
     77  * Useful for disabling MP bring-up on a MP capable system.
     78  */
     79 int use_mp = 1;
     80 
     81 /*
     82  * to be set by a PSM to indicate what cpus
     83  * are sitting around on the system.
     84  */
     85 cpuset_t mp_cpus;
     86 
     87 /*
     88  * This variable is used by the hat layer to decide whether or not
     89  * critical sections are needed to prevent race conditions.  For sun4m,
     90  * this variable is set once enough MP initialization has been done in
     91  * order to allow cross calls.
     92  */
     93 int flushes_require_xcalls;
     94 
     95 cpuset_t cpu_ready_set;		/* initialized in startup() */
     96 
     97 static 	void	mp_startup(void);
     98 
     99 static void cpu_sep_enable(void);
    100 static void cpu_sep_disable(void);
    101 static void cpu_asysc_enable(void);
    102 static void cpu_asysc_disable(void);
    103 
    104 /*
    105  * Init CPU info - get CPU type info for processor_info system call.
    106  */
    107 void
    108 init_cpu_info(struct cpu *cp)
    109 {
    110 	processor_info_t *pi = &cp->cpu_type_info;
    111 	char buf[CPU_IDSTRLEN];
    112 
    113 	/*
    114 	 * Get clock-frequency property for the CPU.
    115 	 */
    116 	pi->pi_clock = cpu_freq;
    117 
    118 	/*
    119 	 * Current frequency in Hz.
    120 	 */
    121 	cp->cpu_curr_clock = cpu_freq_hz;
    122 
    123 	/*
    124 	 * Supported frequencies.
    125 	 */
    126 	if (cp->cpu_supp_freqs == NULL) {
    127 		cpu_set_supp_freqs(cp, NULL);
    128 	}
    129 
    130 	(void) strcpy(pi->pi_processor_type, "i386");
    131 	if (fpu_exists)
    132 		(void) strcpy(pi->pi_fputypes, "i387 compatible");
    133 
    134 	(void) cpuid_getidstr(cp, buf, sizeof (buf));
    135 
    136 	cp->cpu_idstr = kmem_alloc(strlen(buf) + 1, KM_SLEEP);
    137 	(void) strcpy(cp->cpu_idstr, buf);
    138 
    139 	(void) cpuid_getbrandstr(cp, buf, sizeof (buf));
    140 	cp->cpu_brandstr = kmem_alloc(strlen(buf) + 1, KM_SLEEP);
    141 	(void) strcpy(cp->cpu_brandstr, buf);
    142 }
    143 
    144 /*
    145  * Configure syscall support on this CPU.
    146  */
    147 /*ARGSUSED*/
    148 void
    149 init_cpu_syscall(struct cpu *cp)
    150 {
    151 	kpreempt_disable();
    152 
    153 #if defined(__amd64)
    154 	if ((x86_feature & (X86_MSR | X86_ASYSC)) == (X86_MSR | X86_ASYSC)) {
    155 
    156 #if !defined(__lint)
    157 		/*
    158 		 * The syscall instruction imposes a certain ordering on
    159 		 * segment selectors, so we double-check that ordering
    160 		 * here.
    161 		 */
    162 		ASSERT(KDS_SEL == KCS_SEL + 8);
    163 		ASSERT(UDS_SEL == U32CS_SEL + 8);
    164 		ASSERT(UCS_SEL == U32CS_SEL + 16);
    165 #endif
    166 		/*
    167 		 * Turn syscall/sysret extensions on.
    168 		 */
    169 		cpu_asysc_enable();
    170 
    171 		/*
    172 		 * Program the magic registers ..
    173 		 */
    174 		wrmsr(MSR_AMD_STAR,
    175 		    ((uint64_t)(U32CS_SEL << 16 | KCS_SEL)) << 32);
    176 		wrmsr(MSR_AMD_LSTAR, (uint64_t)(uintptr_t)sys_syscall);
    177 		wrmsr(MSR_AMD_CSTAR, (uint64_t)(uintptr_t)sys_syscall32);
    178 
    179 		/*
    180 		 * This list of flags is masked off the incoming
    181 		 * %rfl when we enter the kernel.
    182 		 */
    183 		wrmsr(MSR_AMD_SFMASK, (uint64_t)(uintptr_t)(PS_IE | PS_T));
    184 	}
    185 #endif
    186 
    187 	/*
    188 	 * On 32-bit kernels, we use sysenter/sysexit because it's too
    189 	 * hard to use syscall/sysret, and it is more portable anyway.
    190 	 *
    191 	 * On 64-bit kernels on Nocona machines, the 32-bit syscall
    192 	 * variant isn't available to 32-bit applications, but sysenter is.
    193 	 */
    194 	if ((x86_feature & (X86_MSR | X86_SEP)) == (X86_MSR | X86_SEP)) {
    195 
    196 #if !defined(__lint)
    197 		/*
    198 		 * The sysenter instruction imposes a certain ordering on
    199 		 * segment selectors, so we double-check that ordering
    200 		 * here. See "sysenter" in Intel document 245471-012, "IA-32
    201 		 * Intel Architecture Software Developer's Manual Volume 2:
    202 		 * Instruction Set Reference"
    203 		 */
    204 		ASSERT(KDS_SEL == KCS_SEL + 8);
    205 
    206 		ASSERT32(UCS_SEL == ((KCS_SEL + 16) | 3));
    207 		ASSERT32(UDS_SEL == UCS_SEL + 8);
    208 
    209 		ASSERT64(U32CS_SEL == ((KCS_SEL + 16) | 3));
    210 		ASSERT64(UDS_SEL == U32CS_SEL + 8);
    211 #endif
    212 
    213 		cpu_sep_enable();
    214 
    215 		/*
    216 		 * resume() sets this value to the base of the threads stack
    217 		 * via a context handler.
    218 		 */
    219 		wrmsr(MSR_INTC_SEP_ESP, 0);
    220 		wrmsr(MSR_INTC_SEP_EIP, (uint64_t)(uintptr_t)sys_sysenter);
    221 	}
    222 
    223 	kpreempt_enable();
    224 }
    225 
    226 /*
    227  * Multiprocessor initialization.
    228  *
    229  * Allocate and initialize the cpu structure, TRAPTRACE buffer, and the
    230  * startup and idle threads for the specified CPU.
    231  */
    232 struct cpu *
    233 mp_startup_init(int cpun)
    234 {
    235 	struct cpu *cp;
    236 	kthread_id_t tp;
    237 	caddr_t	sp;
    238 	proc_t *procp;
    239 #if !defined(__xpv)
    240 	extern int idle_cpu_prefer_mwait;
    241 	extern void cpu_idle_mwait();
    242 #endif
    243 	extern void idle();
    244 	extern void cpu_idle();
    245 
    246 #ifdef TRAPTRACE
    247 	trap_trace_ctl_t *ttc = &trap_trace_ctl[cpun];
    248 #endif
    249 
    250 	ASSERT(cpun < NCPU && cpu[cpun] == NULL);
    251 
    252 	cp = kmem_zalloc(sizeof (*cp), KM_SLEEP);
    253 #if !defined(__xpv)
    254 	if ((x86_feature & X86_MWAIT) && idle_cpu_prefer_mwait) {
    255 		cp->cpu_m.mcpu_mwait = cpuid_mwait_alloc(CPU);
    256 		cp->cpu_m.mcpu_idle_cpu = cpu_idle_mwait;
    257 	} else
    258 #endif
    259 		cp->cpu_m.mcpu_idle_cpu = cpu_idle;
    260 
    261 	procp = curthread->t_procp;
    262 
    263 	mutex_enter(&cpu_lock);
    264 	/*
    265 	 * Initialize the dispatcher first.
    266 	 */
    267 	disp_cpu_init(cp);
    268 	mutex_exit(&cpu_lock);
    269 
    270 	cpu_vm_data_init(cp);
    271 
    272 	/*
    273 	 * Allocate and initialize the startup thread for this CPU.
    274 	 * Interrupt and process switch stacks get allocated later
    275 	 * when the CPU starts running.
    276 	 */
    277 	tp = thread_create(NULL, 0, NULL, NULL, 0, procp,
    278 	    TS_STOPPED, maxclsyspri);
    279 
    280 	/*
    281 	 * Set state to TS_ONPROC since this thread will start running
    282 	 * as soon as the CPU comes online.
    283 	 *
    284 	 * All the other fields of the thread structure are setup by
    285 	 * thread_create().
