xref: /titanic_41/usr/src/uts/i86pc/os/mp_pc.c (revision fc0105de770cee6a3fd91de949b9927fba6e894b)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * Welcome to the world of the "real mode platter".
28  * See also startup.c, mpcore.s and apic.c for related routines.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/systm.h>
33 #include <sys/cpuvar.h>
34 #include <sys/kmem.h>
35 #include <sys/archsystm.h>
36 #include <sys/machsystm.h>
37 #include <sys/controlregs.h>
38 #include <sys/x86_archext.h>
39 #include <sys/smp_impldefs.h>
40 #include <sys/sysmacros.h>
41 #include <sys/mach_mmu.h>
42 #include <sys/promif.h>
43 #include <sys/cpu.h>
44 #include <vm/hat_i86.h>
45 
46 extern void real_mode_start(void);
47 extern void real_mode_end(void);
48 extern void *(*cpu_pause_func)(void *);
49 
50 void rmp_gdt_init(rm_platter_t *);
51 
52 /*
53  * Fill up the real mode platter to make it easy for real mode code to
54  * kick it off. This area should really be one passed by boot to kernel
55  * and guaranteed to be below 1MB and aligned to 16 bytes. Should also
56  * have identical physical and virtual address in paged mode.
57  */
58 static ushort_t *warm_reset_vector = NULL;
59 
60 int
61 mach_cpucontext_init(void)
62 {
63 	ushort_t *vec;
64 
65 	if (!(vec = (ushort_t *)psm_map_phys(WARM_RESET_VECTOR,
66 	    sizeof (vec), PROT_READ | PROT_WRITE)))
67 		return (-1);
68 	/*
69 	 * setup secondary cpu bios boot up vector
70 	 */
71 	*vec = (ushort_t)((caddr_t)
72 	    ((struct rm_platter *)rm_platter_va)->rm_code - rm_platter_va
73 	    + ((ulong_t)rm_platter_va & 0xf));
74 	vec[1] = (ushort_t)(rm_platter_pa >> 4);
75 	warm_reset_vector = vec;
76 
77 	bcopy((caddr_t)real_mode_start,
78 	    (caddr_t)((rm_platter_t *)rm_platter_va)->rm_code,
79 	    (size_t)real_mode_end - (size_t)real_mode_start);
80 
81 	return (0);
82 }
83 
84 void
85 mach_cpucontext_fini(void)
86 {
87 	if (warm_reset_vector)
88 		psm_unmap_phys((caddr_t)warm_reset_vector,
89 		    sizeof (warm_reset_vector));
90 	hat_unload(kas.a_hat, (caddr_t)(uintptr_t)rm_platter_pa, MMU_PAGESIZE,
91 	    HAT_UNLOAD);
92 }
93 
94 #if defined(__amd64)
95 extern void *long_mode_64(void);
96 #endif	/* __amd64 */
97 
98 void *
99 mach_cpucontext_alloc(struct cpu *cp)
100 {
101 	rm_platter_t *rm = (rm_platter_t *)rm_platter_va;
102 	struct cpu_tables *ct;
103 	struct tss *ntss;
104 
105 	/*
106 	 * Allocate space for stack, tss, gdt and idt. We round the size
107 	 * allotted for cpu_tables up, so that the TSS is on a unique page.
108 	 * This is more efficient when running in virtual machines.
109 	 */
110 	ct = kmem_zalloc(P2ROUNDUP(sizeof (*ct), PAGESIZE), KM_SLEEP);
111 	if ((uintptr_t)ct & PAGEOFFSET)
112 		panic("mp_startup_init: cpu%d misaligned tables", cp->cpu_id);
113 
114 	ntss = cp->cpu_tss = &ct->ct_tss;
115 
116 #if defined(__amd64)
117 
118 	/*
119 	 * #DF (double fault).
120 	 */
121 	ntss->tss_ist1 = (uint64_t)&ct->ct_stack[sizeof (ct->ct_stack)];
122 
123 #elif defined(__i386)
124 
125 	ntss->tss_esp0 = ntss->tss_esp1 = ntss->tss_esp2 = ntss->tss_esp =
126 	    (uint32_t)&ct->ct_stack[sizeof (ct->ct_stack)];
127 
128 	ntss->tss_ss0 = ntss->tss_ss1 = ntss->tss_ss2 = ntss->tss_ss = KDS_SEL;
129 
130 	ntss->tss_eip = (uint32_t)cp->cpu_thread->t_pc;
131 
132 	ntss->tss_cs = KCS_SEL;
133 	ntss->tss_ds = ntss->tss_es = KDS_SEL;
134 	ntss->tss_fs = KFS_SEL;
135 	ntss->tss_gs = KGS_SEL;
136 
137 #endif	/* __i386 */
138 
139 	/*
140 	 * Set I/O bit map offset equal to size of TSS segment limit
141 	 * for no I/O permission map. This will cause all user I/O
142 	 * instructions to generate #gp fault.
143 	 */
144 	ntss->tss_bitmapbase = sizeof (*ntss);
145 
146 	/*
147 	 * Setup kernel tss.
148 	 */
149 	set_syssegd((system_desc_t *)&cp->cpu_gdt[GDT_KTSS], cp->cpu_tss,
150 	    sizeof (*cp->cpu_tss) - 1, SDT_SYSTSS, SEL_KPL);
151 
152 	/*
153 	 * Now copy all that we've set up onto the real mode platter
154 	 * for the real mode code to digest as part of starting the cpu.
