xref: /netbsd-src/sys/arch/arm/vexpress/vexpress_sysreg.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: vexpress_sysreg.c,v 1.3 2017/06/30 09:19:19 jmcneill 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: vexpress_sysreg.c,v 1.3 2017/06/30 09:19:19 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 
38 #include <dev/fdt/fdtvar.h>
39 
40 #define	SYS_CFGDATA	0x00a0
41 #define	SYS_CFGCTRL	0x00a4
42 #define	 SYS_CFGCTRL_START	__BIT(31)
43 #define	 SYS_CFGCTRL_WRITE	__BIT(30)
44 #define	 SYS_CFGCTRL_FUNCTION	__BITS(25,20)
45 #define	  SYS_CFGCTRL_FUNCTION_SHUTDOWN	8
46 #define	  SYS_CFGCTRL_FUNCTION_REBOOT	9
47 #define	 SYS_CFGCTRL_SITE	__BITS(17,16)
48 #define	  SYS_CFGCTRL_SITE_MB		0
49 #define	SYS_CFGSTAT	0x00a8
50 
51 static int	vexpress_sysreg_match(device_t, cfdata_t, void *);
52 static void	vexpress_sysreg_attach(device_t, device_t, void *);
53 
54 static const char * const compatible[] = { "arm,vexpress-sysreg", NULL };
55 
56 struct vexpress_sysreg_softc {
57 	device_t		sc_dev;
58 	bus_space_tag_t		sc_bst;
59 	bus_space_handle_t	sc_bsh;
60 };
61 
62 CFATTACH_DECL_NEW(vexpress_sysreg, sizeof(struct vexpress_sysreg_softc),
63 	vexpress_sysreg_match, vexpress_sysreg_attach, NULL, NULL);
64 
65 static void
66 vexpress_sysreg_write(device_t dev, u_int func, u_int site)
67 {
68 	struct vexpress_sysreg_softc * const sc = device_private(dev);
69 
70 	const uint32_t cfgctrl = SYS_CFGCTRL_START | SYS_CFGCTRL_WRITE |
71 	    __SHIFTIN(func, SYS_CFGCTRL_FUNCTION) |
72 	    __SHIFTIN(site, SYS_CFGCTRL_SITE);
73 
74 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGSTAT, 0);
75 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGDATA, 0);
76 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGCTRL, cfgctrl);
77 }
78 
79 static void
80 vexpress_sysreg_reset(device_t dev)
81 {
82 	delay(1000000);
83 	vexpress_sysreg_write(dev, SYS_CFGCTRL_FUNCTION_REBOOT, SYS_CFGCTRL_SITE_MB);
84 }
85 
86 static void
87 vexpress_sysreg_poweroff(device_t dev)
88 {
89 	delay(1000000);
90 	vexpress_sysreg_write(dev, SYS_CFGCTRL_FUNCTION_SHUTDOWN, SYS_CFGCTRL_SITE_MB);
91 }
92 
93 static struct fdtbus_power_controller_func vexpress_sysreg_power_funcs = {
94 	.reset = vexpress_sysreg_reset,
95 	.poweroff = vexpress_sysreg_poweroff,
96 };
97 
98 static int
99 vexpress_sysreg_match(device_t parent, cfdata_t cf, void *aux)
100 {
101 	struct fdt_attach_args * const faa = aux;
102 
103 	return of_match_compatible(faa->faa_phandle, compatible);
104 }
105 
106 static void
107 vexpress_sysreg_attach(device_t parent, device_t self, void *aux)
108 {
109 	struct vexpress_sysreg_softc * const sc = device_private(self);
110 	struct fdt_attach_args * const faa = aux;
111 	const int phandle = faa->faa_phandle;
112 	bus_addr_t addr;
113 	bus_size_t size;
114 
115 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
116 		aprint_error(": missing 'reg' property\n");
117 		return;
118 	}
119 
120 	sc->sc_dev = self;
121 	sc->sc_bst = faa->faa_bst;
122 	if (bus_space_map(faa->faa_bst, addr, size, 0, &sc->sc_bsh)) {
123 		aprint_error(": couldn't map device\n");
124 		return;
125 	}
126 
127 	aprint_naive("\n");
128 	aprint_normal("\n");
129 
130 	fdtbus_register_power_controller(self, phandle,
131 	    &vexpress_sysreg_power_funcs);
132 }
133