linux/arch/arm64/include/asm/arm_generic.h

101 lines
2.3 KiB
C

/*
* arch/arm64/include/asm/arm_generic.h
*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* 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_ARM_GENERIC_H
#define __ASM_ARM_GENERIC_H
#include <linux/clocksource.h>
#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
#define ARCH_TIMER_CTRL_IMASK (1 << 1)
#define ARCH_TIMER_CTRL_ISTATUS (1 << 2)
#define ARCH_TIMER_REG_CTRL 0
#define ARCH_TIMER_REG_FREQ 1
#define ARCH_TIMER_REG_TVAL 2
static inline void arch_timer_reg_write(int reg, u32 val)
{
switch (reg) {
case ARCH_TIMER_REG_CTRL:
asm volatile("msr cntp_ctl_el0, %0" : : "r" (val));
break;
case ARCH_TIMER_REG_TVAL:
asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
break;
default:
BUILD_BUG();
}
isb();
}
static inline u32 arch_timer_reg_read(int reg)
{
u32 val;
switch (reg) {
case ARCH_TIMER_REG_CTRL:
asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
break;
case ARCH_TIMER_REG_FREQ:
asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
break;
case ARCH_TIMER_REG_TVAL:
asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
break;
default:
BUILD_BUG();
}
return val;
}
static inline void __cpuinit arch_counter_enable_user_access(void)
{
u32 cntkctl;
/* Disable user access to the timers and the virtual counter. */
asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
cntkctl &= ~((3 << 8) | (1 << 1));
/* Enable user access to the physical counter and frequency. */
cntkctl |= 1;
asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
}
static inline cycle_t arch_counter_get_cntpct(void)
{
cycle_t cval;
asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
return cval;
}
static inline cycle_t arch_counter_get_cntvct(void)
{
cycle_t cval;
asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
return cval;
}
#endif