xref: /netbsd-src/sys/arch/dreamcast/dev/g2/gapspci_pci.c (revision 3c7a3199b61179961749a6b659cab2fe11746cc5)
1 /*	$NetBSD: gapspci_pci.c,v 1.18 2021/08/07 19:41:13 andvar Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 Marcus Comstedt.
5  * Copyright (c) 2001 Jason R. Thorpe.
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Marcus Comstedt.
19  * 4. Neither the name of The NetBSD Foundation nor the names of its
20  *    contributors may be used to endorse or promote products derived
21  *    from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /*
37  * PCI configuration space implementation for the SEGA GAPS PCI bridge.
38  */
39 
40 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
41 __KERNEL_RCSID(0, "$NetBSD: gapspci_pci.c,v 1.18 2021/08/07 19:41:13 andvar Exp $");
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/device.h>
47 #include <sys/bus.h>
48 
49 #include <machine/cpu.h>
50 #include <machine/sysasicvar.h>
51 
52 #include <dev/pci/pcivar.h>
53 #include <dev/pci/pcireg.h>
54 
55 #include <dreamcast/dev/g2/gapspcivar.h>
56 
57 void		gaps_attach_hook(device_t, device_t,
58 		    struct pcibus_attach_args *);
59 int		gaps_bus_maxdevs(void *, int);
60 pcitag_t	gaps_make_tag(void *, int, int, int);
61 void		gaps_decompose_tag(void *, pcitag_t, int *, int *, int *);
62 pcireg_t	gaps_conf_read(void *, pcitag_t, int);
63 void		gaps_conf_write(void *, pcitag_t, int, pcireg_t);
64 
65 int		gaps_intr_map(const struct pci_attach_args *, pci_intr_handle_t *);
66 const char	*gaps_intr_string(void *, pci_intr_handle_t,
67 		    char *buf, size_t len);
68 void		*gaps_intr_establish(void *, pci_intr_handle_t,
69 		    int, int (*)(void *), void *);
70 void		gaps_intr_disestablish(void *, void *);
71 
72 void
gaps_pci_init(struct gaps_softc * sc)73 gaps_pci_init(struct gaps_softc *sc)
74 {
75 	pci_chipset_tag_t pc = &sc->sc_pc;
76 
77 	memset(pc, 0, sizeof(*pc));
78 
79 	pc->pc_attach_hook = gaps_attach_hook;
80 	pc->pc_bus_maxdevs = gaps_bus_maxdevs;
81 	pc->pc_make_tag = gaps_make_tag;
82 	pc->pc_decompose_tag = gaps_decompose_tag;
83 	pc->pc_conf_read = gaps_conf_read;
84 	pc->pc_conf_write = gaps_conf_write;
85 	pc->pc_conf_v = sc;
86 
87 	pc->pc_intr_map = gaps_intr_map;
88 	pc->pc_intr_string = gaps_intr_string;
89 	pc->pc_intr_establish = gaps_intr_establish;
90 	pc->pc_intr_disestablish = gaps_intr_disestablish;
91 
92 	if (bus_space_map(sc->sc_memt, 0x01001600, 0x100,
93 	    0, &sc->sc_pci_memh) != 0)
94 		panic("gaps_pci_init: can't map PCI configuration space");
95 }
96 
97 #define	GAPS_PCITAG_MAGIC	0x022473
98 
99 void
gaps_attach_hook(device_t parent,device_t pci,struct pcibus_attach_args * pba)100 gaps_attach_hook(device_t parent, device_t pci, struct pcibus_attach_args *pba)
101 {
102 	struct gaps_softc *sc = device_private(parent);
103 
104 	/*
105 	 * Now that we know there's a bus configured, go ahead and
106 	 * program the BAR on the device.
