提交 0c2b6dc4 编写于 作者: L Linus Torvalds

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "This updates contains:

   - A revert which addresses a boot failure on ARM Sun5i platforms

   - A new clocksource driver, which has been delayed beyond rc1 due to
     an interrupt driver issue which was unearthed by this driver. The
     debugging of that issue and the discussion about the proper
     solution made this driver miss the merge window. There is no point
     in delaying it for a full cycle as it completes the basic mainline
     support for the new JCore platform and does not create any risk
     outside of that platform"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"
  clocksource: Add J-Core timer/clocksource driver
  of: Add J-Core timer bindings
J-Core Programmable Interval Timer and Clocksource
Required properties:
- compatible: Must be "jcore,pit".
- reg: Memory region(s) for timer/clocksource registers. For SMP,
there should be one region per cpu, indexed by the sequential,
zero-based hardware cpu number.
- interrupts: An interrupt to assign for the timer. The actual pit
core is integrated with the aic and allows the timer interrupt
assignment to be programmed by software, but this property is
required in order to reserve an interrupt number that doesn't
conflict with other devices.
Example:
timer@200 {
compatible = "jcore,pit";
reg = < 0x200 0x30 0x500 0x30 >;
interrupts = < 0x48 >;
};
......@@ -417,6 +417,16 @@ config SYS_SUPPORTS_SH_TMU
config SYS_SUPPORTS_EM_STI
bool
config CLKSRC_JCORE_PIT
bool "J-Core PIT timer driver" if COMPILE_TEST
depends on OF
depends on GENERIC_CLOCKEVENTS
depends on HAS_IOMEM
select CLKSRC_MMIO
help
This enables build of clocksource and clockevent driver for
the integrated PIT in the J-Core synthesizable, open source SoC.
config SH_TIMER_CMT
bool "Renesas CMT timer driver" if COMPILE_TEST
depends on GENERIC_CLOCKEVENTS
......
......@@ -5,6 +5,7 @@ obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o
obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o
obj-$(CONFIG_SCx200HR_TIMER) += scx200_hrt.o
obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o
obj-$(CONFIG_CLKSRC_JCORE_PIT) += jcore-pit.o
obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o
obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o
obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o
......
/*
* J-Core SoC PIT/clocksource driver
*
* Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/sched_clock.h>
#include <linux/cpu.h>
#include <linux/cpuhotplug.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#define PIT_IRQ_SHIFT 12
#define PIT_PRIO_SHIFT 20
#define PIT_ENABLE_SHIFT 26
#define PIT_PRIO_MASK 0xf
#define REG_PITEN 0x00
#define REG_THROT 0x10
#define REG_COUNT 0x14
#define REG_BUSPD 0x18
#define REG_SECHI 0x20
#define REG_SECLO 0x24
#define REG_NSEC 0x28
struct jcore_pit {
struct clock_event_device ced;
void __iomem *base;
unsigned long periodic_delta;
u32 enable_val;
};
static void __iomem *jcore_pit_base;
static struct jcore_pit __percpu *jcore_pit_percpu;
static notrace u64 jcore_sched_clock_read(void)
{
u32 seclo, nsec, seclo0;
__iomem void *base = jcore_pit_base;
seclo = readl(base + REG_SECLO);
do {
seclo0 = seclo;
nsec = readl(base + REG_NSEC);
seclo = readl(base + REG_SECLO);
} while (seclo0 != seclo);
return seclo * NSEC_PER_SEC + nsec;
}
static cycle_t jcore_clocksource_read(struct clocksource *cs)
{
return jcore_sched_clock_read();
}
static int jcore_pit_disable(struct jcore_pit *pit)
{
writel(0, pit->base + REG_PITEN);
return 0;
}
static int jcore_pit_set(unsigned long delta, struct jcore_pit *pit)
{
jcore_pit_disable(pit);
writel(delta, pit->base + REG_THROT);
writel(pit->enable_val, pit->base + REG_PITEN);
return 0;
}
static int jcore_pit_set_state_shutdown(struct clock_event_device *ced)
{
struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
return jcore_pit_disable(pit);
}
static int jcore_pit_set_state_oneshot(struct clock_event_device *ced)
{
struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
return jcore_pit_disable(pit);
}
static int jcore_pit_set_state_periodic(struct clock_event_device *ced)
{
struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
return jcore_pit_set(pit->periodic_delta, pit);
}
static int jcore_pit_set_next_event(unsigned long delta,
struct clock_event_device *ced)
{
struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
return jcore_pit_set(delta, pit);
}
static int jcore_pit_local_init(unsigned cpu)
{
struct jcore_pit *pit = this_cpu_ptr(jcore_pit_percpu);
unsigned buspd, freq;
pr_info("Local J-Core PIT init on cpu %u\n", cpu);
buspd = readl(pit->base + REG_BUSPD);
freq = DIV_ROUND_CLOSEST(NSEC_PER_SEC, buspd);
pit->periodic_delta = DIV_ROUND_CLOSEST(NSEC_PER_SEC, HZ * buspd);
clockevents_config_and_register(&pit->ced, freq, 1, ULONG_MAX);
return 0;
}
