[tip:timers/core] clocksource/drivers/spreadtrum: Add timer driver for the Spreadtrum SC9860 platform
From: tip-bot for Baolin Wang
Date: Mon Jan 08 2018 - 12:33:46 EST
Commit-ID: 067bc9144766495650e621b79bd2bc199cee0769
Gitweb: https://git.kernel.org/tip/067bc9144766495650e621b79bd2bc199cee0769
Author: Baolin Wang <baolin.wang@xxxxxxxxxxxxxx>
AuthorDate: Mon, 8 Jan 2018 14:28:47 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 8 Jan 2018 17:57:24 +0100
clocksource/drivers/spreadtrum: Add timer driver for the Spreadtrum SC9860 platform
The Spreadtrum SC9860 platform will use the architected timers as local
clock events, but we also need a broadcast timer device to wake up the
CPUs when the CPUs are in sleep mode.
The Spreadtrum timer can support 32-bit or 64-bit counters, as well as
supporting period mode or one-shot mode.
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Acked-by: Philippe Ombredanne <pombredanne@xxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1515418139-23276-8-git-send-email-daniel.lezcano@xxxxxxxxxx
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
drivers/clocksource/Kconfig | 7 ++
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-sprd.c | 159 +++++++++++++++++++++++++++++++++++++++
3 files changed, 167 insertions(+)
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index c729a88..0359812 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -441,6 +441,13 @@ config MTK_TIMER
help
Support for Mediatek timer driver.
+config SPRD_TIMER
+ bool "Spreadtrum timer driver" if COMPILE_TEST
+ depends on HAS_IOMEM
+ select TIMER_OF
+ help
+ Enables support for the Spreadtrum timer driver.
+
config SYS_SUPPORTS_SH_MTU2
bool
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 72711f1..d6dec44 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -54,6 +54,7 @@ obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o
obj-$(CONFIG_CLKSRC_NPS) += timer-nps.o
obj-$(CONFIG_OXNAS_RPS_TIMER) += timer-oxnas-rps.o
obj-$(CONFIG_OWL_TIMER) += owl-timer.o
+obj-$(CONFIG_SPRD_TIMER) += timer-sprd.o
obj-$(CONFIG_ARC_TIMERS) += arc_timer.o
obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
diff --git a/drivers/clocksource/timer-sprd.c b/drivers/clocksource/timer-sprd.c
new file mode 100644
index 0000000..ef9ebea
--- /dev/null
+++ b/drivers/clocksource/timer-sprd.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Spreadtrum Communications Inc.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+
+#include "timer-of.h"
+
+#define TIMER_NAME "sprd_timer"
+
+#define TIMER_LOAD_LO 0x0
+#define TIMER_LOAD_HI 0x4
+#define TIMER_VALUE_LO 0x8
+#define TIMER_VALUE_HI 0xc
+
+#define TIMER_CTL 0x10
+#define TIMER_CTL_PERIOD_MODE BIT(0)
+#define TIMER_CTL_ENABLE BIT(1)
+#define TIMER_CTL_64BIT_WIDTH BIT(16)
+
+#define TIMER_INT 0x14
+#define TIMER_INT_EN BIT(0)
+#define TIMER_INT_RAW_STS BIT(1)
+#define TIMER_INT_MASK_STS BIT(2)
+#define TIMER_INT_CLR BIT(3)
+
+#define TIMER_VALUE_SHDW_LO 0x18
+#define TIMER_VALUE_SHDW_HI 0x1c
+
+#define TIMER_VALUE_LO_MASK GENMASK(31, 0)
+
+static void sprd_timer_enable(void __iomem *base, u32 flag)
+{
+ u32 val = readl_relaxed(base + TIMER_CTL);
+
+ val |= TIMER_CTL_ENABLE;
+ if (flag & TIMER_CTL_64BIT_WIDTH)
+ val |= TIMER_CTL_64BIT_WIDTH;
+ else
+ val &= ~TIMER_CTL_64BIT_WIDTH;
+
+ if (flag & TIMER_CTL_PERIOD_MODE)
+ val |= TIMER_CTL_PERIOD_MODE;
+ else
+ val &= ~TIMER_CTL_PERIOD_MODE;
+
+ writel_relaxed(val, base + TIMER_CTL);
+}
+
+static void sprd_timer_disable(void __iomem *base)
+{
+ u32 val = readl_relaxed(base + TIMER_CTL);
+
+ val &= ~TIMER_CTL_ENABLE;
+ writel_relaxed(val, base + TIMER_CTL);
+}
+
+static void sprd_timer_update_counter(void __iomem *base, unsigned long cycles)
+{
+ writel_relaxed(cycles & TIMER_VALUE_LO_MASK, base + TIMER_LOAD_LO);
+ writel_relaxed(0, base + TIMER_LOAD_HI);
+}
+
+static void sprd_timer_enable_interrupt(void __iomem *base)
+{
+ writel_relaxed(TIMER_INT_EN, base + TIMER_INT);
+}
+
+static void sprd_timer_clear_interrupt(void __iomem *base)
+{
+ u32 val = readl_relaxed(base + TIMER_INT);
+
+ val |= TIMER_INT_CLR;
+ writel_relaxed(val, base + TIMER_INT);
+}
+
+static int sprd_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *ce)
+{
+ struct timer_of *to = to_timer_of(ce);
+
+ sprd_timer_disable(timer_of_base(to));
+ sprd_timer_update_counter(timer_of_base(to), cycles);
+ sprd_timer_enable(timer_of_base(to), 0);
+
+ return 0;
+}
+
+static int sprd_timer_set_periodic(struct clock_event_device *ce)
+{
+ struct timer_of *to = to_timer_of(ce);
+
+ sprd_timer_disable(timer_of_base(to));
+ sprd_timer_update_counter(timer_of_base(to), timer_of_period(to));
+ sprd_timer_enable(timer_of_base(to), TIMER_CTL_PERIOD_MODE);
+
+ return 0;
+}
+
+static int sprd_timer_shutdown(struct clock_event_device *ce)
+{
+ struct timer_of *to = to_timer_of(ce);
+
+ sprd_timer_disable(timer_of_base(to));
+ return 0;
+}
+
+static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *ce = (struct clock_event_device *)dev_id;
+ struct timer_of *to = to_timer_of(ce);
+
+ sprd_timer_clear_interrupt(timer_of_base(to));
+
+ if (clockevent_state_oneshot(ce))
+ sprd_timer_disable(timer_of_base(to));
+
+ ce->event_handler(ce);
+ return IRQ_HANDLED;
+}
+
+static struct timer_of to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+ .clkevt = {
+ .name = TIMER_NAME,
+ .rating = 300,
+ .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = sprd_timer_shutdown,
+ .set_state_periodic = sprd_timer_set_periodic,
+ .set_next_event = sprd_timer_set_next_event,
+ .cpumask = cpu_possible_mask,
+ },
+
+ .of_irq = {
+ .handler = sprd_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ },
+};
+
+static int __init sprd_timer_init(struct device_node *np)
+{
+ int ret;
+
+ ret = timer_of_init(np, &to);
+ if (ret)
+ return ret;
+
+ sprd_timer_enable_interrupt(timer_of_base(&to));
+ clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+ 1, UINT_MAX);
+
+ return 0;
+}
+
+TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);