1/* $NetBSD: tegra_fuse.c,v 1.9 2021/01/27 03:10:19 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 2015 Jared D. 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: tegra_fuse.c,v 1.9 2021/01/27 03:10:19 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/kernel.h>
38
39#include <arm/nvidia/tegra_reg.h>
40#include <arm/nvidia/tegra_var.h>
41
42#include <dev/fdt/fdtvar.h>
43
44static int	tegra_fuse_match(device_t, cfdata_t, void *);
45static void	tegra_fuse_attach(device_t, device_t, void *);
46
47struct tegra_fuse_softc {
48	device_t		sc_dev;
49	bus_space_tag_t		sc_bst;
50	bus_space_handle_t	sc_bsh;
51
52	struct clk		*sc_clk;
53	struct fdtbus_reset	*sc_rst;
54};
55
56static struct tegra_fuse_softc *fuse_softc = NULL;
57
58CFATTACH_DECL_NEW(tegra_fuse, sizeof(struct tegra_fuse_softc),
59	tegra_fuse_match, tegra_fuse_attach, NULL, NULL);
60
61static const struct device_compatible_entry compat_data[] = {
62	{ .compat = "nvidia,tegra210-efuse" },
63	{ .compat = "nvidia,tegra124-efuse" },
64	DEVICE_COMPAT_EOL
65};
66
67static int
68tegra_fuse_match(device_t parent, cfdata_t cf, void *aux)
69{
70	struct fdt_attach_args * const faa = aux;
71
72	return of_compatible_match(faa->faa_phandle, compat_data);
73}
74
75static void
76tegra_fuse_attach(device_t parent, device_t self, void *aux)
77{
78	struct tegra_fuse_softc * const sc = device_private(self);
79	struct fdt_attach_args * const faa = aux;
80	bus_addr_t addr;
81	bus_size_t size;
82	int error;
83
84	if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
85		aprint_error(": couldn't get registers\n");
86		return;
87	}
88	sc->sc_clk = fdtbus_clock_get(faa->faa_phandle, "fuse");
89	if (sc->sc_clk == NULL) {
90		aprint_error(": couldn't get clock fuse\n");
91		return;
92	}
93	sc->sc_rst = fdtbus_reset_get(faa->faa_phandle, "fuse");
94	if (sc->sc_rst == NULL) {
95		aprint_error(": couldn't get reset fuse\n");
96		return;
97	}
98
99	sc->sc_dev = self;
100	sc->sc_bst = faa->faa_bst;
101	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
102	if (error) {
103		aprint_error(": couldn't map %#" PRIxBUSADDR ": %d", addr, error);
104		return;
105	}
106
107	KASSERT(fuse_softc == NULL);
108	fuse_softc = sc;
109
110	aprint_naive("\n");
111	aprint_normal(": FUSE\n");
112}
113
114uint32_t
115tegra_fuse_read(u_int offset)
116{
117	bus_space_tag_t bst;
118	bus_space_handle_t bsh;
119
120	KASSERT(fuse_softc != NULL);
121
122	bst = fuse_softc->sc_bst;
123	bsh = fuse_softc->sc_bsh;
124
125	clk_enable(fuse_softc->sc_clk);
126	const uint32_t v = bus_space_read_4(bst, bsh, 0x100 + offset);
127	clk_disable(fuse_softc->sc_clk);
128
129	return v;
130}
131