155 	 */
156 
157 	rm->rm_idt_base = cp->cpu_idt;
158 	rm->rm_idt_lim = sizeof (*cp->cpu_idt) * NIDT - 1;
159 	rm->rm_gdt_base = cp->cpu_gdt;
160 	rm->rm_gdt_lim = sizeof (*cp->cpu_gdt) * NGDT - 1;
161 
162 	rm->rm_pdbr = getcr3();
163 	rm->rm_cpu = cp->cpu_id;
164 	rm->rm_x86feature = x86_feature;
165 	rm->rm_cr4 = getcr4();
166 
167 	rmp_gdt_init(rm);
168 
169 	return (ct);
170 }
171 
172 /*ARGSUSED*/
173 void
174 rmp_gdt_init(rm_platter_t *rm)
175 {
176 
177 #if defined(__amd64)
178 
179 	if (getcr3() > 0xffffffffUL)
180 		panic("Cannot initialize CPUs; kernel's 64-bit page tables\n"
181 		    "located above 4G in physical memory (@ 0x%lx)", getcr3());
182 
183 	/*
184 	 * Setup pseudo-descriptors for temporary GDT and IDT for use ONLY
185 	 * by code in real_mode_start():
186 	 *
187 	 * GDT[0]:  NULL selector
188 	 * GDT[1]:  64-bit CS: Long = 1, Present = 1, bits 12, 11 = 1
189 	 *
190 	 * Clear the IDT as interrupts will be off and a limit of 0 will cause
191 	 * the CPU to triple fault and reset on an NMI, seemingly as reasonable
192 	 * a course of action as any other, though it may cause the entire
193 	 * platform to reset in some cases...
194 	 */
195 	rm->rm_temp_gdt[0] = 0;
196 	rm->rm_temp_gdt[TEMPGDT_KCODE64] = 0x20980000000000ULL;
197 
198 	rm->rm_temp_gdt_lim = (ushort_t)(sizeof (rm->rm_temp_gdt) - 1);
199 	rm->rm_temp_gdt_base = rm_platter_pa +
200 	    (uint32_t)offsetof(rm_platter_t, rm_temp_gdt);
201 	rm->rm_temp_idt_lim = 0;
202 	rm->rm_temp_idt_base = 0;
203 
204 	/*
205 	 * Since the CPU needs to jump to protected mode using an identity
206 	 * mapped address, we need to calculate it here.
207 	 */
208 	rm->rm_longmode64_addr = rm_platter_pa +
209 	    ((uint32_t)long_mode_64 - (uint32_t)real_mode_start);
210 #endif	/* __amd64 */
211 }
212 
213 /*ARGSUSED*/
214 void
215 mach_cpucontext_free(struct cpu *cp, void *arg, int err)
216 {
217 	struct cpu_tables *ct = arg;
218 
219 	ASSERT(&ct->ct_tss == cp->cpu_tss);
220 
221 	switch (err) {
222 	case 0:
223 		break;
224 	case ETIMEDOUT:
225 		/*
226 		 * The processor was poked, but failed to start before
227 		 * we gave up waiting for it.  In case it starts later,
228 		 * don't free anything.
229 		 */
230 		break;
231 	default:
232 		/*
233 		 * Some other, passive, error occurred.
234 		 */
235 		kmem_free(ct, P2ROUNDUP(sizeof (*ct), PAGESIZE));
236 		cp->cpu_tss = NULL;
237 		break;
238 	}
239 }
240 
241 /*
242  * "Enter monitor."  Called via cross-call from stop_other_cpus().
243  */
244 void
245 mach_cpu_halt(char *msg)
246 {
247 	if (msg)
248 		prom_printf("%s\n", msg);
249 
250 	/*CONSTANTCONDITION*/
251 	while (1)
252 		;
253 }
254 
255 void
256 mach_cpu_idle(void)
257 {
258 	i86_halt();
259 }
260 
261 void
262 mach_cpu_pause(volatile char *safe)
263 {
264 	/*
265 	 * This cpu is now safe.
266 	 */
267 	*safe = PAUSE_WAIT;
268 	membar_enter(); /* make sure stores are flushed */
269 
270 	/*
271 	 * Now we wait.  When we are allowed to continue, safe
272 	 * will be set to PAUSE_IDLE.
273 	 */
274 	while (*safe != PAUSE_IDLE)
275 		SMT_PAUSE();
276 }
277 
278 /*
279  * Power on CPU.
280  */
281 /*ARGSUSED*/
282 int
283 mp_cpu_poweron(struct cpu *cp)
284 {
285 	ASSERT(MUTEX_HELD(&cpu_lock));
286 	return (ENOTSUP);		/* not supported */
287 }
288 
289 /*
290  * Power off CPU.
291  */
292 /*ARGSUSED*/
293 int
294 mp_cpu_poweroff(struct cpu *cp)
295 {
296 	ASSERT(MUTEX_HELD(&cpu_lock));
297 	return (ENOTSUP);		/* not supported */
298 }
299 
300 /*
301  * Return vcpu state, since this could be a virtual environment that we
302  * are unaware of, return "unknown".
303  */
304 /* ARGSUSED */
305 int
306 vcpu_on_pcpu(processorid_t cpu)
307 {
308 	return (VCPU_STATE_UNKNOWN);
309 }
310