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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 	cp->cpu_m.mcpu_istamp = cpun << 16;
    262 
    263 	procp = curthread->t_procp;
    264 
    265 	mutex_enter(&cpu_lock);
    266 	/*
    267 	 * Initialize the dispatcher first.
    268 	 */
    269 	disp_cpu_init(cp);
    270 	mutex_exit(&cpu_lock);
    271 
    272 	cpu_vm_data_init(cp);
    273 
    274 	/*
    275 	 * Allocate and initialize the startup thread for this CPU.
    276 	 * Interrupt and process switch stacks get allocated later
    277 	 * when the CPU starts running.
    278 	 */
    279 	tp = thread_create(NULL, 0, NULL, NULL, 0, procp,
    280 	    TS_STOPPED, maxclsyspri);
    281 
    282 	/*
    283 	 * Set state to TS_ONPROC since this thread will start running
    284 	 * as soon as the CPU comes online.
    285 	 *
    286 	 * All the other fields of the thread structure are setup by
    287 	 * thread_create().
    288 	 */
    289 	THREAD_ONPROC(tp, cp);
    290 	tp->t_preempt = 1;
    291 	tp->t_bound_cpu = cp;
    292 	tp->t_affinitycnt = 1;
    293 	tp->t_cpu = cp;
    294 	tp->t_disp_queue = cp->cpu_disp;
    295 
    296 	/*
    297 	 * Setup thread to start in mp_startup.
    298 	 */
    299 	sp = tp->t_stk;
    300 	tp->t_pc = (uintptr_t)mp_startup;
    301 	tp->t_sp = (uintptr_t)(sp - MINFRAME);
    302 #if defined(__amd64)
    303 	tp->t_sp -= STACK_ENTRY_ALIGN;		/* fake a call */
    304 #endif
    305 
    306 	cp->cpu_id = cpun;
    307 	cp->cpu_self = cp;
    308 	cp->cpu_thread = tp;
    309 	cp->cpu_lwp = NULL;
    310 	cp->cpu_dispthread = tp;
    311 	cp->cpu_dispatch_pri = DISP_PRIO(tp);
    312 
    313 	/*
    314 	 * cpu_base_spl must be set explicitly here to prevent any blocking
    315 	 * operations in mp_startup from causing the spl of the cpu to drop
    316 	 * to 0 (allowing device interrupts before we're ready) in resume().
    317 	 * cpu_base_spl MUST remain at LOCK_LEVEL until the cpu is CPU_READY.
    318 	 * As an extra bit of security on DEBUG kernels, this is enforced with
    319 	 * an assertion in mp_startup() -- before cpu_base_spl is set to its
    320 	 * proper value.
    321 	 */
    322 	cp->cpu_base_spl = ipltospl(LOCK_LEVEL);
    323 
    324 	/*
    325 	 * Now, initialize per-CPU idle thread for this CPU.
    326 	 */
    327 	tp = thread_create(NULL, PAGESIZE, idle, NULL, 0, procp, TS_ONPROC, -1);
    328 
    329 	cp->cpu_idle_thread = tp;
    330 
    331 	tp->t_preempt = 1;
    332 	tp->t_bound_cpu = cp;
    333 	tp->t_affinitycnt = 1;
    334 	tp->t_cpu = cp;
    335 	tp->t_disp_queue = cp->cpu_disp;
    336 
    337 	/*
    338 	 * Bootstrap the CPU's PG data
    339 	 */
    340 	pg_cpu_bootstrap(cp);
    341 
    342 	/*
    343 	 * Perform CPC initialization on the new CPU.
    344 	 */
    345 	kcpc_hw_init(cp);
    346 
    347 	/*
    348 	 * Allocate virtual addresses for cpu_caddr1 and cpu_caddr2
    349 	 * for each CPU.
    350 	 */
    351 	setup_vaddr_for_ppcopy(cp);
    352 
    353 	/*
    354 	 * Allocate page for new GDT and initialize from current GDT.
    355 	 */
    356 #if !defined(__lint)
    357 	ASSERT((sizeof (*cp->cpu_gdt) * NGDT) <= PAGESIZE);
    358 #endif
    359 	cp->cpu_gdt = kmem_zalloc(PAGESIZE, KM_SLEEP);
    360 	bcopy(CPU->cpu_gdt, cp->cpu_gdt, (sizeof (*cp->cpu_gdt) * NGDT));
    361 
    362 #if defined(__i386)
    363 	/*
    364 	 * setup kernel %gs.
    365 	 */
    366 	set_usegd(&cp->cpu_gdt[GDT_GS], cp, sizeof (struct cpu) -1, SDT_MEMRWA,
    367 	    SEL_KPL, 0, 1);
    368 #endif
    369 
    370 	/*
    371 	 * If we have more than one node, each cpu gets a copy of IDT
    372 	 * local to its node. If this is a Pentium box, we use cpu 0's
    373 	 * IDT. cpu 0's IDT has been made read-only to workaround the
    374 	 * cmpxchgl register bug
    375 	 */
    376 	if (system_hardware.hd_nodes && x86_type != X86_TYPE_P5) {
    377 #if !defined(__lint)
    378 		ASSERT((sizeof (*CPU->cpu_idt) * NIDT) <= PAGESIZE);
    379 #endif
    380 		cp->cpu_idt = kmem_zalloc(PAGESIZE, KM_SLEEP);
    381 		bcopy(CPU->cpu_idt, cp->cpu_idt, PAGESIZE);
    382 	} else {
    383 		cp->cpu_idt = CPU->cpu_idt;
    384 	}
    385 
    386 	/*
    387 	 * Get interrupt priority data from cpu 0.
    388 	 */
    389 	cp->cpu_pri_data = CPU->cpu_pri_data;
    390 
    391 	/*
    392 	 * alloc space for cpuid info
    393 	 */
    394 	cpuid_alloc_space(cp);
    395 
    396 	/*
    397 	 * alloc space for ucode_info
    398 	 */
    399 	ucode_alloc_space(cp);
    400 	xc_init_cpu(cp);
    401 	hat_cpu_online(cp);
    402 
    403 #ifdef TRAPTRACE
    404 	/*
    405 	 * If this is a TRAPTRACE kernel, allocate TRAPTRACE buffers
    406 	 */
    407 	ttc->ttc_first = (uintptr_t)kmem_zalloc(trap_trace_bufsize, KM_SLEEP);
    408 	ttc->ttc_next = ttc->ttc_first;
    409 	ttc->ttc_limit = ttc->ttc_first + trap_trace_bufsize;
    410 #endif
    411 	/*
    412 	 * Record that we have another CPU.
    413 	 */
    414 	mutex_enter(&cpu_lock);
    415 	/*
    416 	 * Initialize the interrupt threads for this CPU
    417 	 */
    418 	cpu_intr_alloc(cp, NINTR_THREADS);
    419 	/*
    420 	 * Add CPU to list of available CPUs.  It'll be on the active list
    421 	 * after mp_startup().
    422 	 */
    423 	cpu_add_unit(cp);
    424 	mutex_exit(&cpu_lock);
    425 
    426 	return (cp);
    427 }
    428 
    429 /*
    430  * Undo what was done in mp_startup_init
    431  */
    432 static void
    433 mp_startup_fini(struct cpu *cp, int error)
    434 {
    435 	mutex_enter(&cpu_lock);
    436 
    437 	/*
    438 	 * Remove the CPU from the list of available CPUs.
    439 	 */
    440 	cpu_del_unit(cp->cpu_id);
    441 
    442 	if (error == ETIMEDOUT) {
    443 		/*
    444 		 * The cpu was started, but never *seemed* to run any
    445 		 * code in the kernel; it's probably off spinning in its
    446 		 * own private world, though with potential references to
    447 		 * our kmem-allocated IDTs and GDTs (for example).
