linux/arch/arm64/include/asm/cache.h
Will Deacon dda288d7e4 arm64: cache: Identify VPIPT I-caches
Add support for detecting VPIPT I-caches, as introduced by ARMv8.2.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20 16:17:02 +00:00

82 lines
2.1 KiB
C

/*
* 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/cputype.h>
#define CTR_L1IP_SHIFT 14
#define CTR_L1IP_MASK 3
#define CTR_CWG_SHIFT 24
#define CTR_CWG_MASK 15
#define CTR_L1IP(ctr) (((ctr) >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK)
#define ICACHE_POLICY_VPIPT 0
#define ICACHE_POLICY_VIPT 2
#define ICACHE_POLICY_PIPT 3
#define L1_CACHE_SHIFT 7
#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 cache aligned. 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 L1_CACHE_BYTES
#ifndef __ASSEMBLY__
#include <linux/bitops.h>
#define ICACHEF_ALIASING 0
#define ICACHEF_VPIPT 1
extern unsigned long __icache_flags;
/*
* Whilst the D-side always behaves as PIPT on AArch64, aliasing is
* permitted in the I-cache.
*/
static inline int icache_is_aliasing(void)
{
return test_bit(ICACHEF_ALIASING, &__icache_flags);
}
static inline int icache_is_vpipt(void)
{
return test_bit(ICACHEF_VPIPT, &__icache_flags);
}
static inline u32 cache_type_cwg(void)
{
return (read_cpuid_cachetype() >> CTR_CWG_SHIFT) & CTR_CWG_MASK;
}
#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