xref: /titanic_52/usr/src/uts/intel/os/arch_kdi.c (revision 500b1e787b108592a37e3d54dc9b5e676de5386d)
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  * Kernel/Debugger Interface (KDI) routines.  Called during debugger under
28  * various system states (boot, while running, while the debugger has control).
29  * Functions intended for use while the debugger has control may not grab any
30  * locks or perform any functions that assume the availability of other system
31  * services.
32  */
33 
34 #include <sys/systm.h>
35 #include <sys/x86_archext.h>
36 #include <sys/kdi_impl.h>
37 #include <sys/smp_impldefs.h>
38 #include <sys/psm_types.h>
39 #include <sys/segments.h>
40 #include <sys/archsystm.h>
41 #include <sys/controlregs.h>
42 #include <sys/trap.h>
43 #include <sys/kobj.h>
44 #include <sys/kobj_impl.h>
45 #include <sys/clock_impl.h>
46 
47 static void
48 kdi_system_claim(void)
49 {
50 	lbolt_debug_entry();
51 
52 	psm_notifyf(PSM_DEBUG_ENTER);
53 }
54 
55 static void
56 kdi_system_release(void)
57 {
58 	psm_notifyf(PSM_DEBUG_EXIT);
59 
60 	lbolt_debug_return();
61 }
62 
63 static cpu_t *
64 kdi_gdt2cpu(uintptr_t gdtbase)
65 {
66 	cpu_t *cp = cpu_list;
67 
68 	if (cp == NULL)
69 		return (NULL);
70 
71 	do {
72 		if (gdtbase == (uintptr_t)cp->cpu_gdt)
73 			return (cp);
74 	} while ((cp = cp->cpu_next) != cpu_list);
75 
76 	return (NULL);
77 }
78 
79 #if defined(__amd64)
80 uintptr_t
81 kdi_gdt2gsbase(uintptr_t gdtbase)
82 {
83 	return ((uintptr_t)kdi_gdt2cpu(gdtbase));
84 }
85 #endif
86 
87 static uintptr_t
88 kdi_get_userlimit(void)
89 {
90 	return (_userlimit);
91 }
92 
93 static int
94 kdi_get_cpuinfo(uint_t *vendorp, uint_t *familyp, uint_t *modelp)
95 {
96 	desctbr_t gdtr;
97 	cpu_t *cpu;
98 
99 	/*
100 	 * CPU doesn't work until the GDT and gs/GSBASE have been set up.
101 	 * Boot-loaded kmdb will call us well before then, so we have to
102 	 * find the current cpu_t the hard way.
103 	 */
104 	rd_gdtr(&gdtr);
105 	if ((cpu = kdi_gdt2cpu(gdtr.dtr_base)) == NULL ||
106 	    !cpuid_checkpass(cpu, 1))
107 		return (EAGAIN); /* cpuid isn't done yet */
108 
109 	*vendorp = cpuid_getvendor(cpu);
110 	*familyp = cpuid_getfamily(cpu);
111 	*modelp = cpuid_getmodel(cpu);
112 
113 	return (0);
114 }
115 
116 void
117 kdi_idtr_set(gate_desc_t *idt, size_t limit)
118 {
119 	desctbr_t idtr;
120 
121 	/*
122 	 * This rare case could happen if we entered kmdb whilst still on the
123 	 * fake CPU set up by boot_kdi_tmpinit().  We're trying to restore the
124 	 * kernel's IDT that we saved on entry, but it was from the fake cpu_t
125 	 * rather than the real IDT (which is still boot's).  It's unpleasant,
126 	 * but we just encode knowledge that it's idt0 we want to restore.
127 	 */
128 	if (idt == NULL)
129 		idt = idt0;
130 
131 	CPU->cpu_m.mcpu_idt = idt;
132 	idtr.dtr_base = (uintptr_t)idt;
133 	idtr.dtr_limit = limit;
134 	kdi_idtr_write(&idtr);
135 }
136 
137 static void
138 kdi_plat_call(void (*platfn)(void))
139 {
140 	if (platfn != NULL)
141 		platfn();
142 }
143 
144 /*
145  * On Intel, most of these are shared between i86*, so this is really an
146  * arch_kdi_init().
147  */
148 void
149 mach_kdi_init(kdi_t *kdi)
150 {
151 	kdi->kdi_plat_call = kdi_plat_call;
152 	kdi->kdi_kmdb_enter = kmdb_enter;
153 	kdi->mkdi_activate = kdi_activate;
154 	kdi->mkdi_deactivate = kdi_deactivate;
155 	kdi->mkdi_idt_switch = kdi_idt_switch;
156 	kdi->mkdi_update_drreg = kdi_update_drreg;
157 	kdi->mkdi_set_debug_msrs = kdi_set_debug_msrs;
158 	kdi->mkdi_get_userlimit = kdi_get_userlimit;
159 	kdi->mkdi_get_cpuinfo = kdi_get_cpuinfo;
160 	kdi->mkdi_stop_slaves = kdi_stop_slaves;
161 	kdi->mkdi_start_slaves = kdi_start_slaves;
162 	kdi->mkdi_slave_wait = kdi_slave_wait;
163 	kdi->mkdi_memrange_add = kdi_memrange_add;
164 	kdi->mkdi_reboot = kdi_reboot;
165 }
166 
167 void
168 plat_kdi_init(kdi_t *kdi)
169 {
170 	kdi->pkdi_system_claim = kdi_system_claim;
171 	kdi->pkdi_system_release = kdi_system_release;
172 }
173