Re: [PATCHv3 3/3] clocksource: Add Freescale FlexTimer Module (FTM) timer support

From: Daniel Lezcano
Date: Fri May 16 2014 - 09:00:56 EST


On 04/29/2014 04:18 AM, Xiubo Li wrote:
The Freescale FlexTimer Module time reference is a 16-bit counter
that can be used as an unsigned or signed increase counter.

CNTIN defines the starting value of the count and MOD defines the
final value of the count. The value of CNTIN is loaded into the FTM
counter, and the counter increments until the value of MOD is reached,
at which point the counter is reloaded with the value of CNTIN. That's
also when an overflow interrupt will be generated.

Here using the 'evt' prefix or postfix as clock event device and
the 'src' as clock source device.

Signed-off-by: Xiubo Li <Li.Xiubo@xxxxxxxxxxxxx>
Cc: Shawn Guo <shawn.guo@xxxxxxxxxx>
Cc: Jingchang Lu <b35083@xxxxxxxxxxxxx>
---
drivers/clocksource/Kconfig | 5 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/fsl_ftm_timer.c | 344 ++++++++++++++++++++++++++++++++++++
3 files changed, 350 insertions(+)
create mode 100644 drivers/clocksource/fsl_ftm_timer.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index cd6950f..28321c5 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -136,6 +136,11 @@ config CLKSRC_SAMSUNG_PWM
for all devicetree enabled platforms. This driver will be
needed only on systems that do not have the Exynos MCT available.

+config FSL_FTM_TIMER
+ bool
+ help
+ Support for Freescale FlexTimer Module (FTM) timer.
+
config VF_PIT_TIMER
bool
help
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index c7ca50a..ce0a967 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o
obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o
obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o
obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o
+obj-$(CONFIG_FSL_FTM_TIMER) += fsl_ftm_timer.o
obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o

obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
diff --git a/drivers/clocksource/fsl_ftm_timer.c b/drivers/clocksource/fsl_ftm_timer.c
new file mode 100644
index 0000000..7f6246a
--- /dev/null
+++ b/drivers/clocksource/fsl_ftm_timer.c
@@ -0,0 +1,344 @@
+/*
+ * Freescale FlexTimer Module (FTM) timer driver.
+ *
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#define FTM_SC 0x00
+#define FTM_SC_CLK_SHIFT 3
+#define FTM_SC_CLK_MASK (0x3 << FTM_SC_CLK_SHIFT)
+#define FTM_SC_CLK(c) ((c) << FTM_SC_CLK_SHIFT)
+#define FTM_SC_PS_MASK 0x7
+#define FTM_SC_TOIE BIT(6)
+#define FTM_SC_TOF BIT(7)
+
+#define FTM_CNT 0x04
+#define FTM_MOD 0x08
+#define FTM_CNTIN 0x4C
+
+static void __iomem *clksrc_base;
+static void __iomem *clkevt_base;
+static unsigned long peroidic_cyc;

peroidic_cyc ? Did you mean periodic_cyc ? :)



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