ralink_wdog.c revision 1.1.2.1
1 /* $NetBSD: ralink_wdog.c,v 1.1.2.1 2011/07/01 05:45:45 matt Exp $ */ 2 /*- 3 * Copyright (c) 2011 CradlePoint Technology, Inc. 4 * All rights reserved. 5 * 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY CRADLEPOINT TECHNOLOGY, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * ra_wdog.c -- Ralink 305x Watchdog Timer driver 31 * 32 * Timer 1 is used as a system reset watchdog timer 33 * Timer 0 is (optionally) used as a periodic watchdog service interrupt 34 * 35 * NetBSD sysmon watchdog is used in mode defined by RA_WDOG_DEFAULT_MODE 36 * (which can be set via kernel config), or by mode passed to 37 * our 'smw_setmode' function. The mode used determines what 38 * mechanism is used to periodically service the watchdog. 39 * 40 * KTICKLE mode is default and supports 2 variants, allowing some control 41 * over the priority of the service routine: 42 * 43 * 1. the specified reset period is a positive integer: 44 * A callout runs the 'smw_tickle' function at IPL_SOFTCLOCK for service. 45 * If your system cannot make "forward progress" without softints running, 46 * you should use this variant. 47 * 48 * 2. the specified reset period is a negative integer: 49 * Timer 0 interrupt runs ra_wdog_timer0() at IPL_VM for service. 50 * If your system can make "forward progress" while spelding long times 51 * at IPL_VM, you should use this variant. 52 * The numbner is rectified 53 * 54 * The reset period is defined by RA_WDOG_DEFAULT_PERIOD 55 * (which can be set via kernel config), or by period passed to 56 * our 'smw_setmode' function. The interrupt service interval 57 * is half the reset interval. 58 * 59 */ 60 61 #include "rwdog.h" 62 63 #include <sys/cdefs.h> 64 __KERNEL_RCSID(0, "$NetBSD: ralink_wdog.c,v 1.1.2.1 2011/07/01 05:45:45 matt Exp $"); 65 66 #include <sys/param.h> 67 #include <sys/systm.h> 68 #include <sys/device.h> 69 #include <sys/wdog.h> 70 71 #include <machine/bus.h> 72 73 #include <mips/ralink/ralink_var.h> 74 #include <mips/ralink/ralink_reg.h> 75 76 #include <dev/sysmon/sysmonvar.h> 77 78 #if 0 79 # define DISABLE_WATCHDOG 80 #endif 81 82 #ifndef RA_WDOG_DEFAULT_MODE 83 # define RA_WDOG_DEFAULT_MODE WDOG_MODE_KTICKLE 84 #endif 85 86 /* 87 * PERIODs are in in seconds; 88 * the counter is 16-bits; 89 * maximum period depends on bus freq 90 */ 91 #ifndef RA_WDOG_DEFAULT_PERIOD 92 # define RA_WDOG_DEFAULT_PERIOD 10 93 #endif 94 #define WDOG_COUNT_MASK 0xffff 95 #define WDOG_MAX_COUNT WDOG_COUNT_MASK 96 #define WDOG_MAX_PERIOD \ 97 (WDOG_MAX_COUNT / (RA_BUS_FREQ / WDOG_MAX_COUNT)) 98 99 static int ra_wdog_match(device_t, cfdata_t, void *); 100 static void ra_wdog_attach(device_t, device_t, void *); 101 static int ra_wdog_tickle(struct sysmon_wdog *); 102 static int ra_wdog_timer0(void *); 103 static int ra_wdog_setmode(struct sysmon_wdog *); 104 105 extern int sysmon_wdog_setmode(struct sysmon_wdog *, int, u_int); 106 107 typedef struct ra_wdog_softc { 108 device_t sc_dev; 109 struct sysmon_wdog sc_smw; 110 bus_space_tag_t sc_memt; 111 bus_space_handle_t sc_memh; 112 void *sc_ih; 113 } ra_wdog_softc_t; 114 115 116 CFATTACH_DECL_NEW(rwdog, sizeof(struct ra_wdog_softc), 117 ra_wdog_match, ra_wdog_attach, NULL, NULL); 118 119 static const char *wdog_modestr[WDOG_MODE_MASK+1] = { 120 [ WDOG_MODE_DISARMED ] = "DISARMED", 121 [ WDOG_MODE_KTICKLE ] = "KTICKLE", 122 [ WDOG_MODE_UTICKLE ] = "UTICKLE", 123 [ WDOG_MODE_ETICKLE ] = "ETICKLE" 124 }; 125 126 static inline void 127 ra_wdog_reset(const ra_wdog_softc_t *sc) 128 { 129 uint32_t r; 130 131 r = bus_space_read_4(sc->sc_memt, sc->sc_memh, RA_TIMER_STAT); 132 r |= TIMER_1_RESET; 133 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_STAT, r); 134 } 135 136 static inline u_int32_t 137 ra_wdog_sec_to_count(u_int nsec) 138 { 139 KASSERT(nsec <= WDOG_MAX_PERIOD); 140 const u_int32_t count = (RA_BUS_FREQ / WDOG_MAX_COUNT) * nsec; 141 KASSERT(count <= WDOG_MAX_COUNT); 142 return count; 143 } 144 145 static int 146 ra_wdog_match(device_t parent, cfdata_t cf, void *aux) 147 { 148 return 1; 149 } 150 151 static void 152 ra_wdog_attach(device_t parent, device_t self, void *aux) 153 { 154 ra_wdog_softc_t * const sc = device_private(self); 155 const struct mainbus_attach_args *ma = aux; 156 bus_space_handle_t memh; 157 int error; 158 159 aprint_naive(": Ralink watchdog controller\n"); 160 aprint_normal(": Ralink watchdog controller\n"); 161 aprint_normal_dev(self, "max period %d sec.