xref: /freebsd/sys/x86/pci/qpi.c (revision a64729f5077d77e13b9497cb33ecb3c82e606ee8)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
38 #include <sys/bus.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/rman.h>
43 #include <sys/systm.h>
44 
45 #include <machine/cputypes.h>
46 #include <machine/md_var.h>
47 #include <x86/legacyvar.h>
48 #include <x86/pci_cfgreg.h>
49 #include <x86/specialreg.h>
50 
51 #include <dev/pci/pcireg.h>
52 #include <dev/pci/pcivar.h>
53 #include <dev/pci/pcib_private.h>
54 #include "pcib_if.h"
55 
56 struct qpi_device {
57 	int	qd_pcibus;
58 };
59 
60 static MALLOC_DEFINE(M_QPI, "qpidrv", "qpi system device");
61 
62 static void
63 qpi_identify(driver_t *driver, device_t parent)
64 {
65 	int do_qpi;
66 
67 	/* Check CPUID to ensure this is an i7 CPU of some sort. */
68 	if (cpu_vendor_id != CPU_VENDOR_INTEL ||
69 	    CPUID_TO_FAMILY(cpu_id) != 0x6)
70 		return;
71 
72 	/* Only discover buses with configuration devices if allowed by user */
73 	do_qpi = 0;
74 	TUNABLE_INT_FETCH("hw.attach_intel_csr_pci", &do_qpi);
75 	if (!do_qpi)
76 		return;
77 
78 	/* PCI config register access is required. */
79 	if (pci_cfgregopen() == 0)
80 		return;
81 
82 	/* Add a qpi bus device. */
83 	if (BUS_ADD_CHILD(parent, 20, "qpi", -1) == NULL)
84 		panic("Failed to add qpi bus");
85 }
86 
87 static int
88 qpi_probe(device_t dev)
89 {
90 
91 	device_set_desc(dev, "QPI system bus");
92 	return (BUS_PROBE_SPECIFIC);
93 }
94 
95 /*
96  * Look for a PCI bus with the specified bus address.  If one is found,
97  * add a pcib device and return 0.  Otherwise, return an error code.
98  */
99 static int
100 qpi_probe_pcib(device_t dev, int bus)
101 {
102 	struct qpi_device *qdev;
103 	device_t child;
104 	uint32_t devid;
105 	int s;
106 
107 	/*
108 	 * If a PCI bus already exists for this bus number, then
109 	 * fail.
110 	 */
111 	if (pci_find_bsf(bus, 0, 0) != NULL)
112 		return (EEXIST);
113 
114 	/*
115 	 * Attempt to read the device id for every slot, function 0 on
116 	 * the bus.  If all read values are 0xffffffff this means that
117 	 * the bus is not present.
118 	 */
119 	for (s = 0; s <= PCI_SLOTMAX; s++) {
120 		devid = pci_cfgregread(0, bus, s, 0, PCIR_DEVVENDOR, 4);
121 		if (devid != 0xffffffff)
122 			break;
123 	}
124 	if (devid == 0xffffffff)
125 		return (ENOENT);
126 
127 	if ((devid & 0xffff) != 0x8086) {
128 		if (bootverbose)
129 			device_printf(dev,
130 			    "Device at pci%d.%d.0 has non-Intel vendor 0x%x\n",
131 			    bus, s, devid & 0xffff);
132 		return (ENXIO);
133 	}
134 
135 	child = BUS_ADD_CHILD(dev, 0, "pcib", DEVICE_UNIT_ANY);
136 	if (child == NULL)
137 		panic("%s: failed to add pci bus %d", device_get_nameunit(dev),
138 		    bus);
139 	qdev = malloc(sizeof(struct qpi_device), M_QPI, M_WAITOK);
140 	qdev->qd_pcibus = bus;
141 	device_set_ivars(child, qdev);
142 	return (0);
143 }
144 
145 static int
146 qpi_attach(device_t dev)
147 {
148 	int bus;
149 
150 	/*
151 	 * Each processor socket has a dedicated PCI bus, sometimes
152 	 * not enumerated by ACPI.  Probe all unattached buses from 0
153 	 * to 255.
