a20_cpu_cfg.c revision 257200 
1/*-
2 * Copyright (c) 2013 Ganbold Tsagaankhuu <ganbold@gmail.com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/* CPU configuration module for Allwinner A20 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/arm/allwinner/a20/a20_cpu_cfg.c 257200 2013-10-27 01:34:10Z ian $");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/bus.h>
35#include <sys/kernel.h>
36#include <sys/module.h>
37#include <sys/malloc.h>
38#include <sys/rman.h>
39#include <sys/timeet.h>
40#include <sys/timetc.h>
41#include <sys/watchdog.h>
42#include <machine/bus.h>
43#include <machine/cpu.h>
44#include <machine/intr.h>
45
46#include <dev/fdt/fdt_common.h>
47#include <dev/ofw/openfirm.h>
48#include <dev/ofw/ofw_bus.h>
49#include <dev/ofw/ofw_bus_subr.h>
50
51#include <machine/bus.h>
52#include <machine/fdt.h>
53
54#include "a20_cpu_cfg.h"
55
56struct a20_cpu_cfg_softc {
57	struct resource 	*res;
58	bus_space_tag_t 	bst;
59	bus_space_handle_t	bsh;
60};
61
62static struct a20_cpu_cfg_softc *a20_cpu_cfg_sc = NULL;
63
64#define cpu_cfg_read_4(sc, reg) 	\
65	bus_space_read_4((sc)->bst, (sc)->bsh, (reg))
66#define cpu_cfg_write_4(sc, reg, val)	\
67	bus_space_write_4((sc)->bst, (sc)->bsh, (reg), (val))
68
69static int
70a20_cpu_cfg_probe(device_t dev)
71{
72
73	if (ofw_bus_is_compatible(dev, "allwinner,sun7i-cpu-cfg")) {
74		device_set_desc(dev, "A20 CPU Configuration Module");
75		return(BUS_PROBE_DEFAULT);
76	}
77
78	return (ENXIO);
79}
80
81static int
82a20_cpu_cfg_attach(device_t dev)
83{
84	struct a20_cpu_cfg_softc *sc = device_get_softc(dev);
85	int rid = 0;
86
87	if (a20_cpu_cfg_sc)
88		return (ENXIO);
89
90	sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
91	if (!sc->res) {
92		device_printf(dev, "could not allocate resource\n");
93		return (ENXIO);
94	}
95
96	sc->bst = rman_get_bustag(sc->res);
97	sc->bsh = rman_get_bushandle(sc->res);
98
99	a20_cpu_cfg_sc = sc;
100
101	return (0);
102}
103
104static device_method_t a20_cpu_cfg_methods[] = {
105	DEVMETHOD(device_probe, 	a20_cpu_cfg_probe),
106	DEVMETHOD(device_attach,	a20_cpu_cfg_attach),
107	{ 0, 0 }
108};
109
110static driver_t a20_cpu_cfg_driver = {
111	"a20_cpu_cfg",
112	a20_cpu_cfg_methods,
113	sizeof(struct a20_cpu_cfg_softc),
114};
115
116static devclass_t a20_cpu_cfg_devclass;
117
118DRIVER_MODULE(a20_cpu_cfg, simplebus, a20_cpu_cfg_driver, a20_cpu_cfg_devclass, 0, 0);
119
120uint64_t
121a20_read_counter64(void)
122{
123	uint32_t lo, hi;
124
125	/* Latch counter, wait for it to be ready to read. */
126	cpu_cfg_write_4(a20_cpu_cfg_sc, OSC24M_CNT64_CTRL_REG, CNT64_RL_EN);
127	while (cpu_cfg_read_4(a20_cpu_cfg_sc, OSC24M_CNT64_CTRL_REG) & CNT64_RL_EN)
128		continue;
129
130	hi = cpu_cfg_read_4(a20_cpu_cfg_sc, OSC24M_CNT64_HIGH_REG);
131	lo = cpu_cfg_read_4(a20_cpu_cfg_sc, OSC24M_CNT64_LOW_REG);
132
133	return (((uint64_t)hi << 32) | lo);
134}
135
136