    286 	 */
    287 	THREAD_ONPROC(tp, cp);
    288 	tp->t_preempt = 1;
    289 	tp->t_bound_cpu = cp;
    290 	tp->t_affinitycnt = 1;
    291 	tp->t_cpu = cp;
    292 	tp->t_disp_queue = cp->cpu_disp;
    293 
    294 	/*
    295 	 * Setup thread to start in mp_startup.
    296 	 */
    297 	sp = tp->t_stk;
    298 	tp->t_pc = (uintptr_t)mp_startup;
    299 	tp->t_sp = (uintptr_t)(sp - MINFRAME);
    300 #if defined(__amd64)
    301 	tp->t_sp -= STACK_ENTRY_ALIGN;		/* fake a call */
    302 #endif
    303 
    304 	cp->cpu_id = cpun;
    305 	cp->cpu_self = cp;
    306 	cp->cpu_thread = tp;
    307 	cp->cpu_lwp = NULL;
    308 	cp->cpu_dispthread = tp;
    309 	cp->cpu_dispatch_pri = DISP_PRIO(tp);
    310 
    311 	/*
    312 	 * cpu_base_spl must be set explicitly here to prevent any blocking
    313 	 * operations in mp_startup from causing the spl of the cpu to drop
    314 	 * to 0 (allowing device interrupts before we're ready) in resume().
    315 	 * cpu_base_spl MUST remain at LOCK_LEVEL until the cpu is CPU_READY.
    316 	 * As an extra bit of security on DEBUG kernels, this is enforced with
    317 	 * an assertion in mp_startup() -- before cpu_base_spl is set to its
    318 	 * proper value.
    319 	 */
    320 	cp->cpu_base_spl = ipltospl(LOCK_LEVEL);
    321 
    322 	/*
    323 	 * Now, initialize per-CPU idle thread for this CPU.
    324 	 */
    325 	tp = thread_create(NULL, PAGESIZE, idle, NULL, 0, procp, TS_ONPROC, -1);
    326 
    327 	cp->cpu_idle_thread = tp;
    328 
    329 	tp->t_preempt = 1;
    330 	tp->t_bound_cpu = cp;
    331 	tp->t_affinitycnt = 1;
    332 	tp->t_cpu = cp;
    333 	tp->t_disp_queue = cp->cpu_disp;
    334 
    335 	/*
    336 	 * Bootstrap the CPU's PG data
    337 	 */
    338 	pg_cpu_bootstrap(cp);
    339 
    340 	/*
    341 	 * Perform CPC initialization on the new CPU.
    342 	 */
    343 	kcpc_hw_init(cp);
    344 
    345 	/*
    346 	 * Allocate virtual addresses for cpu_caddr1 and cpu_caddr2
    347 	 * for each CPU.
    348 	 */
    349 	setup_vaddr_for_ppcopy(cp);
    350 
    351 	/*
    352 	 * Allocate page for new GDT and initialize from current GDT.
    353 	 */
    354 #if !defined(__lint)
    355 	ASSERT((sizeof (*cp->cpu_gdt) * NGDT) <= PAGESIZE);
    356 #endif
    357 	cp->cpu_gdt = kmem_zalloc(PAGESIZE, KM_SLEEP);
    358 	bcopy(CPU->cpu_gdt, cp->cpu_gdt, (sizeof (*cp->cpu_gdt) * NGDT));
    359 
    360 #if defined(__i386)
    361 	/*
    362 	 * setup kernel %gs.
    363 	 */
    364 	set_usegd(&cp->cpu_gdt[GDT_GS], cp, sizeof (struct cpu) -1, SDT_MEMRWA,
    365 	    SEL_KPL, 0, 1);
    366 #endif
    367 
    368 	/*
    369 	 * If we have more than one node, each cpu gets a copy of IDT
    370 	 * local to its node. If this is a Pentium box, we use cpu 0's
    371 	 * IDT. cpu 0's IDT has been made read-only to workaround the
    372 	 * cmpxchgl register bug
    373 	 */
    374 	if (system_hardware.hd_nodes && x86_type != X86_TYPE_P5) {
    375 #if !defined(__lint)
    376 		ASSERT((sizeof (*CPU->cpu_idt) * NIDT) <= PAGESIZE);
    377 #endif
    378 		cp->cpu_idt = kmem_zalloc(PAGESIZE, KM_SLEEP);
    379 		bcopy(CPU->cpu_idt, cp->cpu_idt, PAGESIZE);
    380 	} else {
    381 		cp->cpu_idt = CPU->cpu_idt;
    382 	}
    383 
    384 	/*
    385 	 * Get interrupt priority data from cpu 0.
    386 	 */
    387 	cp->cpu_pri_data = CPU->cpu_pri_data;
    388 
    389 	/*
    390 	 * alloc space for cpuid info
    391 	 */
    392 	cpuid_alloc_space(cp);
    393 
    394 	/*
    395 	 * alloc space for ucode_info
    396 	 */
    397 	ucode_alloc_space(cp);
    398 	xc_init_cpu(cp);
    399 	hat_cpu_online(cp);
    400 
    401 #ifdef TRAPTRACE
    402 	/*
    403 	 * If this is a TRAPTRACE kernel, allocate TRAPTRACE buffers
    404 	 */
    405 	ttc->ttc_first = (uintptr_t)kmem_zalloc(trap_trace_bufsize, KM_SLEEP);
    406 	ttc->ttc_next = ttc->ttc_first;
    407 	ttc->ttc_limit = ttc->ttc_first + trap_trace_bufsize;
    408 #endif
    409 	/*
    410 	 * Record that we have another CPU.
    411 	 */
    412 	mutex_enter(&cpu_lock);
    413 	/*
    414 	 * Initialize the interrupt threads for this CPU
    415 	 */
    416 	cpu_intr_alloc(cp, NINTR_THREADS);
    417 	/*
    418 	 * Add CPU to list of available CPUs.  It'll be on the active list
    419 	 * after mp_startup().
    420 	 */
    421 	cpu_add_unit(cp);
    422 	mutex_exit(&cpu_lock);
    423 
    424 	return (cp);
    425 }
    426 
    427 /*
    428  * Undo what was done in mp_startup_init
    429  */
    430 static void
    431 mp_startup_fini(struct cpu *cp, int error)
    432 {
    433 	mutex_enter(&cpu_lock);
    434 
    435 	/*
    436 	 * Remove the CPU from the list of available CPUs.
    437 	 */
    438 	cpu_del_unit(cp->cpu_id);
    439 
    440 	if (error == ETIMEDOUT) {
    441 		/*
    442 		 * The cpu was started, but never *seemed* to run any
    443 		 * code in the kernel; it's probably off spinning in its
    444 		 * own private world, though with potential references to
    445 		 * our kmem-allocated IDTs and GDTs (for example).
    446 		 *
    447 		 * Worse still, it may actually wake up some time later,
    448 		 * so rather than guess what it might or might not do, we
    449 		 * leave the fundamental data structures intact.
    450 		 */
    451 		cp->cpu_flags = 0;
    452 		mutex_exit(&cpu_lock);
    453 		return;
    454 	}
    455 
    456 	/*
    457 	 * At this point, the only threads bound to this CPU should
    458 	 * special per-cpu threads: it's idle thread, it's pause threads,
    459 	 * and it's interrupt threads.  Clean these up.
    460 	 */
    461 	cpu_destroy_bound_threads(cp);
    462 	cp->cpu_idle_thread = NULL;
    463 
    464 	/*
    465 	 * Free the interrupt stack.
    466 	 */
    467 	segkp_release(segkp,
    468 	    cp->cpu_intr_stack - (INTR_STACK_SIZE - SA(MINFRAME)));
    469 
    470 	mutex_exit(&cpu_lock);
    471 
    472 #ifdef TRAPTRACE
    473 	/*
    474 	 * Discard the trap trace buffer
    475 	 */
    476 	{
    477 		trap_trace_ctl_t *ttc = &trap_trace_ctl[cp->cpu_id];
    478 
    479 		kmem_free((void *)ttc->ttc_first, trap_trace_bufsize);
    480 		ttc->ttc_first = NULL;
    481 	}
    482 #endif
    483 
    484 	hat_cpu_offline(cp);
    485 
    486 	cpuid_free_space(cp);
    487 
    488 	ucode_free_space(cp);
    489 
    490 	if (cp->cpu_idt != CPU->cpu_idt)
    491 		kmem_free(cp->cpu_idt, PAGESIZE);
    492 	cp->cpu_idt = NULL;
    493 
    494 	kmem_free(cp->cpu_gdt, PAGESIZE);
    495 	cp->cpu_gdt = NULL;
    496 
    497 	teardown_vaddr_for_ppcopy(cp);
    498 
    499 	kcpc_hw_fini(cp);
    500 
    501 	cp->cpu_dispthread = NULL;
    502 	cp->cpu_thread = NULL;	/* discarded by cpu_destroy_bound_threads() */
    503 
    504 	cpu_vm_data_destroy(cp);
    505 
    506 	mutex_enter(&cpu_lock);
    507 	disp_cpu_fini(cp);
    508 	mutex_exit(&cpu_lock);
    509 
    510 #if !defined(__xpv)
    511 	if (cp->cpu_m.mcpu_mwait != NULL)
    512 		cpuid_mwait_free(cp);
    513 #endif
    514 	kmem_free(cp, sizeof (*cp));
    515 }
    516 
    517 /*
    518  * Apply workarounds for known errata, and warn about those that are absent.
