1 /* $NetBSD: sunxi_wdt.c,v 1.6 2021/01/27 03:10:20 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
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 * 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 THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: sunxi_wdt.c,v 1.6 2021/01/27 03:10:20 thorpej Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/mutex.h>
38 #include <sys/wdog.h>
39
40 #include <dev/sysmon/sysmonvar.h>
41
42 #include <dev/fdt/fdtvar.h>
43
44 #define SUNXI_WDT_PERIOD_DEFAULT 16
45
46 #define SUN4I_WDT_CTRL_REG 0x00
47 #define SUN4I_WDT_CTRL_KEY_FIELD __BITS(12,1)
48 #define SUN4I_WDT_CTRL_KEY_FIELD_V 0xa57
49 #define SUN4I_WDT_CTRL_RSTART __BIT(0)
50 #define SUN4I_WDT_MODE_REG 0x04
51 #define SUN4I_WDT_MODE_INTV __BITS(6,3)
52 #define SUN4I_WDT_MODE_RST_EN __BIT(1)
53 #define SUN4I_WDT_MODE_EN __BIT(0)
54
55 #define SUN6I_WDT_IRQ_EN_REG 0x00
56 #define SUN6I_WDT_IRQ_EN_EN __BIT(0)
57 #define SUN6I_WDT_IRQ_STA_REG 0x04
58 #define SUN6I_WDT_IRQ_STA_PEND __BIT(0)
59 #define SUN6I_WDT_CTRL_REG 0x10
60 #define SUN6I_WDT_CTRL_KEY_FIELD __BITS(12,1)
61 #define SUN6I_WDT_CTRL_KEY_FIELD_V 0xa57
62 #define SUN6I_WDT_CTRL_RSTART __BIT(0)
63 #define SUN6I_WDT_CFG_REG 0x14
64 #define SUN6I_WDT_CFG_CONFIG __BITS(1,0)
65 #define SUN6I_WDT_CFG_CONFIG_SYS 1
66 #define SUN6I_WDT_CFG_CONFIG_IRQ 2
67 #define SUN6I_WDT_MODE_REG 0x18
68 #define SUN6I_WDT_MODE_INTV __BITS(7,4)
69 #define SUN6I_WDT_MODE_EN __BIT(0)
70
71 static const int sunxi_periods[] = {
72 500, 1000, 2000, 3000,
73 4000, 5000, 6000, 8000,
74 10000, 12000, 14000, 16000,
75 -1
76 };
77
78 enum sunxi_wdt_type {
79 WDT_SUN4I = 1,
80 WDT_SUN6I,
81 };
82
83 static const struct device_compatible_entry compat_data[] = {
84 { .compat = "allwinner,sun4i-a10-wdt", .value = WDT_SUN4I },
85 { .compat = "allwinner,sun6i-a31-wdt", .value = WDT_SUN6I },
86 DEVICE_COMPAT_EOL
87 };
88
89 struct sunxi_wdt_softc {
90 device_t sc_dev;
91 bus_space_tag_t sc_bst;
92 bus_space_handle_t sc_bsh;
93
94 const int *sc_periods;
95
96 struct sysmon_wdog sc_smw;
97 };
98
99 #define WDT_READ(sc, reg) \
100 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
101 #define WDT_WRITE(sc, reg, val) \
102 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
103
104 static int
sunxi_wdt_map_period(struct sunxi_wdt_softc * sc,u_int period,u_int * aperiod)105 sunxi_wdt_map_period(struct sunxi_wdt_softc *sc, u_int period,
106 u_int *aperiod)
107 {
108 const int *p = sc->sc_periods;
109 int i;
110
111 if (period == 0)
112 return -1;
113
114 for (i = 0; *p != -1; i++, p++)
115 if (*p >= period * 1000) {
116 *aperiod = *p / 1000;
117 return i;
118 }
119
120 return -1;
121 }
122
123 static int
sun4i_wdt_setmode(struct sysmon_wdog * smw)124 sun4i_wdt_setmode(struct sysmon_wdog *smw)
125 {
126 struct sunxi_wdt_softc * const sc = smw->smw_cookie;
127 uint32_t mode;
128 int intv;
129
130 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
131 WDT_WRITE(sc, SUN4I_WDT_MODE_REG, 0);
132 } else {
133 if (smw->smw_period == WDOG_PERIOD_DEFAULT)
134 smw->smw_period = SUNXI_WDT_PERIOD_DEFAULT;
135 intv = sunxi_wdt_map_period(sc, smw->smw_period,
136 &sc->sc_smw.smw_period);
137 if (intv == -1)
138 return EINVAL;
139
140 mode = SUN4I_WDT_MODE_EN | SUN4I_WDT_MODE_RST_EN |
141 __SHIFTIN(intv, SUN4I_WDT_MODE_INTV);
142
143 WDT_WRITE(sc, SUN4I_WDT_MODE_REG, mode);
144 }
145
146 return 0;
147 }
148
149 static int