    448 		 *
    449 		 * Worse still, it may actually wake up some time later,
    450 		 * so rather than guess what it might or might not do, we
    451 		 * leave the fundamental data structures intact.
    452 		 */
    453 		cp->cpu_flags = 0;
    454 		mutex_exit(&cpu_lock);
    455 		return;
    456 	}
    457 
    458 	/*
    459 	 * At this point, the only threads bound to this CPU should
    460 	 * special per-cpu threads: it's idle thread, it's pause threads,
    461 	 * and it's interrupt threads.  Clean these up.
    462 	 */
    463 	cpu_destroy_bound_threads(cp);
    464 	cp->cpu_idle_thread = NULL;
    465 
    466 	/*
    467 	 * Free the interrupt stack.
    468 	 */
    469 	segkp_release(segkp,
    470 	    cp->cpu_intr_stack - (INTR_STACK_SIZE - SA(MINFRAME)));
    471 
    472 	mutex_exit(&cpu_lock);
    473 
    474 #ifdef TRAPTRACE
    475 	/*
    476 	 * Discard the trap trace buffer
    477 	 */
    478 	{
    479 		trap_trace_ctl_t *ttc = &trap_trace_ctl[cp->cpu_id];
    480 
    481 		kmem_free((void *)ttc->ttc_first, trap_trace_bufsize);
    482 		ttc->ttc_first = NULL;
    483 	}
    484 #endif
    485 
    486 	hat_cpu_offline(cp);
    487 
    488 	cpuid_free_space(cp);
    489 
    490 	ucode_free_space(cp);
    491 
    492 	if (cp->cpu_idt != CPU->cpu_idt)
    493 		kmem_free(cp->cpu_idt, PAGESIZE);
    494 	cp->cpu_idt = NULL;
    495 
    496 	kmem_free(cp->cpu_gdt, PAGESIZE);
    497 	cp->cpu_gdt = NULL;
    498 
    499 	teardown_vaddr_for_ppcopy(cp);
    500 
    501 	kcpc_hw_fini(cp);
    502 
    503 	cp->cpu_dispthread = NULL;
    504 	cp->cpu_thread = NULL;	/* discarded by cpu_destroy_bound_threads() */
    505 
    506 	cpu_vm_data_destroy(cp);
    507 
    508 	mutex_enter(&cpu_lock);
    509 	disp_cpu_fini(cp);
    510 	mutex_exit(&cpu_lock);
    511 
    512 #if !defined(__xpv)
    513 	if (cp->cpu_m.mcpu_mwait != NULL)
    514 		cpuid_mwait_free(cp);
    515 #endif
    516 	kmem_free(cp, sizeof (*cp));
    517 }
    518 
    519 /*
    520  * Apply workarounds for known errata, and warn about those that are absent.
    521  *
    522  * System vendors occasionally create configurations which contain different
    523  * revisions of the CPUs that are almost but not exactly the same.  At the
    524  * time of writing, this meant that their clock rates were the same, their
    525  * feature sets were the same, but the required workaround were -not-
    526  * necessarily the same.  So, this routine is invoked on -every- CPU soon
    527  * after starting to make sure that the resulting system contains the most
    528  * pessimal set of workarounds needed to cope with *any* of the CPUs in the
    529  * system.
    530  *
    531  * workaround_errata is invoked early in mlsetup() for CPU 0, and in
    532  * mp_startup() for all slave CPUs. Slaves process workaround_errata prior
    533  * to acknowledging their readiness to the master, so this routine will
    534  * never be executed by multiple CPUs in parallel, thus making updates to
    535  * global data safe.
    536  *
    537  * These workarounds are based on Rev 3.57 of the Revision Guide for
    538  * AMD Athlon(tm) 64 and AMD Opteron(tm) Processors, August 2005.
    539  */
    540 
    541 #if defined(OPTERON_ERRATUM_88)
    542 int opteron_erratum_88;		/* if non-zero -> at least one cpu has it */
    543 #endif
    544 
    545 #if defined(OPTERON_ERRATUM_91)
    546 int opteron_erratum_91;		/* if non-zero -> at least one cpu has it */
    547 #endif
    548 
    549 #if defined(OPTERON_ERRATUM_93)
    550 int opteron_erratum_93;		/* if non-zero -> at least one cpu has it */
    551 #endif
    552 
    553 #if defined(OPTERON_ERRATUM_95)
    554 int opteron_erratum_95;		/* if non-zero -> at least one cpu has it */
    555 #endif
    556 
    557 #if defined(OPTERON_ERRATUM_100)
    558 int opteron_erratum_100;	/* if non-zero -> at least one cpu has it */
    559 #endif
    560 
    561 #if defined(OPTERON_ERRATUM_108)
    562 int opteron_erratum_108;	/* if non-zero -> at least one cpu has it */
    563 #endif
    564 
    565 #if defined(OPTERON_ERRATUM_109)
    566 int opteron_erratum_109;	/* if non-zero -> at least one cpu has it */
    567 #endif
    568 
    569 #if defined(OPTERON_ERRATUM_121)
    570 int opteron_erratum_121;	/* if non-zero -> at least one cpu has it */
    571 #endif
    572 
    573 #if defined(OPTERON_ERRATUM_122)
    574 int opteron_erratum_122;	/* if non-zero -> at least one cpu has it */
    575 #endif
    576 
    577 #if defined(OPTERON_ERRATUM_123)
    578 int opteron_erratum_123;	/* if non-zero -> at least one cpu has it */
    579 #endif
    580 
    581 #if defined(OPTERON_ERRATUM_131)
    582 int opteron_erratum_131;	/* if non-zero -> at least one cpu has it */
    583 #endif
    584 
    585 #if defined(OPTERON_WORKAROUND_6336786)
    586 int opteron_workaround_6336786;	/* non-zero -> WA relevant and applied */
    587 int opteron_workaround_6336786_UP = 0;	/* Not needed for UP */
    588 #endif
    589 
    590 #if defined(OPTERON_WORKAROUND_6323525)
    591 int opteron_workaround_6323525;	/* if non-zero -> at least one cpu has it */
    592 #endif
    593 
    594 #if defined(OPTERON_ERRATUM_298)
    595 int opteron_erratum_298;
    596 #endif
    597 
    598 static void
    599 workaround_warning(cpu_t *cp, uint_t erratum)
    600 {
    601 	cmn_err(CE_WARN, "cpu%d: no workaround for erratum %u",
    602 	    cp->cpu_id, erratum);
    603 }
    604 
    605 static void
    606 workaround_applied(uint_t erratum)
    607 {
    608 	if (erratum > 1000000)
    609 		cmn_err(CE_CONT, "?workaround applied for cpu issue #%d\n",
    610 		    erratum);
    611 	else
    612 		cmn_err(CE_CONT, "?workaround applied for cpu erratum #%d\n",
    613 		    erratum);
    614 }
    615 
    616 static void
    617 msr_warning(cpu_t *cp, const char *rw, uint_t msr, int error)
    618 {
    619 	cmn_err(CE_WARN, "cpu%d: couldn't %smsr 0x%x, error %d",
    620 	    cp->cpu_id, rw, msr, error);
    621 }
    622 
    623 /*
    624  * Determine the number of nodes in a Hammer / Greyhound / Griffin family
    625  * system.
    626  */
    627 static uint_t
    628 opteron_get_nnodes(void)
    629 {
    630 	static uint_t nnodes = 0;
    631 
    632 	if (nnodes == 0) {
    633 #ifdef	DEBUG
    634 		uint_t family;
    635 
    636 		/*
    637 		 * This routine uses a PCI config space based mechanism
    638 		 * for retrieving the number of nodes in the system.
