xref: /illumos-gate/usr/src/uts/i86pc/os/pci_bios.c (revision c3937c08b16d32677a7dc955a81325f2e7a61b5d)
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  * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright 2020 OmniOS Community Edition (OmniOSce) Association.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/sunndi.h>
29 #include <sys/pci.h>
30 #include <sys/pci_impl.h>
31 #include <sys/pci_cfgspace.h>
32 #include <sys/pci_cfgspace_impl.h>
33 #include <sys/memlist.h>
34 #include <sys/bootconf.h>
35 #include <sys/psw.h>
36 
37 /*
38  * pci irq routing information table
39  */
40 int				pci_irq_nroutes;
41 static pci_irq_route_t		*pci_irq_routes;
42 
43 
44 static int pci_bios_get_irq_routing(pci_irq_route_t *, int, int *);
45 static void pci_get_irq_routing_table(void);
46 
47 
48 /*
49  * Retrieve information from the bios needed for system
50  * configuration early during startup.
51  */
52 void
53 startup_pci_bios(void)
54 {
55 	pci_get_irq_routing_table();
56 }
57 
58 
59 /*
60  * Issue the bios get irq routing information table interrupt
61  *
62  * Despite the name, the information in the table is only
63  * used to derive slot names for some named pci hot-plug slots.
64  *
65  * Returns the number of irq routing table entries returned
66  * by the bios, or 0 and optionally, the number of entries required.
67  */
68 static int
69 pci_bios_get_irq_routing(pci_irq_route_t *routes, int nroutes, int *nneededp)
70 {
71 	struct bop_regs regs;
72 	uchar_t		*hdrp;
73 	uchar_t		*bufp;
74 	int		i, n;
75 	int		rval = 0;
76 
77 	if (nneededp)
78 		*nneededp = 0;
79 
80 	/* in UEFI system, there is no BIOS data */
81 	if (BOP_GETPROPLEN(bootops, "efi-systab") > 0)
82 		return (0);
83 
84 	/*
85 	 * Set up irq routing header with the size and address
86 	 * of some useable low-memory data addresses.  Initalize
87 	 * data area to zero, avoiding memcpy/bzero.
88 	 */
89 	hdrp = (uchar_t *)BIOS_IRQ_ROUTING_HDR;
90 	bufp = (uchar_t *)BIOS_IRQ_ROUTING_DATA;
91 
92 	n = nroutes * sizeof (pci_irq_route_t);
93 	for (i = 0; i < n; i++)
94 		bufp[i] = 0;
95 	((pci_irq_route_hdr_t *)hdrp)->pir_size = n;
96 	((pci_irq_route_hdr_t *)hdrp)->pir_addr = (uint32_t)(uintptr_t)bufp;
97 
98 	bzero(&regs, sizeof (regs));
99 	regs.eax.word.ax = (PCI_FUNCTION_ID << 8) | PCI_GET_IRQ_ROUTING;
100 
101 	regs.ds = 0xf000;
102 	regs.es = FP_SEG((uint_t)(uintptr_t)hdrp);
103 	regs.edi.word.di = FP_OFF((uint_t)(uintptr_t)hdrp);
104 
105 	BOP_DOINT(bootops, 0x1a, &regs);
106 
107 	n = (int)(((pci_irq_route_hdr_t *)hdrp)->pir_size /
108 	    sizeof (pci_irq_route_t));
109 
110 	if ((regs.eflags & PS_C) != 0) {
111 		if (nneededp)
112 			*nneededp = n;
113 	} else {
114 		/*
115 		 * Copy resulting irq routing data from low memory up to
116 		 * the kernel address space, avoiding memcpy as usual.
