linux/include/clocksource/arm_arch_timer.h
Julien Thierry ec5c8e429d arm_arch_timer: Expose event stream status
The arch timer configuration for a CPU might get reset after suspending
said CPU.

In order to reliably use the event stream in the kernel (e.g. for delays),
we keep track of the state where we can safely consider the event stream as
properly configured. After writing to cntkctl, we issue an ISB to ensure
that subsequent delay loops can rely on the event stream being enabled.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-13 18:55:05 +01:00

118 lines
2.9 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 __CLKSOURCE_ARM_ARCH_TIMER_H
#define __CLKSOURCE_ARM_ARCH_TIMER_H
#include <linux/bitops.h>
#include <linux/timecounter.h>
#include <linux/types.h>
#define ARCH_TIMER_TYPE_CP15 BIT(0)
#define ARCH_TIMER_TYPE_MEM BIT(1)
#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
#define ARCH_TIMER_CTRL_IT_MASK (1 << 1)
#define ARCH_TIMER_CTRL_IT_STAT (1 << 2)
#define CNTHCTL_EL1PCTEN (1 << 0)
#define CNTHCTL_EL1PCEN (1 << 1)
#define CNTHCTL_EVNTEN (1 << 2)
#define CNTHCTL_EVNTDIR (1 << 3)
#define CNTHCTL_EVNTI (0xF << 4)
enum arch_timer_reg {
ARCH_TIMER_REG_CTRL,
ARCH_TIMER_REG_TVAL,
};
enum arch_timer_ppi_nr {
ARCH_TIMER_PHYS_SECURE_PPI,
ARCH_TIMER_PHYS_NONSECURE_PPI,
ARCH_TIMER_VIRT_PPI,
ARCH_TIMER_HYP_PPI,
ARCH_TIMER_MAX_TIMER_PPI
};
enum arch_timer_spi_nr {
ARCH_TIMER_PHYS_SPI,
ARCH_TIMER_VIRT_SPI,
ARCH_TIMER_MAX_TIMER_SPI
};
#define ARCH_TIMER_PHYS_ACCESS 0
#define ARCH_TIMER_VIRT_ACCESS 1
#define ARCH_TIMER_MEM_PHYS_ACCESS 2
#define ARCH_TIMER_MEM_VIRT_ACCESS 3
#define ARCH_TIMER_MEM_MAX_FRAMES 8
#define ARCH_TIMER_USR_PCT_ACCESS_EN (1 << 0) /* physical counter */
#define ARCH_TIMER_USR_VCT_ACCESS_EN (1 << 1) /* virtual counter */
#define ARCH_TIMER_VIRT_EVT_EN (1 << 2)
#define ARCH_TIMER_EVT_TRIGGER_SHIFT (4)
#define ARCH_TIMER_EVT_TRIGGER_MASK (0xF << ARCH_TIMER_EVT_TRIGGER_SHIFT)
#define ARCH_TIMER_USR_VT_ACCESS_EN (1 << 8) /* virtual timer registers */
#define ARCH_TIMER_USR_PT_ACCESS_EN (1 << 9) /* physical timer registers */
#define ARCH_TIMER_EVT_STREAM_FREQ 10000 /* 100us */
struct arch_timer_kvm_info {
struct timecounter timecounter;
int virtual_irq;
};
struct arch_timer_mem_frame {
bool valid;
phys_addr_t cntbase;
size_t size;
int phys_irq;
int virt_irq;
};
struct arch_timer_mem {
phys_addr_t cntctlbase;
size_t size;
struct arch_timer_mem_frame frame[ARCH_TIMER_MEM_MAX_FRAMES];
};
#ifdef CONFIG_ARM_ARCH_TIMER
extern u32 arch_timer_get_rate(void);
extern u64 (*arch_timer_read_counter)(void);
extern struct arch_timer_kvm_info *arch_timer_get_kvm_info(void);
extern bool arch_timer_evtstrm_available(void);
#else
static inline u32 arch_timer_get_rate(void)
{
return 0;
}
static inline u64 arch_timer_read_counter(void)
{
return 0;
}
static inline bool arch_timer_evtstrm_available(void)
{
return false;
}
#endif
#endif