    519  *
    520  * System vendors occasionally create configurations which contain different
    521  * revisions of the CPUs that are almost but not exactly the same.  At the
    522  * time of writing, this meant that their clock rates were the same, their
    523  * feature sets were the same, but the required workaround were -not-
    524  * necessarily the same.  So, this routine is invoked on -every- CPU soon
    525  * after starting to make sure that the resulting system contains the most
    526  * pessimal set of workarounds needed to cope with *any* of the CPUs in the
    527  * system.
    528  *
    529  * workaround_errata is invoked early in mlsetup() for CPU 0, and in
    530  * mp_startup() for all slave CPUs. Slaves process workaround_errata prior
    531  * to acknowledging their readiness to the master, so this routine will
    532  * never be executed by multiple CPUs in parallel, thus making updates to
    533  * global data safe.
    534  *
    535  * These workarounds are based on Rev 3.57 of the Revision Guide for
    536  * AMD Athlon(tm) 64 and AMD Opteron(tm) Processors, August 2005.
    537  */
    538 
    539 #if defined(OPTERON_ERRATUM_88)
    540 int opteron_erratum_88;		/* if non-zero -> at least one cpu has it */
    541 #endif
    542 
    543 #if defined(OPTERON_ERRATUM_91)
    544 int opteron_erratum_91;		/* if non-zero -> at least one cpu has it */
    545 #endif
    546 
    547 #if defined(OPTERON_ERRATUM_93)
    548 int opteron_erratum_93;		/* if non-zero -> at least one cpu has it */
    549 #endif
    550 
    551 #if defined(OPTERON_ERRATUM_95)
    552 int opteron_erratum_95;		/* if non-zero -> at least one cpu has it */
    553 #endif
    554 
    555 #if defined(OPTERON_ERRATUM_100)
    556 int opteron_erratum_100;	/* if non-zero -> at least one cpu has it */
    557 #endif
    558 
    559 #if defined(OPTERON_ERRATUM_108)
    560 int opteron_erratum_108;	/* if non-zero -> at least one cpu has it */
    561 #endif
    562 
    563 #if defined(OPTERON_ERRATUM_109)
    564 int opteron_erratum_109;	/* if non-zero -> at least one cpu has it */
    565 #endif
    566 
    567 #if defined(OPTERON_ERRATUM_121)
    568 int opteron_erratum_121;	/* if non-zero -> at least one cpu has it */
    569 #endif
    570 
    571 #if defined(OPTERON_ERRATUM_122)
    572 int opteron_erratum_122;	/* if non-zero -> at least one cpu has it */
    573 #endif
    574 
    575 #if defined(OPTERON_ERRATUM_123)
    576 int opteron_erratum_123;	/* if non-zero -> at least one cpu has it */
    577 #endif
    578 
    579 #if defined(OPTERON_ERRATUM_131)
    580 int opteron_erratum_131;	/* if non-zero -> at least one cpu has it */
    581 #endif
    582 
    583 #if defined(OPTERON_WORKAROUND_6336786)
    584 int opteron_workaround_6336786;	/* non-zero -> WA relevant and applied */
    585 int opteron_workaround_6336786_UP = 0;	/* Not needed for UP */
    586 #endif
    587 
    588 #if defined(OPTERON_WORKAROUND_6323525)
    589 int opteron_workaround_6323525;	/* if non-zero -> at least one cpu has it */
    590 #endif
    591 
    592 #if defined(OPTERON_ERRATUM_298)
    593 int opteron_erratum_298;
    594 #endif
    595 
    596 static void
    597 workaround_warning(cpu_t *cp, uint_t erratum)
    598 {
    599 	cmn_err(CE_WARN, "cpu%d: no workaround for erratum %u",
    600 	    cp->cpu_id, erratum);
    601 }
    602 
    603 static void
    604 workaround_applied(uint_t erratum)
    605 {
    606 	if (erratum > 1000000)
    607 		cmn_err(CE_CONT, "?workaround applied for cpu issue #%d\n",
    608 		    erratum);
    609 	else
    610 		cmn_err(CE_CONT, "?workaround applied for cpu erratum #%d\n",
    611 		    erratum);
    612 }
    613 
    614 static void
    615 msr_warning(cpu_t *cp, const char *rw, uint_t msr, int error)
    616 {
    617 	cmn_err(CE_WARN, "cpu%d: couldn't %smsr 0x%x, error %d",
    618 	    cp->cpu_id, rw, msr, error);
    619 }
    620 
    621 /*
    622  * Determine the number of nodes in a Hammer / Greyhound / Griffin family
    623  * system.
    624  */
    625 static uint_t
    626 opteron_get_nnodes(void)
    627 {
    628 	static uint_t nnodes = 0;
    629 
    630 	if (nnodes == 0) {
    631 #ifdef	DEBUG
    632 		uint_t family;
    633 
    634 		/*
    635 		 * This routine uses a PCI config space based mechanism
    636 		 * for retrieving the number of nodes in the system.
    637 		 * Device 24, function 0, offset 0x60 as used here is not
    638 		 * AMD processor architectural, and may not work on processor
    639 		 * families other than those listed below.
    640 		 *
    641 		 * Callers of this routine must ensure that we're running on
    642 		 * a processor which supports this mechanism.
    643 		 * The assertion below is meant to catch calls on unsupported
    644 		 * processors.
    645 		 */
    646 		family = cpuid_getfamily(CPU);
    647 		ASSERT(family == 0xf || family == 0x10 || family == 0x11);
    648 #endif	/* DEBUG */
    649 
    650 		/*
    651 		 * Obtain the number of nodes in the system from
    652 		 * bits [6:4] of the Node ID register on node 0.
    653 		 *
    654 		 * The actual node count is NodeID[6:4] + 1
    655 		 *
    656 		 * The Node ID register is accessed via function 0,
    657 		 * offset 0x60. Node 0 is device 24.
    658 		 */
    659 		nnodes = ((pci_getl_func(0, 24, 0, 0x60) & 0x70) >> 4) + 1;
    660 	}
    661 	return (nnodes);
    662 }
    663 
    664 uint_t
    665 do_erratum_298(struct cpu *cpu)
    666 {
    667 	static int	osvwrc = -3;
    668 	extern int	osvw_opteron_erratum(cpu_t *, uint_t);
    669 
    670 	/*
    671 	 * L2 Eviction May Occur During Processor Operation To Set
    672 	 * Accessed or Dirty Bit.
    673 	 */
    674 	if (osvwrc == -3) {
    675 		osvwrc = osvw_opteron_erratum(cpu, 298);
    676 	} else {
    677 		/* osvw return codes should be consistent for all cpus */
    678 		ASSERT(osvwrc == osvw_opteron_erratum(cpu, 298));
    679 	}
    680 
    681 	switch (osvwrc) {
    682 	case 0:		/* erratum is not present: do nothing */
    683 		break;
    684 	case 1:		/* erratum is present: BIOS workaround applied */
    685 		/*
    686 		 * check if workaround is actually in place and issue warning
    687 		 * if not.
