xref: /freebsd/stand/arm64/libarm64/cache.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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 
38 static long cache_flags;
39 #define	CACHE_FLAG_DIC_OFF	(1<<0)
40 #define	CACHE_FLAG_IDC_OFF	(1<<1)
41 
42 static bool
43 get_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 
52 static bool
53 get_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 
62 static unsigned int
63 get_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 
77 void
78 cpu_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 
105 void
106 cpu_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 
124 static int
125 command_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 }
147 COMMAND_SET(cache_flags, "cache_flags", "Set cache flags", command_cache_flags);
148