sun4i_wdt_tickle(struct sysmon_wdog * smw)150 sun4i_wdt_tickle(struct sysmon_wdog *smw)
151 {
152 struct sunxi_wdt_softc * const sc = smw->smw_cookie;
153 const uint32_t ctrl = SUN4I_WDT_CTRL_RSTART |
154 __SHIFTIN(SUN4I_WDT_CTRL_KEY_FIELD_V, SUN4I_WDT_CTRL_KEY_FIELD);
155
156 WDT_WRITE(sc, SUN4I_WDT_CTRL_REG, ctrl);
157
158 return 0;
159 }
160
161 static int
sun6i_wdt_setmode(struct sysmon_wdog * smw)162 sun6i_wdt_setmode(struct sysmon_wdog *smw)
163 {
164 struct sunxi_wdt_softc * const sc = smw->smw_cookie;
165 uint32_t cfg, mode;
166 int intv;
167
168 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
169 WDT_WRITE(sc, SUN6I_WDT_MODE_REG, 0);
170 } else {
171 if (smw->smw_period == WDOG_PERIOD_DEFAULT)
172 smw->smw_period = SUNXI_WDT_PERIOD_DEFAULT;
173 intv = sunxi_wdt_map_period(sc, smw->smw_period,
174 &sc->sc_smw.smw_period);
175 if (intv == -1)
176 return EINVAL;
177
178 cfg = __SHIFTIN(SUN6I_WDT_CFG_CONFIG_SYS, SUN6I_WDT_CFG_CONFIG);
179 mode = SUN6I_WDT_MODE_EN | __SHIFTIN(intv, SUN6I_WDT_MODE_INTV);
180
181 WDT_WRITE(sc, SUN6I_WDT_CFG_REG, cfg);
182 WDT_WRITE(sc, SUN6I_WDT_MODE_REG, mode);
183 }
184
185 return 0;
186 }
187
188 static int
sun6i_wdt_tickle(struct sysmon_wdog * smw)189 sun6i_wdt_tickle(struct sysmon_wdog *smw)
190 {
191 struct sunxi_wdt_softc * const sc = smw->smw_cookie;
192 const uint32_t ctrl = SUN6I_WDT_CTRL_RSTART |
193 __SHIFTIN(SUN6I_WDT_CTRL_KEY_FIELD_V, SUN6I_WDT_CTRL_KEY_FIELD);
194
195 WDT_WRITE(sc, SUN6I_WDT_CTRL_REG, ctrl);
196
197 return 0;
198 }
199
200 static int
sunxi_wdt_match(device_t parent,cfdata_t cf,void * aux)201 sunxi_wdt_match(device_t parent, cfdata_t cf, void *aux)
202 {
203 struct fdt_attach_args * const faa = aux;
204
205 return of_compatible_match(faa->faa_phandle, compat_data);
206 }
207
208 static void
sunxi_wdt_attach(device_t parent,device_t self,void * aux)209 sunxi_wdt_attach(device_t parent, device_t self, void *aux)
210 {
211 struct sunxi_wdt_softc * const sc = device_private(self);
212 struct fdt_attach_args * const faa = aux;
213 const int phandle = faa->faa_phandle;
214 enum sunxi_wdt_type type;
215 bus_addr_t addr;
216 bus_size_t size;
217
218 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
219 aprint_error(": couldn't get registers\n");
220 return;
221 }
222
223 sc->sc_dev = self;
224 sc->sc_bst = faa->faa_bst;
225 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) {
226 aprint_error(": couldn't map registers\n");
227 return;
228 }
229 sc->sc_periods = sunxi_periods;
230
231 aprint_naive("\n");
232 aprint_normal(": Watchdog\n");
233
234 sc->sc_smw.smw_name = device_xname(self);
235 sc->sc_smw.smw_cookie = sc;
236 sc->sc_smw.smw_period = SUNXI_WDT_PERIOD_DEFAULT;
237
238 type = of_compatible_lookup(phandle, compat_data)->value;
239 switch (type) {
240 case WDT_SUN4I:
241 sc->sc_smw.smw_setmode = sun4i_wdt_setmode;
242 sc->sc_smw.smw_tickle = sun4i_wdt_tickle;
243 break;
244 case WDT_SUN6I:
245 sc->sc_smw.smw_setmode = sun6i_wdt_setmode;
246 sc->sc_smw.smw_tickle = sun6i_wdt_tickle;
247
248 /* Disable watchdog IRQs */
249 WDT_WRITE(sc, SUN6I_WDT_IRQ_EN_REG, 0);
250 break;
251 }
252
253 aprint_normal_dev(self,
254 "default watchdog period is %u seconds\n",
255 sc->sc_smw.smw_period);
256
257 if (sysmon_wdog_register(&sc->sc_smw) != 0) {
258 aprint_error_dev(self,
259 "couldn't register with sysmon\n");
260 }
261 }
262
263 CFATTACH_DECL_NEW(sunxi_wdt, sizeof(struct sunxi_wdt_softc),
264 sunxi_wdt_match, sunxi_wdt_attach, NULL, NULL);
265