    688 		 */
    689 		if (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
    690 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0)) {
    691 #if defined(OPTERON_ERRATUM_298)
    692 			opteron_erratum_298++;
    693 #else
    694 			workaround_warning(cpu, 298);
    695 			return (1);
    696 #endif
    697 		}
    698 		break;
    699 	case -1:	/* cannot determine via osvw: check cpuid */
    700 		if ((cpuid_opteron_erratum(cpu, 298) > 0) &&
    701 		    (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
    702 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0))) {
    703 #if defined(OPTERON_ERRATUM_298)
    704 			opteron_erratum_298++;
    705 #else
    706 			workaround_warning(cpu, 298);
    707 			return (1);
    708 #endif
    709 		}
    710 		break;
    711 	}
    712 	return (0);
    713 }
    714 
    715 uint_t
    716 workaround_errata(struct cpu *cpu)
    717 {
    718 	uint_t missing = 0;
    719 
    720 	ASSERT(cpu == CPU);
    721 
    722 	/*LINTED*/
    723 	if (cpuid_opteron_erratum(cpu, 88) > 0) {
    724 		/*
    725 		 * SWAPGS May Fail To Read Correct GS Base
    726 		 */
    727 #if defined(OPTERON_ERRATUM_88)
    728 		/*
    729 		 * The workaround is an mfence in the relevant assembler code
    730 		 */
    731 		opteron_erratum_88++;
    732 #else
    733 		workaround_warning(cpu, 88);
    734 		missing++;
    735 #endif
    736 	}
    737 
    738 	if (cpuid_opteron_erratum(cpu, 91) > 0) {
    739 		/*
    740 		 * Software Prefetches May Report A Page Fault
    741 		 */
    742 #if defined(OPTERON_ERRATUM_91)
    743 		/*
    744 		 * fix is in trap.c
    745 		 */
    746 		opteron_erratum_91++;
    747 #else
    748 		workaround_warning(cpu, 91);
    749 		missing++;
    750 #endif
    751 	}
    752 
    753 	if (cpuid_opteron_erratum(cpu, 93) > 0) {
    754 		/*
    755 		 * RSM Auto-Halt Restart Returns to Incorrect RIP
    756 		 */
    757 #if defined(OPTERON_ERRATUM_93)
    758 		/*
    759 		 * fix is in trap.c
    760 		 */
    761 		opteron_erratum_93++;
    762 #else
    763 		workaround_warning(cpu, 93);
    764 		missing++;
    765 #endif
    766 	}
    767 
    768 	/*LINTED*/
    769 	if (cpuid_opteron_erratum(cpu, 95) > 0) {
    770 		/*
    771 		 * RET Instruction May Return to Incorrect EIP
    772 		 */
    773 #if defined(OPTERON_ERRATUM_95)
    774 #if defined(_LP64)
    775 		/*
    776 		 * Workaround this by ensuring that 32-bit user code and
    777 		 * 64-bit kernel code never occupy the same address
    778 		 * range mod 4G.
    779 		 */
    780 		if (_userlimit32 > 0xc0000000ul)
    781 			*(uintptr_t *)&_userlimit32 = 0xc0000000ul;
    782 
    783 		/*LINTED*/
    784 		ASSERT((uint32_t)COREHEAP_BASE == 0xc0000000u);
    785 		opteron_erratum_95++;
    786 #endif	/* _LP64 */
    787 #else
    788 		workaround_warning(cpu, 95);
    789 		missing++;
    790 #endif
    791 	}
    792 
    793 	if (cpuid_opteron_erratum(cpu, 100) > 0) {
    794 		/*
    795 		 * Compatibility Mode Branches Transfer to Illegal Address
    796 		 */
    797 #if defined(OPTERON_ERRATUM_100)
    798 		/*
    799 		 * fix is in trap.c
    800 		 */
    801 		opteron_erratum_100++;
    802 #else
    803 		workaround_warning(cpu, 100);
    804 		missing++;
    805 #endif
    806 	}
    807 
    808 	/*LINTED*/
    809 	if (cpuid_opteron_erratum(cpu, 108) > 0) {
    810 		/*
    811 		 * CPUID Instruction May Return Incorrect Model Number In
    812 		 * Some Processors
    813 		 */
    814 #if defined(OPTERON_ERRATUM_108)
    815 		/*
    816 		 * (Our cpuid-handling code corrects the model number on
    817 		 * those processors)
    818 		 */
    819 #else
    820 		workaround_warning(cpu, 108);
    821 		missing++;
    822 #endif
    823 	}
    824 
    825 	/*LINTED*/
    826 	if (cpuid_opteron_erratum(cpu, 109) > 0) do {
    827 		/*
    828 		 * Certain Reverse REP MOVS May Produce Unpredictable Behavior
    829 		 */
    830 #if defined(OPTERON_ERRATUM_109)
    831 		/*
    832 		 * The "workaround" is to print a warning to upgrade the BIOS
    833 		 */
    834 		uint64_t value;
    835 		const uint_t msr = MSR_AMD_PATCHLEVEL;
    836 		int err;
    837 
    838 		if ((err = checked_rdmsr(msr, &value)) != 0) {
    839 			msr_warning(cpu, "rd", msr, err);
    840 			workaround_warning(cpu, 109);
    841 			missing++;
    842 		}
    843 		if (value == 0)
    844 			opteron_erratum_109++;
    845 #else
    846 		workaround_warning(cpu, 109);
    847 		missing++;
    848 #endif
    849 	/*CONSTANTCONDITION*/
    850 	} while (0);
    851 
    852 	/*LINTED*/
    853 	if (cpuid_opteron_erratum(cpu, 121) > 0) {
    854 		/*
    855 		 * Sequential Execution Across Non_Canonical Boundary Caused
    856 		 * Processor Hang
    857 		 */
    858 #if defined(OPTERON_ERRATUM_121)
    859 #if defined(_LP64)
    860 		/*
    861 		 * Erratum 121 is only present in long (64 bit) mode.
    862 		 * Workaround is to include the page immediately before the
    863 		 * va hole to eliminate the possibility of system hangs due to
    864 		 * sequential execution across the va hole boundary.
    865 		 */
    866 		if (opteron_erratum_121)
    867 			opteron_erratum_121++;
    868 		else {
    869 			if (hole_start) {
    870 				hole_start -= PAGESIZE;
    871 			} else {
    872 				/*
    873 				 * hole_start not yet initialized by
    874 				 * mmu_init. Initialize hole_start
    875 				 * with value to be subtracted.
    876 				 */
    877 				hole_start = PAGESIZE;
    878 			}
    879 			opteron_erratum_121++;
    880 		}
    881 #endif	/* _LP64 */
    882 #else
    883 		workaround_warning(cpu, 121);
    884 		missing++;
    885 #endif
    886 	}
    887 
    888 	/*LINTED*/
    889 	if (cpuid_opteron_erratum(cpu, 122) > 0) do {
    890 		/*
    891 		 * TLB Flush Filter May Cause Coherency Problem in
    892 		 * Multiprocessor Systems
    893 		 */
    894 #if defined(OPTERON_ERRATUM_122)
    895 		uint64_t value;
    896 		const uint_t msr = MSR_AMD_HWCR;
    897 		int error;
    898 
    899 		/*
    900 		 * Erratum 122 is only present in MP configurations (multi-core
    901 		 * or multi-processor).
    902 		 */
    903 #if defined(__xpv)
    904 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    905 			break;
    906 		if (!opteron_erratum_122 && xpv_nr_phys_cpus() == 1)
    907 			break;
    908 #else
    909 		if (!opteron_erratum_122 && opteron_get_nnodes() == 1 &&
    910 		    cpuid_get_ncpu_per_chip(cpu) == 1)
    911 			break;
    912 #endif
    913 		/* disable TLB Flush Filter */
    914 
    915 		if ((error = checked_rdmsr(msr, &value)) != 0) {
    916 			msr_warning(cpu, "rd", msr, error);
    917 			workaround_warning(cpu, 122);
    918 			missing++;
    919 		} else {
    920 			value |= (uint64_t)AMD_HWCR_FFDIS;
    921 			if ((error = checked_wrmsr(msr, value)) != 0) {
    922 				msr_warning(cpu, "wr", msr, error);
    923 				workaround_warning(cpu, 122);
    924 				missing++;
    925 			}
    926 		}
    927 		opteron_erratum_122++;
    928 #else
    929 		workaround_warning(cpu, 122);
    930 		missing++;
    931 #endif
    932 	/*CONSTANTCONDITION*/
    933 	} while (0);
    934 
    935 	/*LINTED*/
    936 	if (cpuid_opteron_erratum(cpu, 123) > 0) do {
    937 		/*
    938 		 * Bypassed Reads May Cause Data Corruption of System Hang in
    939 		 * Dual Core Processors
    940 		 */
    941 #if defined(OPTERON_ERRATUM_123)
    942 		uint64_t value;
    943 		const uint_t msr = MSR_AMD_PATCHLEVEL;
    944 		int err;
    945 
    946 		/*
    947 		 * Erratum 123 applies only to multi-core cpus.