    639 		 * Device 24, function 0, offset 0x60 as used here is not
    640 		 * AMD processor architectural, and may not work on processor
    641 		 * families other than those listed below.
    642 		 *
    643 		 * Callers of this routine must ensure that we're running on
    644 		 * a processor which supports this mechanism.
    645 		 * The assertion below is meant to catch calls on unsupported
    646 		 * processors.
    647 		 */
    648 		family = cpuid_getfamily(CPU);
    649 		ASSERT(family == 0xf || family == 0x10 || family == 0x11);
    650 #endif	/* DEBUG */
    651 
    652 		/*
    653 		 * Obtain the number of nodes in the system from
    654 		 * bits [6:4] of the Node ID register on node 0.
    655 		 *
    656 		 * The actual node count is NodeID[6:4] + 1
    657 		 *
    658 		 * The Node ID register is accessed via function 0,
    659 		 * offset 0x60. Node 0 is device 24.
    660 		 */
    661 		nnodes = ((pci_getl_func(0, 24, 0, 0x60) & 0x70) >> 4) + 1;
    662 	}
    663 	return (nnodes);
    664 }
    665 
    666 uint_t
    667 do_erratum_298(struct cpu *cpu)
    668 {
    669 	static int	osvwrc = -3;
    670 	extern int	osvw_opteron_erratum(cpu_t *, uint_t);
    671 
    672 	/*
    673 	 * L2 Eviction May Occur During Processor Operation To Set
    674 	 * Accessed or Dirty Bit.
    675 	 */
    676 	if (osvwrc == -3) {
    677 		osvwrc = osvw_opteron_erratum(cpu, 298);
    678 	} else {
    679 		/* osvw return codes should be consistent for all cpus */
    680 		ASSERT(osvwrc == osvw_opteron_erratum(cpu, 298));
    681 	}
    682 
    683 	switch (osvwrc) {
    684 	case 0:		/* erratum is not present: do nothing */
    685 		break;
    686 	case 1:		/* erratum is present: BIOS workaround applied */
    687 		/*
    688 		 * check if workaround is actually in place and issue warning
    689 		 * if not.
    690 		 */
    691 		if (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
    692 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0)) {
    693 #if defined(OPTERON_ERRATUM_298)
    694 			opteron_erratum_298++;
    695 #else
    696 			workaround_warning(cpu, 298);
    697 			return (1);
    698 #endif
    699 		}
    700 		break;
    701 	case -1:	/* cannot determine via osvw: check cpuid */
    702 		if ((cpuid_opteron_erratum(cpu, 298) > 0) &&
    703 		    (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
    704 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0))) {
    705 #if defined(OPTERON_ERRATUM_298)
    706 			opteron_erratum_298++;
    707 #else
    708 			workaround_warning(cpu, 298);
    709 			return (1);
    710 #endif
    711 		}
    712 		break;
    713 	}
    714 	return (0);
    715 }
    716 
    717 uint_t
    718 workaround_errata(struct cpu *cpu)
    719 {
    720 	uint_t missing = 0;
    721 
    722 	ASSERT(cpu == CPU);
    723 
    724 	/*LINTED*/
    725 	if (cpuid_opteron_erratum(cpu, 88) > 0) {
    726 		/*
    727 		 * SWAPGS May Fail To Read Correct GS Base
    728 		 */
    729 #if defined(OPTERON_ERRATUM_88)
    730 		/*
    731 		 * The workaround is an mfence in the relevant assembler code
    732 		 */
    733 		opteron_erratum_88++;
    734 #else
    735 		workaround_warning(cpu, 88);
    736 		missing++;
    737 #endif
    738 	}
    739 
    740 	if (cpuid_opteron_erratum(cpu, 91) > 0) {
    741 		/*
    742 		 * Software Prefetches May Report A Page Fault
    743 		 */
    744 #if defined(OPTERON_ERRATUM_91)
    745 		/*
    746 		 * fix is in trap.c
    747 		 */
    748 		opteron_erratum_91++;
    749 #else
    750 		workaround_warning(cpu, 91);
    751 		missing++;
    752 #endif
    753 	}
    754 
    755 	if (cpuid_opteron_erratum(cpu, 93) > 0) {
    756 		/*
    757 		 * RSM Auto-Halt Restart Returns to Incorrect RIP
    758 		 */
    759 #if defined(OPTERON_ERRATUM_93)
    760 		/*
    761 		 * fix is in trap.c
    762 		 */
    763 		opteron_erratum_93++;
    764 #else
    765 		workaround_warning(cpu, 93);
    766 		missing++;
    767 #endif
    768 	}
    769 
    770 	/*LINTED*/
    771 	if (cpuid_opteron_erratum(cpu, 95) > 0) {
    772 		/*
    773 		 * RET Instruction May Return to Incorrect EIP
    774 		 */
    775 #if defined(OPTERON_ERRATUM_95)
    776 #if defined(_LP64)
    777 		/*
    778 		 * Workaround this by ensuring that 32-bit user code and
    779 		 * 64-bit kernel code never occupy the same address
    780 		 * range mod 4G.
    781 		 */
    782 		if (_userlimit32 > 0xc0000000ul)
    783 			*(uintptr_t *)&_userlimit32 = 0xc0000000ul;
    784 
    785 		/*LINTED*/
    786 		ASSERT((uint32_t)COREHEAP_BASE == 0xc0000000u);
    787 		opteron_erratum_95++;
    788 #endif	/* _LP64 */
    789 #else
    790 		workaround_warning(cpu, 95);
    791 		missing++;
    792 #endif
    793 	}
    794 
    795 	if (cpuid_opteron_erratum(cpu, 100) > 0) {
    796 		/*
    797 		 * Compatibility Mode Branches Transfer to Illegal Address
    798 		 */
    799 #if defined(OPTERON_ERRATUM_100)
    800 		/*
    801 		 * fix is in trap.c
    802 		 */
    803 		opteron_erratum_100++;
    804 #else
    805 		workaround_warning(cpu, 100);
    806 		missing++;
    807 #endif
    808 	}
    809 
    810 	/*LINTED*/
    811 	if (cpuid_opteron_erratum(cpu, 108) > 0) {
    812 		/*
    813 		 * CPUID Instruction May Return Incorrect Model Number In
    814 		 * Some Processors
    815 		 */
    816 #if defined(OPTERON_ERRATUM_108)
    817 		/*
    818 		 * (Our cpuid-handling code corrects the model number on
    819 		 * those processors)
    820 		 */
    821 #else
    822 		workaround_warning(cpu, 108);
    823 		missing++;
    824 #endif
    825 	}
    826 
    827 	/*LINTED*/
    828 	if (cpuid_opteron_erratum(cpu, 109) > 0) do {
    829 		/*
    830 		 * Certain Reverse REP MOVS May Produce Unpredictable Behavior
    831 		 */
    832 #if defined(OPTERON_ERRATUM_109)
    833 		/*
    834 		 * The "workaround" is to print a warning to upgrade the BIOS
    835 		 */
    836 		uint64_t value;
    837 		const uint_t msr = MSR_AMD_PATCHLEVEL;
    838 		int err;
    839 
    840 		if ((err = checked_rdmsr(msr, &value)) != 0) {
    841 			msr_warning(cpu, "rd", msr, err);
    842 			workaround_warning(cpu, 109);
    843 			missing++;
    844 		}
    845 		if (value == 0)
    846 			opteron_erratum_109++;
    847 #else
    848 		workaround_warning(cpu, 109);
    849 		missing++;
    850 #endif
    851 	/*CONSTANTCONDITION*/
    852 	} while (0);
    853 
    854 	/*LINTED*/
    855 	if (cpuid_opteron_erratum(cpu, 121) > 0) {
    856 		/*
    857 		 * Sequential Execution Across Non_Canonical Boundary Caused
    858 		 * Processor Hang
    859 		 */
    860 #if defined(OPTERON_ERRATUM_121)
    861 #if defined(_LP64)
    862 		/*
    863 		 * Erratum 121 is only present in long (64 bit) mode.
