linux/arch/arm64/include/asm/arch_timer.h
Rob Herring 0583fe478a ARM: convert arm/arm64 arch timer to use CLKSRC_OF init
This converts arm and arm64 to use CLKSRC_OF DT based initialization for
the arch timer. A new function arch_timer_arch_init is added to allow for
arch specific setup.

This has a side effect of enabling sched_clock on omap5 and exynos5. There
should not be any reason not to use the arch timers for sched_clock.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2013-04-11 15:11:15 -05:00

139 lines
3.0 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>
static inline void arch_timer_reg_write(int access, int 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;
default:
BUILD_BUG();
}
} 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;
default:
BUILD_BUG();
}
} else {
BUILD_BUG();
}
isb();
}
static inline u32 arch_timer_reg_read(int access, int 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;
default:
BUILD_BUG();
}
} 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;
default:
BUILD_BUG();
}
} else {
BUILD_BUG();
}
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_cntpct(void)
{
u64 cval;
isb();
asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
return cval;
}
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