xref: /freebsd/sys/powerpc/booke/platform_bare.c (revision db33c6f3ae9d1231087710068ee4ea5398aacca7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008-2012 Semihalf.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
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  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/bus.h>
33 #include <sys/pcpu.h>
34 #include <sys/proc.h>
35 #include <sys/smp.h>
36 
37 #include <dev/ofw/openfirm.h>
38 
39 #include <machine/platform.h>
40 #include <machine/platformvar.h>
41 
42 #include "platform_if.h"
43 
44 extern uint32_t *bootinfo;
45 
46 static int bare_probe(platform_t);
47 static void bare_mem_regions(platform_t, struct mem_region *phys, int *physsz,
48     struct mem_region *avail, int *availsz);
49 static u_long bare_timebase_freq(platform_t, struct cpuref *cpuref);
50 
51 static void bare_reset(platform_t);
52 
53 static platform_method_t bare_methods[] = {
54 	PLATFORMMETHOD(platform_probe,		bare_probe),
55 	PLATFORMMETHOD(platform_mem_regions,	bare_mem_regions),
56 	PLATFORMMETHOD(platform_timebase_freq,	bare_timebase_freq),
57 
58 	PLATFORMMETHOD(platform_reset,		bare_reset),
59 
60 	PLATFORMMETHOD_END
61 };
62 
63 static platform_def_t bare_platform = {
64 	"bare",
65 	bare_methods,
66 	0
67 };
68 
69 PLATFORM_DEF(bare_platform);
70 
71 static int
72 bare_probe(platform_t plat)
73 {
74 
75 	if (OF_peer(0) == -1) /* Needs device tree to work */
76 		return (ENXIO);
77 
78 	return (BUS_PROBE_GENERIC);
79 }
80 
81 void
82 bare_mem_regions(platform_t plat, struct mem_region *phys, int *physsz,
83     struct mem_region *avail, int *availsz)
84 {
85 
86 	ofw_mem_regions(phys, physsz, avail, availsz);
87 }
88 
89 static u_long
90 bare_timebase_freq(platform_t plat, struct cpuref *cpuref)
91 {
92 	u_long ticks;
93 	phandle_t cpus, child;
94 	pcell_t freq;
95 
96 	if (bootinfo != NULL) {
97 		if (bootinfo[0] == 1) {
98 			/* Backward compatibility. See 8-STABLE. */
99 			ticks = bootinfo[3] >> 3;
100 		} else {
101 			/* Compatibility with Juniper's loader. */
102 			ticks = bootinfo[5] >> 3;
103 		}
104 	} else
105 		ticks = 0;
106 
107 	if ((cpus = OF_finddevice("/cpus")) == -1)
108 		goto out;
109 
110 	if ((child = OF_child(cpus)) == 0)
111 		goto out;
112 
113 	switch (OF_getproplen(child, "timebase-frequency")) {
114 	case 4:
115 	{
116 		uint32_t tbase;
117 		OF_getprop(child, "timebase-frequency", &tbase, sizeof(tbase));
118 		ticks = tbase;
119 		return (ticks);
120 	}
121 	case 8:
122 	{
123 		uint64_t tbase;
124 		OF_getprop(child, "timebase-frequency", &tbase, sizeof(tbase));
125 		ticks = tbase;
126 		return (ticks);
127 	}
128 	default:
129 		break;
130 	}
131 
132 	freq = 0;
133 	if (OF_getprop(child, "bus-frequency", (void *)&freq,
134 	    sizeof(freq)) <= 0)
135 		goto out;
136 
137 	/*
138 	 * Time Base and Decrementer are updated every 8 CCB bus clocks.
139 	 * HID0[SEL_TBCLK] = 0
140 	 */
141 	if (freq != 0)
142 		ticks = freq / 8;
143 
144 out:
145 	if (ticks <= 0)
146 		panic("Unable to determine timebase frequency!");
147 
148 	return (ticks);
149 }
150 
151 static void
152 bare_reset(platform_t plat)
153 {
154 
155 	printf("Reset failed...\n");
156 	while (1)
157 		;
158 }
159