    864 		 * Workaround is to include the page immediately before the
    865 		 * va hole to eliminate the possibility of system hangs due to
    866 		 * sequential execution across the va hole boundary.
    867 		 */
    868 		if (opteron_erratum_121)
    869 			opteron_erratum_121++;
    870 		else {
    871 			if (hole_start) {
    872 				hole_start -= PAGESIZE;
    873 			} else {
    874 				/*
    875 				 * hole_start not yet initialized by
    876 				 * mmu_init. Initialize hole_start
    877 				 * with value to be subtracted.
    878 				 */
    879 				hole_start = PAGESIZE;
    880 			}
    881 			opteron_erratum_121++;
    882 		}
    883 #endif	/* _LP64 */
    884 #else
    885 		workaround_warning(cpu, 121);
    886 		missing++;
    887 #endif
    888 	}
    889 
    890 	/*LINTED*/
    891 	if (cpuid_opteron_erratum(cpu, 122) > 0) do {
    892 		/*
    893 		 * TLB Flush Filter May Cause Coherency Problem in
    894 		 * Multiprocessor Systems
    895 		 */
    896 #if defined(OPTERON_ERRATUM_122)
    897 		uint64_t value;
    898 		const uint_t msr = MSR_AMD_HWCR;
    899 		int error;
    900 
    901 		/*
    902 		 * Erratum 122 is only present in MP configurations (multi-core
    903 		 * or multi-processor).
    904 		 */
    905 #if defined(__xpv)
    906 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    907 			break;
    908 		if (!opteron_erratum_122 && xpv_nr_phys_cpus() == 1)
    909 			break;
    910 #else
    911 		if (!opteron_erratum_122 && opteron_get_nnodes() == 1 &&
    912 		    cpuid_get_ncpu_per_chip(cpu) == 1)
    913 			break;
    914 #endif
    915 		/* disable TLB Flush Filter */
    916 
    917 		if ((error = checked_rdmsr(msr, &value)) != 0) {
    918 			msr_warning(cpu, "rd", msr, error);
    919 			workaround_warning(cpu, 122);
    920 			missing++;
    921 		} else {
    922 			value |= (uint64_t)AMD_HWCR_FFDIS;
    923 			if ((error = checked_wrmsr(msr, value)) != 0) {
    924 				msr_warning(cpu, "wr", msr, error);
    925 				workaround_warning(cpu, 122);
    926 				missing++;
    927 			}
    928 		}
    929 		opteron_erratum_122++;
    930 #else
    931 		workaround_warning(cpu, 122);
    932 		missing++;
    933 #endif
    934 	/*CONSTANTCONDITION*/
    935 	} while (0);
    936 
    937 	/*LINTED*/
    938 	if (cpuid_opteron_erratum(cpu, 123) > 0) do {
    939 		/*
    940 		 * Bypassed Reads May Cause Data Corruption of System Hang in
    941 		 * Dual Core Processors
    942 		 */
    943 #if defined(OPTERON_ERRATUM_123)
    944 		uint64_t value;
    945 		const uint_t msr = MSR_AMD_PATCHLEVEL;
    946 		int err;
    947 
    948 		/*
    949 		 * Erratum 123 applies only to multi-core cpus.
    950 		 */
    951 		if (cpuid_get_ncpu_per_chip(cpu) < 2)
    952 			break;
    953 #if defined(__xpv)
    954 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    955 			break;
    956 #endif
    957 		/*
    958 		 * The "workaround" is to print a warning to upgrade the BIOS
    959 		 */
    960 		if ((err = checked_rdmsr(msr, &value)) != 0) {
    961 			msr_warning(cpu, "rd", msr, err);
    962 			workaround_warning(cpu, 123);
    963 			missing++;
    964 		}
    965 		if (value == 0)
    966 			opteron_erratum_123++;
    967 #else
    968 		workaround_warning(cpu, 123);
    969 		missing++;
    970 
    971 #endif
    972 	/*CONSTANTCONDITION*/
    973 	} while (0);
    974 
    975 	/*LINTED*/
    976 	if (cpuid_opteron_erratum(cpu, 131) > 0) do {
    977 		/*
    978 		 * Multiprocessor Systems with Four or More Cores May Deadlock
    979 		 * Waiting for a Probe Response
    980 		 */
    981 #if defined(OPTERON_ERRATUM_131)
    982 		uint64_t nbcfg;
    983 		const uint_t msr = MSR_AMD_NB_CFG;
    984 		const uint64_t wabits =
    985 		    AMD_NB_CFG_SRQ_HEARTBEAT | AMD_NB_CFG_SRQ_SPR;
    986 		int error;
    987 
    988 		/*
    989 		 * Erratum 131 applies to any system with four or more cores.
    990 		 */
    991 		if (opteron_erratum_131)
    992 			break;
    993 #if defined(__xpv)
    994 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
    995 			break;
    996 		if (xpv_nr_phys_cpus() < 4)
    997 			break;
    998 #else
    999 		if (opteron_get_nnodes() * cpuid_get_ncpu_per_chip(cpu) < 4)
   1000 			break;
   1001 #endif
   1002 		/*
   1003 		 * Print a warning if neither of the workarounds for
   1004 		 * erratum 131 is present.
   1005 		 */
   1006 		if ((error = checked_rdmsr(msr, &nbcfg)) != 0) {
   1007 			msr_warning(cpu, "rd", msr, error);
   1008 			workaround_warning(cpu, 131);
   1009 			missing++;
   1010 		} else if ((nbcfg & wabits) == 0) {
   1011 			opteron_erratum_131++;
   1012 		} else {
   1013 			/* cannot have both workarounds set */
   1014 			ASSERT((nbcfg & wabits) != wabits);
   1015 		}
   1016 #else
   1017 		workaround_warning(cpu, 131);
   1018 		missing++;
   1019 #endif
   1020 	/*CONSTANTCONDITION*/
   1021 	} while (0);
   1022 
   1023 	/*
   1024 	 * This isn't really an erratum, but for convenience the
   1025 	 * detection/workaround code lives here and in cpuid_opteron_erratum.
   1026 	 */
   1027 	if (cpuid_opteron_erratum(cpu, 6336786) > 0) {
   1028 #if defined(OPTERON_WORKAROUND_6336786)
   1029 		/*
   1030 		 * Disable C1-Clock ramping on multi-core/multi-processor
   1031 		 * K8 platforms to guard against TSC drift.
   1032 		 */
   1033 		if (opteron_workaround_6336786) {
   1034 			opteron_workaround_6336786++;
   1035 #if defined(__xpv)
   1036 		} else if ((DOMAIN_IS_INITDOMAIN(xen_info) &&
   1037 		    xpv_nr_phys_cpus() > 1) ||
   1038 		    opteron_workaround_6336786_UP) {
   1039 			/*
   1040 			 * XXPV	Hmm.  We can't walk the Northbridges on
   1041 			 *	the hypervisor; so just complain and drive
   1042 			 *	on.  This probably needs to be fixed in
   1043 			 *	the hypervisor itself.
