Re: [PATCH 05/14] clocksource/drivers/timer-milbeaut: Add Milbeaut M10V timer

From: Sugaya, Taichi
Date: Wed Nov 21 2018 - 21:24:20 EST

Hi Daniel

Thank you for your comments.

On 2018/11/21 19:08, Daniel Lezcano wrote:
Hi Sugaya,


On 19/11/2018 02:01, Sugaya Taichi wrote:
Add Milbeaut M10V timer using 32bit timer in peripheral.
Give a better description of the timer as it is new timer introduced.

I got it. Add more description.


Signed-off-by: Sugaya Taichi <sugaya.taichi@xxxxxxxxxxxxx>
---
drivers/clocksource/Kconfig | 8 +++
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-m10v.c | 146 +++++++++++++++++++++++++++++++++++++++
3 files changed, 155 insertions(+)
create mode 100644 drivers/clocksource/timer-m10v.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 55c77e4..a278d72 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -638,4 +638,12 @@ config GX6605S_TIMER
help
This option enables support for gx6605s SOC's timer.
+config M10V_TIMER
+ bool "Milbeaut M10V timer driver" if COMPILE_TEST
+ depends on OF
+ depends on ARM
+ select TIMER_OF
+ help
+ Enables the support for Milbeaut M10V timer driver.
+
endmenu
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index dd91381..8e908b4 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-$(CONFIG_M10V_TIMER) += timer-m10v.o
obj-$(CONFIG_SPRD_TIMER) += timer-sprd.o
obj-$(CONFIG_NPCM7XX_TIMER) += timer-npcm7xx.o
diff --git a/drivers/clocksource/timer-m10v.c b/drivers/clocksource/timer-m10v.c
new file mode 100644
index 0000000..ff97c23
--- /dev/null
+++ b/drivers/clocksource/timer-m10v.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Socionext Inc.
+ */
+
+#include <linux/clk.h>
------->

+#include <linux/clockchips.h>
It is included from timer-of.h

<-------

OK. Remove it.



+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
------->

+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
Those are not needed IMO.

<---------

OK, remove these.




+#include "timer-of.h"
+
+#define FSL_TMR_TMCSR_OFS 0x0
+#define FSL_TMR_TMR_OFS 0x4
+#define FSL_TMR_TMRLR1_OFS 0x8
+#define FSL_TMR_TMRLR2_OFS 0xc
+#define FSL_RMT_REGSZPCH 0x10
+
+#define FSL_TMR_TMCSR_OUTL BIT(5)
+#define FSL_TMR_TMCSR_RELD BIT(4)
+#define FSL_TMR_TMCSR_INTE BIT(3)
+#define FSL_TMR_TMCSR_UF BIT(2)
+#define FSL_TMR_TMCSR_CNTE BIT(1)
+#define FSL_TMR_TMCSR_TRG BIT(0)
+
+#define FSL_TMR_TMCSR_CSL_DIV2 0
+#define FSL_TMR_TMCSR_CSL BIT(10)
+
+#define M10V_TIMER_RATING 500
+
+static irqreturn_t m10v_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) + FSL_TMR_TMCSR_OFS);
+ val &= ~FSL_TMR_TMCSR_UF;
+ writel_relaxed(val, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+
+ clk->event_handler(clk);
+
+ return IRQ_HANDLED;
+}
+
+static int m10v_set_state_periodic(struct clock_event_device *clk)
+{
+ struct timer_of *to = to_timer_of(clk);
+ u32 val = (FSL_TMR_TMCSR_CSL_DIV2 * FSL_TMR_TMCSR_CSL);
FSL_TMR_TMCSR_CSL_DIV2 is zero, so val is always zero.
Ah, yes.
The FSL_TMR_TMCSR is the 10th bit field of the register, so it would be better
to bit-shift.
I will use it as simply 0.


+ writel_relaxed(val, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+
+ writel_relaxed(to->of_clk.period, timer_of_base(to) +
+ FSL_TMR_TMRLR1_OFS);
+ val |= FSL_TMR_TMCSR_RELD | FSL_TMR_TMCSR_CNTE |
+ FSL_TMR_TMCSR_TRG | FSL_TMR_TMCSR_INTE;
+ writel_relaxed(val, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+ return 0;
+}
+
+static int m10v_set_state_oneshot(struct clock_event_device *clk)
+{
+ struct timer_of *to = to_timer_of(clk);
+ u32 val = (FSL_TMR_TMCSR_CSL_DIV2 * FSL_TMR_TMCSR_CSL);
+
+ writel_relaxed(val, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+ return 0;
+}
+
+static int m10v_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) + FSL_TMR_TMRLR1_OFS);
+ writel_relaxed((FSL_TMR_TMCSR_CSL_DIV2 * FSL_TMR_TMCSR_CSL) |
Same comment here.

I got it.


+ FSL_TMR_TMCSR_CNTE | FSL_TMR_TMCSR_INTE |
+ FSL_TMR_TMCSR_TRG, timer_of_base(to) +
+ FSL_TMR_TMCSR_OFS);
+ return 0;
+}
+
+static int m10v_config_clock_source(struct timer_of *to)
+{
+ writel_relaxed(0, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+ writel_relaxed(~0, timer_of_base(to) + FSL_TMR_TMR_OFS);
+ writel_relaxed(~0, timer_of_base(to) + FSL_TMR_TMRLR1_OFS);
+ writel_relaxed(~0, timer_of_base(to) + FSL_TMR_TMRLR2_OFS);
+ writel_relaxed(BIT(4) | BIT(1) | BIT(0), timer_of_base(to) +
+ FSL_TMR_TMCSR_OFS);
+ return 0;
+}
+
+static int m10v_config_clock_event(struct timer_of *to)
+{
+ writel_relaxed(0, timer_of_base(to) + FSL_TMR_TMCSR_OFS);
+ return 0;
+}
+
+static struct timer_of to = {
+ .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+ .clkevt = {
+ .name = "m10v-clkevt",
+ .rating = M10V_TIMER_RATING,
+ .cpumask = cpu_possible_mask,
+ },
+
+ .of_irq = {
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ },
+};
+
+static int __init m10v_timer_init(struct device_node *node)
+{
+ int ret;
+
+ to.clkevt.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT;
+ to.clkevt.set_state_oneshot = m10v_set_state_oneshot;
+ to.clkevt.set_state_periodic = m10v_set_state_periodic;
+ to.clkevt.set_next_event = m10v_clkevt_next_event;
+ to.of_irq.handler = m10v_timer_interrupt;
Move the initialization in the timer_of structure above.

Okay.



+ ret = timer_of_init(node, &to);
+ if (ret)
+ goto err;
You should return directly, rollback is done in the timer_of_init().

OK.



+
+ m10v_config_clock_source(&to);
+ clocksource_mmio_init(timer_of_base(&to) + FSL_TMR_TMR_OFS,
+ node->name, timer_of_rate(&to), M10V_TIMER_RATING, 32,
+ clocksource_mmio_readl_down);
May be you can add the sched_clock also ?

OK. Add it and confirm.


Thanks
Sugaya Taichi



+ m10v_config_clock_event(&to);
+ clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+ 15, 0xffffffff);
+
+ return 0;
+err:
+ timer_of_cleanup(&to);
+ return ret;
+}
+TIMER_OF_DECLARE(m10v_peritimer, "socionext,milbeaut-m10v-timer",
+ m10v_timer_init);