xref: /freebsd/sys/dev/virtio/mmio/virtio_mmio_cmdline.c (revision 942815c54820783d3d4f7f6faa71ab7919b5f0e5)
1 /*-
2  * Copyright (c) 2022 Colin Percival
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/bus.h>
29 #include <sys/kernel.h>
30 #include <sys/limits.h>
31 #include <sys/malloc.h>
32 #include <sys/module.h>
33 #include <sys/rman.h>
34 
35 #include <machine/bus.h>
36 #include <machine/resource.h>
37 
38 #include <dev/virtio/mmio/virtio_mmio.h>
39 
40 /* Parse <size>@<baseaddr>:<irq>[:<id>] and add a child. */
41 static void
42 parsearg(driver_t *driver, device_t parent, char * arg)
43 {
44 	device_t child;
45 	char * p;
46 	unsigned long sz;
47 	unsigned long baseaddr;
48 	unsigned long irq;
49 	unsigned long id;
50 
51 	/* <size> */
52 	sz = strtoul(arg, &p, 0);
53 	if ((sz == 0) || (sz == ULONG_MAX))
54 		goto bad;
55 	switch (*p) {
56 	case 'E': case 'e':
57 		sz <<= 10;
58 		/* FALLTHROUGH */
59 	case 'P': case 'p':
60 		sz <<= 10;
61 		/* FALLTHROUGH */
62 	case 'T': case 't':
63 		sz <<= 10;
64 		/* FALLTHROUGH */
65 	case 'G': case 'g':
66 		sz <<= 10;
67 		/* FALLTHROUGH */
68 	case 'M': case 'm':
69 		sz <<= 10;
70 		/* FALLTHROUGH */
71 	case 'K': case 'k':
72 		sz <<= 10;
73 		p++;
74 		break;
75 	}
76 
77 	/* @<baseaddr> */
78 	if (*p++ != '@')
79 		goto bad;
80 	baseaddr = strtoul(p, &p, 0);
81 	if ((baseaddr == 0) || (baseaddr == ULONG_MAX))
82 		goto bad;
83 
84 	/* :<irq> */
85 	if (*p++ != ':')
86 		goto bad;
87 	irq = strtoul(p, &p, 0);
88 	if ((irq == 0) || (irq == ULONG_MAX))
89 		goto bad;
90 
91 	/* Optionally, :<id> */
92 	if (*p) {
93 		if (*p++ != ':')
94 			goto bad;
95 		id = strtoul(p, &p, 0);
96 		if ((id == 0) || (id == ULONG_MAX))
97 			goto bad;
98 	} else {
99 		id = 0;
100 	}
101 
102 	/* Should have reached the end of the string. */
103 	if (*p)
104 		goto bad;
105 
106 	/* Create the child and assign its resources. */
107 	child = BUS_ADD_CHILD(parent, 0, driver->name, id ? id : -1);
108 	bus_set_resource(child, SYS_RES_MEMORY, 0, baseaddr, sz);
109 	bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1);
110 	device_set_driver(child, driver);
111 
112 	return;
113 
114 bad:
115 	printf("Error parsing virtio_mmio parameter: %s\n", arg);
116 }
117 
118 static void
119 vtmmio_cmdline_identify(driver_t *driver, device_t parent)
120 {
121 	size_t n;
122 	char name[] = "virtio_mmio.device_XXXX";
123 	char * val;
124 
125 	/* First variable just has its own name. */
126 	if ((val = kern_getenv("virtio_mmio.device")) == NULL)
127 		return;
128 	parsearg(driver, parent, val);
129 	freeenv(val);
130 
131 	/* The rest have _%zu suffixes. */
132 	for (n = 1; n <= 9999; n++) {
133 		sprintf(name, "virtio_mmio.device_%zu", n);
134 		if ((val = kern_getenv(name)) == NULL)
135 			return;
136 		parsearg(driver, parent, val);
137 		freeenv(val);
138 	}
139 }
140 
141 static device_method_t vtmmio_cmdline_methods[] = {
142         /* Device interface. */
143 	DEVMETHOD(device_identify,	vtmmio_cmdline_identify),
144 	DEVMETHOD(device_probe,		vtmmio_probe),
145 
146         DEVMETHOD_END
147 };
148 DEFINE_CLASS_1(virtio_mmio, vtmmio_cmdline_driver, vtmmio_cmdline_methods,
149     sizeof(struct vtmmio_softc), vtmmio_driver);
150 DRIVER_MODULE(vtmmio_cmdline, nexus, vtmmio_cmdline_driver, 0, 0);
151