   1044 			 */
   1045 			opteron_workaround_6336786++;
   1046 			workaround_warning(cpu, 6336786);
   1047 #else	/* __xpv */
   1048 		} else if ((opteron_get_nnodes() *
   1049 		    cpuid_get_ncpu_per_chip(cpu) > 1) ||
   1050 		    opteron_workaround_6336786_UP) {
   1051 
   1052 			uint_t	node, nnodes;
   1053 			uint8_t data;
   1054 
   1055 			nnodes = opteron_get_nnodes();
   1056 			for (node = 0; node < nnodes; node++) {
   1057 				/*
   1058 				 * Clear PMM7[1:0] (function 3, offset 0x87)
   1059 				 * Northbridge device is the node id + 24.
   1060 				 */
   1061 				data = pci_getb_func(0, node + 24, 3, 0x87);
   1062 				data &= 0xFC;
   1063 				pci_putb_func(0, node + 24, 3, 0x87, data);
   1064 			}
   1065 			opteron_workaround_6336786++;
   1066 #endif	/* __xpv */
   1067 		}
   1068 #else
   1069 		workaround_warning(cpu, 6336786);
   1070 		missing++;
   1071 #endif
   1072 	}
   1073 
   1074 	/*LINTED*/
   1075 	/*
   1076 	 * Mutex primitives don't work as expected.
   1077 	 */
   1078 	if (cpuid_opteron_erratum(cpu, 6323525) > 0) {
   1079 #if defined(OPTERON_WORKAROUND_6323525)
   1080 		/*
   1081 		 * This problem only occurs with 2 or more cores. If bit in
   1082 		 * MSR_AMD_BU_CFG set, then not applicable. The workaround
   1083 		 * is to patch the semaphone routines with the lfence
   1084 		 * instruction to provide necessary load memory barrier with
   1085 		 * possible subsequent read-modify-write ops.
   1086 		 *
   1087 		 * It is too early in boot to call the patch routine so
   1088 		 * set erratum variable to be done in startup_end().
   1089 		 */
   1090 		if (opteron_workaround_6323525) {
   1091 			opteron_workaround_6323525++;
   1092 #if defined(__xpv)
   1093 		} else if (x86_feature & X86_SSE2) {
   1094 			if (DOMAIN_IS_INITDOMAIN(xen_info)) {
   1095 				/*
   1096 				 * XXPV	Use dom0_msr here when extended
   1097 				 *	operations are supported?
   1098 				 */
   1099 				if (xpv_nr_phys_cpus() > 1)
   1100 					opteron_workaround_6323525++;
   1101 			} else {
   1102 				/*
   1103 				 * We have no way to tell how many physical
   1104 				 * cpus there are, or even if this processor
   1105 				 * has the problem, so enable the workaround
   1106 				 * unconditionally (at some performance cost).
   1107 				 */
   1108 				opteron_workaround_6323525++;
   1109 			}
   1110 #else	/* __xpv */
   1111 		} else if ((x86_feature & X86_SSE2) && ((opteron_get_nnodes() *
   1112 		    cpuid_get_ncpu_per_chip(cpu)) > 1)) {
   1113 			if ((xrdmsr(MSR_AMD_BU_CFG) & (UINT64_C(1) << 33)) == 0)
   1114 				opteron_workaround_6323525++;
   1115 #endif	/* __xpv */
   1116 		}
   1117 #else
   1118 		workaround_warning(cpu, 6323525);
   1119 		missing++;
   1120 #endif
   1121 	}
   1122 
   1123 	missing += do_erratum_298(cpu);
   1124 
   1125 #ifdef __xpv
   1126 	return (0);
   1127 #else
   1128 	return (missing);
   1129 #endif
   1130 }
   1131 
   1132 void
   1133 workaround_errata_end()
   1134 {
   1135 #if defined(OPTERON_ERRATUM_88)
   1136 	if (opteron_erratum_88)
   1137 		workaround_applied(88);
   1138 #endif
   1139 #if defined(OPTERON_ERRATUM_91)
   1140 	if (opteron_erratum_91)
   1141 		workaround_applied(91);
   1142 #endif
   1143 #if defined(OPTERON_ERRATUM_93)
   1144 	if (opteron_erratum_93)
   1145 		workaround_applied(93);
   1146 #endif
   1147 #if defined(OPTERON_ERRATUM_95)
   1148 	if (opteron_erratum_95)
   1149 		workaround_applied(95);
   1150 #endif
   1151 #if defined(OPTERON_ERRATUM_100)
   1152 	if (opteron_erratum_100)
   1153 		workaround_applied(100);
   1154 #endif
   1155 #if defined(OPTERON_ERRATUM_108)
   1156 	if (opteron_erratum_108)
   1157 		workaround_applied(108);
   1158 #endif
   1159 #if defined(OPTERON_ERRATUM_109)
   1160 	if (opteron_erratum_109) {
   1161 		cmn_err(CE_WARN,
   1162 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1163 		    " processor\nerratum 109 was not detected; updating your"
   1164 		    " system's BIOS to a version\ncontaining this"
   1165 		    " microcode patch is HIGHLY recommended or erroneous"
   1166 		    " system\noperation may occur.\n");
   1167 	}
   1168 #endif
   1169 #if defined(OPTERON_ERRATUM_121)
   1170 	if (opteron_erratum_121)
   1171 		workaround_applied(121);
   1172 #endif
   1173 #if defined(OPTERON_ERRATUM_122)
   1174 	if (opteron_erratum_122)
   1175 		workaround_applied(122);
   1176 #endif
   1177 #if defined(OPTERON_ERRATUM_123)
   1178 	if (opteron_erratum_123) {
   1179 		cmn_err(CE_WARN,
   1180 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1181 		    " processor\nerratum 123 was not detected; updating your"
   1182 		    " system's BIOS to a version\ncontaining this"
   1183 		    " microcode patch is HIGHLY recommended or erroneous"
   1184 		    " system\noperation may occur.\n");
   1185 	}
   1186 #endif
   1187 #if defined(OPTERON_ERRATUM_131)
   1188 	if (opteron_erratum_131) {
   1189 		cmn_err(CE_WARN,
   1190 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
   1191 		    " processor\nerratum 131 was not detected; updating your"
   1192 		    " system's BIOS to a version\ncontaining this"
   1193 		    " microcode patch is HIGHLY recommended or erroneous"
   1194 		    " system\noperation may occur.\n");
   1195 	}
   1196 #endif
   1197 #if defined(OPTERON_WORKAROUND_6336786)
   1198 	if (opteron_workaround_6336786)
   1199 		workaround_applied(6336786);
   1200 #endif
   1201 #if defined(OPTERON_WORKAROUND_6323525)
   1202 	if (opteron_workaround_6323525)
   1203 		workaround_applied(6323525);
   1204 #endif
   1205 #if defined(OPTERON_ERRATUM_298)
   1206 	if (opteron_erratum_298) {
   1207 		cmn_err(CE_WARN,
   1208 		    "BIOS microcode patch for AMD 64/Opteron(tm)"
   1209 		    " processor\nerratum 298 was not detected; updating your"
   1210 		    " system's BIOS to a version\ncontaining this"
   1211 		    " microcode patch is HIGHLY recommended or erroneous"
   1212 		    " system\noperation may occur.\n");
   1213 	}
   1214 #endif
   1215 }
   1216 
   1217 static cpuset_t procset;
   1218 
   1219 /*
   1220  * Start a single cpu, assuming that the kernel context is available
   1221  * to successfully start another cpu.
   1222  *
   1223  * (For example, real mode code is mapped into the right place
   1224  * in memory and is ready to be run.)
   1225  */
   1226 int
   1227 start_cpu(processorid_t who)
   1228 {
   1229 	void *ctx;
   1230 	cpu_t *cp;
   1231 	int delays;
   1232 	int error = 0;
   1233 
   1234 	ASSERT(who != 0);
   1235 
   1236 	/*
   1237 	 * Check if there's at least a Mbyte of kmem available
   1238 	 * before attempting to start the cpu.
