xref: /freebsd/stand/arm64/libarm64/cache.c (revision bc7512cc58af2e8bbe5bbf5ca0059b1daa1da897)
1 /*-
2  * Copyright (c) 2014 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Semihalf under
6  * the sponsorship of the FreeBSD Foundation.
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  * notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 
34 #include <machine/armreg.h>
35 #include <machine/atomic.h>
36 
37 #include <stand.h>
38 #include <efi.h>
39 
40 #include "bootstrap.h"
41 #include "cache.h"
42 
43 static long cache_flags;
44 #define	CACHE_FLAG_DIC_OFF	(1<<0)
45 #define	CACHE_FLAG_IDC_OFF	(1<<1)
46 
47 static bool
48 get_cache_dic(uint64_t ctr)
49 {
50 	if ((cache_flags & CACHE_FLAG_DIC_OFF) != 0) {
51 		return (false);
52 	}
53 
54 	return (CTR_DIC_VAL(ctr) != 0);
55 }
56 
57 static bool
58 get_cache_idc(uint64_t ctr)
59 {
60 	if ((cache_flags & CACHE_FLAG_IDC_OFF) != 0) {
61 		return (false);
62 	}
63 
64 	return (CTR_IDC_VAL(ctr) != 0);
65 }
66 
67 static unsigned int
68 get_dcache_line_size(uint64_t ctr)
69 {
70 	unsigned int dcl_size;
71 
72 	/*
73 	 * Relevant field [19:16] is LOG2
74 	 * of the number of words in DCache line
75 	 */
76 	dcl_size = CTR_DLINE_SIZE(ctr);
77 
78 	/* Size of word shifted by cache line size */
79 	return (sizeof(int) << dcl_size);
80 }
81 
82 void
83 cpu_flush_dcache(const void *ptr, size_t len)
84 {
85 	uint64_t cl_size, ctr;
86 	vm_offset_t addr, end;
87 
88 	/* Accessible from all security levels */
89 	ctr = READ_SPECIALREG(ctr_el0);
90 
91 	if (get_cache_idc(ctr)) {
92 		dsb(ishst);
93 	} else {
94 		cl_size = get_dcache_line_size(ctr);
95 
96 		/* Calculate end address to clean */
97 		end = (vm_offset_t)ptr + (vm_offset_t)len;
98 		/* Align start address to cache line */
99 		addr = (vm_offset_t)ptr;
100 		addr = rounddown2(addr, cl_size);
101 
102 		for (; addr < end; addr += cl_size)
103 			__asm __volatile("dc	civac, %0" : : "r" (addr) :
104 			    "memory");
105 		/* Full system DSB */
106 		dsb(ish);
107 	}
108 }
109 
110 void
111 cpu_inval_icache(void)
112 {
113 	uint64_t ctr;
114 
115 	/* Accessible from all security levels */
116 	ctr = READ_SPECIALREG(ctr_el0);
117 
118 	if (get_cache_dic(ctr)) {
119 		isb();
120 	} else {
121 		__asm __volatile(
122 		    "ic		ialluis	\n"
123 		    "dsb	ish	\n"
124 		    "isb		\n"
125 		    : : : "memory");
126 	}
127 }
128 
129 static int
130 command_cache_flags(int argc, char *argv[])
131 {
132 	char *cp;
133 	long new_flags;
134 
135 	if (argc == 3) {
136 		if (strcmp(argv[1], "set") == 0) {
137 			new_flags = strtol(argv[2], &cp, 0);
138 			if (cp[0] != '\0') {
139 				printf("Invalid flags\n");
140 			} else {
141 				printf("Setting cache flags to %#lx\n",
142 				    new_flags);
143 				cache_flags = new_flags;
144 				return (CMD_OK);
145 			}
146 		}
147 	}
148 
149 	printf("usage: cache_flags set <value>\n");
150 	return (CMD_ERROR);
151 }
152 COMMAND_SET(cache_flags, "cache_flags", "Set cache flags", command_cache_flags);
153