xref: /titanic_50/usr/src/uts/sun4v/os/lpad.c (revision 1ae0874509b6811fdde1dfd46f0d93fd09867a3f)
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 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/machsystm.h>
31 #include <sys/machparam.h>
32 #include <sys/cmn_err.h>
33 #include <sys/cpuvar.h>
34 #include <sys/note.h>
35 #include <sys/hypervisor_api.h>
36 #include <sys/lpad.h>
37 
38 typedef struct {
39 	uint64_t	inuse;
40 	uint64_t	buf[LPAD_SIZE / sizeof (uint64_t)];
41 } lpad_t;
42 
43 /*
44  * A global pool of landing pad memory. Currently, CPUs are only
45  * brought into the system one at a time, so the pool is only a
46  * single landing pad. In the future, it may be desirable to bring
47  * CPUs into the systems in parallel. At that time, the size of
48  * the pool can be increased by changing the pool size constant.
49  */
50 #define	LPAD_POOL_SIZE	1
51 
52 static lpad_t	lpad_pool[LPAD_POOL_SIZE];
53 
54 #ifdef DEBUG
55 static int lpad_dbg = 0;
56 
57 #define	LPAD_DBG		if (lpad_dbg) printf
58 #define	LPAD_DUMP_DATA		lpad_dump_data
59 
60 static void lpad_dump_data(uint64_t *lpd_start, uint64_t *lpd_end);
61 
62 #else /* DEBUG */
63 
64 #define	LPAD_DBG		_NOTE(CONSTCOND) if (0) printf
65 #define	LPAD_DUMP_DATA
66 #endif /* DEBUG */
67 
68 extern void mach_cpu_startup(uint64_t rabase, uint64_t memsize);
69 extern void mach_cpu_startup_end(void);
70 extern int promif_in_cif(void);
71 
72 static lpad_t *lpad_alloc(void);
73 
74 uint64_t *
lpad_setup(int cpuid,uint64_t pc,uint64_t arg)75 lpad_setup(int cpuid, uint64_t pc, uint64_t arg)
76 {
77 	lpad_t		*lpp;
78 	uint64_t	textsz;
79 	uint64_t	datasz;
80 	lpad_data_t	*lpd;
81 	lpad_map_t	*lpm;
82 
83 	/* external parameters */
84 	extern caddr_t	textva;
85 	extern caddr_t	datava;
86 	extern tte_t	ktext_tte;
87 	extern tte_t	kdata_tte;
88 	extern caddr_t	mmu_fault_status_area;
89 
90 	LPAD_DBG("lpad_setup...\n");
91 
92 	if ((cpuid < 0) || (cpuid > NCPU)) {
93 		cmn_err(CE_PANIC, "lpad_setup: invalid cpuid");
94 	}
95 
96 	/* allocate our landing pad */
97 	if ((lpp = lpad_alloc()) == NULL) {
98 		cmn_err(CE_PANIC, "lpad_setup: unable to allocate lpad");
99 	}
100 
101 	/* calculate the size of our text */
102 	textsz = (uint64_t)mach_cpu_startup_end - (uint64_t)mach_cpu_startup;
103 
104 	LPAD_DBG("lpad textsz=%ld\n", textsz);
105 
106 	ASSERT(textsz <= LPAD_TEXT_SIZE);
107 
108 	/* copy over text section */
109 	bcopy((void *)mach_cpu_startup, lpp->buf, textsz);
110 
111 	lpd = (lpad_data_t *)(((caddr_t)lpp->buf) + LPAD_TEXT_SIZE);
112 	lpm = (lpad_map_t *)lpd->map;
113 
114 	ASSERT(mmu_fault_status_area);
115 
116 	bzero(lpd, LPAD_TEXT_SIZE);
117 	lpd->magic = LPAD_MAGIC_VAL;
118 	lpd->inuse = &(lpp->inuse);
119 	lpd->mmfsa_ra = va_to_pa(mmu_fault_status_area) + (MMFSA_SIZE * cpuid);