154 	 */
155 	for (bus = PCI_BUSMAX; bus >= 0; bus--)
156 		qpi_probe_pcib(dev, bus);
157 
158 	return (bus_generic_attach(dev));
159 }
160 
161 static int
162 qpi_print_child(device_t bus, device_t child)
163 {
164 	struct qpi_device *qdev;
165 	int retval = 0;
166 
167 	qdev = device_get_ivars(child);
168 	retval += bus_print_child_header(bus, child);
169 	if (qdev->qd_pcibus != -1)
170 		retval += printf(" pcibus %d", qdev->qd_pcibus);
171 	retval += bus_print_child_footer(bus, child);
172 
173 	return (retval);
174 }
175 
176 static int
177 qpi_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
178 {
179 	struct qpi_device *qdev;
180 
181 	qdev = device_get_ivars(child);
182 	switch (which) {
183 	case PCIB_IVAR_BUS:
184 		*result = qdev->qd_pcibus;
185 		break;
186 	default:
187 		return (ENOENT);
188 	}
189 	return (0);
190 }
191 
192 static device_method_t qpi_methods[] = {
193 	/* Device interface */
194 	DEVMETHOD(device_identify,	qpi_identify),
195 	DEVMETHOD(device_probe,		qpi_probe),
196 	DEVMETHOD(device_attach,	qpi_attach),
197 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
198 	DEVMETHOD(device_suspend,	bus_generic_suspend),
199 	DEVMETHOD(device_resume,	bus_generic_resume),
200 
201 	/* Bus interface */
202 	DEVMETHOD(bus_print_child,	qpi_print_child),
203 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
204 	DEVMETHOD(bus_read_ivar,	qpi_read_ivar),
205 	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
206 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
207 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
208 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
209 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
210 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
211 	{ 0, 0 }
212 };
213 
214 DEFINE_CLASS_0(qpi, qpi_driver, qpi_methods, 0);
215 DRIVER_MODULE(qpi, nexus, qpi_driver, 0, 0);
216 
217 static int
218 qpi_pcib_probe(device_t dev)
219 {
220 
221 	device_set_desc(dev, "QPI Host-PCI bridge");
222 	return (BUS_PROBE_SPECIFIC);
223 }
224 
225 static int
226 qpi_pcib_attach(device_t dev)
227 {
228 
229 	device_add_child(dev, "pci", DEVICE_UNIT_ANY);
230 	return (bus_generic_attach(dev));
231 }
232 
233 static int
234 qpi_pcib_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
235 {
236 
237 	switch (which) {
238 	case PCIB_IVAR_DOMAIN:
239 		*result = 0;
240 		return (0);
241 	case PCIB_IVAR_BUS:
242 		*result = pcib_get_bus(dev);
243 		return (0);
244 	default:
245 		return (ENOENT);
246 	}
247 }
248 
249 static struct resource *
250 qpi_pcib_alloc_resource(device_t dev, device_t child, int type, int *rid,
251     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
252 {
253 
254 	if (type == PCI_RES_BUS)
255 		return (pci_domain_alloc_bus(0, child, rid, start, end, count,
256 		    flags));
257 	return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
258 	    count, flags));
259 }
260 
261 static int
262 qpi_pcib_map_msi(device_t pcib, device_t dev, int irq, uint64_t *addr,
263     uint32_t *data)
264 {
265 	device_t bus;
266 
267 	bus = device_get_parent(pcib);
268 	return (PCIB_MAP_MSI(device_get_parent(bus), dev, irq, addr, data));
269 }
270 
271 static device_method_t qpi_pcib_methods[] = {
272 	/* Device interface */
273 	DEVMETHOD(device_probe,		qpi_pcib_probe),
274 	DEVMETHOD(device_attach,	qpi_pcib_attach),
275 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
276 	DEVMETHOD(device_suspend,	bus_generic_suspend),
277 	DEVMETHOD(device_resume,	bus_generic_resume),
278 
279 	/* Bus interface */
280 	DEVMETHOD(bus_read_ivar,	qpi_pcib_read_ivar),
281 	DEVMETHOD(bus_alloc_resource,	qpi_pcib_alloc_resource),
282 	DEVMETHOD(bus_adjust_resource,	legacy_pcib_adjust_resource),
283 	DEVMETHOD(bus_release_resource,	legacy_pcib_release_resource),
284 	DEVMETHOD(bus_activate_resource, legacy_pcib_activate_resource),
285 	DEVMETHOD(bus_deactivate_resource, legacy_pcib_deactivate_resource),
286 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
287 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
288 
289 	/* pcib interface */
290 	DEVMETHOD(pcib_maxslots,	pcib_maxslots),
291 	DEVMETHOD(pcib_read_config,	legacy_pcib_read_config),
292 	DEVMETHOD(pcib_write_config,	legacy_pcib_write_config),
293 	DEVMETHOD(pcib_alloc_msi,	legacy_pcib_alloc_msi),
294 	DEVMETHOD(pcib_release_msi,	pcib_release_msi),
295 	DEVMETHOD(pcib_alloc_msix,	legacy_pcib_alloc_msix),
296 	DEVMETHOD(pcib_release_msix,	pcib_release_msix),
297 	DEVMETHOD(pcib_map_msi,		qpi_pcib_map_msi),
298 
299 	DEVMETHOD_END
300 };
301 
302 DEFINE_CLASS_0(pcib, qpi_pcib_driver, qpi_pcib_methods, 0);
303 DRIVER_MODULE(pcib, qpi, qpi_pcib_driver, 0, 0);
304