linux/include/clocksource/arm_arch_timer.h
Marc Zyngier 8c4b810a87 clocksource/drivers/arm_arch_timer: Use event stream scaling when available
With FEAT_ECV and the 1GHz counter, it is pretty likely that the
event stream divider doesn't fit in the field that holds the
divider value (we only have 4 bits to describe counter bits [15:0]

Thankfully, FEAT_ECV also provides a scaling mechanism to switch
the field to cover counter bits [23:8] instead.

Enable this on arm64 when ECV is available (32bit doesn't have
any detection infrastructure and is unlikely to be run on an
ARMv8.6 system anyway).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220203170502.2694422-1-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2022-03-07 18:27:22 +01:00

112 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#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_CVAL,
};
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_HYP_VIRT_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_INTERVAL_SCALE (1 << 17) /* EVNTIS in the ARMv8 ARM */
#define ARCH_TIMER_EVT_STREAM_PERIOD_US 100
#define ARCH_TIMER_EVT_STREAM_FREQ \
(USEC_PER_SEC / ARCH_TIMER_EVT_STREAM_PERIOD_US)
struct arch_timer_kvm_info {
struct timecounter timecounter;
int virtual_irq;
int physical_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