120 	lpd->pc = pc;
121 	lpd->arg = arg;
122 
123 	/*
124 	 * List of mappings:
125 	 *
126 	 *    - permanent inst/data mapping for kernel text
127 	 *    - permanent data mapping for kernel data
128 	 *    - non-permanent inst mapping for kernel data,
129 	 *	required for landing pad text
130 	 */
131 	lpd->nmap = 3;
132 
133 	/* verify the lpad has enough room for the data */
134 	datasz = sizeof (lpad_data_t);
135 	datasz += (lpd->nmap - 1) * sizeof (lpad_map_t);
136 
137 	ASSERT(datasz <= LPAD_DATA_SIZE);
138 
139 	/*
140 	 * Kernel Text Mapping
141 	 */
142 	lpm->va = (uint64_t)textva;
143 	lpm->tte = ktext_tte;
144 	lpm->flag_mmuflags = (MAP_ITLB | MAP_DTLB);
145 	lpm->flag_perm = 1;
146 	lpm++;
147 
148 	/*
149 	 * Kernel Data Mapping
150 	 */
151 	lpm->va = (uint64_t)datava;
152 	lpm->tte = kdata_tte;
153 	lpm->flag_mmuflags = MAP_DTLB;
154 	lpm->flag_perm = 1;
155 	lpm++;
156 
157 	/*
158 	 * Landing Pad Text Mapping
159 	 *
160 	 * Because this mapping should not be permanent,
161 	 * the permanent mapping above cannot be used.
162 	 */
163 	lpm->va = (uint64_t)datava;
164 	lpm->tte = kdata_tte;
165 	lpm->flag_mmuflags = MAP_ITLB;
166 	lpm->flag_perm = 0;
167 	lpm++;
168 
169 	ASSERT(((uint64_t)lpm - (uint64_t)lpd) == datasz);
170 
171 	LPAD_DBG("copied %ld bytes of data into lpad\n", datasz);
172 
173 	LPAD_DUMP_DATA((uint64_t *)lpd, (uint64_t *)lpm);
174 
175 	return (lpp->buf);
176 }
177 
178 static lpad_t *
lpad_alloc(void)179 lpad_alloc(void)
180 {
181 	int	idx;
182 
183 	/*
184 	 * No locking is required for the global lpad pool since
185 	 * it should only be accessed while in the CIF which is
186 	 * single threaded. If this assumption changes, locking
187 	 * would be required.
188 	 */
189 	ASSERT(promif_in_cif());
190 
191 	/*
192 	 * Wait until an lpad buffer becomes available.
193 	 */
194 	for (;;) {
195 		LPAD_DBG("checking lpad pool:\n");
196 
197 		/* walk the lpad buffer array */
198 		for (idx = 0; idx < LPAD_POOL_SIZE; idx++) {
199 
200 			LPAD_DBG("\tchecking lpad_pool[%d]\n", idx);
201 
202 			if (lpad_pool[idx].inuse == 0) {
203 				LPAD_DBG("found empty lpad (%d)\n", idx);
204 
205 				/* mark the buffer as busy */
206 				lpad_pool[idx].inuse = 1;
207 
208 				return (&lpad_pool[idx]);
209 			}
210 		}
211 	}
212 }
213 
214 #ifdef DEBUG
215 static void
lpad_dump_data(uint64_t * lpd_start,uint64_t * lpd_end)216 lpad_dump_data(uint64_t *lpd_start, uint64_t *lpd_end)
217 {
218 	uint64_t	*lp;
219 	uint_t		offset = 0;
220 
221 	if (lpad_dbg == 0)
222 		return;
223 
224 	printf("lpad data:\n");
225 
226 	for (lp = lpd_start; lp < lpd_end; lp++) {
227 		printf("\t0x%02x  0x%016lx\n", offset, *lp);
228 		offset += sizeof (uint64_t);
229 	}
230 }
231 #endif /* DEBUG */
232