xref: /openbmc/u-boot/arch/arm/cpu/armv7/cpu.c (revision db7720bad4ae0577c140fd72def24311afece894)
1 /*
2  * (C) Copyright 2008 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  * See file CREDITS for list of people who contributed to this
12  * project.
13  *
14  * This program is free software; you can redistribute it and/or
15  * modify it under the terms of the GNU General Public License as
16  * published by the Free Software Foundation; either version 2 of
17  * the License, or (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program; if not, write to the Free Software
26  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27  * MA 02111-1307 USA
28  */
29 
30 /*
31  * CPU specific code
32  */
33 
34 #include <common.h>
35 #include <command.h>
36 #include <asm/system.h>
37 #include <asm/cache.h>
38 #include <asm/armv7.h>
39 #include <linux/compiler.h>
40 
41 void __naked save_boot_params_default(u32 r0, u32 r1, u32 r2, u32 r3)
42 {
43 	/*
44 	 * Stack pointer is not yet initialized
45 	 * Don't save anything to stack even if compiled with -O0
46 	 */
47 	asm("bx lr");
48 }
49 
50 void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3)
51 	__attribute__((weak, alias("save_boot_params_default")));
52 
53 int cleanup_before_linux(void)
54 {
55 	/*
56 	 * this function is called just before we call linux
57 	 * it prepares the processor for linux
58 	 *
59 	 * we turn off caches etc ...
60 	 */
61 #ifndef CONFIG_SPL_BUILD
62 	disable_interrupts();
63 #endif
64 
65 	/*
66 	 * Turn off I-cache and invalidate it
67 	 */
68 	icache_disable();
69 	invalidate_icache_all();
70 
71 	/*
72 	 * turn off D-cache
73 	 * dcache_disable() in turn flushes the d-cache and disables MMU
74 	 */
75 	dcache_disable();
76 	v7_outer_cache_disable();
77 
78 	/*
79 	 * After D-cache is flushed and before it is disabled there may
80 	 * be some new valid entries brought into the cache. We are sure
81 	 * that these lines are not dirty and will not affect our execution.
82 	 * (because unwinding the call-stack and setting a bit in CP15 SCTRL
83 	 * is all we did during this. We have not pushed anything on to the
84 	 * stack. Neither have we affected any static data)
85 	 * So just invalidate the entire d-cache again to avoid coherency
86 	 * problems for kernel
87 	 */
88 	invalidate_dcache_all();
89 
90 	return 0;
91 }
92