xref: /freebsd/sys/arm/freescale/imx/imx_machdep.c (revision 669f9224ec5398fbc825dd031415126af032cf42)
1 /*-
2  * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
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 #include "opt_platform.h"
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #define _ARM32_BUS_DMA_PRIVATE
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/reboot.h>
36 
37 #include <vm/vm.h>
38 #include <vm/pmap.h>
39 
40 #include <machine/armreg.h>
41 #include <machine/bus.h>
42 #include <machine/devmap.h>
43 #include <machine/machdep.h>
44 
45 #include <arm/freescale/imx/imx_machdep.h>
46 #include <arm/freescale/imx/imx_wdogreg.h>
47 
48 struct arm32_dma_range *
49 bus_dma_get_range(void)
50 {
51 
52 	return (NULL);
53 }
54 
55 int
56 bus_dma_get_range_nb(void)
57 {
58 
59 	return (0);
60 }
61 
62 /*
63  * This code which manipulates the watchdog hardware is here to implement
64  * cpu_reset() because the watchdog is the only way for software to reset the
65  * chip.  Why here and not in imx_wdog.c?  Because there's no requirement that
66  * the watchdog driver be compiled in, but it's nice to be able to reboot even
67  * if it's not.
68  */
69 void
70 imx_wdog_cpu_reset(vm_offset_t wdcr_physaddr)
71 {
72 	volatile uint16_t * pcr;
73 
74 	/*
75 	 * Trigger an immediate reset by clearing the SRS bit in the watchdog
76 	 * control register.  The reset happens on the next cycle of the wdog
77 	 * 32KHz clock, so hang out in a spin loop until the reset takes effect.
78 	 */
79 	if ((pcr = arm_devmap_ptov(wdcr_physaddr, sizeof(*pcr))) == NULL) {
80 		printf("cpu_reset() can't find its control register... locking up now.");
81 	} else {
82 		*pcr &= ~WDOG_CR_SRS;
83 	}
84 	for (;;)
85 		continue;
86 }
87 
88 u_int
89 imx_soc_family(void)
90 {
91 	return (imx_soc_type() >> IMXSOC_FAMSHIFT);
92 }
93 
94 
95