summaryrefslogtreecommitdiff
path: root/arch/arm64/include/asm/cache.h
blob: f9359d32fae5274a4104ac8a8cac4f0571c84292 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
/*
 * Copyright (C) 2012 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __ASM_CACHE_H
#define __ASM_CACHE_H

#include <asm/cachetype.h>

#define L1_CACHE_SHIFT		6
#define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)

/*
 * Memory returned by kmalloc() may be used for DMA, so we must make
 * sure that all such allocations are aligned to the maximum *known*
 * cache line size on ARMv8 systems. Otherwise, unrelated code may
 * cause parts of the buffer to be read into the cache before the
 * transfer is done, causing old data to be seen by the CPU.
 */
#define ARCH_DMA_MINALIGN	(128)

#ifndef __ASSEMBLY__

#define __read_mostly __attribute__((__section__(".data..read_mostly")))

static inline int cache_line_size(void)
{
	u32 cwg = cache_type_cwg();
	return cwg ? 4 << cwg : L1_CACHE_BYTES;
}

#endif	/* __ASSEMBLY__ */

#endif