   1239 	 */
   1240 	if (kmem_avail() < 1024 * 1024) {
   1241 		/*
   1242 		 * Kick off a reap in case that helps us with
   1243 		 * later attempts ..
   1244 		 */
   1245 		kmem_reap();
   1246 		return (ENOMEM);
   1247 	}
   1248 
   1249 	cp = mp_startup_init(who);
   1250 	if ((ctx = mach_cpucontext_alloc(cp)) == NULL ||
   1251 	    (error = mach_cpu_start(cp, ctx)) != 0) {
   1252 
   1253 		/*
   1254 		 * Something went wrong before we even started it
   1255 		 */
   1256 		if (ctx)
   1257 			cmn_err(CE_WARN,
   1258 			    "cpu%d: failed to start error %d",
   1259 			    cp->cpu_id, error);
   1260 		else
   1261 			cmn_err(CE_WARN,
   1262 			    "cpu%d: failed to allocate context", cp->cpu_id);
   1263 
   1264 		if (ctx)
   1265 			mach_cpucontext_free(cp, ctx, error);
   1266 		else
   1267 			error = EAGAIN;		/* hmm. */
   1268 		mp_startup_fini(cp, error);
   1269 		return (error);
   1270 	}
   1271 
   1272 	for (delays = 0; !CPU_IN_SET(procset, who); delays++) {
   1273 		if (delays == 500) {
   1274 			/*
   1275 			 * After five seconds, things are probably looking
   1276 			 * a bit bleak - explain the hang.
   1277 			 */
   1278 			cmn_err(CE_NOTE, "cpu%d: started, "
   1279 			    "but not running in the kernel yet", who);
   1280 		} else if (delays > 2000) {
   1281 			/*
   1282 			 * We waited at least 20 seconds, bail ..
   1283 			 */
   1284 			error = ETIMEDOUT;
   1285 			cmn_err(CE_WARN, "cpu%d: timed out", who);
   1286 			mach_cpucontext_free(cp, ctx, error);
   1287 			mp_startup_fini(cp, error);
   1288 			return (error);
   1289 		}
   1290 
   1291 		/*
   1292 		 * wait at least 10ms, then check again..
   1293 		 */
   1294 		delay(USEC_TO_TICK_ROUNDUP(10000));
   1295 	}
   1296 
   1297 	mach_cpucontext_free(cp, ctx, 0);
   1298 
   1299 #ifndef __xpv
   1300 	if (tsc_gethrtime_enable)
   1301 		tsc_sync_master(who);
   1302 #endif
   1303 
   1304 	if (dtrace_cpu_init != NULL) {
   1305 		/*
   1306 		 * DTrace CPU initialization expects cpu_lock to be held.
   1307 		 */
   1308 		mutex_enter(&cpu_lock);
   1309 		(*dtrace_cpu_init)(who);
   1310 		mutex_exit(&cpu_lock);
   1311 	}
   1312 
   1313 	while (!CPU_IN_SET(cpu_ready_set, who))
   1314 		delay(1);
   1315 
   1316 	return (0);
   1317 }
   1318 
   1319 
   1320 /*ARGSUSED*/
   1321 void
   1322 start_other_cpus(int cprboot)
   1323 {
   1324 	uint_t who;
   1325 	uint_t skipped = 0;
   1326 	uint_t bootcpuid = 0;
   1327 
   1328 	/*
   1329 	 * Initialize our own cpu_info.
   1330 	 */
   1331 	init_cpu_info(CPU);
   1332 
   1333 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_idstr);
   1334 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_brandstr);
   1335 
   1336 	/*
   1337 	 * Initialize our syscall handlers
   1338 	 */
   1339 	init_cpu_syscall(CPU);
   1340 
   1341 	/*
   1342 	 * Take the boot cpu out of the mp_cpus set because we know
   1343 	 * it's already running.  Add it to the cpu_ready_set for
   1344 	 * precisely the same reason.
   1345 	 */
   1346 	CPUSET_DEL(mp_cpus, bootcpuid);
   1347 	CPUSET_ADD(cpu_ready_set, bootcpuid);
   1348 
   1349 	/*
   1350 	 * if only 1 cpu or not using MP, skip the rest of this
   1351 	 */
   1352 	if (CPUSET_ISNULL(mp_cpus) || use_mp == 0) {
   1353 		if (use_mp == 0)
   1354 			cmn_err(CE_CONT, "?***** Not in MP mode\n");
   1355 		goto done;
   1356 	}
   1357 
   1358 	/*
   1359 	 * perform such initialization as is needed
   1360 	 * to be able to take CPUs on- and off-line.
   1361 	 */
   1362 	cpu_pause_init();
   1363 
   1364 	xc_init_cpu(CPU);		/* initialize processor crosscalls */
   1365 
   1366 	if (mach_cpucontext_init() != 0)
   1367 		goto done;
   1368 
   1369 	flushes_require_xcalls = 1;
   1370 
   1371 	/*
   1372 	 * We lock our affinity to the master CPU to ensure that all slave CPUs
   1373 	 * do their TSC syncs with the same CPU.
   1374 	 */
   1375 	affinity_set(CPU_CURRENT);
   1376 
   1377 	for (who = 0; who < NCPU; who++) {
   1378 
   1379 		if (!CPU_IN_SET(mp_cpus, who))
   1380 			continue;
   1381 		ASSERT(who != bootcpuid);
   1382 		if (ncpus >= max_ncpus) {
   1383 			skipped = who;
   1384 			continue;
   1385 		}
   1386 		if (start_cpu(who) != 0)
   1387 			CPUSET_DEL(mp_cpus, who);
   1388 
   1389 		mutex_enter(&cpu_lock);
   1390 		cpu_state_change_notify(who, CPU_SETUP);
   1391 		mutex_exit(&cpu_lock);
   1392 	}
   1393 
   1394 	/* Free the space allocated to hold the microcode file */
   1395 	ucode_cleanup();
   1396 
   1397 	affinity_clear();
   1398 
   1399 	if (skipped) {
   1400 		cmn_err(CE_NOTE,
   1401 		    "System detected %d cpus, but "
   1402 		    "only %d cpu(s) were enabled during boot.",
   1403 		    skipped + 1, ncpus);
   1404 		cmn_err(CE_NOTE,
   1405 		    "Use \"boot-ncpus\" parameter to enable more CPU(s). "
   1406 		    "See eeprom(1M).");
   1407 	}
   1408 
   1409 done:
   1410 	if (get_hwenv() == HW_NATIVE)
   1411 		workaround_errata_end();
   1412 	mach_cpucontext_fini();
   1413 
   1414 	cmi_post_mpstartup();
   1415 }
   1416 
   1417 /*
   1418  * Dummy functions - no i86pc platforms support dynamic cpu allocation.
   1419  */
   1420 /*ARGSUSED*/
   1421 int
   1422 mp_cpu_configure(int cpuid)
   1423 {
   1424 	return (ENOTSUP);		/* not supported */
   1425 }
   1426 
   1427 /*ARGSUSED*/
   1428 int
   1429 mp_cpu_unconfigure(int cpuid)
   1430 {
   1431 	return (ENOTSUP);		/* not supported */
   1432 }
   1433 
   1434 /*
   1435  * Startup function for 'other' CPUs (besides boot cpu).
   1436  * Called from real_mode_start.
   1437  *
   1438  * WARNING: until CPU_READY is set, mp_startup and routines called by
   1439  * mp_startup should not call routines (e.g. kmem_free) that could call
   1440  * hat_unload which requires CPU_READY to be set.
