xref: /freebsd/sys/x86/pci/qpi.c (revision 8881d206f4e68b564c2c5f50fc717086fc3e827a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010 Hudson River Trading LLC
5  * Written by: John H. Baldwin <jhb@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * This driver provides a pseudo-bus to enumerate the PCI buses
32  * present on a system using a QPI chipset.  It creates a qpi0 bus that
33  * is a child of nexus0 and then creates Host-PCI bridges as a
34  * child of that.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 #include <sys/bus.h>
42 #include <sys/kernel.h>
43 #include <sys/malloc.h>
44 #include <sys/module.h>
45 #include <sys/rman.h>
46 #include <sys/systm.h>
47 
48 #include <machine/cputypes.h>
49 #include <machine/md_var.h>
50 #include <x86/legacyvar.h>
51 #include <x86/pci_cfgreg.h>
52 #include <x86/specialreg.h>
53 
54 #include <dev/pci/pcireg.h>
55 #include <dev/pci/pcivar.h>
56 #include <dev/pci/pcib_private.h>
57 #include "pcib_if.h"
58 
59 struct qpi_device {
60 	int	qd_pcibus;
61 };
62 
63 static MALLOC_DEFINE(M_QPI, "qpidrv", "qpi system device");
64 
65 static void
66 qpi_identify(driver_t *driver, device_t parent)
67 {
68 	int do_qpi;
69 
70 	/* Check CPUID to ensure this is an i7 CPU of some sort. */
71 	if (cpu_vendor_id != CPU_VENDOR_INTEL ||
72 	    CPUID_TO_FAMILY(cpu_id) != 0x6)
73 		return;
74 
75 	/* Only discover buses with configuration devices if allowed by user */
76 	do_qpi = 0;
77 	TUNABLE_INT_FETCH("hw.attach_intel_csr_pci", &do_qpi);
78 	if (!do_qpi)
79 		return;
80 
81 	/* PCI config register access is required. */
82 	if (pci_cfgregopen() == 0)
83 		return;
84 
85 	/* Add a qpi bus device. */
86 	if (BUS_ADD_CHILD(parent, 20, "qpi", -1) == NULL)
87 		panic("Failed to add qpi bus");
88 }
89 
90 static int
91 qpi_probe(device_t dev)
92 {
93 
94 	device_set_desc(dev, "QPI system bus");
95 	return (BUS_PROBE_SPECIFIC);
96 }
97 
98 /*
99  * Look for a PCI bus with the specified bus address.  If one is found,
100  * add a pcib device and return 0.  Otherwise, return an error code.
101  */
102 static int
103 qpi_probe_pcib(device_t dev, int bus)
104 {
105 	struct qpi_device *qdev;
106 	device_t child;
107 	uint32_t devid;
108 	int s;
109 
110 	/*
111 	 * If a PCI bus already exists for this bus number, then
112 	 * fail.
113 	 */
114 	if (pci_find_bsf(bus, 0, 0) != NULL)
115 		return (EEXIST);
116 
117 	/*
118 	 * Attempt to read the device id for every slot, function 0 on
119 	 * the bus.  If all read values are 0xffffffff this means that
120 	 * the bus is not present.
121 	 */
122 	for (s = 0; s <= PCI_SLOTMAX; s++) {
123 		devid = pci_cfgregread(bus, s, 0, PCIR_DEVVENDOR, 4);
124 		if (devid != 0xffffffff)
125 			break;
126 	}
127 	if (devid == 0xffffffff)
128 		return (ENOENT);
129 
130 	if ((devid & 0xffff) != 0x8086) {
131 		if (bootverbose)
132 			device_printf(dev,
133 			    "Device at pci%d.%d.0 has non-Intel vendor 0x%x\n",
134 			    bus, s, devid & 0xffff);
135 		return (ENXIO);
136 	}
137 
138 	child = BUS_ADD_CHILD(dev, 0, "pcib", -1);
139 	if (child == NULL)
140 		panic("%s: failed to add pci bus %d", device_get_nameunit(dev),
141 		    bus);
142 	qdev = malloc(sizeof(struct qpi_device), M_QPI, M_WAITOK);
143 	qdev->qd_pcibus = bus;
144 	device_set_ivars(child, qdev);
145 	return (0);
146 }
147 
148 static int
149 qpi_attach(device_t dev)
150 {
151 	int bus;
152 
153 	/*
154 	 * Each processor socket has a dedicated PCI bus, sometimes
155 	 * not enumerated by ACPI.  Probe all unattached buses from 0
156 	 * to 255.
