xref: /titanic_41/usr/src/uts/i86pc/os/pci_bios.c (revision 4445fffbbb1ea25fd0e9ea68b9380dd7a6709025)
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  */
24 
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/sunndi.h>
28 #include <sys/pci.h>
29 #include <sys/pci_impl.h>
30 #include <sys/pci_cfgspace.h>
31 #include <sys/pci_cfgspace_impl.h>
32 #include <sys/memlist.h>
33 #include <sys/bootconf.h>
34 #include <sys/psw.h>
35 
36 /*
37  * pci irq routing information table
38  */
39 int				pci_irq_nroutes;
40 static pci_irq_route_t		*pci_irq_routes;
41 
42 
43 static int pci_bios_get_irq_routing(pci_irq_route_t *, int, int *);
44 static void pci_get_irq_routing_table(void);
45 
46 
47 /*
48  * Retrieve information from the bios needed for system
49  * configuration early during startup.
50  */
51 void
52 startup_pci_bios(void)
53 {
54 	pci_get_irq_routing_table();
55 }
56 
57 
58 /*
59  * Issue the bios get irq routing information table interrupt
60  *
61  * Despite the name, the information in the table is only
62  * used to derive slot names for some named pci hot-plug slots.
63  *
64  * Returns the number of irq routing table entries returned
65  * by the bios, or 0 and optionally, the number of entries required.
66  */
67 static int
68 pci_bios_get_irq_routing(pci_irq_route_t *routes, int nroutes, int *nneededp)
69 {
70 	struct bop_regs regs;
71 	uchar_t		*hdrp;
72 	uchar_t		*bufp;
73 	int 		i, n;
74 	int		rval = 0;
75 
76 	if (nneededp)
77 		*nneededp = 0;
78 
79 	/*
80 	 * Set up irq routing header with the size and address
81 	 * of some useable low-memory data addresses.  Initalize
82 	 * data area to zero, avoiding memcpy/bzero.
83 	 */
84 	hdrp = (uchar_t *)BIOS_IRQ_ROUTING_HDR;
85 	bufp = (uchar_t *)BIOS_IRQ_ROUTING_DATA;
86 
87 	n = nroutes * sizeof (pci_irq_route_t);
88 	for (i = 0; i < n; i++)
89 		bufp[i] = 0;
90 	((pci_irq_route_hdr_t *)hdrp)->pir_size = n;
91 	((pci_irq_route_hdr_t *)hdrp)->pir_addr = (uint32_t)(uintptr_t)bufp;
92 
93 	bzero(&regs, sizeof (regs));
94 	regs.eax.word.ax = (PCI_FUNCTION_ID << 8) | PCI_GET_IRQ_ROUTING;
95 
96 	regs.ds = 0xf000;
97 	regs.es = FP_SEG((uint_t)(uintptr_t)hdrp);
98 	regs.edi.word.di = FP_OFF((uint_t)(uintptr_t)hdrp);
99 
100 	BOP_DOINT(bootops, 0x1a, &regs);
101 
102 	n = (int)(((pci_irq_route_hdr_t *)hdrp)->pir_size /
103 	    sizeof (pci_irq_route_t));
104 
105 	if ((regs.eflags & PS_C) != 0) {
106 		if (nneededp)
107 			*nneededp = n;
108 	} else {
109 		/*
110 		 * Copy resulting irq routing data from low memory up to
111 		 * the kernel address space, avoiding memcpy as usual.
112 		 */
113 		if (n <= nroutes) {
114 			for (i = 0; i < n * sizeof (pci_irq_route_t); i++)
115 				((uchar_t *)routes)[i] = bufp[i];
116 			rval = n;
117 		}
118 	}
119 	return (rval);
120 }
121 
122 static void
123 pci_get_irq_routing_table(void)
124 {
125 	pci_irq_route_t	*routes;
126 	int		n = N_PCI_IRQ_ROUTES;
127 	int		nneeded = 0;
128 	int		nroutes;
129 
130 	/*
131 	 * Get irq routing table information.
132 	 * Allocate a buffer for an initial default number of entries.
133 	 * If the bios indicates it needs a larger buffer, try it again.
134 	 * Drive on if it still won't cooperate and play nice after that.
135 	 */
136 	routes = kmem_zalloc(n * sizeof (pci_irq_route_t), KM_SLEEP);
137 	nroutes = pci_bios_get_irq_routing(routes, n, &nneeded);
138 	if (nroutes == 0 && nneeded > n) {
139 		kmem_free(routes, n * sizeof (pci_irq_route_t));
140 		if (nneeded > N_PCI_IRQ_ROUTES_MAX) {
141 			cmn_err(CE_CONT,
142 			    "pci: unable to get IRQ routing information, "
143 			    "required buffer space of %d entries exceeds max\n",
144 			    nneeded);
145 			return;
146 		}
147 		n = nneeded;
148 		routes = kmem_zalloc(n * sizeof (pci_irq_route_t), KM_SLEEP);
149 		nroutes = pci_bios_get_irq_routing(routes, n, NULL);
150 		if (nroutes == 0) {
151 			cmn_err(CE_CONT,
152 			    "pci: unable to get IRQ routing information, "
153 			    "required buffer space for %d entries\n", n);
154 			kmem_free(routes, n * sizeof (pci_irq_route_t));
155 		}
156 	}
157 
158 	if (nroutes > 0) {
159 		pci_irq_routes = routes;
160 		pci_irq_nroutes = nroutes;
161 	}
162 }
163 
164 /*
165  * Use the results of the PCI BIOS call that returned the routing tables
166  * to build the 1275 slot-names property for the indicated bus.
167  * Results are returned in buf.  Length is return value, -1 is returned on
168  * overflow and zero is returned if no data exists to build a property.
169  */
170 int
171 pci_slot_names_prop(int bus, char *buf, int len)
172 {
173 	uchar_t		dev;
174 	uchar_t		slot[N_PCI_IRQ_ROUTES_MAX+1];
175 	uint32_t	 mask;
176 	int		i, nnames, plen;
177 
178 	ASSERT(pci_irq_nroutes <= N_PCI_IRQ_ROUTES_MAX);
179 
180 	if (pci_irq_nroutes == 0)
181 		return (0);
182 	nnames = 0;
183 	mask = 0;
184 	for (i = 0; i < pci_irq_nroutes; i++)
185 		slot[i] = 0xff;
186 	for (i = 0; i < pci_irq_nroutes; i++) {
187 		if (pci_irq_routes[i].pir_bus != bus)
188 			continue;
189 		if (pci_irq_routes[i].pir_slot != 0) {
190 			dev = (pci_irq_routes[i].pir_dev & 0xf8) >> 3;
191 			slot[dev] = pci_irq_routes[i].pir_slot;
192 			mask |= (1 << dev);
193 			nnames++;
194 		}
195 	}
196 
197 	if (nnames == 0)
198 		return (0);
199 
200 	if (len < (4 + nnames * 8))
201 		return (-1);
202 	*(uint32_t *)buf = mask;
203 	plen = 4;
204 	for (i = 0; i < pci_irq_nroutes; i++) {
205 		if (slot[i] == 0xff)
206 			continue;
207 		(void) sprintf(buf + plen, "Slot%d", slot[i]);
208 		plen += strlen(buf+plen) + 1;
209 		*(buf + plen) = 0;
210 	}
211 	for (; plen % 4; plen++)
212 		*(buf + plen) = 0;
213 	return (plen);
214 }
215