1/*-
2 * Copyright (c) 2014 The FreeBSD Foundation
3 *
4 * This software was developed by Semihalf under
5 * the sponsorship of the FreeBSD Foundation.
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/param.h>
29
30#include <machine/armreg.h>
31#include <machine/atomic.h>
32
33#include <stand.h>
34
35#include "bootstrap.h"
36#include "cache.h"
37
38static long cache_flags;
39#define	CACHE_FLAG_DIC_OFF	(1<<0)
40#define	CACHE_FLAG_IDC_OFF	(1<<1)
41
42static bool
43get_cache_dic(uint64_t ctr)
44{
45	if ((cache_flags & CACHE_FLAG_DIC_OFF) != 0) {
46		return (false);
47	}
48
49	return (CTR_DIC_VAL(ctr) != 0);
50}
51
52static bool
53get_cache_idc(uint64_t ctr)
54{
55	if ((cache_flags & CACHE_FLAG_IDC_OFF) != 0) {
56		return (false);
57	}
58
59	return (CTR_IDC_VAL(ctr) != 0);
60}
61
62static unsigned int
63get_dcache_line_size(uint64_t ctr)
64{
65	unsigned int dcl_size;
66
67	/*
68	 * Relevant field [19:16] is LOG2
69	 * of the number of words in DCache line
70	 */
71	dcl_size = CTR_DLINE_SIZE(ctr);
72
73	/* Size of word shifted by cache line size */
74	return (sizeof(int) << dcl_size);
75}
76
77void
78cpu_flush_dcache(const void *ptr, size_t len)
79{
80	uint64_t cl_size, ctr;
81	vm_offset_t addr, end;
82
83	/* Accessible from all security levels */
84	ctr = READ_SPECIALREG(ctr_el0);
85
86	if (get_cache_idc(ctr)) {
87		dsb(ishst);
88	} else {
89		cl_size = get_dcache_line_size(ctr);
90
91		/* Calculate end address to clean */
92		end = (vm_offset_t)ptr + (vm_offset_t)len;
93		/* Align start address to cache line */
94		addr = (vm_offset_t)ptr;
95		addr = rounddown2(addr, cl_size);
96
97		for (; addr < end; addr += cl_size)
98			__asm __volatile("dc	civac, %0" : : "r" (addr) :
99			    "memory");
100		/* Full system DSB */
101		dsb(ish);
102	}
103}
104
105void
106cpu_inval_icache(void)
107{
108	uint64_t ctr;
109
110	/* Accessible from all security levels */
111	ctr = READ_SPECIALREG(ctr_el0);
112
113	if (get_cache_dic(ctr)) {
114		isb();
115	} else {
116		__asm __volatile(
117		    "ic		ialluis	\n"
118		    "dsb	ish	\n"
119		    "isb		\n"
120		    : : : "memory");
121	}
122}
123
124static int
125command_cache_flags(int argc, char *argv[])
126{
127	char *cp;
128	long new_flags;
129
130	if (argc == 3) {
131		if (strcmp(argv[1], "set") == 0) {
132			new_flags = strtol(argv[2], &cp, 0);
133			if (cp[0] != '\0') {
134				printf("Invalid flags\n");
135			} else {
136				printf("Setting cache flags to %#lx\n",
137				    new_flags);
138				cache_flags = new_flags;
139				return (CMD_OK);
140			}
141		}
142	}
143
144	printf("usage: cache_flags set <value>\n");
145	return (CMD_ERROR);
146}
147COMMAND_SET(cache_flags, "cache_flags", "Set cache flags", command_cache_flags);
148