xref: /netbsd-src/sys/arch/arm/vexpress/vexpress_sysreg.c (revision 6e54367a22fbc89a1139d033e95bec0c0cf0975b)
1 /* $NetBSD: vexpress_sysreg.c,v 1.4 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: vexpress_sysreg.c,v 1.4 2021/01/27 03:10:20 thorpej 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 struct device_compatible_entry compat_data[] = {
55 	{ .compat = "arm,vexpress-sysreg" },
56 	DEVICE_COMPAT_EOL
57 };
58 
59 struct vexpress_sysreg_softc {
60 	device_t		sc_dev;
61 	bus_space_tag_t		sc_bst;
62 	bus_space_handle_t	sc_bsh;
63 };
64 
65 CFATTACH_DECL_NEW(vexpress_sysreg, sizeof(struct vexpress_sysreg_softc),
66 	vexpress_sysreg_match, vexpress_sysreg_attach, NULL, NULL);
67 
68 static void
vexpress_sysreg_write(device_t dev,u_int func,u_int site)69 vexpress_sysreg_write(device_t dev, u_int func, u_int site)
70 {
71 	struct vexpress_sysreg_softc * const sc = device_private(dev);
72 
73 	const uint32_t cfgctrl = SYS_CFGCTRL_START | SYS_CFGCTRL_WRITE |
74 	    __SHIFTIN(func, SYS_CFGCTRL_FUNCTION) |
75 	    __SHIFTIN(site, SYS_CFGCTRL_SITE);
76 
77 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGSTAT, 0);
78 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGDATA, 0);
79 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, SYS_CFGCTRL, cfgctrl);
80 }
81 
82 static void
vexpress_sysreg_reset(device_t dev)83 vexpress_sysreg_reset(device_t dev)
84 {
85 	delay(1000000);
86 	vexpress_sysreg_write(dev, SYS_CFGCTRL_FUNCTION_REBOOT, SYS_CFGCTRL_SITE_MB);
87 }
88 
89 static void
vexpress_sysreg_poweroff(device_t dev)90 vexpress_sysreg_poweroff(device_t dev)
91 {
92 	delay(1000000);
93 	vexpress_sysreg_write(dev, SYS_CFGCTRL_FUNCTION_SHUTDOWN, SYS_CFGCTRL_SITE_MB);
94 }
95 
96 static struct fdtbus_power_controller_func vexpress_sysreg_power_funcs = {
97 	.reset = vexpress_sysreg_reset,
98 	.poweroff = vexpress_sysreg_poweroff,
99 };
100 
101 static int
vexpress_sysreg_match(device_t parent,cfdata_t cf,void * aux)102 vexpress_sysreg_match(device_t parent, cfdata_t cf, void *aux)
103 {
104 	struct fdt_attach_args * const faa = aux;
105 
106 	return of_compatible_match(faa->faa_phandle, compat_data);
107 }
108 
109 static void
vexpress_sysreg_attach(device_t parent,device_t self,void * aux)110 vexpress_sysreg_attach(device_t parent, device_t self, void *aux)
111 {
112 	struct vexpress_sysreg_softc * const sc = device_private(self);
113 	struct fdt_attach_args * const faa = aux;
114 	const int phandle = faa->faa_phandle;
115 	bus_addr_t addr;
116 	bus_size_t size;
117 
118 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
119 		aprint_error(": missing 'reg' property\n");
120 		return;
121 	}
122 
123 	sc->sc_dev = self;
124 	sc->sc_bst = faa->faa_bst;
125 	if (bus_space_map(faa->faa_bst, addr, size, 0, &sc->sc_bsh)) {
126 		aprint_error(": couldn't map device\n");
127 		return;
128 	}
129 
130 	aprint_naive("\n");
131 	aprint_normal("\n");
132 
133 	fdtbus_register_power_controller(self, phandle,
134 	    &vexpress_sysreg_power_funcs);
135 }
136