[PATCH 6/9] arm: twr-k70f120m: clock source drivers for Kinetis SoC

Paul Osmialowski
2015-06-23T21:19:44Z

Based on K70P256M150SF3RM.pdf

Signed-off-by: Paul Osmialowski <pawelo-rhuoMcPwk82rDJvtcaxF/A@public.gmane.org>
---
.../devicetree/bindings/clock/kinetis-clock.txt | 25 ++
.../bindings/timer/fsl,kinetis-pit-timer.txt | 18 ++
arch/arm/Kconfig | 1 +
arch/arm/boot/dts/kinetis-twr-k70f120m.dts | 4 +
arch/arm/boot/dts/kinetis.dtsi | 50 ++++
arch/arm/mach-kinetis/include/mach/power.h | 83 ++++++
drivers/clk/Makefile | 1 +
drivers/clk/clk-kinetis.c | 226 ++++++++++++++++
drivers/clocksource/Kconfig | 5 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-kinetis.c | 294 +++++++++++++++++++++
include/dt-bindings/clock/kinetis-mcg.h | 10 +
12 files changed, 718 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/kinetis-clock.txt
create mode 100644 Documentation/devicetree/bindings/timer/fsl,kinetis-pit-timer.txt
create mode 100644 arch/arm/mach-kinetis/include/mach/power.h
create mode 100644 drivers/clk/clk-kinetis.c
create mode 100644 drivers/clocksource/timer-kinetis.c
create mode 100644 include/dt-bindings/clock/kinetis-mcg.h

diff --git a/Documentation/devicetree/bindings/clock/kinetis-clock.txt b/Documentation/devicetree/bindings/clock/kinetis-clock.txt
new file mode 100644
index 0000000..9c9c4fe
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/kinetis-clock.txt
@@ -0,0 +1,25 @@
+* Clock bindings for Freescale Kinetis SoC
+
+Required properties:
+- compatible: Should be "fsl,kinetis-cmu".
+- reg: Address and length of the register set.
+- #clock-cells: Should be <1>.
+
+Example:
+
+mcg: cmu@40064000 {
+ compatible = "fsl,kinetis-cmu";
+ reg = <0x40064000 0x14>;
+ #clock-cells = <1>;
+};
+
+uart1: serial@4006b000 {
+ compatible = "fsl,kinetis-lpuart";
+ reg = <0x4006b000 0x1000>;
+ interrupts = <47>, <48>;
+ interrupt-names = "uart-stat", "uart-err";
+ clocks = <&mcg CLOCK_UART1>;
+ clock-names = "ipg";
+ dmas = <&edma 0 4>;
+ dma-names = "rx";
+};
diff --git a/Documentation/devicetree/bindings/timer/fsl,kinetis-pit-timer.txt b/Documentation/devicetree/bindings/timer/fsl,kinetis-pit-timer.txt
new file mode 100644
index 0000000..49dddf6
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/fsl,kinetis-pit-timer.txt
@@ -0,0 +1,18 @@
+Freescale Kinetis SoC Periodic Interrupt Timer (PIT)
+
+Required properties:
+
+- compatible: Should be "fsl,kinetis-pit-timer".
+- reg: Specifies base physical address and size of the register sets for the
+ clock event device.
+- interrupts: Should be the clock event device interrupt.
+- clocks: The clocks provided by the SoC to drive the timer.
