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-rw-r--r--Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt25
-rw-r--r--drivers/clocksource/Kconfig7
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/timer-imx-sysctr.c145
4 files changed, 178 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt b/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt
new file mode 100644
index 000000000000..d57659996d62
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/nxp,sysctr-timer.txt
@@ -0,0 +1,25 @@
+NXP System Counter Module(sys_ctr)
+
+The system counter(sys_ctr) is a programmable system counter which provides
+a shared time base to Cortex A15, A7, A53, A73, etc. it is intended for use in
+applications where the counter is always powered and support multiple,
+unrelated clocks. The compare frame inside can be used for timer purpose.
+
+Required properties:
+
+- compatible : should be "nxp,sysctr-timer"
+- reg : Specifies the base physical address and size of the comapre
+ frame and the counter control, read & compare.
+- interrupts : should be the first compare frames' interrupt
+- clocks : Specifies the counter clock.
+- clock-names: Specifies the clock's name of this module
+
+Example:
+
+ system_counter: timer@306a0000 {
+ compatible = "nxp,sysctr-timer";
+ reg = <0x306a0000 0x20000>;/* system-counter-rd & compare */
+ clocks = <&clk_8m>;
+ clock-names = "per";
+ interrupts = <GIC_SPI 47 IRQ_TYPE_LEVEL_HIGH>;
+ };
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index d17a347e813a..e9936992934a 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -617,6 +617,13 @@ config CLKSRC_IMX_TPM
Enable this option to use IMX Timer/PWM Module (TPM) timer as
clocksource.
+config TIMER_IMX_SYS_CTR
+ bool "i.MX system counter timer" if COMPILE_TEST
+ select TIMER_OF
+ help
+ Enable this option to use i.MX system counter timer as a
+ clockevent.
+
config CLKSRC_ST_LPC
bool "Low power clocksource found in the LPC" if COMPILE_TEST
select TIMER_OF if OF
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 4145b21eaed3..0939886b305f 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_CLKSRC_MIPS_GIC) += mips-gic-timer.o
obj-$(CONFIG_CLKSRC_TANGO_XTAL) += timer-tango-xtal.o
obj-$(CONFIG_CLKSRC_IMX_GPT) += timer-imx-gpt.o
obj-$(CONFIG_CLKSRC_IMX_TPM) += timer-imx-tpm.o
+obj-$(CONFIG_TIMER_IMX_SYS_CTR) += timer-imx-sysctr.o
obj-$(CONFIG_ASM9260_TIMER) += asm9260_timer.o
obj-$(CONFIG_H8300_TMR8) += h8300_timer8.o
obj-$(CONFIG_H8300_TMR16) += h8300_timer16.o
diff --git a/drivers/clocksource/timer-imx-sysctr.c b/drivers/clocksource/timer-imx-sysctr.c
new file mode 100644
index 000000000000..fd7d68066efb
--- /dev/null
+++ b/drivers/clocksource/timer-imx-sysctr.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2017-2019 NXP
+
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include "timer-of.h"
+
+#define CMP_OFFSET 0x10000
+
+#define CNTCV_LO 0x8
+#define CNTCV_HI 0xc
+#define CMPCV_LO (CMP_OFFSET + 0x20)
+#define CMPCV_HI (CMP_OFFSET + 0x24)
+#define CMPCR (CMP_OFFSET + 0x2c)
+
+#define SYS_CTR_EN 0x1
+#define SYS_CTR_IRQ_MASK 0x2
+
+static void __iomem *sys_ctr_base;
+static u32 cmpcr;
+
+static void sysctr_timer_enable(bool enable)
+{
+ writel(enable ? cmpcr | SYS_CTR_EN : cmpcr, sys_ctr_base + CMPCR);
+}
+
+static void sysctr_irq_acknowledge(void)
+{
+ /*
+ * clear the enable bit(EN =0) will clear
+ * the status bit(ISTAT = 0), then the interrupt
+ * signal will be negated(acknowledged).
+ */
+ sysctr_timer_enable(false);
+}
+
+static inline u64 sysctr_read_counter(void)
+{
+ u32 cnt_hi, tmp_hi, cnt_lo;
+
+ do {
+ cnt_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);
+ cnt_lo = readl_relaxed(sys_ctr_base + CNTCV_LO);
+ tmp_hi = readl_relaxed(sys_ctr_base + CNTCV_HI);
+ } while (tmp_hi != cnt_hi);
+
+ return ((u64) cnt_hi << 32) | cnt_lo;
+}
+
+static int sysctr_set_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ u32 cmp_hi, cmp_lo;
+ u64 next;
+
+ sysctr_timer_enable(false);
+
+ next = sysctr_read_counter();
+
+ next += delta;
+
+ cmp_hi = (next >> 32) & 0x00fffff;
+ cmp_lo = next & 0xffffffff;
+
+ writel_relaxed(cmp_hi, sys_ctr_base + CMPCV_HI);
+ writel_relaxed(cmp_lo, sys_ctr_base + CMPCV_LO);
+
+ sysctr_timer_enable(true);
+
+ return 0;
+}
+
+static int sysctr_set_state_oneshot(struct clock_event_device *evt)
+{
+ return 0;
+}
+
+static int sysctr_set_state_shutdown(struct clock_event_device *evt)
+{
+ sysctr_timer_enable(false);
+
+ return 0;
+}
+
+static irqreturn_t sysctr_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ sysctr_irq_acknowledge();
+
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static struct timer_of to_sysctr = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE,
+ .clkevt = {
+ .name = "i.MX system counter timer",
+ .features = CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_DYNIRQ,
+ .set_state_oneshot = sysctr_set_state_oneshot,
+ .set_next_event = sysctr_set_next_event,
+ .set_state_shutdown = sysctr_set_state_shutdown,
+ .rating = 200,
+ },
+ .of_irq = {
+ .handler = sysctr_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ },
+ .of_clk = {
+ .name = "per",
+ },
+};
+
+static void __init sysctr_clockevent_init(void)
+{
+ to_sysctr.clkevt.cpumask = cpumask_of(0);
+
+ clockevents_config_and_register(&to_sysctr.clkevt,
+ timer_of_rate(&to_sysctr),
+ 0xff, 0x7fffffff);
+}
+
+static int __init sysctr_timer_init(struct device_node *np)
+{
+ int ret = 0;
+
+ ret = timer_of_init(np, &to_sysctr);
+ if (ret)
+ return ret;
+
+ sys_ctr_base = timer_of_base(&to_sysctr);
+ cmpcr = readl(sys_ctr_base + CMPCR);
+ cmpcr &= ~SYS_CTR_EN;
+
+ sysctr_clockevent_init();
+
+ return 0;
+}
+TIMER_OF_DECLARE(sysctr_timer, "nxp,sysctr-timer", sysctr_timer_init);