   1441  */
   1442 void
   1443 mp_startup(void)
   1444 {
   1445 	struct cpu *cp = CPU;
   1446 	uint_t new_x86_feature;
   1447 	extern void cpu_event_init_cpu(cpu_t *);
   1448 #ifndef __xpv
   1449 	extern void cpupm_init(cpu_t *);
   1450 #endif
   1451 	const char *fmt = "?cpu%d: %b\n";
   1452 
   1453 	/*
   1454 	 * We need to get TSC on this proc synced (i.e., any delta
   1455 	 * from cpu0 accounted for) as soon as we can, because many
   1456 	 * many things use gethrtime/pc_gethrestime, including
   1457 	 * interrupts, cmn_err, etc.
   1458 	 */
   1459 
   1460 	/* Let cpu0 continue into tsc_sync_master() */
   1461 	CPUSET_ATOMIC_ADD(procset, cp->cpu_id);
   1462 
   1463 #ifndef __xpv
   1464 	if (tsc_gethrtime_enable)
   1465 		tsc_sync_slave();
   1466 #endif
   1467 
   1468 	/*
   1469 	 * Once this was done from assembly, but it's safer here; if
   1470 	 * it blocks, we need to be able to swtch() to and from, and
   1471 	 * since we get here by calling t_pc, we need to do that call
   1472 	 * before swtch() overwrites it.
   1473 	 */
   1474 	(void) (*ap_mlsetup)();
   1475 
   1476 	new_x86_feature = cpuid_pass1(cp);
   1477 
   1478 #ifndef __xpv
   1479 	/*
   1480 	 * Program this cpu's PAT
   1481 	 */
   1482 	if (x86_feature & X86_PAT)
   1483 		pat_sync();
   1484 #endif
   1485 
   1486 	/*
   1487 	 * Set up TSC_AUX to contain the cpuid for this processor
   1488 	 * for the rdtscp instruction.
   1489 	 */
   1490 	if (x86_feature & X86_TSCP)
   1491 		(void) wrmsr(MSR_AMD_TSCAUX, cp->cpu_id);
   1492 
   1493 	/*
   1494 	 * Initialize this CPU's syscall handlers
   1495 	 */
   1496 	init_cpu_syscall(cp);
   1497 
   1498 	/*
   1499 	 * Enable interrupts with spl set to LOCK_LEVEL. LOCK_LEVEL is the
   1500 	 * highest level at which a routine is permitted to block on
   1501 	 * an adaptive mutex (allows for cpu poke interrupt in case
   1502 	 * the cpu is blocked on a mutex and halts). Setting LOCK_LEVEL blocks
   1503 	 * device interrupts that may end up in the hat layer issuing cross
   1504 	 * calls before CPU_READY is set.
   1505 	 */
   1506 	splx(ipltospl(LOCK_LEVEL));
   1507 	sti();
   1508 
   1509 	/*
   1510 	 * Do a sanity check to make sure this new CPU is a sane thing
   1511 	 * to add to the collection of processors running this system.
   1512 	 *
   1513 	 * XXX	Clearly this needs to get more sophisticated, if x86
   1514 	 * systems start to get built out of heterogenous CPUs; as is
   1515 	 * likely to happen once the number of processors in a configuration
   1516 	 * gets large enough.
   1517 	 */
   1518 	if ((x86_feature & new_x86_feature) != x86_feature) {
   1519 		cmn_err(CE_CONT, fmt, cp->cpu_id, new_x86_feature,
   1520 		    FMT_X86_FEATURE);
   1521 		cmn_err(CE_WARN, "cpu%d feature mismatch", cp->cpu_id);
   1522 	}
   1523 
   1524 	/*
   1525 	 * We do not support cpus with mixed monitor/mwait support if the
   1526 	 * boot cpu supports monitor/mwait.
   1527 	 */
   1528 	if ((x86_feature & ~new_x86_feature) & X86_MWAIT)
   1529 		panic("unsupported mixed cpu monitor/mwait support detected");
   1530 
   1531 	/*
   1532 	 * We could be more sophisticated here, and just mark the CPU
   1533 	 * as "faulted" but at this point we'll opt for the easier
   1534 	 * answer of dying horribly.  Provided the boot cpu is ok,
   1535 	 * the system can be recovered by booting with use_mp set to zero.
   1536 	 */
   1537 	if (workaround_errata(cp) != 0)
   1538 		panic("critical workaround(s) missing for cpu%d", cp->cpu_id);
   1539 
   1540 	cpuid_pass2(cp);
   1541 	cpuid_pass3(cp);
   1542 	(void) cpuid_pass4(cp);
   1543 
   1544 	init_cpu_info(cp);
   1545 
   1546 	mutex_enter(&cpu_lock);
   1547 
   1548 	cp->cpu_flags |= CPU_RUNNING | CPU_READY | CPU_EXISTS;
   1549 
   1550 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_idstr);
   1551 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_brandstr);
   1552 
   1553 	if (dtrace_cpu_init != NULL) {
   1554 		(*dtrace_cpu_init)(cp->cpu_id);
   1555 	}
   1556 
   1557 	/*
   1558 	 * Fill out cpu_ucode_info.  Update microcode if necessary.
   1559 	 */
   1560 	ucode_check(cp);
   1561 
   1562 	mutex_exit(&cpu_lock);
   1563 
   1564 	post_startup_cpu_fixups();
   1565 
   1566 	/*
   1567 	 * Enable preemption here so that contention for any locks acquired
   1568 	 * later in mp_startup may be preempted if the thread owning those
   1569 	 * locks is continuously executing on other CPUs (for example, this
   1570 	 * CPU must be preemptible to allow other CPUs to pause it during their
   1571 	 * startup phases).  It's safe to enable preemption here because the
   1572 	 * CPU state is pretty-much fully constructed.
   1573 	 */
   1574 	curthread->t_preempt = 0;
   1575 
   1576 	/* The base spl should still be at LOCK LEVEL here */
   1577 	ASSERT(cp->cpu_base_spl == ipltospl(LOCK_LEVEL));
   1578 	set_base_spl();		/* Restore the spl to its proper value */
   1579 
   1580 	cpu_event_init_cpu(cp);
   1581 #ifndef __xpv
   1582 	cpupm_init(cp);
   1583 #endif
   1584 
   1585 	/*
   1586 	 * Processor group initialization for this CPU is dependent on the
   1587 	 * cpuid probing, which must be done in the context of the current
   1588 	 * CPU, as well as the CPU's device node initialization (for ACPI).
   1589 	 */
   1590 	mutex_enter(&cpu_lock);
   1591 	pghw_physid_create(cp);
   1592 	(void) pg_cpu_init(cp, B_FALSE);
   1593 	pg_cmt_cpu_startup(cp);
   1594 	mutex_exit(&cpu_lock);
   1595 
   1596 	/* Enable interrupts */
   1597 	(void) spl0();
   1598 
   1599 	mutex_enter(&cpu_lock);
   1600 	cpu_enable_intr(cp);
   1601 	cpu_add_active(cp);
   1602 	mutex_exit(&cpu_lock);
   1603 
   1604 #ifndef __xpv
   1605 	{
   1606 		/*
   1607 		 * Set up the CPU module for this CPU.  This can't be done
   1608 		 * before this CPU is made CPU_READY, because we may (in
   1609 		 * heterogeneous systems) need to go load another CPU module.
   1610 		 * The act of attempting to load a module may trigger a
   1611 		 * cross-call, which will ASSERT unless this cpu is CPU_READY.
