xref: /openbmc/u-boot/arch/arm/cpu/arm11/cpu.c (revision 44da3a17)
1 /*
2  * (C) Copyright 2004 Texas Insturments
3  *
4  * (C) Copyright 2002
5  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
6  * Marius Groeger <mgroeger@sysgo.de>
7  *
8  * (C) Copyright 2002
9  * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
10  *
11  * SPDX-License-Identifier:	GPL-2.0+
12  */
13 
14 /*
15  * CPU specific code
16  */
17 
18 #include <common.h>
19 #include <command.h>
20 #include <asm/system.h>
21 
22 static void cache_flush(void);
23 
24 int cleanup_before_linux (void)
25 {
26 	/*
27 	 * this function is called just before we call linux
28 	 * it prepares the processor for linux
29 	 *
30 	 * we turn off caches etc ...
31 	 */
32 
33 	disable_interrupts ();
34 
35 	/* turn off I/D-cache */
36 	icache_disable();
37 	dcache_disable();
38 	/* flush I/D-cache */
39 	cache_flush();
40 
41 	return 0;
42 }
43 
44 static void cache_flush(void)
45 {
46 	unsigned long i = 0;
47 	/* clean entire data cache */
48 	asm volatile("mcr p15, 0, %0, c7, c10, 0" : : "r" (i));
49 	/* invalidate both caches and flush btb */
50 	asm volatile("mcr p15, 0, %0, c7, c7, 0" : : "r" (i));
51 	/* mem barrier to sync things */
52 	asm volatile("mcr p15, 0, %0, c7, c10, 4" : : "r" (i));
53 }
54 
55 #ifndef CONFIG_SYS_DCACHE_OFF
56 
57 #ifndef CONFIG_SYS_CACHELINE_SIZE
58 #define CONFIG_SYS_CACHELINE_SIZE	32
59 #endif
60 
61 void invalidate_dcache_all(void)
62 {
63 	asm volatile("mcr p15, 0, %0, c7, c6, 0" : : "r" (0));
64 }
65 
66 void flush_dcache_all(void)
67 {
68 	asm volatile("mcr p15, 0, %0, c7, c10, 0" : : "r" (0));
69 	asm volatile("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
70 }
71 
72 static int check_cache_range(unsigned long start, unsigned long stop)
73 {
74 	int ok = 1;
75 
76 	if (start & (CONFIG_SYS_CACHELINE_SIZE - 1))
77 		ok = 0;
78 
79 	if (stop & (CONFIG_SYS_CACHELINE_SIZE - 1))
80 		ok = 0;
81 
82 	if (!ok)
83 		debug("CACHE: Misaligned operation at range [%08lx, %08lx]\n",
84 			start, stop);
85 
86 	return ok;
87 }
88 
89 void invalidate_dcache_range(unsigned long start, unsigned long stop)
90 {
91 	if (!check_cache_range(start, stop))
92 		return;
93 
94 	while (start < stop) {
95 		asm volatile("mcr p15, 0, %0, c7, c6, 1" : : "r" (start));
96 		start += CONFIG_SYS_CACHELINE_SIZE;
97 	}
98 }
99 
100 void flush_dcache_range(unsigned long start, unsigned long stop)
101 {
102 	if (!check_cache_range(start, stop))
103 		return;
104 
105 	while (start < stop) {
106 		asm volatile("mcr p15, 0, %0, c7, c14, 1" : : "r" (start));
107 		start += CONFIG_SYS_CACHELINE_SIZE;
108 	}
109 
110 	asm volatile("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
111 }
112 
113 #else /* #ifndef CONFIG_SYS_DCACHE_OFF */
114 void invalidate_dcache_all(void)
115 {
116 }
117 
118 void flush_dcache_all(void)
119 {
120 }
121 #endif /* #ifndef CONFIG_SYS_DCACHE_OFF */
122 
123 #if !defined(CONFIG_SYS_ICACHE_OFF) || !defined(CONFIG_SYS_DCACHE_OFF)
124 void enable_caches(void)
125 {
126 #ifndef CONFIG_SYS_ICACHE_OFF
127 	icache_enable();
128 #endif
129 #ifndef CONFIG_SYS_DCACHE_OFF
130 	dcache_enable();
131 #endif
132 }
133 #endif
134