xref: /netbsd-src/sys/dev/ofw/ofw_pci_subr.c (revision 3944ff70a48a86bb622139705a33f8ef461e24f7)
1 /*	$NetBSD: ofw_pci_subr.c,v 1.3 2022/01/22 11:49:18 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2021 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: ofw_pci_subr.c,v 1.3 2022/01/22 11:49:18 thorpej Exp $");
34 
35 #include <sys/types.h>
36 #include <sys/device.h>
37 #include <sys/endian.h>
38 #include <sys/errno.h>
39 
40 #include <dev/pci/pcivar.h>
41 #include <dev/pci/pci_calls.h>
42 
43 #include <dev/ofw/openfirm.h>
44 #include <dev/ofw/ofw_pci.h>
45 
46 static int
ofw_pci_bus_get_child_devhandle(device_t dev,devhandle_t call_handle,void * v)47 ofw_pci_bus_get_child_devhandle(device_t dev, devhandle_t call_handle, void *v)
48 {
49 	struct pci_bus_get_child_devhandle_args *args = v;
50 	int phandle = devhandle_to_of(call_handle);
51 	struct ofw_pci_register opr;
52 	int d, f, len;
53 	uint32_t phys_hi;
54 
55 	/*
56 	 * No need to compare the bus number; we are searching
57 	 * only direct children of the specified node.  Skipping
58 	 * the bus number comparison allows us to dodge a slight
59 	 * difference between the OpenFirmware and FDT PCI bindings
60 	 * as it relates to PCI-PCI bridges.
61 	 */
62 
63 	pci_decompose_tag(args->pc, args->tag, NULL, &d, &f);
64 
65 	for (phandle = OF_child(phandle); phandle != 0;
66 	     phandle = OF_peer(phandle)) {
67 		len = OF_getprop(phandle, "reg", &opr, sizeof(opr));
68 		if (len < sizeof(opr)) {
69 			continue;
70 		}
71 
72 		phys_hi = be32toh(opr.phys_hi);
73 
74 		if (d != OFW_PCI_PHYS_HI_DEVICE(phys_hi) ||
75 		    f != OFW_PCI_PHYS_HI_FUNCTION(phys_hi)) {
76 			continue;
77 		}
78 
79 		/* Found it! */
80 		args->devhandle = devhandle_from_of(call_handle, phandle);
81 		return 0;
82 	}
83 
84 	return ENODEV;
85 }
86 OF_DEVICE_CALL_REGISTER(PCI_BUS_GET_CHILD_DEVHANDLE_STR,
87 			ofw_pci_bus_get_child_devhandle)
88