xref: /openbmc/u-boot/arch/arm/cpu/armv7/cpu.c (revision 3ebd892f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2008 Texas Insturments
4  *
5  * (C) Copyright 2002
6  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
7  * Marius Groeger <mgroeger@sysgo.de>
8  *
9  * (C) Copyright 2002
10  * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
11  */
12 
13 /*
14  * CPU specific code
15  */
16 
17 #include <common.h>
18 #include <command.h>
19 #include <asm/system.h>
20 #include <asm/cache.h>
21 #include <asm/armv7.h>
22 #include <linux/compiler.h>
23 
24 void __weak cpu_cache_initialization(void){}
25 
26 int cleanup_before_linux_select(int flags)
27 {
28 	/*
29 	 * this function is called just before we call linux
30 	 * it prepares the processor for linux
31 	 *
32 	 * we turn off caches etc ...
33 	 */
34 #ifndef CONFIG_SPL_BUILD
35 	disable_interrupts();
36 #endif
37 
38 	if (flags & CBL_DISABLE_CACHES) {
39 		/*
40 		* turn off D-cache
41 		* dcache_disable() in turn flushes the d-cache and disables MMU
42 		*/
43 		dcache_disable();
44 		v7_outer_cache_disable();
45 
46 		/*
47 		* After D-cache is flushed and before it is disabled there may
48 		* be some new valid entries brought into the cache. We are
49 		* sure that these lines are not dirty and will not affect our
50 		* execution. (because unwinding the call-stack and setting a
51 		* bit in CP15 SCTRL is all we did during this. We have not
52 		* pushed anything on to the stack. Neither have we affected
53 		* any static data) So just invalidate the entire d-cache again
54 		* to avoid coherency problems for kernel
55 		*/
56 		invalidate_dcache_all();
57 
58 		icache_disable();
59 		invalidate_icache_all();
60 	} else {
61 		/*
62 		 * Turn off I-cache and invalidate it
63 		 */
64 		icache_disable();
65 		invalidate_icache_all();
66 
67 		flush_dcache_all();
68 		invalidate_icache_all();
69 		icache_enable();
70 	}
71 
72 	/*
73 	 * Some CPU need more cache attention before starting the kernel.
74 	 */
75 	cpu_cache_initialization();
76 
77 	return 0;
78 }
79 
80 int cleanup_before_linux(void)
81 {
82 	return cleanup_before_linux_select(CBL_ALL);
83 }
84