+
+Example:
+
+pit0: timer@40037100 {
+ compatible = "fsl,kinetis-pit-timer";
+ reg = <0x40037100 0x10>;
+ interrupts = <68>;
+ clocks = <&mcg CLOCK_PIT>;
+};
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 747cdea..8630aff 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -979,6 +979,7 @@ config ARCH_KINETIS
select CPU_CORTEXM3
select ARM_CPU_IDLE_QUIRKS
select ARMV7M_SYSTICK
+ select CLKSRC_KINETIS
select ZLIB_INFLATE_STACK_SAVING if ZLIB_INFLATE
help
This enables support for the Freescale Kinetis MCUs
diff --git a/arch/arm/boot/dts/kinetis-twr-k70f120m.dts b/arch/arm/boot/dts/kinetis-twr-k70f120m.dts
index edccf37..a6efc29 100644
--- a/arch/arm/boot/dts/kinetis-twr-k70f120m.dts
+++ b/arch/arm/boot/dts/kinetis-twr-k70f120m.dts
@@ -14,3 +14,7 @@
reg = <0x8000000 0x8000000>;
};
};
+
+&pit0 {
+ status = "ok";
+};
diff --git a/arch/arm/boot/dts/kinetis.dtsi b/arch/arm/boot/dts/kinetis.dtsi
index 93d2a8a..770760f 100644
--- a/arch/arm/boot/dts/kinetis.dtsi
+++ b/arch/arm/boot/dts/kinetis.dtsi
@@ -3,3 +3,53 @@
*
*/
#include "armv7-m.dtsi"
+#include "dt-bindings/clock/kinetis-mcg.h"
+
+/ {
+ aliases {
+ pit0 = &pit0;
+ pit1 = &pit1;
+ pit2 = &pit2;
+ pit3 = &pit3;
+ };
+
+ soc {
+ pit0: timer@40037100 {
+ compatible = "fsl,kinetis-pit-timer";
+ reg = <0x40037100 0x10>;
+ interrupts = <68>;
+ clocks = <&mcg CLOCK_PIT>;
+ status = "disabled";
+ };
+
+ pit1: timer@40037110 {
+ compatible = "fsl,kinetis-pit-timer";
+ reg = <0x40037110 0x10>;
+ interrupts = <69>;
+ clocks = <&mcg CLOCK_PIT>;
+ status = "disabled";
+ };
+
+ pit2: timer@40037120 {
+ compatible = "fsl,kinetis-pit-timer";
+ reg = <0x40037120 0x10>;
+ interrupts = <70>;
+ clocks = <&mcg CLOCK_PIT>;
+ status = "disabled";
+ };
+
+ pit3: timer@40037130 {
+ compatible = "fsl,kinetis-pit-timer";
+ reg = <0x40037130 0x10>;
+ interrupts = <71>;
+ clocks = <&mcg CLOCK_PIT>;
+ status = "disabled";
+ };
+
+ mcg: cmu@40064000 {
+ compatible = "fsl,kinetis-cmu";
+ reg = <0x40064000 0x14>;
+ #clock-cells = <1>;
+ };
+ };
+};
diff --git a/arch/arm/mach-kinetis/include/mach/power.h b/arch/arm/mach-kinetis/include/mach/power.h
new file mode 100644
index 0000000..e67bd4e
--- /dev/null
+++ b/arch/arm/mach-kinetis/include/mach/power.h
@@ -0,0 +1,83 @@
+/*
+ * (C) Copyright 2011, 2012
+ * Emcraft Systems, <www.emcraft.com>
+ * Alexander Potashev <aspotashev-qv+LCo8X3VpBDgjK7y7TUQ@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#ifndef _MACH_KINETIS_POWER_H
+#define _MACH_KINETIS_POWER_H
+
+/*
+ * Pack the SIM_SCGC[] register index and the bit index in that register into
+ * a single word. This is similar to the implementation of `dev_t` in
+ * the Linux kernel with its `MAJOR(dev)`, `MINOR(dev)` and
+ * `MKDEV(major,minor)` macros.
+ *
+ * This is useful when you want to have an array of `kinetis_clock_gate_t`s:
+ * you do not have to use a 2-dimensional array or a real structure.
+ */
+typedef u32 kinetis_clock_gate_t;
+#define KINETIS_CG_IDX_BITS 16
+#define KINETIS_CG_IDX_MASK ((1U << KINETIS_CG_IDX_BITS) - 1)
+/*
+ * Extract the register number and the bit index from a `kinetis_clock_gate_t`.
+ * The register number counts from 0,
+ * i.e. the register number for SIM_SCGC7 is 6.
