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      1 /* $NetBSD: sunxi_wdt.c,v 1.7 2026/03/18 06:37:09 skrll Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2017 Jared McNeill <jmcneill (at) 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 1.7 2026/03/18 06:37:09 skrll 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 #define	 SUNXI_WDT_KEY_FIELD		__BITS(31,16)
     72 #define	  SUNXI_WDT_KEY_FIELD_V		0x16aa
     73 
     74 static const int sunxi_periods[] = {
     75 	500, 1000, 2000, 3000,
     76 	4000, 5000, 6000, 8000,
     77 	10000, 12000, 14000, 16000,
     78 	-1
     79 };
     80 
     81 enum sunxi_wdt_type {
     82 	WDT_SUN4I = 1,
     83 	WDT_SUN6I,
     84 	WDT_SUN20I,
     85 };
     86 
     87 static const struct device_compatible_entry compat_data[] = {
     88 	{ .compat = "allwinner,sun4i-a10-wdt",	.value = WDT_SUN4I },
     89 	{ .compat = "allwinner,sun6i-a31-wdt",	.value = WDT_SUN6I },
     90 	{ .compat = "allwinner,sun20i-d1-wdt",	.value = WDT_SUN20I },
     91 	DEVICE_COMPAT_EOL
     92 };
     93 
     94 struct sunxi_wdt_softc {
     95 	device_t sc_dev;
     96 	bus_space_tag_t sc_bst;
     97 	bus_space_handle_t sc_bsh;
     98 
     99 	const int *sc_periods;
    100 
    101 	struct sysmon_wdog sc_smw;
    102 };
    103 
    104 #define WDT_READ(sc, reg) \
    105     bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
    106 #define WDT_WRITE(sc, reg, val) \
    107     bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
    108 
    109 static int
    110 sunxi_wdt_map_period(struct sunxi_wdt_softc *sc, u_int period,
    111     u_int *aperiod)
    112 {
    113 	const int *p = sc->sc_periods;
    114 	int i;
    115 
    116 	if (period == 0)
    117 		return -1;
    118 
    119 	for (i = 0; *p != -1; i++, p++)
    120 		if (*p >= period * 1000) {
    121 			*aperiod = *p / 1000;
    122 			return i;
    123 		}
    124 
    125 	return -1;
    126 }
    127 
    128 static int
    129 sun4i_wdt_setmode(struct sysmon_wdog *smw)
    130 {
    131 	struct sunxi_wdt_softc * const sc = smw->smw_cookie;
    132 	uint32_t mode;
    133 	int intv;
    134 
    135 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
    136 		WDT_WRITE(sc, SUN4I_WDT_MODE_REG, 0);
    137 	} else {
    138 		if (smw->smw_period == WDOG_PERIOD_DEFAULT)
    139 			smw->smw_period = SUNXI_WDT_PERIOD_DEFAULT;
    140 		intv = sunxi_wdt_map_period(sc, smw->smw_period,
    141 		    &sc->sc_smw.smw_period);
    142 		if (intv == -1)
    143 			return EINVAL;
    144 
    145 		mode = SUN4I_WDT_MODE_EN | SUN4I_WDT_MODE_RST_EN |
    146 		    __SHIFTIN(intv, SUN4I_WDT_MODE_INTV);
    147 
    148 		WDT_WRITE(sc, SUN4I_WDT_MODE_REG, mode);
    149 	}
    150 
    151 	return 0;
    152 }
    153 
    154 static int
    155 sun4i_wdt_tickle(struct sysmon_wdog *smw)
    156 {
    157 	struct sunxi_wdt_softc * const sc = smw->smw_cookie;
    158 	const uint32_t ctrl = SUN4I_WDT_CTRL_RSTART |
    159 	    __SHIFTIN(SUN4I_WDT_CTRL_KEY_FIELD_V, SUN4I_WDT_CTRL_KEY_FIELD);
    160 
    161 	WDT_WRITE(sc, SUN4I_WDT_CTRL_REG, ctrl);
    162 
    163 	return 0;
    164 }
    165 
    166 static int
    167 sun6i_wdt_setmode(struct sysmon_wdog *smw)
    168 {
    169 	struct sunxi_wdt_softc * const sc = smw->smw_cookie;
    170 	uint32_t cfg, mode;
    171 	int intv;
    172 
    173 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
    174 		WDT_WRITE(sc, SUN6I_WDT_MODE_REG, 0);
    175 	} else {
    176 		if (smw->smw_period == WDOG_PERIOD_DEFAULT)
    177 			smw->smw_period = SUNXI_WDT_PERIOD_DEFAULT;
    178 		intv = sunxi_wdt_map_period(sc, smw->smw_period,
    179 		    &sc->sc_smw.smw_period);
    180 		if (intv == -1)
    181 			return EINVAL;
    182 
    183 		cfg = __SHIFTIN(SUN6I_WDT_CFG_CONFIG_SYS, SUN6I_WDT_CFG_CONFIG);
    184 		mode = SUN6I_WDT_MODE_EN | __SHIFTIN(intv, SUN6I_WDT_MODE_INTV);
    185 
    186 		WDT_WRITE(sc, SUN6I_WDT_CFG_REG, cfg);
    187 		WDT_WRITE(sc, SUN6I_WDT_MODE_REG, mode);
    188 	}
    189 
    190 	return 0;
    191 }
    192 
    193 static int