static irqreturn_t jcore_timer_interrupt(int irq, void *dev_id)
{
struct jcore_pit *pit = this_cpu_ptr(dev_id);
if (clockevent_state_oneshot(&pit->ced))
jcore_pit_disable(pit);
pit->ced.event_handler(&pit->ced);
return IRQ_HANDLED;
}
static int __init jcore_pit_init(struct device_node *node)
{
int err;
unsigned pit_irq, cpu;
unsigned long hwirq;
u32 irqprio, enable_val;
jcore_pit_base = of_iomap(node, 0);
if (!jcore_pit_base) {
pr_err("Error: Cannot map base address for J-Core PIT\n");
return -ENXIO;
}
pit_irq = irq_of_parse_and_map(node, 0);
if (!pit_irq) {
pr_err("Error: J-Core PIT has no IRQ\n");
return -ENXIO;
}
pr_info("Initializing J-Core PIT at %p IRQ %d\n",
jcore_pit_base, pit_irq);
err = clocksource_mmio_init(jcore_pit_base, "jcore_pit_cs",
NSEC_PER_SEC, 400, 32,
jcore_clocksource_read);
if (err) {
pr_err("Error registering clocksource device: %d\n", err);
return err;
}
sched_clock_register(jcore_sched_clock_read, 32, NSEC_PER_SEC);
jcore_pit_percpu = alloc_percpu(struct jcore_pit);
if (!jcore_pit_percpu) {
pr_err("Failed to allocate memory for clock event device\n");
return -ENOMEM;
}
err = request_irq(pit_irq, jcore_timer_interrupt,
IRQF_TIMER | IRQF_PERCPU,
"jcore_pit", jcore_pit_percpu);
if (err) {
pr_err("pit irq request failed: %d\n", err);
free_percpu(jcore_pit_percpu);
return err;
}
/*
* The J-Core PIT is not hard-wired to a particular IRQ, but
* integrated with the interrupt controller such that the IRQ it
* generates is programmable, as follows:
*
* The bit layout of the PIT enable register is:
*
* .....e..ppppiiiiiiii............
*
* where the .'s indicate unrelated/unused bits, e is enable,
* p is priority, and i is hard irq number.
*
* For the PIT included in AIC1 (obsolete but still in use),
* any hard irq (trap number) can be programmed via the 8
* iiiiiiii bits, and a priority (0-15) is programmable
* separately in the pppp bits.
*
* For the PIT included in AIC2 (current), the programming
* interface is equivalent modulo interrupt mapping. This is
* why a different compatible tag was not used. However only
* traps 64-127 (the ones actually intended to be used for
* interrupts, rather than syscalls/exceptions/etc.) can be
* programmed (the high 2 bits of i are ignored) and the
* priority pppp is <<2'd and or'd onto the irq number. This
* choice seems to have been made on the hardware engineering
* side under an assumption that preserving old AIC1 priority
* mappings was important. Future models will likely ignore
* the pppp field.
*/
hwirq = irq_get_irq_data(pit_irq)->hwirq;
irqprio = (hwirq >> 2) & PIT_PRIO_MASK;
enable_val = (1U << PIT_ENABLE_SHIFT)
| (hwirq << PIT_IRQ_SHIFT)
| (irqprio << PIT_PRIO_SHIFT);
for_each_present_cpu(cpu) {
struct jcore_pit *pit = per_cpu_ptr(jcore_pit_percpu, cpu);
pit->base = of_iomap(node, cpu);
if (!pit->base) {
pr_err("Unable to map PIT for cpu %u\n", cpu);
continue;
}
pit->ced.name = "jcore_pit";
pit->ced.features = CLOCK_EVT_FEAT_PERIODIC
| CLOCK_EVT_FEAT_ONESHOT
| CLOCK_EVT_FEAT_PERCPU;
pit->ced.cpumask = cpumask_of(cpu);
pit->ced.rating = 400;
pit->ced.irq = pit_irq;
pit->ced.set_state_shutdown = jcore_pit_set_state_shutdown;
pit->ced.set_state_periodic = jcore_pit_set_state_periodic;
pit->ced.set_state_oneshot = jcore_pit_set_state_oneshot;
pit->ced.set_next_event = jcore_pit_set_next_event;
pit->enable_val = enable_val;
}
cpuhp_setup_state(CPUHP_AP_JCORE_TIMER_STARTING,
"AP_JCORE_TIMER_STARTING",
jcore_pit_local_init, NULL);
return 0;
}
CLOCKSOURCE_OF_DECLARE(jcore_pit, "jcore,pit", jcore_pit_init);
......@@ -152,6 +152,13 @@ static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
static cycle_t sun5i_clksrc_read(struct clocksource *clksrc)
{
struct sun5i_timer_clksrc *cs = to_sun5i_timer_clksrc(clksrc);
return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1));
}
static int sun5i_rate_cb_clksrc(struct notifier_block *nb,
unsigned long event, void *data)
{
......@@ -210,8 +217,13 @@ static int __init sun5i_setup_clocksource(struct device_node *node,
writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
base + TIMER_CTL_REG(1));
ret = clocksource_mmio_init(base + TIMER_CNTVAL_LO_REG(1), node->name,
rate, 340, 32, clocksource_mmio_readl_down);
cs->clksrc.name = node->name;
cs->clksrc.rating = 340;
cs->clksrc.read = sun5i_clksrc_read;
cs->clksrc.mask = CLOCKSOURCE_MASK(32);
cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
ret = clocksource_register_hz(&cs->clksrc, rate);
if (ret) {
pr_err("Couldn't register clock source.\n");
goto err_remove_notifier;
......
......@@ -81,6 +81,7 @@ enum cpuhp_state {
CPUHP_AP_ARM_ARCH_TIMER_STARTING,
CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
CPUHP_AP_DUMMY_TIMER_STARTING,
CPUHP_AP_JCORE_TIMER_STARTING,
CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
CPUHP_AP_ARM_TWD_STARTING,
CPUHP_AP_METAG_TIMER_STARTING,
......
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