+ */
+#define KINETIS_CG_REG(gate) ((unsigned int) ((gate) >> KINETIS_CG_IDX_BITS))
+#define KINETIS_CG_IDX(gate) ((unsigned int) ((gate) & KINETIS_CG_IDX_MASK))
+/*
+ * Build a `kinetis_clock_gate_t` from a register number and a bit index
+ */
+#define KINETIS_MKCG(reg, idx) \
+ (((kinetis_clock_gate_t)(reg) << KINETIS_CG_IDX_BITS) | \
+ (kinetis_clock_gate_t)(idx))
+
+/*
+ * Clock gates for the modules inside the MCU
+ */
+/* UARTs */
+#define KINETIS_CG_UART0 KINETIS_MKCG(3, 10) /* SIM_SCGC4[10] */
+#define KINETIS_CG_UART1 KINETIS_MKCG(3, 11) /* SIM_SCGC4[11] */
+#define KINETIS_CG_UART2 KINETIS_MKCG(3, 12) /* SIM_SCGC4[12] */
+#define KINETIS_CG_UART3 KINETIS_MKCG(3, 13) /* SIM_SCGC4[13] */
+#define KINETIS_CG_UART4 KINETIS_MKCG(0, 10) /* SIM_SCGC1[10] */
+#define KINETIS_CG_UART5 KINETIS_MKCG(0, 11) /* SIM_SCGC1[11] */
+/* Ports */
+#define KINETIS_CG_PORTA KINETIS_MKCG(4, 9) /* SIM_SCGC5[9] */
+#define KINETIS_CG_PORTB KINETIS_MKCG(4, 10) /* SIM_SCGC5[10] */
+#define KINETIS_CG_PORTC KINETIS_MKCG(4, 11) /* SIM_SCGC5[11] */
+#define KINETIS_CG_PORTD KINETIS_MKCG(4, 12) /* SIM_SCGC5[12] */
+#define KINETIS_CG_PORTE KINETIS_MKCG(4, 13) /* SIM_SCGC5[13] */
+#define KINETIS_CG_PORTF KINETIS_MKCG(4, 14) /* SIM_SCGC5[14] */
+/* ENET */
+#define KINETIS_CG_ENET KINETIS_MKCG(1, 0) /* SIM_SCGC2[0] */
+/* Periodic Interrupt Timer (PIT) */
+#define KINETIS_CG_PIT KINETIS_MKCG(5, 23) /* SIM_SCGC6[23] */
+/* LCD Controller */
+#define KINETIS_CG_LCDC KINETIS_MKCG(2, 22) /* SIM_SCGC3[22] */
+/* DMA controller and DMA request multiplexer */
+#define KINETIS_CG_DMA KINETIS_MKCG(6, 1) /* SIM_SCGC7[1] */
+#define KINETIS_CG_DMAMUX0 KINETIS_MKCG(5, 1) /* SIM_SCGC6[1] */
+#define KINETIS_CG_DMAMUX1 KINETIS_MKCG(5, 2) /* SIM_SCGC6[2] */
+/* USB High Speed */
+#define KINETIS_CG_USBHS KINETIS_MKCG(5, 20) /* SIM_SCGC6[20] */
+/* USB Full Speed */
+#define KINETIS_CG_USBFS KINETIS_MKCG(3, 18) /* SIM_SCGC4[18] */
+/* ADC modules */
+#define KINETIS_CG_ADC0 KINETIS_MKCG(5, 27) /* SIM_SCGC6[27] */
+#define KINETIS_CG_ADC1 KINETIS_MKCG(2, 27) /* SIM_SCGC3[27] */
+#define KINETIS_CG_ADC2 KINETIS_MKCG(5, 28) /* SIM_SCGC6[28] */
+#define KINETIS_CG_ADC3 KINETIS_MKCG(2, 28) /* SIM_SCGC3[28] */
+/* ESDHC */
+#define KINETIS_CG_ESDHC KINETIS_MKCG(2, 17) /* SIM_SCGC3[17] */
+/* SPI */
+#define KINETIS_CG_SPI0 KINETIS_MKCG(5, 12) /* SIM_SCGC6[12] */
+#define KINETIS_CG_SPI1 KINETIS_MKCG(5, 13) /* SIM_SCGC6[13] */
+#define KINETIS_CG_SPI2 KINETIS_MKCG(2, 12) /* SIM_SCGC3[12] */
+
+#endif /*_MACH_KINETIS_POWER_H */