    948 		 */
    949 		if (cpuid_get_ncpu_per_chip(cpu) < 2)
    950 			break;
    951 #if defined(__xpv)
    952 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    953 			break;
    954 #endif
    955 		/*
    956 		 * The "workaround" is to print a warning to upgrade the BIOS
    957 		 */
    958 		if ((err = checked_rdmsr(msr, &value)) != 0) {
    959 			msr_warning(cpu, "rd", msr, err);
    960 			workaround_warning(cpu, 123);
    961 			missing++;
    962 		}
    963 		if (value == 0)
    964 			opteron_erratum_123++;
    965 #else
    966 		workaround_warning(cpu, 123);
    967 		missing++;
    968 
    969 #endif
    970 	/*CONSTANTCONDITION*/
    971 	} while (0);
    972 
    973 	/*LINTED*/
    974 	if (cpuid_opteron_erratum(cpu, 131) > 0) do {
    975 		/*
    976 		 * Multiprocessor Systems with Four or More Cores May Deadlock
    977 		 * Waiting for a Probe Response
    978 		 */
    979 #if defined(OPTERON_ERRATUM_131)
    980 		uint64_t nbcfg;
    981 		const uint_t msr = MSR_AMD_NB_CFG;
    982 		const uint64_t wabits =
    983 		    AMD_NB_CFG_SRQ_HEARTBEAT | AMD_NB_CFG_SRQ_SPR;
    984 		int error;
    985 
    986 		/*
    987 		 * Erratum 131 applies to any system with four or more cores.
    988 		 */
    989 		if (opteron_erratum_131)
    990 			break;
    991 #if defined(__xpv)
    992 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    993 			break;
    994 		if (xpv_nr_phys_cpus() < 4)
    995 			break;
    996 #else
    997 		if (opteron_get_nnodes() * cpuid_get_ncpu_per_chip(cpu) < 4)
    998 			break;
    999 #endif
   1000 		/*
   1001 		 * Print a warning if neither of the workarounds for
   1002 		 * erratum 131 is present.
   1003 		 */
   1004 		if ((error = checked_rdmsr(msr, &nbcfg)) != 0) {
   1005 			msr_warning(cpu, "rd", msr, error);
   1006 			workaround_warning(cpu, 131);
   1007 			missing++;
   1008 		} else if ((nbcfg & wabits) == 0) {
   1009 			opteron_erratum_131++;
   1010 		} else {
   1011 			/* cannot have both workarounds set */
   1012 			ASSERT((nbcfg & wabits) != wabits);
   1013 		}
   1014 #else
   1015 		workaround_warning(cpu, 131);
   1016 		missing++;
   1017 #endif
   1018 	/*CONSTANTCONDITION*/
   1019 	} while (0);
   1020 
   1021 	/*
   1022 	 * This isn't really an erratum, but for convenience the
   1023 	 * detection/workaround code lives here and in cpuid_opteron_erratum.
   1024 	 */
   1025 	if (cpuid_opteron_erratum(cpu, 6336786) > 0) {
   1026 #if defined(OPTERON_WORKAROUND_6336786)
   1027 		/*
   1028 		 * Disable C1-Clock ramping on multi-core/multi-processor
   1029 		 * K8 platforms to guard against TSC drift.
   1030 		 */
   1031 		if (opteron_workaround_6336786) {
   1032 			opteron_workaround_6336786++;
   1033 #if defined(__xpv)
   1034 		} else if ((DOMAIN_IS_INITDOMAIN(xen_info) &&
   1035 		    xpv_nr_phys_cpus() > 1) ||
   1036 		    opteron_workaround_6336786_UP) {
   1037 			/*
   1038 			 * XXPV	Hmm.  We can't walk the Northbridges on
   1039 			 *	the hypervisor; so just complain and drive
   1040 			 *	on.  This probably needs to be fixed in
   1041 			 *	the hypervisor itself.
   1042 			 */
   1043 			opteron_workaround_6336786++;
   1044 			workaround_warning(cpu, 6336786);
   1045 #else	/* __xpv */
   1046 		} else if ((opteron_get_nnodes() *
   1047 		    cpuid_get_ncpu_per_chip(cpu) > 1) ||
   1048 		    opteron_workaround_6336786_UP) {
   1049 
   1050 			uint_t	node, nnodes;
   1051 			uint8_t data;
   1052 
   1053 			nnodes = opteron_get_nnodes();
   1054 			for (node = 0; node < nnodes; node++) {
   1055 				/*
   1056 				 * Clear PMM7[1:0] (function 3, offset 0x87)
   1057 				 * Northbridge device is the node id + 24.
   1058 				 */
   1059 				data = pci_getb_func(0, node + 24, 3, 0x87);
   1060 				data &= 0xFC;
   1061 				pci_putb_func(0, node + 24, 3, 0x87, data);
   1062 			}
   1063 			opteron_workaround_6336786++;
   1064 #endif	/* __xpv */
   1065 		}
   1066 #else
   1067 		workaround_warning(cpu, 6336786);
   1068 		missing++;
   1069 #endif
   1070 	}
   1071 
   1072 	/*LINTED*/
   1073 	/*
   1074 	 * Mutex primitives don't work as expected.
   1075 	 */
   1076 	if (cpuid_opteron_erratum(cpu, 6323525) > 0) {
   1077 #if defined(OPTERON_WORKAROUND_6323525)
   1078 		/*
   1079 		 * This problem only occurs with 2 or more cores. If bit in
   1080 		 * MSR_AMD_BU_CFG set, then not applicable. The workaround
   1081 		 * is to patch the semaphone routines with the lfence
   1082 		 * instruction to provide necessary load memory barrier with
   1083 		 * possible subsequent read-modify-write ops.
   1084 		 *
   1085 		 * It is too early in boot to call the patch routine so
   1086 		 * set erratum variable to be done in startup_end().
   1087 		 */
   1088 		if (opteron_workaround_6323525) {
   1089 			opteron_workaround_6323525++;
   1090 #if defined(__xpv)
   1091 		} else if (x86_feature & X86_SSE2) {
   1092 			if (DOMAIN_IS_INITDOMAIN(xen_info)) {
   1093 				/*
   1094 				 * XXPV	Use dom0_msr here when extended
   1095 				 *	operations are supported?
   1096 				 */
   1097 				if (xpv_nr_phys_cpus() > 1)
   1098 					opteron_workaround_6323525++;
   1099 			} else {
   1100 				/*
   1101 				 * We have no way to tell how many physical
   1102 				 * cpus there are, or even if this processor
   1103 				 * has the problem, so enable the workaround
   1104 				 * unconditionally (at some performance cost).
