Re: [PATCH v2 06/15] clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCs

From: Sugaya, Taichi
Date: Thu Feb 14 2019 - 21:26:36 EST


Hi, Daniel

On 2019/02/15 0:22, Daniel Lezcano wrote:
On 08/02/2019 13:26, Sugaya Taichi wrote:
Add timer driver for Milbeaut SoCs series.

The timer has two 32-bit width down counters, one of which is configured
as a clockevent device and the other is configured as a clock source.

Signed-off-by: Sugaya Taichi <sugaya.taichi@xxxxxxxxxxxxx>

Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>


Thank you!

---
drivers/clocksource/Kconfig | 9 ++
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-milbeaut.c | 161 +++++++++++++++++++++++++++++++++++
3 files changed, 171 insertions(+)
create mode 100644 drivers/clocksource/timer-milbeaut.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index a9e26f6..9101b8f 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -634,4 +634,13 @@ config GX6605S_TIMER
help
This option enables support for gx6605s SOC's timer.
+config MILBEAUT_TIMER
+ bool "Milbeaut timer driver" if COMPILE_TEST
+ depends on OF
+ depends on ARM
+ select TIMER_OF
+ select CLKSRC_MMIO
+ help
+ Enables the support for Milbeaut timer driver.
+
endmenu
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index cdd210f..6f2543b 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -55,6 +55,7 @@ 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) += timer-owl.o
+obj-$(CONFIG_MILBEAUT_TIMER) += timer-milbeaut.o
obj-$(CONFIG_SPRD_TIMER) += timer-sprd.o
obj-$(CONFIG_NPCM7XX_TIMER) += timer-npcm7xx.o
obj-$(CONFIG_RDA_TIMER) += timer-rda.o
diff --git a/drivers/clocksource/timer-milbeaut.c b/drivers/clocksource/timer-milbeaut.c
new file mode 100644
index 0000000..f2019a8
--- /dev/null
+++ b/drivers/clocksource/timer-milbeaut.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Socionext Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include "timer-of.h"
+
+#define MLB_TMR_TMCSR_OFS 0x0
+#define MLB_TMR_TMR_OFS 0x4
+#define MLB_TMR_TMRLR1_OFS 0x8
+#define MLB_TMR_TMRLR2_OFS 0xc
+#define MLB_TMR_REGSZPCH 0x10
+
+#define MLB_TMR_TMCSR_OUTL BIT(5)
+#define MLB_TMR_TMCSR_RELD BIT(4)
+#define MLB_TMR_TMCSR_INTE BIT(3)
+#define MLB_TMR_TMCSR_UF BIT(2)
+#define MLB_TMR_TMCSR_CNTE BIT(1)
+#define MLB_TMR_TMCSR_TRG BIT(0)
+
+#define MLB_TMR_TMCSR_CSL_DIV2 0
+#define MLB_TMR_DIV_CNT 2
+
+#define MLB_TMR_SRC_CH (1)
+#define MLB_TMR_EVT_CH (0)
+
+#define MLB_TMR_SRC_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_SRC_CH)
+#define MLB_TMR_EVT_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_EVT_CH)
+
+#define MLB_TMR_SRC_TMCSR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMCSR_OFS)
+#define MLB_TMR_SRC_TMR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMR_OFS)
+#define MLB_TMR_SRC_TMRLR1_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR1_OFS)
+#define MLB_TMR_SRC_TMRLR2_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR2_OFS)
+
+#define MLB_TMR_EVT_TMCSR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMCSR_OFS)
+#define MLB_TMR_EVT_TMR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMR_OFS)
+#define MLB_TMR_EVT_TMRLR1_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR1_OFS)
+#define MLB_TMR_EVT_TMRLR2_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR2_OFS)
+
+#define MLB_TIMER_RATING 500
+
+static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *clk = dev_id;
+ struct timer_of *to = to_timer_of(clk);
+ u32 val;
+
+ val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+ val &= ~MLB_TMR_TMCSR_UF;
+ writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+
+ clk->event_handler(clk);
+
+ return IRQ_HANDLED;
+}
+
+static int mlb_set_state_periodic(struct clock_event_device *clk)
+{
+ struct timer_of *to = to_timer_of(clk);
+ u32 val = MLB_TMR_TMCSR_CSL_DIV2;
+
+ writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+
+ writel_relaxed(to->of_clk.period, timer_of_base(to) +
+ MLB_TMR_EVT_TMRLR1_OFS);
+ val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE |
+ MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE;
+ writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+ return 0;
+}
+
+static int mlb_set_state_oneshot(struct clock_event_device *clk)
+{
+ struct timer_of *to = to_timer_of(clk);
+ u32 val = MLB_TMR_TMCSR_CSL_DIV2;
+
+ writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+ return 0;
+}
+
+static int mlb_clkevt_next_event(unsigned long event,
+ struct clock_event_device *clk)
+{
+ struct timer_of *to = to_timer_of(clk);
+
+ writel_relaxed(event, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS);
+ writel_relaxed(MLB_TMR_TMCSR_CSL_DIV2 |
+ MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_INTE |
+ MLB_TMR_TMCSR_TRG, timer_of_base(to) +
+ MLB_TMR_EVT_TMCSR_OFS);
+ return 0;
+}
+
+static int mlb_config_clock_source(struct timer_of *to)
+{
+ writel_relaxed(0, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS);
+ writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMR_OFS);
+ writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR1_OFS);
+ writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR2_OFS);
+ writel_relaxed(BIT(4) | BIT(1) | BIT(0), timer_of_base(to) +
+ MLB_TMR_SRC_TMCSR_OFS);
+ return 0;
+}
+
+static int mlb_config_clock_event(struct timer_of *to)
+{
+ writel_relaxed(0, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+ return 0;
+}
+
+static struct timer_of to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+ .clkevt = {
+ .name = "mlb-clkevt",
+ .rating = MLB_TIMER_RATING,
+ .cpumask = cpu_possible_mask,
+ .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_oneshot = mlb_set_state_oneshot,
+ .set_state_periodic = mlb_set_state_periodic,
+ .set_next_event = mlb_clkevt_next_event,
+ },
+
+ .of_irq = {
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = mlb_timer_interrupt,
+ },
+};
+
+static u64 notrace mlb_timer_sched_read(void)
+{
+ return ~readl_relaxed(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS);
+}
+
+static int __init mlb_timer_init(struct device_node *node)
+{
+ int ret;
+ unsigned long rate;
+
+ ret = timer_of_init(node, &to);
+ if (ret)
+ return ret;
+
+ rate = timer_of_rate(&to) / MLB_TMR_DIV_CNT;
+ mlb_config_clock_source(&to);
+ clocksource_mmio_init(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS,
+ node->name, rate, MLB_TIMER_RATING, 32,
+ clocksource_mmio_readl_down);
+ sched_clock_register(mlb_timer_sched_read, 32, rate);
+ mlb_config_clock_event(&to);
+ clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), 15,
+ 0xffffffff);
+ return 0;
+}
+TIMER_OF_DECLARE(mlb_peritimer, "socionext,milbeaut-timer",
+ mlb_timer_init);