armv8: add cpu core helper functions

Add helper functions to identify different armv8 variants.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
This commit is contained in:
Peng Fan 2018-10-18 14:28:17 +02:00 committed by Stefano Babic
parent 5710a48afc
commit fa64d8429b

View File

@ -0,0 +1,26 @@
/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright 2018 NXP
*/
#define MIDR_PARTNUM_CORTEX_A35 0xD04
#define MIDR_PARTNUM_CORTEX_A53 0xD03
#define MIDR_PARTNUM_CORTEX_A72 0xD08
#define MIDR_PARTNUM_SHIFT 0x4
#define MIDR_PARTNUM_MASK (0xFFF << 0x4)
static inline unsigned int read_midr(void)
{
unsigned long val;
asm volatile("mrs %0, midr_el1" : "=r" (val));
return val;
}
#define is_cortex_a35() (((read_midr() & MIDR_PARTNUM_MASK) >> \
MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A35)
#define is_cortex_a53() (((read_midr() & MIDR_PARTNUM_MASK) >> \
MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A53)
#define is_cortex_a72() (((read_midr() & MIDR_PARTNUM_MASK) >>\
MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A72)