   1105 				 */
   1106 				opteron_workaround_6323525++;
   1107 			}
   1108 #else	/* __xpv */
   1109 		} else if ((x86_feature & X86_SSE2) && ((opteron_get_nnodes() *
   1110 		    cpuid_get_ncpu_per_chip(cpu)) > 1)) {
   1111 			if ((xrdmsr(MSR_AMD_BU_CFG) & (UINT64_C(1) << 33)) == 0)
   1112 				opteron_workaround_6323525++;
   1113 #endif	/* __xpv */
   1114 		}
   1115 #else
   1116 		workaround_warning(cpu, 6323525);
   1117 		missing++;
   1118 #endif
   1119 	}
   1120 
   1121 	missing += do_erratum_298(cpu);
   1122 
   1123 #ifdef __xpv
   1124 	return (0);
   1125 #else
   1126 	return (missing);
   1127 #endif
   1128 }
   1129 
   1130 void
   1131 workaround_errata_end()
   1132 {
   1133 #if defined(OPTERON_ERRATUM_88)
   1134 	if (opteron_erratum_88)
   1135 		workaround_applied(88);
   1136 #endif
   1137 #if defined(OPTERON_ERRATUM_91)
   1138 	if (opteron_erratum_91)
   1139 		workaround_applied(91);
   1140 #endif
   1141 #if defined(OPTERON_ERRATUM_93)
   1142 	if (opteron_erratum_93)
   1143 		workaround_applied(93);
   1144 #endif
   1145 #if defined(OPTERON_ERRATUM_95)
   1146 	if (opteron_erratum_95)
   1147 		workaround_applied(95);
   1148 #endif
   1149 #if defined(OPTERON_ERRATUM_100)
   1150 	if (opteron_erratum_100)
   1151 		workaround_applied(100);
   1152 #endif
   1153 #if defined(OPTERON_ERRATUM_108)
   1154 	if (opteron_erratum_108)
   1155 		workaround_applied(108);
   1156 #endif
   1157 #if defined(OPTERON_ERRATUM_109)
   1158 	if (opteron_erratum_109) {
   1159 		cmn_err(CE_WARN,
   1160 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1161 		    " processor\nerratum 109 was not detected; updating your"
   1162 		    " system's BIOS to a version\ncontaining this"
   1163 		    " microcode patch is HIGHLY recommended or erroneous"
   1164 		    " system\noperation may occur.\n");
   1165 	}
   1166 #endif
   1167 #if defined(OPTERON_ERRATUM_121)
   1168 	if (opteron_erratum_121)
   1169 		workaround_applied(121);
   1170 #endif
   1171 #if defined(OPTERON_ERRATUM_122)
   1172 	if (opteron_erratum_122)
   1173 		workaround_applied(122);
   1174 #endif
   1175 #if defined(OPTERON_ERRATUM_123)
   1176 	if (opteron_erratum_123) {
   1177 		cmn_err(CE_WARN,
   1178 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1179 		    " processor\nerratum 123 was not detected; updating your"
   1180 		    " system's BIOS to a version\ncontaining this"
   1181 		    " microcode patch is HIGHLY recommended or erroneous"
   1182 		    " system\noperation may occur.\n");
   1183 	}
   1184 #endif
   1185 #if defined(OPTERON_ERRATUM_131)
   1186 	if (opteron_erratum_131) {
   1187 		cmn_err(CE_WARN,
   1188 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1189 		    " processor\nerratum 131 was not detected; updating your"
   1190 		    " system's BIOS to a version\ncontaining this"
   1191 		    " microcode patch is HIGHLY recommended or erroneous"
   1192 		    " system\noperation may occur.\n");
   1193 	}
   1194 #endif
   1195 #if defined(OPTERON_WORKAROUND_6336786)
   1196 	if (opteron_workaround_6336786)
   1197 		workaround_applied(6336786);
   1198 #endif
   1199 #if defined(OPTERON_WORKAROUND_6323525)
   1200 	if (opteron_workaround_6323525)
   1201 		workaround_applied(6323525);
   1202 #endif
   1203 #if defined(OPTERON_ERRATUM_298)
   1204 	if (opteron_erratum_298) {
   1205 		cmn_err(CE_WARN,
   1206 		    "BIOS microcode patch for AMD 64/Opteron(tm)"
   1207 		    " processor\nerratum 298 was not detected; updating your"
   1208 		    " system's BIOS to a version\ncontaining this"
   1209 		    " microcode patch is HIGHLY recommended or erroneous"
   1210 		    " system\noperation may occur.\n");
   1211 	}
   1212 #endif
   1213 }
   1214 
   1215 static cpuset_t procset;
   1216 
   1217 /*
   1218  * Start a single cpu, assuming that the kernel context is available
   1219  * to successfully start another cpu.
   1220  *
   1221  * (For example, real mode code is mapped into the right place
   1222  * in memory and is ready to be run.)
   1223  */
   1224 int
   1225 start_cpu(processorid_t who)
   1226 {
   1227 	void *ctx;
   1228 	cpu_t *cp;
   1229 	int delays;
   1230 	int error = 0;
   1231 
   1232 	ASSERT(who != 0);
   1233 
   1234 	/*
   1235 	 * Check if there's at least a Mbyte of kmem available
   1236 	 * before attempting to start the cpu.
   1237 	 */
   1238 	if (kmem_avail() < 1024 * 1024) {
   1239 		/*
   1240 		 * Kick off a reap in case that helps us with
   1241 		 * later attempts ..
   1242 		 */
   1243 		kmem_reap();
   1244 		return (ENOMEM);
   1245 	}
   1246 
   1247 	cp = mp_startup_init(who);
   1248 	if ((ctx = mach_cpucontext_alloc(cp)) == NULL ||
   1249 	    (error = mach_cpu_start(cp, ctx)) != 0) {
   1250 
   1251 		/*
   1252 		 * Something went wrong before we even started it
   1253 		 */
   1254 		if (ctx)
   1255 			cmn_err(CE_WARN,
   1256 			    "cpu%d: failed to start error %d",
   1257 			    cp->cpu_id, error);
   1258 		else
   1259 			cmn_err(CE_WARN,
   1260 			    "cpu%d: failed to allocate context", cp->cpu_id);
   1261 
   1262 		if (ctx)
   1263 			mach_cpucontext_free(cp, ctx, error);
   1264 		else
   1265 			error = EAGAIN;		/* hmm. */
   1266 		mp_startup_fini(cp, error);
   1267 		return (error);
   1268 	}
   1269 
   1270 	for (delays = 0; !CPU_IN_SET(procset, who); delays++) {
   1271 		if (delays == 500) {
   1272 			/*
   1273 			 * After five seconds, things are probably looking
   1274 			 * a bit bleak - explain the hang.
   1275 			 */
   1276 			cmn_err(CE_NOTE, "cpu%d: started, "
   1277 			    "but not running in the kernel yet", who);
   1278 		} else if (delays > 2000) {
   1279 			/*
   1280 			 * We waited at least 20 seconds, bail ..
   1281 			 */
   1282 			error = ETIMEDOUT;
   1283 			cmn_err(CE_WARN, "cpu%d: timed out", who);
   1284 			mach_cpucontext_free(cp, ctx, error);
   1285 			mp_startup_fini(cp, error);
   1286 			return (error);
   1287 		}
   1288 
   1289 		/*
   1290 		 * wait at least 10ms, then check again..
   1291 		 */
   1292 		delay(USEC_TO_TICK_ROUNDUP(10000));
   1293 	}
   1294 
   1295 	mach_cpucontext_free(cp, ctx, 0);
   1296 
   1297 #ifndef __xpv
   1298 	if (tsc_gethrtime_enable)
   1299 		tsc_sync_master(who);
   1300 #endif
   1301 
   1302 	if (dtrace_cpu_init != NULL) {
   1303 		/*
   1304 		 * DTrace CPU initialization expects cpu_lock to be held.
   1305 		 */
   1306 		mutex_enter(&cpu_lock);
   1307 		(*dtrace_cpu_init)(who);
   1308 		mutex_exit(&cpu_lock);
   1309 	}
   1310 
   1311 	while (!CPU_IN_SET(cpu_ready_set, who))
   1312 		delay(1);
   1313 
   1314 	return (0);
   1315 }
   1316 
   1317 
   1318 /*ARGSUSED*/
   1319 void
   1320 start_other_cpus(int cprboot)
   1321 {
   1322 	uint_t who;
   1323 	uint_t skipped = 0;
   1324 	uint_t bootcpuid = 0;
   1325 
   1326 	/*
   1327 	 * Initialize our own cpu_info.
   1328 	 */
   1329 	init_cpu_info(CPU);
   1330 
   1331 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_idstr);
   1332 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_brandstr);
   1333 
   1334 	/*
   1335 	 * Initialize our syscall handlers
   1336 	 */
   1337 	init_cpu_syscall(CPU);
   1338 
   1339 	/*
   1340 	 * Take the boot cpu out of the mp_cpus set because we know
   1341 	 * it's already running.  Add it to the cpu_ready_set for
   1342 	 * precisely the same reason.
   1343 	 */
   1344 	CPUSET_DEL(mp_cpus, bootcpuid);
   1345 	CPUSET_ADD(cpu_ready_set, bootcpuid);
   1346 
   1347 	/*
   1348 	 * if only 1 cpu or not using MP, skip the rest of this
   1349 	 */
   1350 	if (CPUSET_ISNULL(mp_cpus) || use_mp == 0) {
   1351 		if (use_mp == 0)
   1352 			cmn_err(CE_CONT, "?***** Not in MP mode\n");
   1353 		goto done;
   1354 	}
   1355 
   1356 	/*
   1357 	 * perform such initialization as is needed
   1358 	 * to be able to take CPUs on- and off-line.
   1359 	 */
   1360 	cpu_pause_init();
   1361 
   1362 	xc_init_cpu(CPU);		/* initialize processor crosscalls */
   1363 
   1364 	if (mach_cpucontext_init() != 0)
   1365 		goto done;
   1366 
   1367 	flushes_require_xcalls = 1;
   1368 
   1369 	/*
   1370 	 * We lock our affinity to the master CPU to ensure that all slave CPUs
   1371 	 * do their TSC syncs with the same CPU.
