xref: /openbmc/u-boot/arch/sh/cpu/sh4/cache.c (revision 5794619e)
1 /*
2  * (C) Copyright 2007
3  * Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <command.h>
26 #include <asm/processor.h>
27 #include <asm/io.h>
28 
29 /*
30  * Jump to P2 area.
31  * When handling TLB or caches, we need to do it from P2 area.
32  */
33 #define jump_to_P2()			\
34   do {					\
35     unsigned long __dummy;		\
36     __asm__ __volatile__(		\
37 		"mov.l	1f, %0\n\t"	\
38 		"or	%1, %0\n\t"	\
39 		"jmp	@%0\n\t"	\
40 		" nop\n\t"		\
41 		".balign 4\n"		\
42 		"1:	.long 2f\n"	\
43 		"2:"			\
44 		: "=&r" (__dummy)	\
45 		: "r" (0x20000000));	\
46   } while (0)
47 
48 /*
49  * Back to P1 area.
50  */
51 #define back_to_P1()					\
52   do {							\
53     unsigned long __dummy;				\
54     __asm__ __volatile__(				\
55 		"nop;nop;nop;nop;nop;nop;nop\n\t"	\
56 		"mov.l	1f, %0\n\t"			\
57 		"jmp	@%0\n\t"			\
58 		" nop\n\t"				\
59 		".balign 4\n"				\
60 		"1:	.long 2f\n"			\
61 		"2:"					\
62 		: "=&r" (__dummy));			\
63   } while (0)
64 
65 #define CACHE_VALID       1
66 #define CACHE_UPDATED     2
67 
68 static inline void cache_wback_all(void)
69 {
70 	unsigned long addr, data, i, j;
71 
72 	jump_to_P2();
73 	for (i = 0; i < CACHE_OC_NUM_ENTRIES; i++){
74 		for (j = 0; j < CACHE_OC_NUM_WAYS; j++) {
75 			addr = CACHE_OC_ADDRESS_ARRAY | (j << CACHE_OC_WAY_SHIFT)
76 				| (i << CACHE_OC_ENTRY_SHIFT);
77 			data = inl(addr);
78 			if (data & CACHE_UPDATED) {
79 				data &= ~CACHE_UPDATED;
80 				outl(data, addr);
81 			}
82 		}
83 	}
84 	back_to_P1();
85 }
86 
87 
88 #define CACHE_ENABLE      0
89 #define CACHE_DISABLE     1
90 
91 int cache_control(unsigned int cmd)
92 {
93 	unsigned long ccr;
94 
95 	jump_to_P2();
96 	ccr = inl(CCR);
97 
98 	if (ccr & CCR_CACHE_ENABLE)
99 		cache_wback_all();
100 
101 	if (cmd == CACHE_DISABLE)
102 		outl(CCR_CACHE_STOP, CCR);
103 	else
104 		outl(CCR_CACHE_INIT, CCR);
105 	back_to_P1();
106 
107 	return 0;
108 }
109