157 	 */
158 	for (bus = PCI_BUSMAX; bus >= 0; bus--)
159 		qpi_probe_pcib(dev, bus);
160 
161 	return (bus_generic_attach(dev));
162 }
163 
164 static int
165 qpi_print_child(device_t bus, device_t child)
166 {
167 	struct qpi_device *qdev;
168 	int retval = 0;
169 
170 	qdev = device_get_ivars(child);
171 	retval += bus_print_child_header(bus, child);
172 	if (qdev->qd_pcibus != -1)
173 		retval += printf(" pcibus %d", qdev->qd_pcibus);
174 	retval += bus_print_child_footer(bus, child);
175 
176 	return (retval);
177 }
178 
179 static int
180 qpi_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
181 {
182 	struct qpi_device *qdev;
183 
184 	qdev = device_get_ivars(child);
185 	switch (which) {
186 	case PCIB_IVAR_BUS:
187 		*result = qdev->qd_pcibus;
188 		break;
189 	default:
190 		return (ENOENT);
191 	}
192 	return (0);
193 }
194 
195 static device_method_t qpi_methods[] = {
196 	/* Device interface */
197 	DEVMETHOD(device_identify,	qpi_identify),
198 	DEVMETHOD(device_probe,		qpi_probe),
199 	DEVMETHOD(device_attach,	qpi_attach),
200 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
201 	DEVMETHOD(device_suspend,	bus_generic_suspend),
202 	DEVMETHOD(device_resume,	bus_generic_resume),
203 
204 	/* Bus interface */
205 	DEVMETHOD(bus_print_child,	qpi_print_child),
206 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
207 	DEVMETHOD(bus_read_ivar,	qpi_read_ivar),
208 	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
209 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
210 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
211 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
212 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
213 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
214 	{ 0, 0 }
215 };
216 
217 static devclass_t qpi_devclass;
218 
219 DEFINE_CLASS_0(qpi, qpi_driver, qpi_methods, 0);
220 DRIVER_MODULE(qpi, nexus, qpi_driver, qpi_devclass, 0, 0);
221 
222 static int
223 qpi_pcib_probe(device_t dev)
224 {
225 
226 	device_set_desc(dev, "QPI Host-PCI bridge");
227 	return (BUS_PROBE_SPECIFIC);
228 }
229 
230 static int
231 qpi_pcib_attach(device_t dev)
232 {
233 
234 	device_add_child(dev, "pci", -1);
235 	return (bus_generic_attach(dev));
236 }
237 
238 static int
239 qpi_pcib_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
240 {
241 
242 	switch (which) {
243 	case PCIB_IVAR_DOMAIN:
244 		*result = 0;
245 		return (0);
246 	case PCIB_IVAR_BUS:
247 		*result = pcib_get_bus(dev);
248 		return (0);
249 	default:
250 		return (ENOENT);
251 	}
252 }
253 
254 #if defined(NEW_PCIB) && defined(PCI_RES_BUS)
255 static struct resource *
256 qpi_pcib_alloc_resource(device_t dev, device_t child, int type, int *rid,
257     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
258 {
259 
260 	if (type == PCI_RES_BUS)
261 		return (pci_domain_alloc_bus(0, child, rid, start, end, count,
262 		    flags));
263 	return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
264 	    count, flags));
265 }
266 #endif
267 
268 static int
269 qpi_pcib_map_msi(device_t pcib, device_t dev, int irq, uint64_t *addr,
270     uint32_t *data)
271 {
272 	device_t bus;
273 
274 	bus = device_get_parent(pcib);
275 	return (PCIB_MAP_MSI(device_get_parent(bus), dev, irq, addr, data));
276 }
277 
278 static device_method_t qpi_pcib_methods[] = {
279 	/* Device interface */
280 	DEVMETHOD(device_probe,		qpi_pcib_probe),
281 	DEVMETHOD(device_attach,	qpi_pcib_attach),
282 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
283 	DEVMETHOD(device_suspend,	bus_generic_suspend),
284 	DEVMETHOD(device_resume,	bus_generic_resume),
285 
286 	/* Bus interface */
287 	DEVMETHOD(bus_read_ivar,	qpi_pcib_read_ivar),
288 #if defined(NEW_PCIB) && defined(PCI_RES_BUS)
289 	DEVMETHOD(bus_alloc_resource,	qpi_pcib_alloc_resource),
290 	DEVMETHOD(bus_adjust_resource,	legacy_pcib_adjust_resource),
291 	DEVMETHOD(bus_release_resource,	legacy_pcib_release_resource),
292 #else
293 	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
294 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
295 #endif
296 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
297 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
298 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
299 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
300 
301 	/* pcib interface */
302 	DEVMETHOD(pcib_maxslots,	pcib_maxslots),
303 	DEVMETHOD(pcib_read_config,	legacy_pcib_read_config),
304 	DEVMETHOD(pcib_write_config,	legacy_pcib_write_config),
305 	DEVMETHOD(pcib_alloc_msi,	legacy_pcib_alloc_msi),
306 	DEVMETHOD(pcib_release_msi,	pcib_release_msi),
307 	DEVMETHOD(pcib_alloc_msix,	legacy_pcib_alloc_msix),
308 	DEVMETHOD(pcib_release_msix,	pcib_release_msix),
309 	DEVMETHOD(pcib_map_msi,		qpi_pcib_map_msi),
310 
311 	DEVMETHOD_END
312 };
313 
314 static devclass_t qpi_pcib_devclass;
315 
316 DEFINE_CLASS_0(pcib, qpi_pcib_driver, qpi_pcib_methods, 0);
317 DRIVER_MODULE(pcib, qpi, qpi_pcib_driver, qpi_pcib_devclass, 0, 0);
318