    194 sun6i_wdt_tickle(struct sysmon_wdog *smw)
    195 {
    196 	struct sunxi_wdt_softc * const sc = smw->smw_cookie;
    197 	const uint32_t ctrl = SUN6I_WDT_CTRL_RSTART |
    198 	    __SHIFTIN(SUN6I_WDT_CTRL_KEY_FIELD_V, SUN6I_WDT_CTRL_KEY_FIELD);
    199 
    200 	WDT_WRITE(sc, SUN6I_WDT_CTRL_REG, ctrl);
    201 
    202 	return 0;
    203 }
    204 
    205 static int
    206 sun20i_wdt_setmode(struct sysmon_wdog *smw)
    207 {
    208 	struct sunxi_wdt_softc * const sc = smw->smw_cookie;
    209 	uint32_t cfg, mode;
    210 	int intv;
    211 
    212 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
    213 		mode = __SHIFTIN(SUNXI_WDT_KEY_FIELD_V, SUNXI_WDT_KEY_FIELD);
    214 		WDT_WRITE(sc, SUN6I_WDT_MODE_REG, mode);
    215 	} else {
    216 		if (smw->smw_period == WDOG_PERIOD_DEFAULT)
    217 			smw->smw_period = SUNXI_WDT_PERIOD_DEFAULT;
    218 		intv = sunxi_wdt_map_period(sc, smw->smw_period,
    219 		    &sc->sc_smw.smw_period);
    220 		if (intv == -1)
    221 			return EINVAL;
    222 
    223 		cfg = __SHIFTIN(SUN6I_WDT_CFG_CONFIG_SYS, SUN6I_WDT_CFG_CONFIG);
    224 		cfg |= __SHIFTIN(SUNXI_WDT_KEY_FIELD_V, SUNXI_WDT_KEY_FIELD);
    225 		mode = SUN6I_WDT_MODE_EN | __SHIFTIN(intv, SUN6I_WDT_MODE_INTV);
    226 		mode |= __SHIFTIN(SUNXI_WDT_KEY_FIELD_V, SUNXI_WDT_KEY_FIELD);
    227 
    228 		WDT_WRITE(sc, SUN6I_WDT_CFG_REG, cfg);
    229 		WDT_WRITE(sc, SUN6I_WDT_MODE_REG, mode);
    230 	}
    231 
    232 	return 0;
    233 }
    234 
    235 static int
    236 sunxi_wdt_match(device_t parent, cfdata_t cf, void *aux)
    237 {
    238 	struct fdt_attach_args * const faa = aux;
    239 
    240 	return of_compatible_match(faa->faa_phandle, compat_data);
    241 }
    242 
    243 static void
    244 sunxi_wdt_attach(device_t parent, device_t self, void *aux)
    245 {
    246 	struct sunxi_wdt_softc * const sc = device_private(self);
    247 	struct fdt_attach_args * const faa = aux;
    248 	const int phandle = faa->faa_phandle;
    249 	enum sunxi_wdt_type type;
    250 	bus_addr_t addr;
    251 	bus_size_t size;
    252 	uint32_t mode;
    253 
    254 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
    255 		aprint_error(": couldn't get registers\n");
    256 		return;
    257 	}
    258 
    259 	sc->sc_dev = self;
    260 	sc->sc_bst = faa->faa_bst;
    261 	if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) {
    262 		aprint_error(": couldn't map registers\n");
    263 		return;
    264 	}
    265 	sc->sc_periods = sunxi_periods;
    266 
    267 	aprint_naive("\n");
    268 	aprint_normal(": Watchdog\n");
    269 
    270 	sc->sc_smw.smw_name = device_xname(self);
    271 	sc->sc_smw.smw_cookie = sc;
    272 	sc->sc_smw.smw_period = SUNXI_WDT_PERIOD_DEFAULT;
    273 
    274 	type = of_compatible_lookup(phandle, compat_data)->value;
    275 	switch (type) {
    276 	case WDT_SUN4I:
    277 		sc->sc_smw.smw_setmode = sun4i_wdt_setmode;
    278 		sc->sc_smw.smw_tickle = sun4i_wdt_tickle;
    279 		break;
    280 	case WDT_SUN6I:
    281 		sc->sc_smw.smw_setmode = sun6i_wdt_setmode;
    282 		sc->sc_smw.smw_tickle = sun6i_wdt_tickle;
    283 
    284 		/* Disable watchdog IRQs */
    285 		WDT_WRITE(sc, SUN6I_WDT_IRQ_EN_REG, 0);
    286 		break;
    287 	case WDT_SUN20I:
    288 		sc->sc_smw.smw_setmode = sun20i_wdt_setmode;
    289 		sc->sc_smw.smw_tickle = sun6i_wdt_tickle;
    290 
    291 		/* Disable watchdog */
    292 		mode = __SHIFTIN(SUNXI_WDT_KEY_FIELD_V, SUNXI_WDT_KEY_FIELD);
    293 		WDT_WRITE(sc, SUN6I_WDT_MODE_REG, mode);
    294 
    295 		/* Disable watchdog IRQs */
    296 		WDT_WRITE(sc, SUN6I_WDT_IRQ_EN_REG, 0);
    297 		break;
    298 	}
    299 
    300 	aprint_normal_dev(self,
    301 	    "default watchdog period is %u seconds\n",
    302 	    sc->sc_smw.smw_period);
    303 
    304 	if (sysmon_wdog_register(&sc->sc_smw) != 0) {
    305 		aprint_error_dev(self,
    306 		    "couldn't register with sysmon\n");
    307 	}
    308 }
    309 
    310 CFATTACH_DECL_NEW(sunxi_wdt, sizeof(struct sunxi_wdt_softc),
    311 	sunxi_wdt_match, sunxi_wdt_attach, NULL, NULL);
    312