linux/arch/arm64/include/asm/arch_timer.h
Stephen Boyd 60faddf6eb clocksource: arch_timer: Push the read/write wrappers deeper
We're going to introduce support to read and write the memory
mapped timer registers in the next patch, so push the cp15
read/write functions one level deeper. This simplifies the next
patch and makes it clearer what's going on.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
2013-08-01 01:13:37 +02:00

124 lines
2.9 KiB
C

/*
* arch/arm64/include/asm/arch_timer.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_ARCH_TIMER_H
#define __ASM_ARCH_TIMER_H
#include <asm/barrier.h>
#include <linux/init.h>
#include <linux/types.h>
#include <clocksource/arm_arch_timer.h>
/*
* These register accessors are marked inline so the compiler can
* nicely work out which register we want, and chuck away the rest of
* the code.
*/
static __always_inline
void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
{
if (access == ARCH_TIMER_PHYS_ACCESS) {
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;
}
} else if (access == ARCH_TIMER_VIRT_ACCESS) {
switch (reg) {
case ARCH_TIMER_REG_CTRL:
asm volatile("msr cntv_ctl_el0, %0" : : "r" (val));
break;
case ARCH_TIMER_REG_TVAL:
asm volatile("msr cntv_tval_el0, %0" : : "r" (val));
break;
}
}
isb();
}
static __always_inline
u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
{
u32 val;
if (access == ARCH_TIMER_PHYS_ACCESS) {
switch (reg) {
case ARCH_TIMER_REG_CTRL:
asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
break;
case ARCH_TIMER_REG_TVAL:
asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
break;
}
} else if (access == ARCH_TIMER_VIRT_ACCESS) {
switch (reg) {
case ARCH_TIMER_REG_CTRL:
asm volatile("mrs %0, cntv_ctl_el0" : "=r" (val));
break;
case ARCH_TIMER_REG_TVAL:
asm volatile("mrs %0, cntv_tval_el0" : "=r" (val));
break;
}
}
return val;
}
static inline u32 arch_timer_get_cntfrq(void)
{
u32 val;
asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
return val;
}
static inline void __cpuinit arch_counter_set_user_access(void)
{
u32 cntkctl;
/* Disable user access to the timers and the physical counter. */
asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
cntkctl &= ~((3 << 8) | (1 << 0));
/* Enable user access to the virtual counter and frequency. */
cntkctl |= (1 << 1);
asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
}
static inline u64 arch_counter_get_cntvct(void)
{
u64 cval;
isb();
asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
return cval;
}
static inline int arch_timer_arch_init(void)
{
return 0;
}
#endif