\n", WDOG_MAX_PERIOD); 162 163 error = bus_space_map(ma->ma_memt, RA_TIMER_BASE, 0x100, 0, &memh); 164 if (error != 0) { 165 aprint_error_dev(self, "unable to map registers, " 166 "error=%d\n", error); 167 return; 168 } 169 170 sc->sc_memt = ma->ma_memt; 171 sc->sc_memh = memh; 172 173 sc->sc_smw.smw_name = device_xname(self); 174 sc->sc_smw.smw_cookie = sc; 175 sc->sc_smw.smw_setmode = ra_wdog_setmode; 176 sc->sc_smw.smw_tickle = ra_wdog_tickle; 177 sc->sc_smw.smw_period = RA_WDOG_DEFAULT_PERIOD; 178 179 error = sysmon_wdog_register(&sc->sc_smw); 180 if (error != 0) 181 aprint_error_dev(self, "unable to register with sysmon, " 182 "error %d\n", error); 183 184 sc->sc_ih = ra_intr_establish(RA_IRQ_TIMER0, ra_wdog_timer0, sc, 0); 185 if (sc->sc_ih == NULL) 186 aprint_error_dev(self, "unable to establish interrupt\n"); 187 /* expect watchdog reset shortly */ 188 189 if (RA_WDOG_DEFAULT_MODE == WDOG_MODE_DISARMED) { 190 /* 191 * disarm the watchdog 192 */ 193 bus_space_write_4(sc->sc_memt, memh, RA_TIMER_0_CNTRL, 0); 194 bus_space_write_4(sc->sc_memt, memh, RA_TIMER_1_CNTRL, 0); 195 aprint_normal_dev(self, "%s mode\n", 196 wdog_modestr[sc->sc_smw.smw_mode]); 197 } else { 198 /* 199 * initialize and arm the watchdog now. 200 * if boot loader already initialized the watchdog 201 * then we are re-initializing; this will buy some time 202 * until interrupts are enabled, and will establish our 203 * (default) mode and smw_period indedpendent of the 204 * boot loader. 205 */ 206 error = sysmon_wdog_setmode(&sc->sc_smw, RA_WDOG_DEFAULT_MODE, 207 RA_WDOG_DEFAULT_PERIOD); 208 if (error != 0) { 209 aprint_error_dev(self, "unable to set sysmon wdog, " 210 "mode %d, error %d\n", 211 RA_WDOG_DEFAULT_MODE, error); 212 } else { 213 aprint_normal_dev(self, "%s mode, period %d sec.\n", 214 wdog_modestr[sc->sc_smw.smw_mode], 215 sc->sc_smw.smw_period); 216 } 217 } 218 } 219 220 /* 221 * ra_wdog_tickle - smw watchdog service function 222 */ 223 static int 224 ra_wdog_tickle(struct sysmon_wdog *smw) 225 { 226 const ra_wdog_softc_t * const sc = smw->smw_cookie; 227 ra_wdog_reset(sc); 228 return 0; 229 } 230 231 /* 232 * ra_wdog_timer0 - periodic watchdog service ISR 233 */ 234 static int 235 ra_wdog_timer0(void *arg) 236 { 237 const ra_wdog_softc_t * const sc = arg; 238 ra_wdog_reset(sc); 239 return 0; 240 } 241 242 static int 243 ra_wdog_setmode(struct sysmon_wdog *smw) 244 { 245 const ra_wdog_softc_t * const sc = smw->smw_cookie; 246 u_int period = smw->smw_period; 247 bool itickle = false; 248 uint32_t r; 249 250 if (((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_KTICKLE) && 251 ((int)period < 0)) { 252 itickle = true; /* use Timer 0 */ 253 period = -period; 254 } 255 256 /* all configuration has to be done with the timer disabled */ 257 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_0_CNTRL, 0); 258 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_1_CNTRL, 0); 259 260 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) 261 return 0; 262 263 if (period > WDOG_MAX_PERIOD) 264 return EOPNOTSUPP; 265 266 /* Set the new watchdog reset period in Timer 1 */ 267 r = ra_wdog_sec_to_count(period); 268 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_1_LOAD, r); 269 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_1_CNTRL, 270 TIMER_EN | TIMER_MODE(TIMER_MODE_WDOG) | 271 TIMER_PRESCALE(TIMER_PRESCALE_DIV_65536)); 272 273 if (itickle) { 274 /* Set the new watchdog service period in Timer 0 */ 275 r = ra_wdog_sec_to_count(period) / 2; 276 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_0_LOAD, r); 277 bus_space_write_4(sc->sc_memt, sc->sc_memh, RA_TIMER_0_CNTRL, 278 TIMER_EN | TIMER_MODE(TIMER_MODE_PERIODIC) | 279 TIMER_PRESCALE(TIMER_PRESCALE_DIV_65536)); 280 } 281 282 return 0; 283 } 284
Indexes created Wed Oct 15 16:09:53 GMT 2025