xref: /freebsd/stand/arm64/libarm64/cache.c (revision 2bfd8b5b9419b0ceb3dd0295fdf413d32969e5b2)
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/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 
33 #include <machine/armreg.h>
34 #include <machine/atomic.h>
35 
36 #include <stand.h>
37 #include <efi.h>
38 
39 #include "bootstrap.h"
40 #include "cache.h"
41 
42 static long cache_flags;
43 #define	CACHE_FLAG_DIC_OFF	(1<<0)
44 #define	CACHE_FLAG_IDC_OFF	(1<<1)
45 
46 static bool
47 get_cache_dic(uint64_t ctr)
48 {
49 	if ((cache_flags & CACHE_FLAG_DIC_OFF) != 0) {
50 		return (false);
51 	}
52 
53 	return (CTR_DIC_VAL(ctr) != 0);
54 }
55 
56 static bool
57 get_cache_idc(uint64_t ctr)
58 {
59 	if ((cache_flags & CACHE_FLAG_IDC_OFF) != 0) {
60 		return (false);
61 	}
62 
63 	return (CTR_IDC_VAL(ctr) != 0);
64 }
65 
66 static unsigned int
67 get_dcache_line_size(uint64_t ctr)
68 {
69 	unsigned int dcl_size;
70 
71 	/*
72 	 * Relevant field [19:16] is LOG2
73 	 * of the number of words in DCache line
74 	 */
75 	dcl_size = CTR_DLINE_SIZE(ctr);
76 
77 	/* Size of word shifted by cache line size */
78 	return (sizeof(int) << dcl_size);
79 }
80 
81 void
82 cpu_flush_dcache(const void *ptr, size_t len)
83 {
84 	uint64_t cl_size, ctr;
85 	vm_offset_t addr, end;
86 
87 	/* Accessible from all security levels */
88 	ctr = READ_SPECIALREG(ctr_el0);
89 
90 	if (get_cache_idc(ctr)) {
91 		dsb(ishst);
92 	} else {
93 		cl_size = get_dcache_line_size(ctr);
94 
95 		/* Calculate end address to clean */
96 		end = (vm_offset_t)ptr + (vm_offset_t)len;
97 		/* Align start address to cache line */
98 		addr = (vm_offset_t)ptr;
99 		addr = rounddown2(addr, cl_size);
100 
101 		for (; addr < end; addr += cl_size)
102 			__asm __volatile("dc	civac, %0" : : "r" (addr) :
103 			    "memory");
104 		/* Full system DSB */
105 		dsb(ish);
106 	}
107 }
108 
109 void
110 cpu_inval_icache(void)
111 {
112 	uint64_t ctr;
113 
114 	/* Accessible from all security levels */
115 	ctr = READ_SPECIALREG(ctr_el0);
116 
117 	if (get_cache_dic(ctr)) {
118 		isb();
119 	} else {
120 		__asm __volatile(
121 		    "ic		ialluis	\n"
122 		    "dsb	ish	\n"
123 		    "isb		\n"
124 		    : : : "memory");
125 	}
126 }
127 
128 static int
129 command_cache_flags(int argc, char *argv[])
130 {
131 	char *cp;
132 	long new_flags;
133 
134 	if (argc == 3) {
135 		if (strcmp(argv[1], "set") == 0) {
136 			new_flags = strtol(argv[2], &cp, 0);
137 			if (cp[0] != '\0') {
138 				printf("Invalid flags\n");
139 			} else {
140 				printf("Setting cache flags to %#lx\n",
141 				    new_flags);
142 				cache_flags = new_flags;
143 				return (CMD_OK);
144 			}
145 		}
146 	}
147 
148 	printf("usage: cache_flags set <value>\n");
149 	return (CMD_ERROR);
150 }
151 COMMAND_SET(cache_flags, "cache_flags", "Set cache flags", command_cache_flags);
152