xref: /freebsd/sys/powerpc/booke/platform_bare.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/bus.h>
34 #include <sys/pcpu.h>
35 #include <sys/proc.h>
36 #include <sys/smp.h>
37 
38 #include <dev/ofw/openfirm.h>
39 
40 #include <machine/platform.h>
41 #include <machine/platformvar.h>
42 
43 #include "platform_if.h"
44 
45 extern uint32_t *bootinfo;
46 
47 static int bare_probe(platform_t);
48 static void bare_mem_regions(platform_t, struct mem_region *phys, int *physsz,
49     struct mem_region *avail, int *availsz);
50 static u_long bare_timebase_freq(platform_t, struct cpuref *cpuref);
51 
52 static void bare_reset(platform_t);
53 
54 static platform_method_t bare_methods[] = {
55 	PLATFORMMETHOD(platform_probe,		bare_probe),
56 	PLATFORMMETHOD(platform_mem_regions,	bare_mem_regions),
57 	PLATFORMMETHOD(platform_timebase_freq,	bare_timebase_freq),
58 
59 	PLATFORMMETHOD(platform_reset,		bare_reset),
60 
61 	PLATFORMMETHOD_END
62 };
63 
64 static platform_def_t bare_platform = {
65 	"bare",
66 	bare_methods,
67 	0
68 };
69 
70 PLATFORM_DEF(bare_platform);
71 
72 static int
73 bare_probe(platform_t plat)
74 {
75 
76 	if (OF_peer(0) == -1) /* Needs device tree to work */
77 		return (ENXIO);
78 
79 	return (BUS_PROBE_GENERIC);
80 }
81 
82 void
83 bare_mem_regions(platform_t plat, struct mem_region *phys, int *physsz,
84     struct mem_region *avail, int *availsz)
85 {
86 
87 	ofw_mem_regions(phys, physsz, avail, availsz);
88 }
89 
90 static u_long
91 bare_timebase_freq(platform_t plat, struct cpuref *cpuref)
92 {
93 	u_long ticks;
94 	phandle_t cpus, child;
95 	pcell_t freq;
96 
97 	if (bootinfo != NULL) {
98 		if (bootinfo[0] == 1) {
99 			/* Backward compatibility. See 8-STABLE. */
100 			ticks = bootinfo[3] >> 3;
101 		} else {
102 			/* Compatibility with Juniper's loader. */
103 			ticks = bootinfo[5] >> 3;
104 		}
105 	} else
106 		ticks = 0;
107 
108 	if ((cpus = OF_finddevice("/cpus")) == -1)
109 		goto out;
110 
111 	if ((child = OF_child(cpus)) == 0)
112 		goto out;
113 
114 	switch (OF_getproplen(child, "timebase-frequency")) {
115 	case 4:
116 	{
117 		uint32_t tbase;
118 		OF_getprop(child, "timebase-frequency", &tbase, sizeof(tbase));
119 		ticks = tbase;
120 		return (ticks);
121 	}
122 	case 8:
123 	{
124 		uint64_t tbase;
125 		OF_getprop(child, "timebase-frequency", &tbase, sizeof(tbase));
126 		ticks = tbase;
127 		return (ticks);
128 	}
129 	default:
130 		break;
131 	}
132 
133 	freq = 0;
134 	if (OF_getprop(child, "bus-frequency", (void *)&freq,
135 	    sizeof(freq)) <= 0)
136 		goto out;
137 
138 	/*
139 	 * Time Base and Decrementer are updated every 8 CCB bus clocks.
140 	 * HID0[SEL_TBCLK] = 0
141 	 */
142 	if (freq != 0)
143 		ticks = freq / 8;
144 
145 out:
146 	if (ticks <= 0)
147 		panic("Unable to determine timebase frequency!");
148 
149 	return (ticks);
150 }
151 
152 static void
153 bare_reset(platform_t plat)
154 {
155 
156 	printf("Reset failed...\n");
157 	while (1)
158 		;
159 }
160