   1372 	 */
   1373 	affinity_set(CPU_CURRENT);
   1374 
   1375 	for (who = 0; who < NCPU; who++) {
   1376 
   1377 		if (!CPU_IN_SET(mp_cpus, who))
   1378 			continue;
   1379 		ASSERT(who != bootcpuid);
   1380 		if (ncpus >= max_ncpus) {
   1381 			skipped = who;
   1382 			continue;
   1383 		}
   1384 		if (start_cpu(who) != 0)
   1385 			CPUSET_DEL(mp_cpus, who);
   1386 
   1387 		mutex_enter(&cpu_lock);
   1388 		cpu_state_change_notify(who, CPU_SETUP);
   1389 		mutex_exit(&cpu_lock);
   1390 	}
   1391 
   1392 	/* Free the space allocated to hold the microcode file */
   1393 	ucode_cleanup();
   1394 
   1395 	affinity_clear();
   1396 
   1397 	if (skipped) {
   1398 		cmn_err(CE_NOTE,
   1399 		    "System detected %d cpus, but "
   1400 		    "only %d cpu(s) were enabled during boot.",
   1401 		    skipped + 1, ncpus);
   1402 		cmn_err(CE_NOTE,
   1403 		    "Use \"boot-ncpus\" parameter to enable more CPU(s). "
   1404 		    "See eeprom(1M).");
   1405 	}
   1406 
   1407 done:
   1408 	if (get_hwenv() == HW_NATIVE)
   1409 		workaround_errata_end();
   1410 	mach_cpucontext_fini();
   1411 
   1412 	cmi_post_mpstartup();
   1413 }
   1414 
   1415 /*
   1416  * Dummy functions - no i86pc platforms support dynamic cpu allocation.
   1417  */
   1418 /*ARGSUSED*/
   1419 int
   1420 mp_cpu_configure(int cpuid)
   1421 {
   1422 	return (ENOTSUP);		/* not supported */
   1423 }
   1424 
   1425 /*ARGSUSED*/
   1426 int
   1427 mp_cpu_unconfigure(int cpuid)
   1428 {
   1429 	return (ENOTSUP);		/* not supported */
   1430 }
   1431 
   1432 /*
   1433  * Startup function for 'other' CPUs (besides boot cpu).
   1434  * Called from real_mode_start.
   1435  *
   1436  * WARNING: until CPU_READY is set, mp_startup and routines called by
   1437  * mp_startup should not call routines (e.g. kmem_free) that could call
   1438  * hat_unload which requires CPU_READY to be set.
   1439  */
   1440 void
   1441 mp_startup(void)
   1442 {
   1443 	struct cpu *cp = CPU;
   1444 	uint_t new_x86_feature;
   1445 	extern void cpu_event_init_cpu(cpu_t *);
   1446 #ifndef __xpv
   1447 	extern void cpupm_init(cpu_t *);
   1448 #endif
   1449 	const char *fmt = "?cpu%d: %b\n";
   1450 
   1451 	/*
   1452 	 * We need to get TSC on this proc synced (i.e., any delta
   1453 	 * from cpu0 accounted for) as soon as we can, because many
   1454 	 * many things use gethrtime/pc_gethrestime, including
   1455 	 * interrupts, cmn_err, etc.
   1456 	 */
   1457 
   1458 	/* Let cpu0 continue into tsc_sync_master() */
   1459 	CPUSET_ATOMIC_ADD(procset, cp->cpu_id);
   1460 
   1461 #ifndef __xpv
   1462 	if (tsc_gethrtime_enable)
   1463 		tsc_sync_slave();
   1464 #endif
   1465 
   1466 	/*
   1467 	 * Once this was done from assembly, but it's safer here; if
   1468 	 * it blocks, we need to be able to swtch() to and from, and
   1469 	 * since we get here by calling t_pc, we need to do that call
   1470 	 * before swtch() overwrites it.
   1471 	 */
   1472 	(void) (*ap_mlsetup)();
   1473 
   1474 	new_x86_feature = cpuid_pass1(cp);
   1475 
   1476 #ifndef __xpv
   1477 	/*
   1478 	 * Program this cpu's PAT
   1479 	 */
   1480 	if (x86_feature & X86_PAT)
   1481 		pat_sync();
   1482 #endif
   1483 
   1484 	/*
   1485 	 * Set up TSC_AUX to contain the cpuid for this processor
   1486 	 * for the rdtscp instruction.
   1487 	 */
   1488 	if (x86_feature & X86_TSCP)
   1489 		(void) wrmsr(MSR_AMD_TSCAUX, cp->cpu_id);
   1490 
   1491 	/*
   1492 	 * Initialize this CPU's syscall handlers
   1493 	 */
   1494 	init_cpu_syscall(cp);
   1495 
   1496 	/*
   1497 	 * Enable interrupts with spl set to LOCK_LEVEL. LOCK_LEVEL is the
   1498 	 * highest level at which a routine is permitted to block on
   1499 	 * an adaptive mutex (allows for cpu poke interrupt in case
   1500 	 * the cpu is blocked on a mutex and halts). Setting LOCK_LEVEL blocks
   1501 	 * device interrupts that may end up in the hat layer issuing cross
   1502 	 * calls before CPU_READY is set.
   1503 	 */
   1504 	splx(ipltospl(LOCK_LEVEL));
   1505 	sti();
   1506 
   1507 	/*
   1508 	 * Do a sanity check to make sure this new CPU is a sane thing
   1509 	 * to add to the collection of processors running this system.
   1510 	 *
   1511 	 * XXX	Clearly this needs to get more sophisticated, if x86
   1512 	 * systems start to get built out of heterogenous CPUs; as is
   1513 	 * likely to happen once the number of processors in a configuration
   1514 	 * gets large enough.
   1515 	 */
   1516 	if ((x86_feature & new_x86_feature) != x86_feature) {
   1517 		cmn_err(CE_CONT, fmt, cp->cpu_id, new_x86_feature,
   1518 		    FMT_X86_FEATURE);
   1519 		cmn_err(CE_WARN, "cpu%d feature mismatch", cp->cpu_id);
   1520 	}
   1521 
   1522 	/*
   1523 	 * We do not support cpus with mixed monitor/mwait support if the
   1524 	 * boot cpu supports monitor/mwait.
   1525 	 */
   1526 	if ((x86_feature & ~new_x86_feature) & X86_MWAIT)
   1527 		panic("unsupported mixed cpu monitor/mwait support detected");
   1528 
   1529 	/*
   1530 	 * We could be more sophisticated here, and just mark the CPU
   1531 	 * as "faulted" but at this point we'll opt for the easier
   1532 	 * answer of dying horribly.  Provided the boot cpu is ok,
   1533 	 * the system can be recovered by booting with use_mp set to zero.
   1534 	 */
   1535 	if (workaround_errata(cp) != 0)
   1536 		panic("critical workaround(s) missing for cpu%d", cp->cpu_id);
   1537 
   1538 	cpuid_pass2(cp);
   1539 	cpuid_pass3(cp);
   1540 	(void) cpuid_pass4(cp);
   1541 
   1542 	init_cpu_info(cp);
   1543 
   1544 	mutex_enter(&cpu_lock);
   1545 
   1546 	cp->cpu_flags |= CPU_RUNNING | CPU_READY | CPU_EXISTS;
   1547 
   1548 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_idstr);
   1549 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_brandstr);
   1550 
   1551 	if (dtrace_cpu_init != NULL) {
   1552 		(*dtrace_cpu_init)(cp->cpu_id);
   1553 	}
   1554 
   1555 	/*
   1556 	 * Fill out cpu_ucode_info.  Update microcode if necessary.
   1557 	 */
   1558 	ucode_check(cp);
   1559 
   1560 	mutex_exit(&cpu_lock);
   1561 
   1562 	post_startup_cpu_fixups();
   1563 
   1564 	/*
   1565 	 * Enable preemption here so that contention for any locks acquired
   1566 	 * later in mp_startup may be preempted if the thread owning those
   1567 	 * locks is continuously executing on other CPUs (for example, this
   1568 	 * CPU must be preemptible to allow other CPUs to pause it during their
   1569 	 * startup phases).  It's safe to enable preemption here because the
   1570 	 * CPU state is pretty-much fully constructed.
   1571 	 */
   1572 	curthread->t_preempt = 0;
   1573 
   1574 	/* The base spl should still be at LOCK LEVEL here */
   1575 	ASSERT(cp->cpu_base_spl == ipltospl(LOCK_LEVEL));
   1576 	set_base_spl();		/* Restore the spl to its proper value */
   1577 
   1578 	cpu_event_init_cpu(cp);
   1579 #ifndef __xpv
   1580 	cpupm_init(cp);
   1581 #endif
   1582 
   1583 	/*
   1584 	 * Processor group initialization for this CPU is dependent on the
   1585 	 * cpuid probing, which must be done in the context of the current
   1586 	 * CPU, as well as the CPU's device node initialization (for ACPI).