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index b241c17..58718ed 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_COMMON_CLK_CDCE706) += clk-cdce706.o
obj-$(CONFIG_ARCH_CLPS711X) += clk-clps711x.o
obj-$(CONFIG_ARCH_EFM32) += clk-efm32gg.o
obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o
+obj-$(CONFIG_ARCH_KINETIS) += clk-kinetis.o
obj-$(CONFIG_MACH_LOONGSON32) += clk-ls1x.o
obj-$(CONFIG_COMMON_CLK_MAX_GEN) += clk-max-gen.o
obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
diff --git a/drivers/clk/clk-kinetis.c b/drivers/clk/clk-kinetis.c
new file mode 100644
index 0000000..dea1054
--- /dev/null
+++ b/drivers/clk/clk-kinetis.c
@@ -0,0 +1,226 @@
+/*
+ * clk-kinetis.c - Clock driver for Kinetis K70 MCG
+ *
+ * Based on legacy pre-OF code by Alexander Potashev <aspotashev-qv+LCo8X3VpBDgjK7y7TUQ@public.gmane.org>
+ *
+ * Copyright (C) 2015 Paul Osmialowski <pawelo-rhuoMcPwk82rDJvtcaxF/A@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/err.h>
+#include <mach/kinetis.h>
+#include <mach/power.h>
+
+#include <dt-bindings/clock/kinetis-mcg.h>
+
+/*
+ * Frequencies on OSC0 (EXTAL0/XTAL0) and OSC1 (EXTAL1/XTAL1)
+ *
+ * These frequencies should be set to the same values as in U-Boot.
+ */
+#define KINETIS_OSC0_RATE 50000000 /* 50 MHz */
+#define KINETIS_OSC1_RATE 12000000 /* 12 MHz */
+
+/*
+ * MCG Control 5 Register
+ */
+/* PLL External Reference Divider */
+#define KINETIS_MCG_C5_PRDIV_BITS 0
+#define KINETIS_MCG_C5_PRDIV_MSK \
+ (((1 << 3) - 1) << KINETIS_MCG_C5_PRDIV_BITS)
+/* PLL Stop Enable */
+#define KINETIS_MCG_C5_PLLSTEN_MSK (1 << 5)
+/* PLL Clock Enable */
+#define KINETIS_MCG_C5_PLLCLKEN_MSK (1 << 6)
+/* PLL External Reference Select (for K70@120MHz) */
+#define KINETIS_MCG_C5_PLLREFSEL_BIT 7
+#define KINETIS_MCG_C5_PLLREFSEL_MSK (1 << KINETIS_MCG_C5_PLLREFSEL_BIT)
+/*
+ * MCG Control 6 Register
+ */
+/* VCO Divider */
+#define KINETIS_MCG_C6_VDIV_BITS 0
+#define KINETIS_MCG_C6_VDIV_MSK \
+ (((1 << 5) - 1) << KINETIS_MCG_C6_VDIV_BITS)
+/* PLL Select */
+#define KINETIS_MCG_C6_PLLS_MSK (1 << 6)
+/*
+ * MCG Control 11 Register
+ */
+/* PLL1 External Reference Divider */
+#define KINETIS_MCG_C11_PRDIV_BITS 0
+#define KINETIS_MCG_C11_PRDIV_MSK \
+ (((1 << 3) - 1) << KINETIS_MCG_C11_PRDIV_BITS)
+/* PLL Clock Select: PLL0 or PLL1 */
+#define KINETIS_MCG_C11_PLLCS_MSK (1 << 4)
+/* PLL1 Stop Enable */
+#define KINETIS_MCG_C11_PLLSTEN1_MSK (1 << 5)
+/* PLL1 Clock Enable */
+#define KINETIS_MCG_C11_PLLCLKEN1_MSK (1 << 6)
+/* PLL1 External Reference Select (for K70@120MHz) */
