xref: /netbsd-src/sys/arch/alpha/pci/irongate_pci.c (revision 8749255d22ee5aef6bc71797c2b99c427754987d)
1 /* $NetBSD: irongate_pci.c,v 1.13 2024/04/03 04:30:30 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2000 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 /*
33  * PCI Configuration Space support for the AMD 751 (``Irongate'') core logic
34  * chipset.
35  */
36 
37 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
38 
39 __KERNEL_RCSID(0, "$NetBSD: irongate_pci.c,v 1.13 2024/04/03 04:30:30 thorpej Exp $");
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/device.h>
45 
46 #include <dev/pci/pcireg.h>
47 #include <dev/pci/pcivar.h>
48 #include <alpha/pci/irongatereg.h>
49 #include <alpha/pci/irongatevar.h>
50 
51 static pcireg_t	irongate_conf_read(void *, pcitag_t, int);
52 static void	irongate_conf_write(void *, pcitag_t, int, pcireg_t);
53 
54 /* AMD 751 systems are always single-processor, so this is easy. */
55 #define	PCI_CONF_LOCK(s)	(s) = splhigh()
56 #define	PCI_CONF_UNLOCK(s)	splx((s))
57 
58 #define	PCI_CONF_ADDR	(IRONGATE_IO_BASE|IRONGATE_CONFADDR)
59 #define	PCI_CONF_DATA	(IRONGATE_IO_BASE|IRONGATE_CONFDATA)
60 
61 #define	REGVAL(r)	(*(volatile uint32_t *)ALPHA_PHYS_TO_K0SEG(r))
62 
63 void
irongate_pci_init(pci_chipset_tag_t pc,void * v)64 irongate_pci_init(pci_chipset_tag_t pc, void *v)
65 {
66 
67 	pc->pc_conf_v = v;
68 	pc->pc_conf_read = irongate_conf_read;
69 	pc->pc_conf_write = irongate_conf_write;
70 }
71 
72 static pcireg_t
irongate_conf_read(void * ipv,pcitag_t tag,int offset)73 irongate_conf_read(void *ipv, pcitag_t tag, int offset)
74 {
75 	int b, d;
76 
77 	if ((unsigned int)offset >= PCI_CONF_SIZE)
78 		return (pcireg_t) -1;
79 
80 	struct irongate_config * const icp = ipv;
81 
82 	/*
83 	 * The AMD 751 appears in PCI configuration space, but
84 	 * that is ... counter-intuitive to the way we normally
85 	 * attach PCI-Host bridges on the Alpha.  So, filter out
86 	 * the AMD 751 device here.  We provide a private entry
87 	 * point for getting at it from machdep code.
88 	 */
89 	pci_decompose_tag(&icp->ic_pc, tag, &b, &d, NULL);
90 	if (b == 0 && d == IRONGATE_PCIHOST_DEV && offset == PCI_ID_REG)
91 		return ((pcireg_t) -1);
92 
93 	return (irongate_conf_read0(ipv, tag, offset));
94 }
95 
96 pcireg_t
irongate_conf_read0(void * ipv,pcitag_t tag,int offset)97 irongate_conf_read0(void *ipv, pcitag_t tag, int offset)
98 {
99 	pcireg_t data;
100 	int s;
101 
102 	if ((unsigned int)offset >= PCI_CONF_SIZE)
103 		return (pcireg_t) -1;
104 
105 	PCI_CONF_LOCK(s);
106 	REGVAL(PCI_CONF_ADDR) = (CONFADDR_ENABLE | tag | (offset & 0xff));
107 	alpha_mb();
108 	data = REGVAL(PCI_CONF_DATA);
109 	alpha_mb();
110 	REGVAL(PCI_CONF_ADDR) = 0;
111 	alpha_mb();
112 	PCI_CONF_UNLOCK(s);
113 
114 	return (data);
115 }
116 
117 static void
irongate_conf_write(void * ipv,pcitag_t tag,int offset,pcireg_t data)118 irongate_conf_write(void *ipv, pcitag_t tag, int offset, pcireg_t data)
119 {
120 	int s;
121 
122 	if ((unsigned int)offset >= PCI_CONF_SIZE)
123 		return;
124 
125 	PCI_CONF_LOCK(s);
126 	REGVAL(PCI_CONF_ADDR) = (CONFADDR_ENABLE | tag | (offset & 0xff));
127 	alpha_mb();
128 	REGVAL(PCI_CONF_DATA) = data;
129 	alpha_mb();
130 	REGVAL(PCI_CONF_ADDR) = 0;
131 	alpha_mb();
132 	PCI_CONF_UNLOCK(s);
133 }
134