lpad.c revision 1991:f29baf5bf770 
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
38typedef 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
52static lpad_t	lpad_pool[LPAD_POOL_SIZE];
53
54#ifdef DEBUG
55static int lpad_dbg = 0;
56
57#define	LPAD_DBG		if (lpad_dbg) printf
58#define	LPAD_DUMP_DATA		lpad_dump_data
59
60static 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
68extern void mach_cpu_startup(uint64_t rabase, uint64_t memsize);
69extern void mach_cpu_startup_end(void);
70extern int promif_in_cif(void);
71
72static lpad_t *lpad_alloc(void);
73
74uint64_t *
75lpad_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
178static lpad_t *
179lpad_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
215static void
216lpad_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