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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /*
27 * PCI configuration space access routines
28 */
29
30 #include <sys/systm.h>
31 #include <sys/psw.h>
32 #include <sys/bootconf.h>
33 #include <sys/reboot.h>
34 #include <sys/pci_impl.h>
35 #include <sys/pci_cfgspace.h>
36 #include <sys/pci_cfgspace_impl.h>
37 #include <sys/pci_cfgacc.h>
38 #if defined(__xpv)
39 #include <sys/hypervisor.h>
40 #endif
41
42 #if defined(__xpv)
43 int pci_max_nbus = 0xFE;
44 #endif
45 int pci_bios_cfg_type = PCI_MECHANISM_UNKNOWN;
46 int pci_bios_maxbus;
47 int pci_bios_mech;
48 int pci_bios_vers;
49
50 /*
51 * These two variables can be used to force a configuration mechanism or
52 * to force which function is used to probe for the presence of the PCI bus.
53 */
54 int PCI_CFG_TYPE = 0;
55 int PCI_PROBE_TYPE = 0;
56
57 /*
58 * No valid mcfg_mem_base by default, and accessing pci config space
59 * in mem-mapped way is disabled.
60 */
61 uint64_t mcfg_mem_base = 0;
62 uint8_t mcfg_bus_start = 0;
63 uint8_t mcfg_bus_end = 0xff;
64
65 /*
66 * Maximum offset in config space when not using MMIO
67 */
68 uint_t pci_iocfg_max_offset = 0xff;
69
70 /*
71 * These function pointers lead to the actual implementation routines
72 * for configuration space access. Normally they lead to either the
73 * pci_mech1_* or pci_mech2_* routines, but they can also lead to
74 * routines that work around chipset bugs.
75 * These functions are accessing pci config space via I/O way.
76 * Pci_cfgacc_get/put functions shoul be used as more common interfaces,
77 * which also provide accessing pci config space via mem-mapped way.
78 */
79 uint8_t (*pci_getb_func)(int bus, int dev, int func, int reg);
80 uint16_t (*pci_getw_func)(int bus, int dev, int func, int reg);
81 uint32_t (*pci_getl_func)(int bus, int dev, int func, int reg);
82 void (*pci_putb_func)(int bus, int dev, int func, int reg, uint8_t val);
83 void (*pci_putw_func)(int bus, int dev, int func, int reg, uint16_t val);
84 void (*pci_putl_func)(int bus, int dev, int func, int reg, uint32_t val);
85
86 extern void (*pci_cfgacc_acc_p)(pci_cfgacc_req_t *req);
87
88 /*
89 * Internal routines
90 */
91 static int pci_check(void);
92
93 #if !defined(__xpv)
94 static int pci_check_bios(void);
95 static int pci_get_cfg_type(void);
96 #endif
97
98 /* for legacy io-based config space access */
99 kmutex_t pcicfg_mutex;
100
101 /* for mmio-based config space access */
102 kmutex_t pcicfg_mmio_mutex;
103
104 /* ..except Orion and Neptune, which have to have their own */
105 kmutex_t pcicfg_chipset_mutex;
106
107 void
pci_cfgspace_init(void)108 pci_cfgspace_init(void)
109 {
110 mutex_init(&pcicfg_mutex, NULL, MUTEX_SPIN,
111 (ddi_iblock_cookie_t)ipltospl(15));
112 mutex_init(&pcicfg_mmio_mutex, NULL, MUTEX_SPIN,
113 (ddi_iblock_cookie_t)ipltospl(DISP_LEVEL));
114 mutex_init(&pcicfg_chipset_mutex, NULL, MUTEX_SPIN,
115 (ddi_iblock_cookie_t)ipltospl(15));
116 if (!pci_check()) {
117 mutex_destroy(&pcicfg_mutex);
118 mutex_destroy(&pcicfg_mmio_mutex);
119 mutex_destroy(&pcicfg_chipset_mutex);
120 }
121 }
122
123 /*
124 * This code determines if this system supports PCI/PCIE and which
125 * type of configuration access method is used
126 */
127 static int
pci_check(void)128 pci_check(void)
129 {
130 uint64_t ecfginfo[4];
131
132 /*
133 * Only do this once. NB: If this is not a PCI system, and we
134 * get called twice, we can't detect it and will probably die
135 * horribly when we try to ask the BIOS whether PCI is present.
136 * This code is safe *ONLY* during system startup when the
137 * BIOS is still available.
138 */
139 if (pci_bios_cfg_type != PCI_MECHANISM_UNKNOWN)
140 return (TRUE);
141
142 #if defined(__xpv)
143 /*
144 * only support PCI config mechanism 1 in i86xpv. This should be fine
145 * since the other ones are workarounds for old broken H/W which won't
146 * be supported in i86xpv anyway.
147 */
148 if (DOMAIN_IS_INITDOMAIN(xen_info)) {
149 pci_bios_cfg_type = PCI_MECHANISM_1;
150 pci_getb_func = pci_mech1_getb;
151 pci_getw_func = pci_mech1_getw;
152 pci_getl_func = pci_mech1_getl;
153 pci_putb_func = pci_mech1_putb;
154 pci_putw_func = pci_mech1_putw;
155 pci_putl_func = pci_mech1_putl;
156
157 /*
158 * Since we can't get the BIOS info in i86xpv, we will do an
159 * exhaustive search of all PCI buses. We have to do this until
160 * we start using the PCI information in ACPI.