107 	 */
108 	pci_conf_write(&sc->sc_pc, GAPS_PCITAG_MAGIC,
109 	    PCI_MAPREG_START + 4, 0x01000000);
110 	pci_conf_write(&sc->sc_pc, GAPS_PCITAG_MAGIC, PCI_COMMAND_STATUS_REG,
111 	    pci_conf_read(&sc->sc_pc, 0, PCI_COMMAND_STATUS_REG) |
112 	    PCI_COMMAND_MEM_ENABLE | PCI_COMMAND_MASTER_ENABLE);
113 }
114 
115 int
gaps_bus_maxdevs(void * v,int bus)116 gaps_bus_maxdevs(void *v, int bus)
117 {
118 
119 	return 1;
120 }
121 
122 pcitag_t
gaps_make_tag(void * v,int bus,int dev,int func)123 gaps_make_tag(void *v, int bus, int dev, int func)
124 {
125 
126 	if (bus == 0 && dev == 0 && func == 0)
127 		return GAPS_PCITAG_MAGIC;
128 
129 	return 0;
130 }
131 
132 void
gaps_decompose_tag(void * v,pcitag_t tag,int * bp,int * dp,int * fp)133 gaps_decompose_tag(void *v, pcitag_t tag, int *bp, int *dp, int *fp)
134 {
135 	int b, d, f;
136 
137 	if (tag == GAPS_PCITAG_MAGIC)
138 		b = d = f = 0;
139 	else {
140 		/*
141 		 * Invalid for GAPS.  These values ensure that a valid
142 		 * tag cannot be built.
143 		 */
144 		b = 0xff;
145 		d = 0x1f;
146 		f = 0x7;
147 	}
148 
149 	if (bp != NULL)
150 		*bp = b;
151 	if (dp != NULL)
152 		*dp = d;
153 	if (fp != NULL)
154 		*fp = f;
155 }
156 
157 pcireg_t
gaps_conf_read(void * v,pcitag_t tag,int reg)158 gaps_conf_read(void *v, pcitag_t tag, int reg)
159 {
160 	struct gaps_softc *sc = v;
161 
162 	if (tag != GAPS_PCITAG_MAGIC)
163 		return -1;
164 
165 	if ((unsigned int)reg >= PCI_CONF_SIZE)
166 		return -1;
167 
168 	if (reg == (PCI_MAPREG_START + 4)) {
169 		/*
170 		 * We fake the BAR -- just return the physical address
171 		 * to which the device is mapped.
172 		 */
173 		return 0x01001700;
174 	}
175 
176 	return bus_space_read_4(sc->sc_memt, sc->sc_pci_memh, reg);
177 }
178 
179 void
gaps_conf_write(void * v,pcitag_t tag,int reg,pcireg_t val)180 gaps_conf_write(void *v, pcitag_t tag, int reg, pcireg_t val)
181 {
182 	struct gaps_softc *sc = v;
183 
184 	if (tag != GAPS_PCITAG_MAGIC)
185 		return;
186 
187 	if ((unsigned int)reg >= PCI_CONF_SIZE)
188 		return;
189 
190 	/* Disallow writing to the "BAR" ... it doesn't actually exist. */
191 	if (reg == (PCI_MAPREG_START + 4) && val != 0x01000000)
192 		return;
193 
194 	bus_space_write_4(sc->sc_memt, sc->sc_pci_memh, reg, val);
195 }
196 
197 int
gaps_intr_map(const struct pci_attach_args * pa,pci_intr_handle_t * ihp)198 gaps_intr_map(const struct pci_attach_args *pa, pci_intr_handle_t *ihp)
199 {
200 
201 	*ihp = SYSASIC_EVENT_EXT;
202 	return 0;
203 }
204 
205 const char *
gaps_intr_string(void * v,pci_intr_handle_t ih,char * buf,size_t len)206 gaps_intr_string(void *v, pci_intr_handle_t ih,
207     char *buf, size_t len)
208 {
209 
210 	strlcpy(buf, sysasic_intr_string(SYSASIC_IRL11), len);
211 	return buf;
212 }
213 
214 void *
gaps_intr_establish(void * v,pci_intr_handle_t ih,int level,int (* func)(void *),void * arg)215 gaps_intr_establish(void *v, pci_intr_handle_t ih, int level,
216     int (*func)(void *), void *arg)
217 {
218 
219 	return sysasic_intr_establish(ih, level, SYSASIC_IRL11, func, arg);
220 }
221 
222 void
gaps_intr_disestablish(void * v,void * ih)223 gaps_intr_disestablish(void *v, void *ih)
224 {
225 
226 	return sysasic_intr_disestablish(ih);
227 }
228