1 /* $NetBSD: e500wdog.c,v 1.4 2020/07/06 09:34:16 rin Exp $ */
2 /*-
3 * Copyright (c) 2010, 2011 The NetBSD Foundation, Inc.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to The NetBSD Foundation
7 * by Raytheon BBN Technologies Corp and Defense Advanced Research Projects
8 * Agency and which was developed by Matt Thomas of 3am Software Foundry.
9 *
10 * This material is based upon work supported by the Defense Advanced Research
11 * Projects Agency and Space and Naval Warfare Systems Center, Pacific, under
12 * Contract No. N66001-09-C-2073.
13 * Approved for Public Release, Distribution Unlimited
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
28 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: e500wdog.c,v 1.4 2020/07/06 09:34:16 rin Exp $");
39
40 #include "ioconf.h"
41
42 #include <sys/param.h>
43 #include <sys/cpu.h>
44 #include <sys/device.h>
45 #include <sys/wdog.h>
46
47 #include <dev/sysmon/sysmonvar.h>
48
49 #include <sys/intr.h>
50
51 #include <powerpc/spr.h>
52 #include <powerpc/booke/spr.h>
53
54 #include <powerpc/booke/cpuvar.h>
55
56 struct e500wdog_softc {
57 device_t sc_dev;
58 struct sysmon_wdog sc_smw;
59 u_int sc_wdog_period;
60 bool sc_wdog_armed;
61 uint64_t sc_timebase;
62 };
63 #ifndef PQ3WDOG_PERIOD_DEFAULT
64 #define PQ3WDOG_PERIOD_DEFAULT 10
65 #endif
66
67 static int e500wdog_match(device_t, cfdata_t, void *);
68 static void e500wdog_attach(device_t, device_t, void *);
69
70 CFATTACH_DECL_NEW(e500wdog, sizeof(struct e500wdog_softc),
71 e500wdog_match, e500wdog_attach, NULL, NULL);
72
73 static int
e500wdog_match(device_t parent,cfdata_t cf,void * aux)74 e500wdog_match(device_t parent, cfdata_t cf, void *aux)
75 {
76 struct cpunode_softc * const psc = device_private(parent);
77 struct cpunode_attach_args * const cna = aux;
78 struct cpunode_locators * const cnl = &cna->cna_locs;
79
80 if (!board_info_get_bool("pq3")
81 || cnl->cnl_instance != 0
82 || (psc->sc_children & cna->cna_childmask)
83 || strcmp(cnl->cnl_name, "wdog") != 0)
84 return 0;
85
86 return 1;
87 }
88
89 static int
e500wdog_tickle(struct sysmon_wdog * smw)90 e500wdog_tickle(struct sysmon_wdog *smw)
91 {
92 mtspr(SPR_TSR, TSR_ENW);
93 return 0;
94 }
95
96 static int
e500wdog_setmode(struct sysmon_wdog * smw)97 e500wdog_setmode(struct sysmon_wdog *smw)
98 {
99 struct e500wdog_softc * const sc = smw->smw_cookie;
100
101 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
102 /*
103 * We can't disarm the watchdog.
104 */
105 if (sc->sc_wdog_armed)
106 return EBUSY;
107 } else {
108 /*
109 * If no changes, don't do anything.
110 */
111 if (sc->sc_wdog_armed
112 && smw->smw_period == sc->sc_wdog_period) {
113 mtspr(SPR_TSR, TSR_ENW);
114 return 0;
115 }
116 printf("%s:%d %u %u\n", __func__, __LINE__,
117 sc->sc_wdog_period, smw->smw_period);
118 if (smw->smw_period == WDOG_PERIOD_DEFAULT) {
119 sc->sc_wdog_period = PQ3WDOG_PERIOD_DEFAULT;
120 smw->smw_period = PQ3WDOG_PERIOD_DEFAULT;
121 }
122 mtspr(SPR_TSR, TSR_ENW);
123 uint32_t tcr = mfspr(SPR_TCR);
124 if (!sc->sc_wdog_armed)
125 tcr = (tcr & ~TCR_WRC) | TCR_WRC_RESET | TCR_WIE;
126 const uint64_t period = sc->sc_wdog_period * sc->sc_timebase / 3;
127 const u_int wp = __builtin_clz(period) + 1;
128 tcr &= ~(TCR_WP|TCR_WPEXT);
129 tcr |= __SHIFTIN(wp, TCR_WP) | __SHIFTIN(wp >> 2, TCR_WPEXT);
130 mtspr(SPR_TCR, tcr);
131 sc->sc_wdog_period =
132 ((1ULL << (63 - wp)) + sc->sc_timebase - 1)
133 / sc->sc_timebase;
134 sc->sc_wdog_armed = true;
135 }
136 return 0;
137 }
138
139 static void
e500wdog_attach(device_t parent,device_t self,void * aux)140 e500wdog_attach(device_t parent, device_t self, void *aux)
141 {
142 struct cpunode_softc * const psc = device_private(parent);
143 struct e500wdog_softc * const sc = device_private(self);
144 struct cpunode_attach_args * const cna = aux;
145
146 psc->sc_children |= cna->cna_childmask;
147 sc->sc_dev = self;
148
149 sc->sc_timebase = board_info_get_number("timebase-frequency");
150 const uint32_t tcr = mfspr(SPR_TCR);
151 u_int wp = __SHIFTOUT(tcr, TCR_WP) | (__SHIFTOUT(tcr, TCR_WPEXT) << 2);
152
153 #if DEBUG > 1
154 printf(" tcr=%#x wp=%u", tcr, wp);
155 printf(" timebase=%"PRIu64, sc->sc_timebase);
156 #endif
157 sc->sc_wdog_armed = (tcr & TCR_WRC) != 0;
158 if (sc->sc_wdog_armed)
159 sc->sc_wdog_period = ((1ULL << (63 - wp)) + sc->sc_timebase - 1)
160 / sc->sc_timebase;
161 else
162 sc->sc_wdog_period = PQ3WDOG_PERIOD_DEFAULT;
163
164 aprint_normal(": default period is %u seconds%s\n",
165 sc->sc_wdog_period,
166 sc->sc_wdog_armed ? " (wdog is active)" : "");
167
168 sc->sc_smw.smw_name = device_xname(sc->sc_dev);
169 sc->sc_smw.smw_cookie = sc;
170 sc->sc_smw.smw_setmode = e500wdog_setmode;
171 sc->sc_smw.smw_tickle = e500wdog_tickle;
172 sc->sc_smw.smw_period = sc->sc_wdog_period;
173
174 if (sysmon_wdog_register(&sc->sc_smw) != 0)
175 aprint_error_dev(self, "unable to register with sysmon\n");
176
177 #if 1
178 if (sc->sc_wdog_armed) {
179 int error = sysmon_wdog_setmode(&sc->sc_smw, WDOG_MODE_KTICKLE,
180 sc->sc_wdog_period);
181 if (error)
182 aprint_error_dev(self,
183 "failed to start kernel tickler: %d\n", error);
184 }
185 #else
186 //mtspr(SPR_TSR, TSR_ENW);
187 #endif
188 }
189