161 */
162 pci_bios_maxbus = pci_max_nbus;
163 }
164 #else /* !__xpv */
165
166 pci_bios_cfg_type = pci_check_bios();
167
168 if (pci_bios_cfg_type == PCI_MECHANISM_NONE)
169 pci_bios_cfg_type = PCI_MECHANISM_1; /* default to mech 1 */
170
171 switch (pci_get_cfg_type()) {
172 case PCI_MECHANISM_1:
173 if (pci_is_broken_orion()) {
174 pci_getb_func = pci_orion_getb;
175 pci_getw_func = pci_orion_getw;
176 pci_getl_func = pci_orion_getl;
177 pci_putb_func = pci_orion_putb;
178 pci_putw_func = pci_orion_putw;
179 pci_putl_func = pci_orion_putl;
180 } else if (pci_check_amd_ioecs()) {
181 pci_getb_func = pci_mech1_amd_getb;
182 pci_getw_func = pci_mech1_amd_getw;
183 pci_getl_func = pci_mech1_amd_getl;
184 pci_putb_func = pci_mech1_amd_putb;
185 pci_putw_func = pci_mech1_amd_putw;
186 pci_putl_func = pci_mech1_amd_putl;
187 pci_iocfg_max_offset = 0xfff;
188 } else {
189 pci_getb_func = pci_mech1_getb;
190 pci_getw_func = pci_mech1_getw;
191 pci_getl_func = pci_mech1_getl;
192 pci_putb_func = pci_mech1_putb;
193 pci_putw_func = pci_mech1_putw;
194 pci_putl_func = pci_mech1_putl;
195 }
196 break;
197
198 case PCI_MECHANISM_2:
199 if (pci_check_neptune()) {
200 /*
201 * The BIOS for some systems with the Intel
202 * Neptune chipset seem to default to #2 even
203 * though the chipset can do #1. Override
204 * the BIOS so that MP systems will work
205 * correctly.
206 */
207
208 pci_getb_func = pci_neptune_getb;
209 pci_getw_func = pci_neptune_getw;
210 pci_getl_func = pci_neptune_getl;
211 pci_putb_func = pci_neptune_putb;
212 pci_putw_func = pci_neptune_putw;
213 pci_putl_func = pci_neptune_putl;
214 } else {
215 pci_getb_func = pci_mech2_getb;
216 pci_getw_func = pci_mech2_getw;
217 pci_getl_func = pci_mech2_getl;
218 pci_putb_func = pci_mech2_putb;
219 pci_putw_func = pci_mech2_putw;
220 pci_putl_func = pci_mech2_putl;
221 }
222 break;
223
224 default:
225 return (FALSE);
226 }
227 #endif /* __xpv */
228
229 /*
230 * Try to get a valid mcfg_mem_base in early boot
231 * If failed, leave mem-mapped pci config space accessing disabled
232 * until pci boot code (pci_autoconfig) makes sure this is a PCIE
233 * platform.
234 */
235 if (do_bsys_getprop(NULL, MCFG_PROPNAME, ecfginfo) != -1) {
236 mcfg_mem_base = ecfginfo[0];
237 mcfg_bus_start = ecfginfo[2];
238 mcfg_bus_end = ecfginfo[3];
239 }
240
241 /* See pci_cfgacc.c */
242 pci_cfgacc_acc_p = pci_cfgacc_acc;
243
244 return (TRUE);
245 }
246
247 #if !defined(__xpv)
248
249 static int
pci_check_bios(void)250 pci_check_bios(void)
251 {
252 struct bop_regs regs;
253 uint32_t carryflag;
254 uint16_t ax, dx;
255
256 bzero(®s, sizeof (regs));
257 regs.eax.word.ax = (PCI_FUNCTION_ID << 8) | PCI_BIOS_PRESENT;
258
259 BOP_DOINT(bootops, 0x1a, ®s);
260 carryflag = regs.eflags & PS_C;
261 ax = regs.eax.word.ax;
262 dx = regs.edx.word.dx;
263
264 /* the carry flag must not be set */
265 if (carryflag != 0)
266 return (PCI_MECHANISM_NONE);
267
268 if (dx != ('P' | 'C'<<8))
269 return (PCI_MECHANISM_NONE);
270
271 /* ah (the high byte of ax) must be zero */
272 if ((ax & 0xff00) != 0)
273 return (PCI_MECHANISM_NONE);
274
275 pci_bios_mech = (ax & 0x3);
276 pci_bios_vers = regs.ebx.word.bx;
277 pci_bios_maxbus = (regs.ecx.word.cx & 0xff);
278
279 switch (pci_bios_mech) {
280 default: /* ?!? */
281 case 0: /* supports neither? */
282 return (PCI_MECHANISM_NONE);
283
284 case 1:
285 case 3: /* supports both */
286 return (PCI_MECHANISM_1);
287
288 case 2:
289 return (PCI_MECHANISM_2);
290 }
291 }
292
293 static int
pci_get_cfg_type(void)294 pci_get_cfg_type(void)
295 {
296 /* Check to see if the config mechanism has been set in /etc/system */
297 switch (PCI_CFG_TYPE) {
298 default:
299 case 0:
300 break;
301 case 1:
302 return (PCI_MECHANISM_1);
303 case 2:
304 return (PCI_MECHANISM_2);
305 case -1:
306 return (PCI_MECHANISM_NONE);
307 }
308
309 /* call one of the PCI detection algorithms */
310 switch (PCI_PROBE_TYPE) {
311 default:
312 case 0:
313 /* From pci_check() and pci_check_bios() */
314 return (pci_bios_cfg_type);
315 case -1:
316 return (PCI_MECHANISM_NONE);
317 }
318 }
319
320 #endif /* __xpv */
321