   1587 	 */
   1588 	mutex_enter(&cpu_lock);
   1589 	pghw_physid_create(cp);
   1590 	pg_cpu_init(cp);
   1591 	pg_cmt_cpu_startup(cp);
   1592 	mutex_exit(&cpu_lock);
   1593 
   1594 	/* Enable interrupts */
   1595 	(void) spl0();
   1596 
   1597 	mutex_enter(&cpu_lock);
   1598 	cpu_enable_intr(cp);
   1599 	cpu_add_active(cp);
   1600 	mutex_exit(&cpu_lock);
   1601 
   1602 #ifndef __xpv
   1603 	{
   1604 		/*
   1605 		 * Set up the CPU module for this CPU.  This can't be done
   1606 		 * before this CPU is made CPU_READY, because we may (in
   1607 		 * heterogeneous systems) need to go load another CPU module.
   1608 		 * The act of attempting to load a module may trigger a
   1609 		 * cross-call, which will ASSERT unless this cpu is CPU_READY.
   1610 		 */
   1611 		cmi_hdl_t hdl;
   1612 
   1613 		if ((hdl = cmi_init(CMI_HDL_NATIVE, cmi_ntv_hwchipid(CPU),
   1614 		    cmi_ntv_hwcoreid(CPU), cmi_ntv_hwstrandid(CPU))) != NULL) {
   1615 			if (x86_feature & X86_MCA)
   1616 				cmi_mca_init(hdl);
   1617 		}
   1618 	}
   1619 #endif /* __xpv */
   1620 
   1621 	if (boothowto & RB_DEBUG)
   1622 		kdi_cpu_init();
   1623 
   1624 	/*
   1625 	 * Setting the bit in cpu_ready_set must be the last operation in
   1626 	 * processor initialization; the boot CPU will continue to boot once
   1627 	 * it sees this bit set for all active CPUs.
   1628 	 */
   1629 	CPUSET_ATOMIC_ADD(cpu_ready_set, cp->cpu_id);
   1630 
   1631 	/*
   1632 	 * Because mp_startup() gets fired off after init() starts, we
   1633 	 * can't use the '?' trick to do 'boot -v' printing - so we
   1634 	 * always direct the 'cpu .. online' messages to the log.
   1635 	 */
   1636 	cmn_err(CE_CONT, "!cpu%d initialization complete - online\n",
   1637 	    cp->cpu_id);
   1638 
   1639 	(void) mach_cpu_create_device_node(cp, NULL);
   1640 
   1641 	/*
   1642 	 * Now we are done with the startup thread, so free it up.
   1643 	 */
   1644 	thread_exit();
   1645 	panic("mp_startup: cannot return");
   1646 	/*NOTREACHED*/
   1647 }
   1648 
   1649 
   1650 /*
   1651  * Start CPU on user request.
   1652  */
   1653 /* ARGSUSED */
   1654 int
   1655 mp_cpu_start(struct cpu *cp)
   1656 {
   1657 	ASSERT(MUTEX_HELD(&cpu_lock));
   1658 	return (0);
   1659 }
   1660 
   1661 /*
   1662  * Stop CPU on user request.
   1663  */
   1664 /* ARGSUSED */
   1665 int
   1666 mp_cpu_stop(struct cpu *cp)
   1667 {
   1668 	extern int cbe_psm_timer_mode;
   1669 	ASSERT(MUTEX_HELD(&cpu_lock));
   1670 
   1671 #ifdef __xpv
   1672 	/*
   1673 	 * We can't offline vcpu0.
   1674 	 */
   1675 	if (cp->cpu_id == 0)
   1676 		return (EBUSY);
   1677 #endif
   1678 
   1679 	/*
   1680 	 * If TIMER_PERIODIC mode is used, CPU0 is the one running it;
   1681 	 * can't stop it.  (This is true only for machines with no TSC.)
   1682 	 */
   1683 
   1684 	if ((cbe_psm_timer_mode == TIMER_PERIODIC) && (cp->cpu_id == 0))
   1685 		return (EBUSY);
   1686 
   1687 	return (0);
   1688 }
   1689 
   1690 /*
   1691  * Take the specified CPU out of participation in interrupts.
   1692  */
   1693 int
   1694 cpu_disable_intr(struct cpu *cp)
   1695 {
   1696 	if (psm_disable_intr(cp->cpu_id) != DDI_SUCCESS)
   1697 		return (EBUSY);
   1698 
   1699 	cp->cpu_flags &= ~CPU_ENABLE;
   1700 	return (0);
   1701 }
   1702 
   1703 /*
   1704  * Allow the specified CPU to participate in interrupts.
   1705  */
   1706 void
   1707 cpu_enable_intr(struct cpu *cp)
   1708 {
   1709 	ASSERT(MUTEX_HELD(&cpu_lock));
   1710 	cp->cpu_flags |= CPU_ENABLE;
   1711 	psm_enable_intr(cp->cpu_id);
   1712 }
   1713 
   1714 
   1715 /*ARGSUSED*/
   1716 void
   1717 mp_cpu_faulted_enter(struct cpu *cp)
   1718 {
   1719 #ifndef __xpv
   1720 	cmi_hdl_t hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
   1721 	    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
   1722 
   1723 	if (hdl != NULL) {
   1724 		cmi_faulted_enter(hdl);
   1725 		cmi_hdl_rele(hdl);
   1726 	}
   1727 #endif
   1728 }
   1729 
   1730 /*ARGSUSED*/
   1731 void
   1732 mp_cpu_faulted_exit(struct cpu *cp)
   1733 {
   1734 #ifndef __xpv
   1735 	cmi_hdl_t hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
   1736 	    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
   1737 
   1738 	if (hdl != NULL) {
   1739 		cmi_faulted_exit(hdl);
   1740 		cmi_hdl_rele(hdl);
   1741 	}
   1742 #endif
   1743 }
   1744 
   1745 /*
   1746  * The following two routines are used as context operators on threads belonging
   1747  * to processes with a private LDT (see sysi86).  Due to the rarity of such
   1748  * processes, these routines are currently written for best code readability and
   1749  * organization rather than speed.  We could avoid checking x86_feature at every
   1750  * context switch by installing different context ops, depending on the
   1751  * x86_feature flags, at LDT creation time -- one for each combination of fast
   1752  * syscall feature flags.
   1753  */
   1754 
   1755 /*ARGSUSED*/
   1756 void
   1757 cpu_fast_syscall_disable(void *arg)
   1758 {
   1759 	if ((x86_feature & (X86_MSR | X86_SEP)) == (X86_MSR | X86_SEP))
   1760 		cpu_sep_disable();
   1761 	if ((x86_feature & (X86_MSR | X86_ASYSC)) == (X86_MSR | X86_ASYSC))
   1762 		cpu_asysc_disable();
   1763 }
   1764 
   1765 /*ARGSUSED*/
   1766 void
   1767 cpu_fast_syscall_enable(void *arg)
   1768 {
   1769 	if ((x86_feature & (X86_MSR | X86_SEP)) == (X86_MSR | X86_SEP))
   1770 		cpu_sep_enable();
   1771 	if ((x86_feature & (X86_MSR | X86_ASYSC)) == (X86_MSR | X86_ASYSC))
   1772 		cpu_asysc_enable();
   1773 }
   1774 
   1775 static void
   1776 cpu_sep_enable(void)
   1777 {
   1778 	ASSERT(x86_feature & X86_SEP);
   1779 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1780 
   1781 	wrmsr(MSR_INTC_SEP_CS, (uint64_t)(uintptr_t)KCS_SEL);
   1782 }
   1783 
   1784 static void
   1785 cpu_sep_disable(void)
   1786 {
   1787 	ASSERT(x86_feature & X86_SEP);
   1788 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1789 
   1790 	/*
   1791 	 * Setting the SYSENTER_CS_MSR register to 0 causes software executing
   1792 	 * the sysenter or sysexit instruction to trigger a #gp fault.
   1793 	 */
   1794 	wrmsr(MSR_INTC_SEP_CS, 0);
   1795 }
   1796 
   1797 static void
   1798 cpu_asysc_enable(void)
   1799 {
   1800 	ASSERT(x86_feature & X86_ASYSC);
   1801 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1802 
   1803 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) |
   1804 	    (uint64_t)(uintptr_t)AMD_EFER_SCE);
   1805 }
   1806 
   1807 static void
   1808 cpu_asysc_disable(void)
   1809 {
   1810 	ASSERT(x86_feature & X86_ASYSC);
   1811 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1812 
   1813 	/*
   1814 	 * Turn off the SCE (syscall enable) bit in the EFER register. Software
   1815 	 * executing syscall or sysret with this bit off will incur a #ud trap.
   1816 	 */
   1817 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) &
   1818 	    ~((uint64_t)(uintptr_t)AMD_EFER_SCE));
   1819 }
   1820