xref: /netbsd-src/sys/arch/virt68k/dev/virtctrl.c (revision 1f20ceebeeff5b393e61526942fdb815c6e1e027)
1 /*	$NetBSD: virtctrl.c,v 1.2 2024/01/06 21:49:59 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2024 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: virtctrl.c,v 1.2 2024/01/06 21:49:59 thorpej Exp $");
34 
35 #include <sys/types.h>
36 #include <sys/bus.h>
37 #include <sys/device.h>
38 #include <sys/reboot.h>
39 #include <sys/systm.h>
40 
41 #include <machine/cpu.h>
42 
43 #include <virt68k/dev/mainbusvar.h>
44 
45 struct virtctrl_softc {
46 	device_t		sc_dev;
47 	bus_space_tag_t		sc_bst;
48 	bus_space_handle_t	sc_bsh;
49 };
50 
51 static const struct device_compatible_entry compat_data[] = {
52 	{ .compat = "netbsd,qemu-virt-ctrl" },
53 	DEVICE_COMPAT_EOL
54 };
55 
56 #define	VIRTCTRL_REG_FEATURES	0x00
57 #define	VIRTCTRL_REG_CMD	0x04
58 
59 #define	CMD_NOP			0
60 #define	CMD_RESET		1
61 #define	CMD_HALT		2
62 #define	CMD_PANIC		3
63 
64 #define	REG_READ(sc, r)		\
65 	bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (r))
66 #define	REG_WRITE(sc, r, v)	\
67 	bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (r), (v))
68 
69 static void
virtctrl_reset_handler(void * v,int howto)70 virtctrl_reset_handler(void *v, int howto)
71 {
72 	struct virtctrl_softc * const sc = v;
73 
74 	if (panicstr != NULL) {
75 		/*
76 		 * XXX N.B. This forces a shutdown, rather than
77 		 * XXX a reboot.
78 		 */
79 		REG_WRITE(sc, VIRTCTRL_REG_CMD, CMD_PANIC);
80 	} else if (howto & RB_HALT) {
81 		REG_WRITE(sc, VIRTCTRL_REG_CMD, CMD_HALT);
82 	} else {
83 		REG_WRITE(sc, VIRTCTRL_REG_CMD, CMD_RESET);
84 	}
85 }
86 
87 static int
virtctrl_match(device_t parent,cfdata_t cf,void * aux)88 virtctrl_match(device_t parent, cfdata_t cf, void *aux)
89 {
90 	struct mainbus_attach_args * const ma = aux;
91 
92 	return mainbus_compatible_match(ma, compat_data);
93 }
94 
95 static void
virtctrl_attach(device_t parent,device_t self,void * aux)96 virtctrl_attach(device_t parent, device_t self, void *aux)
97 {
98 	struct virtctrl_softc * const sc = device_private(self);
99 	struct mainbus_attach_args * const ma = aux;
100 	uint32_t feat;
101 
102 	sc->sc_dev = self;
103 	sc->sc_bst = ma->ma_st;
104 	if (bus_space_map(sc->sc_bst, ma->ma_addr, ma->ma_size, 0,
105 			  &sc->sc_bsh) != 0) {
106 		aprint_error(": couldn't map registers\n");
107 		return;
108 	}
109 
110 	aprint_naive("\n");
111 	aprint_normal(": Qemu Virtual System Controller\n");
112 
113 	feat = REG_READ(sc, VIRTCTRL_REG_FEATURES);
114 	aprint_normal_dev(self, "features=0x%08x\n", feat);
115 
116 	cpu_set_reset_func(virtctrl_reset_handler, sc);
117 }
118 
119 CFATTACH_DECL_NEW(virtctrl, sizeof(struct virtctrl_softc),
120 	virtctrl_match, virtctrl_attach, NULL, NULL);
121