1 /* $NetBSD: sunxi_resets.c,v 1.2 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_resets.c,v 1.2 2021/01/27 03:10:20 thorpej Exp $");
31
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/cpu.h>
35 #include <sys/device.h>
36
37 #include <dev/fdt/fdtvar.h>
38
39 #include <dev/clk/clk_backend.h>
40
41 #define RESET_REG(index) (((index) / 32) * 4)
42 #define RESET_MASK(index) __BIT((index) % 32)
43
44 static const struct device_compatible_entry compat_data[] = {
45 { .compat = "allwinner,sun6i-a31-clock-reset" },
46 DEVICE_COMPAT_EOL
47 };
48
49 struct sunxi_resets_softc {
50 device_t sc_dev;
51 bus_space_tag_t sc_bst;
52 bus_space_handle_t sc_bsh;
53 };
54
55 #define RESET_READ(sc, reg) \
56 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
57 #define RESET_WRITE(sc, reg, val) \
58 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
59
60 static void *
sunxi_resets_acquire(device_t dev,const void * data,size_t len)61 sunxi_resets_acquire(device_t dev, const void *data, size_t len)
62 {
63 if (len != 4)
64 return NULL;
65
66 /* Specifier is an index. Just return it. */
67 return (void *)(uintptr_t)be32dec(data);
68 }
69
70 static void
sunxi_resets_release(device_t dev,void * priv)71 sunxi_resets_release(device_t dev, void *priv)
72 {
73 }
74
75 static int
sunxi_resets_assert(device_t dev,void * priv)76 sunxi_resets_assert(device_t dev, void *priv)
77 {
78 struct sunxi_resets_softc * const sc = device_private(dev);
79 const uintptr_t index = (uintptr_t)priv;
80
81 const bus_size_t reset_reg = RESET_REG(index);
82 const uint32_t reset_mask = RESET_MASK(index);
83
84 const uint32_t val = RESET_READ(sc, reset_reg);
85 RESET_WRITE(sc, reset_reg, val & ~reset_mask);
86
87 return 0;
88 }
89
90 static int
sunxi_resets_deassert(device_t dev,void * priv)91 sunxi_resets_deassert(device_t dev, void *priv)
92 {
93 struct sunxi_resets_softc * const sc = device_private(dev);
94 const uintptr_t index = (uintptr_t)priv;
95
96 const bus_size_t reset_reg = RESET_REG(index);
97 const uint32_t reset_mask = RESET_MASK(index);
98
99 const uint32_t val = RESET_READ(sc, reset_reg);
100 RESET_WRITE(sc, reset_reg, val | reset_mask);
101
102 return 0;
103 }
104
105 static const struct fdtbus_reset_controller_func sunxi_fdtreset_funcs = {
106 .acquire = sunxi_resets_acquire,
107 .release = sunxi_resets_release,
108 .reset_assert = sunxi_resets_assert,
109 .reset_deassert = sunxi_resets_deassert,
110 };
111
112 static int
sunxi_resets_match(device_t parent,cfdata_t cf,void * aux)113 sunxi_resets_match(device_t parent, cfdata_t cf, void *aux)
114 {
115 struct fdt_attach_args * const faa = aux;
116
117 return of_compatible_match(faa->faa_phandle, compat_data);
118 }
119
120 static void
sunxi_resets_attach(device_t parent,device_t self,void * aux)121 sunxi_resets_attach(device_t parent, device_t self, void *aux)
122 {
123 struct sunxi_resets_softc * const sc = device_private(self);
124 struct fdt_attach_args * const faa = aux;
125 const int phandle = faa->faa_phandle;
126 bus_addr_t addr;
127 bus_size_t size;
128
129 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
130 aprint_error(": couldn't get registers\n");
131 return;
132 }
133
134 sc->sc_dev = self;
135 sc->sc_bst = faa->faa_bst;
136 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) {
137 aprint_error(": couldn't map registers\n");
138 return;
139 }
140
141 aprint_naive("\n");
142 aprint_normal("\n");
143
144 fdtbus_register_reset_controller(sc->sc_dev, phandle,
145 &sunxi_fdtreset_funcs);
146 }
147
148 CFATTACH_DECL_NEW(sunxi_resets, sizeof(struct sunxi_resets_softc),
149 sunxi_resets_match, sunxi_resets_attach, NULL, NULL);
150