1 /* $NetBSD: cycv_rstmgr.c,v 1.5 2022/01/01 13:47:19 andvar Exp $ */
2
3 /* This file is in the public domain. */
4
5 #include <sys/cdefs.h>
6 __KERNEL_RCSID(0, "$NetBSD: cycv_rstmgr.c,v 1.5 2022/01/01 13:47:19 andvar Exp $");
7
8 #include <sys/param.h>
9 #include <sys/bus.h>
10 #include <sys/device.h>
11 #include <sys/intr.h>
12 #include <sys/systm.h>
13 #include <sys/kernel.h>
14 #include <sys/atomic.h>
15 #include <sys/kmem.h>
16
17 #include <arm/altera/cycv_reg.h>
18 #include <arm/altera/cycv_var.h>
19
20 #include <dev/fdt/fdtvar.h>
21
22 static int cycv_rstmgr_match(device_t, cfdata_t, void *);
23 static void cycv_rstmgr_attach(device_t, device_t, void *);
24
25 static void *cycv_rst_acquire(device_t, const void *, size_t);
26 static void cycv_rst_release(device_t, void *);
27 static int cycv_rst_reset_assert(device_t, void *);
28 static int cycv_rst_reset_deassert(device_t, void *);
29
30 static const struct fdtbus_reset_controller_func cycv_rstmgr_funcs = {
31 cycv_rst_acquire, cycv_rst_release,
32 cycv_rst_reset_assert, cycv_rst_reset_deassert
33 };
34
35 struct cycv_rstmgr_softc {
36 device_t sc_dev;
37
38 bus_space_tag_t sc_bst;
39 bus_space_handle_t sc_bsh;
40 };
41
42 struct cycv_reset {
43 bus_addr_t address;
44 uint32_t mask;
45 };
46
47 CFATTACH_DECL_NEW(cycvrstmgr, sizeof (struct cycv_rstmgr_softc),
48 cycv_rstmgr_match, cycv_rstmgr_attach, NULL, NULL);
49
50 static struct cycv_rstmgr_softc *cycv_rstmgr_sc;
51
52 static const struct device_compatible_entry compat_data[] = {
53 { .compat = "altr,rst-mgr" },
54 DEVICE_COMPAT_EOL
55 };
56
57 static int
cycv_rstmgr_match(device_t parent,cfdata_t cf,void * aux)58 cycv_rstmgr_match(device_t parent, cfdata_t cf, void *aux)
59 {
60 struct fdt_attach_args *faa = aux;
61
62 return of_compatible_match(faa->faa_phandle, compat_data);
63 }
64
65 static void
cycv_rstmgr_attach(device_t parent,device_t self,void * aux)66 cycv_rstmgr_attach(device_t parent, device_t self, void *aux)
67 {
68 struct cycv_rstmgr_softc *sc = device_private(self);
69 struct fdt_attach_args *faa = aux;
70 int phandle = faa->faa_phandle;
71 bus_addr_t addr;
72 bus_size_t size;
73 int error;
74
75 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
76 aprint_error(": couldn't get registers\n");
77 return;
78 }
79
80 sc->sc_dev = self;
81 sc->sc_bst = faa->faa_bst;
82 error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
83 if (error) {
84 aprint_error(": couldn't map %#" PRIxBUSADDR ": %d",
85 addr, error);
86 return;
87 }
88
89 aprint_normal(": reset manager\n");
90
91 fdtbus_register_reset_controller(self, phandle, &cycv_rstmgr_funcs);
92 cycv_rstmgr_sc = sc;
93 }
94
95 static void *
cycv_rst_acquire(device_t dev,const void * data,size_t len)96 cycv_rst_acquire(device_t dev, const void *data, size_t len) {
97 struct cycv_reset *reset = NULL;
98 uint32_t value;
99
100 if (len != sizeof value)
101 goto err_decode;
102
103 value = of_decode_int(data);
104 if (value < 0 || value >
105 (CYCV_RSTMGR_MISCMODRST - CYCV_RSTMGR_MPUMODRST + 4) / 4 * 32)
106 goto err_decode;
107
108 reset = kmem_alloc(sizeof *reset, KM_SLEEP);
109 reset->address = CYCV_RSTMGR_MPUMODRST + value / 32 * 4;
110 reset->mask = 1 << (value % 32);
111
112 if (0) {
113 err_decode:
114 aprint_debug_dev(dev, "couldn't decode reset\n");
115 }
116 return reset;
117 }
118
119 static void
cycv_rst_release(device_t dev,void * r)120 cycv_rst_release(device_t dev, void *r) {
121 kmem_free(r, sizeof (struct cycv_reset));
122 }
123
124 static void
cycv_rst_reset_set(device_t dev,struct cycv_reset * reset,int set)125 cycv_rst_reset_set(device_t dev, struct cycv_reset *reset, int set) {
126 struct cycv_rstmgr_softc *sc = device_private(dev);
127 uint32_t val = bus_space_read_4(sc->sc_bst, sc->sc_bsh, reset->address);
128
129 if (set)
130 val |= reset->mask;
131 else
132 val &= ~reset->mask;
133
134 bus_space_write_4(sc->sc_bst, sc->sc_bsh, reset->address, val);
135 }
136
137 static int
cycv_rst_reset_assert(device_t dev,void * r)138 cycv_rst_reset_assert(device_t dev, void *r) {
139
140 cycv_rst_reset_set(dev, r, 1);
141
142 return 0;
143 }
144
145 static int
cycv_rst_reset_deassert(device_t dev,void * r)146 cycv_rst_reset_deassert(device_t dev, void *r) {
147
148 cycv_rst_reset_set(dev, r, 0);
149
150 return 0;
151 }
152