   1612 		 */
   1613 		cmi_hdl_t hdl;
   1614 
   1615 		if ((hdl = cmi_init(CMI_HDL_NATIVE, cmi_ntv_hwchipid(CPU),
   1616 		    cmi_ntv_hwcoreid(CPU), cmi_ntv_hwstrandid(CPU))) != NULL) {
   1617 			if (x86_feature & X86_MCA)
   1618 				cmi_mca_init(hdl);
   1619 		}
   1620 	}
   1621 #endif /* __xpv */
   1622 
   1623 	if (boothowto & RB_DEBUG)
   1624 		kdi_cpu_init();
   1625 
   1626 	/*
   1627 	 * Setting the bit in cpu_ready_set must be the last operation in
   1628 	 * processor initialization; the boot CPU will continue to boot once
   1629 	 * it sees this bit set for all active CPUs.
   1630 	 */
   1631 	CPUSET_ATOMIC_ADD(cpu_ready_set, cp->cpu_id);
   1632 
   1633 	/*
   1634 	 * Because mp_startup() gets fired off after init() starts, we
   1635 	 * can't use the '?' trick to do 'boot -v' printing - so we
   1636 	 * always direct the 'cpu .. online' messages to the log.
   1637 	 */
   1638 	cmn_err(CE_CONT, "!cpu%d initialization complete - online\n",
   1639 	    cp->cpu_id);
   1640 
   1641 	(void) mach_cpu_create_device_node(cp, NULL);
   1642 
   1643 	/*
   1644 	 * Now we are done with the startup thread, so free it up.
   1645 	 */
   1646 	thread_exit();
   1647 	panic("mp_startup: cannot return");
   1648 	/*NOTREACHED*/
   1649 }
   1650 
   1651 
   1652 /*
   1653  * Start CPU on user request.
   1654  */
   1655 /* ARGSUSED */
   1656 int
   1657 mp_cpu_start(struct cpu *cp)
   1658 {
   1659 	ASSERT(MUTEX_HELD(&cpu_lock));
   1660 	return (0);
   1661 }
   1662 
   1663 /*
   1664  * Stop CPU on user request.
   1665  */
   1666 /* ARGSUSED */
   1667 int
   1668 mp_cpu_stop(struct cpu *cp)
   1669 {
   1670 	extern int cbe_psm_timer_mode;
   1671 	ASSERT(MUTEX_HELD(&cpu_lock));
   1672 
   1673 #ifdef __xpv
   1674 	/*
   1675 	 * We can't offline vcpu0.
   1676 	 */
   1677 	if (cp->cpu_id == 0)
   1678 		return (EBUSY);
   1679 #endif
   1680 
   1681 	/*
   1682 	 * If TIMER_PERIODIC mode is used, CPU0 is the one running it;
   1683 	 * can't stop it.  (This is true only for machines with no TSC.)
   1684 	 */
   1685 
   1686 	if ((cbe_psm_timer_mode == TIMER_PERIODIC) && (cp->cpu_id == 0))
   1687 		return (EBUSY);
   1688 
   1689 	return (0);
   1690 }
   1691 
   1692 /*
   1693  * Take the specified CPU out of participation in interrupts.
   1694  */
   1695 int
   1696 cpu_disable_intr(struct cpu *cp)
   1697 {
   1698 	if (psm_disable_intr(cp->cpu_id) != DDI_SUCCESS)
   1699 		return (EBUSY);
   1700 
   1701 	cp->cpu_flags &= ~CPU_ENABLE;
   1702 	return (0);
   1703 }
   1704 
   1705 /*
   1706  * Allow the specified CPU to participate in interrupts.
   1707  */
   1708 void
   1709 cpu_enable_intr(struct cpu *cp)
   1710 {
   1711 	ASSERT(MUTEX_HELD(&cpu_lock));
   1712 	cp->cpu_flags |= CPU_ENABLE;
   1713 	psm_enable_intr(cp->cpu_id);
   1714 }
   1715 
   1716 
   1717 /*ARGSUSED*/
   1718 void
   1719 mp_cpu_faulted_enter(struct cpu *cp)
   1720 {
   1721 #ifndef __xpv
   1722 	cmi_hdl_t hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
   1723 	    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
   1724 
   1725 	if (hdl != NULL) {
   1726 		cmi_faulted_enter(hdl);
   1727 		cmi_hdl_rele(hdl);
   1728 	}
   1729 #endif
   1730 }
   1731 
   1732 /*ARGSUSED*/
   1733 void
   1734 mp_cpu_faulted_exit(struct cpu *cp)
   1735 {
   1736 #ifndef __xpv
   1737 	cmi_hdl_t hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
   1738 	    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
   1739 
   1740 	if (hdl != NULL) {
   1741 		cmi_faulted_exit(hdl);
   1742 		cmi_hdl_rele(hdl);
   1743 	}
   1744 #endif
   1745 }
   1746 
   1747 /*
   1748  * The following two routines are used as context operators on threads belonging
   1749  * to processes with a private LDT (see sysi86).  Due to the rarity of such
   1750  * processes, these routines are currently written for best code readability and
   1751  * organization rather than speed.  We could avoid checking x86_feature at every
   1752  * context switch by installing different context ops, depending on the
   1753  * x86_feature flags, at LDT creation time -- one for each combination of fast
   1754  * syscall feature flags.
   1755  */
   1756 
   1757 /*ARGSUSED*/
   1758 void
   1759 cpu_fast_syscall_disable(void *arg)
   1760 {
   1761 	if ((x86_feature & (X86_MSR | X86_SEP)) == (X86_MSR | X86_SEP))
   1762 		cpu_sep_disable();
   1763 	if ((x86_feature & (X86_MSR | X86_ASYSC)) == (X86_MSR | X86_ASYSC))
   1764 		cpu_asysc_disable();
   1765 }
   1766 
   1767 /*ARGSUSED*/
   1768 void
   1769 cpu_fast_syscall_enable(void *arg)
   1770 {
   1771 	if ((x86_feature & (X86_MSR | X86_SEP)) == (X86_MSR | X86_SEP))
   1772 		cpu_sep_enable();
   1773 	if ((x86_feature & (X86_MSR | X86_ASYSC)) == (X86_MSR | X86_ASYSC))
   1774 		cpu_asysc_enable();
   1775 }
   1776 
   1777 static void
   1778 cpu_sep_enable(void)
   1779 {
   1780 	ASSERT(x86_feature & X86_SEP);
   1781 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1782 
   1783 	wrmsr(MSR_INTC_SEP_CS, (uint64_t)(uintptr_t)KCS_SEL);
   1784 }
   1785 
   1786 static void
   1787 cpu_sep_disable(void)
   1788 {
   1789 	ASSERT(x86_feature & X86_SEP);
   1790 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1791 
   1792 	/*
   1793 	 * Setting the SYSENTER_CS_MSR register to 0 causes software executing
   1794 	 * the sysenter or sysexit instruction to trigger a #gp fault.
   1795 	 */
   1796 	wrmsr(MSR_INTC_SEP_CS, 0);
   1797 }
   1798 
   1799 static void
   1800 cpu_asysc_enable(void)
   1801 {
   1802 	ASSERT(x86_feature & X86_ASYSC);
   1803 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1804 
   1805 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) |
   1806 	    (uint64_t)(uintptr_t)AMD_EFER_SCE);
   1807 }
   1808 
   1809 static void
   1810 cpu_asysc_disable(void)
   1811 {
   1812 	ASSERT(x86_feature & X86_ASYSC);
   1813 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
   1814 
   1815 	/*
   1816 	 * Turn off the SCE (syscall enable) bit in the EFER register. Software
   1817 	 * executing syscall or sysret with this bit off will incur a #ud trap.
   1818 	 */
   1819 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) &
   1820 	    ~((uint64_t)(uintptr_t)AMD_EFER_SCE));
   1821 }
   1822