xref: /netbsd-src/sys/arch/sparc/sparc/clkctrl.c (revision 6986c1e637a8858360500d1546d587f10daff38a)
1 /*	$NetBSD: clkctrl.c,v 1.7 2022/04/20 23:32:17 macallan Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Michael Lorenz
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
19  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: clkctrl.c,v 1.7 2022/04/20 23:32:17 macallan Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/device.h>
34 #include <sys/kernel.h>
35 
36 #include <machine/autoconf.h>
37 #include <machine/cpu.h>
38 
39 #include <sparc/sparc/vaddrs.h>
40 
41 static int clkctrl_match(device_t, cfdata_t, void *);
42 static void clkctrl_attach(device_t, device_t, void *);
43 
44 CFATTACH_DECL_NEW(clkctrl, 0,
45      clkctrl_match, clkctrl_attach, NULL, NULL);
46 
47 static void tadpole_cpu_sleep(void);
48 volatile uint8_t *clkctrl_reg = NULL;
49 
50 static int
clkctrl_match(device_t parent,cfdata_t cf,void * aux)51 clkctrl_match(device_t parent, cfdata_t cf, void *aux)
52 {
53 	union obio_attach_args *uoba = aux;
54 
55 	if ((uoba->uoba_isobio4 != 0) || (clkctrl_reg != NULL))
56 		return (0);
57 
58 	return (strcmp("clk-ctrl", uoba->uoba_sbus.sa_name) == 0);
59 }
60 
61 static void
clkctrl_attach(device_t parent,device_t self,void * aux)62 clkctrl_attach(device_t parent, device_t self, void *aux)
63 {
64 	union obio_attach_args *uoba = aux;
65 	struct sbus_attach_args *sa = &uoba->uoba_sbus;
66 	bus_space_handle_t bh;
67 	struct cpu_info *cur;
68 
69 	if (clkctrl_reg != NULL) {
70 		aprint_error("unable to attach more than once\n");
71 		return;
72 	}
73 	if (sbus_bus_map(sa->sa_bustag,
74 			 sa->sa_slot, sa->sa_offset,
75 			 1,
76 			 BUS_SPACE_MAP_LINEAR, &bh) != 0) {
77 		aprint_error("unable to map register\n");
78 		return;
79 	}
80 
81 	clkctrl_reg = (volatile uint8_t *)bus_space_vaddr(sa->sa_bustag, bh);
82 
83 #ifdef DEBUG
84 	printf(" reg: %x", (uint32_t)clkctrl_reg);
85 #endif
86 	cur = curcpu();
87 	cur->idlespin = tadpole_cpu_sleep;
88 
89 	printf("\n");
90 }
91 
92 /* ARGSUSED */
93 static void
tadpole_cpu_sleep(void)94 tadpole_cpu_sleep(void)
95 {
96 
97 	if (clkctrl_reg == 0)
98 		return;
99 	*clkctrl_reg = 0;
100 }
101