117 		 */
118 		if (n <= nroutes) {
119 			for (i = 0; i < n * sizeof (pci_irq_route_t); i++)
120 				((uchar_t *)routes)[i] = bufp[i];
121 			rval = n;
122 		}
123 	}
124 	return (rval);
125 }
126 
127 static void
128 pci_get_irq_routing_table(void)
129 {
130 	pci_irq_route_t	*routes;
131 	int		n = N_PCI_IRQ_ROUTES;
132 	int		nneeded = 0;
133 	int		nroutes;
134 
135 	/*
136 	 * Get irq routing table information.
137 	 * Allocate a buffer for an initial default number of entries.
138 	 * If the bios indicates it needs a larger buffer, try it again.
139 	 * Drive on if it still won't cooperate and play nice after that.
140 	 */
141 	routes = kmem_zalloc(n * sizeof (pci_irq_route_t), KM_SLEEP);
142 	nroutes = pci_bios_get_irq_routing(routes, n, &nneeded);
143 	if (nroutes == 0 && nneeded > n) {
144 		kmem_free(routes, n * sizeof (pci_irq_route_t));
145 		if (nneeded > N_PCI_IRQ_ROUTES_MAX) {
146 			cmn_err(CE_CONT,
147 			    "pci: unable to get IRQ routing information, "
148 			    "required buffer space of %d entries exceeds max\n",
149 			    nneeded);
150 			return;
151 		}
152 		n = nneeded;
153 		routes = kmem_zalloc(n * sizeof (pci_irq_route_t), KM_SLEEP);
154 		nroutes = pci_bios_get_irq_routing(routes, n, NULL);
155 		if (nroutes == 0) {
156 			cmn_err(CE_CONT,
157 			    "pci: unable to get IRQ routing information, "
158 			    "required buffer space for %d entries\n", n);
159 		}
160 	}
161 
162 	if (nroutes > 0) {
163 		pci_irq_routes = routes;
164 		pci_irq_nroutes = nroutes;
165 	} else {
166 		kmem_free(routes, n * sizeof (pci_irq_route_t));
167 	}
168 }
169 
170 /*
171  * Use the results of the PCI BIOS call that returned the routing tables
172  * to build the 1275 slot-names property for the indicated bus.
173  * Results are returned in buf.  Length is return value, -1 is returned on
174  * overflow and zero is returned if no data exists to build a property.
175  */
176 int
177 pci_slot_names_prop(int bus, char *buf, int len)
178 {
179 	uchar_t		dev;
180 	uchar_t		slot[N_PCI_IRQ_ROUTES_MAX+1];
181 	uint32_t	 mask;
182 	int		i, nnames, plen;
183 
184 	ASSERT(pci_irq_nroutes <= N_PCI_IRQ_ROUTES_MAX);
185 
186 	if (pci_irq_nroutes == 0)
187 		return (0);
188 	nnames = 0;
189 	mask = 0;
190 	for (i = 0; i < pci_irq_nroutes; i++)
191 		slot[i] = 0xff;
192 	for (i = 0; i < pci_irq_nroutes; i++) {
193 		if (pci_irq_routes[i].pir_bus != bus)
194 			continue;
195 		if (pci_irq_routes[i].pir_slot != 0) {
196 			dev = (pci_irq_routes[i].pir_dev & 0xf8) >> 3;
197 			slot[dev] = pci_irq_routes[i].pir_slot;
198 			mask |= (1 << dev);
199 			nnames++;
200 		}
201 	}
202 
203 	if (nnames == 0)
204 		return (0);
205 
206 	if (len < (4 + nnames * 8))
207 		return (-1);
208 	*(uint32_t *)buf = mask;
209 	plen = 4;
210 	for (i = 0; i < pci_irq_nroutes; i++) {
211 		if (slot[i] == 0xff)
212 			continue;
213 		(void) sprintf(buf + plen, "Slot%d", slot[i]);
214 		plen += strlen(buf+plen) + 1;
215 		*(buf + plen) = 0;
216 	}
217 	for (; plen % 4; plen++)
218 		*(buf + plen) = 0;
219 	return (plen);
220 }
221