+#define KINETIS_MCG_C11_PLLREFSEL1_BIT 7
+#define KINETIS_MCG_C11_PLLREFSEL1_MSK (1 << KINETIS_MCG_C11_PLLREFSEL1_BIT)
+/*
+ * MCG Control 12 Register
+ */
+/* VCO1 Divider */
+#define KINETIS_MCG_C12_VDIV1_BITS 0
+#define KINETIS_MCG_C12_VDIV1_MSK \
+ (((1 << 5) - 1) << KINETIS_MCG_C12_VDIV1_BITS)
+
+/*
+ * Multipurpose Clock Generator (MCG) register map
+ *
+ * See Chapter 25 of the K70 Reference Manual
+ */
+struct kinetis_mcg_regs {
+ u8 c1; /* MCG Control 1 Register */
+ u8 c2; /* MCG Control 2 Register */
+ u8 c3; /* MCG Control 3 Register */
+ u8 c4; /* MCG Control 4 Register */
+ u8 c5; /* MCG Control 5 Register */
+ u8 c6; /* MCG Control 6 Register */
+ u8 status; /* MCG Status Register */
+ u8 rsv0;
+ u8 atc; /* MCG Auto Trim Control Register */
+ u8 rsv1;
+ u8 atcvh; /* MCG Auto Trim Compare Value High Register */
+ u8 atcvl; /* MCG Auto Trim Compare Value Low Register */
+ u8 c7; /* MCG Control 7 Register */
+ u8 c8; /* MCG Control 8 Register */
+ u8 rsv2;
+ u8 c10; /* MCG Control 10 Register */
+ u8 c11; /* MCG Control 11 Register */
+ u8 c12; /* MCG Control 12 Register */
+ u8 status2; /* MCG Status 2 Register */
+ u8 rsv3;
+};
+
+#define KINETIS_MCG_PTR(base, reg) \
+ (&(((struct kinetis_mcg_regs *)(base))->reg))
+#define KINETIS_MCG_RD(base, reg) readb_relaxed(KINETIS_MCG_PTR(base, reg))
+#define KINETIS_MCG_WR(base, reg, val) \
+ writeb_relaxed((val), KINETIS_MCG_PTR(base, reg))
+#define KINETIS_MCG_ISSET(base, reg, mask) \
+ (KINETIS_MCG_RD(base, reg) & (mask))
+
+static struct clk *clk[CLOCK_END];
+static struct clk_onecell_data clk_data = {
+ .clks = clk,
+ .clk_num = ARRAY_SIZE(clk),
+};
+
+static void __init kinetis_mcg_init(struct device_node *np)
+{
+ const int vco_div = 2;
+ const int vdiv_min = 16;
+ u32 clock_val[CLOCK_END];
+ int i;
+ void __iomem *base;
+ int pll_sel;
+ int osc_sel;
+ unsigned long mcgout;
+
+ for (i = 0; i < ARRAY_SIZE(clk); ++i)
+ clk[i] = ERR_PTR(-ENOENT);
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_warn("Failed to map address range for kinetis,mcg node\n");
+ return;
+ }
+
+ /*
+ * Check whether PLL0 or PLL1 is used for MCGOUTCLK
+ */
+ pll_sel = !!(KINETIS_MCG_ISSET(base, c11, KINETIS_MCG_C11_PLLCS_MSK));
+
+ /*
+ * Check whether OSC0 or OSC1 is used to source the main PLL
+ */
+ if (pll_sel)
+ osc_sel = !!(KINETIS_MCG_ISSET(base, c11,
+ KINETIS_MCG_C11_PLLREFSEL1_MSK));
+ else
+ osc_sel = !!(KINETIS_MCG_ISSET(base, c5,
+ KINETIS_MCG_C5_PLLREFSEL_MSK));
+
+ /*
+ * Start with the MCG input clock
+ */
+ mcgout = osc_sel ? KINETIS_OSC1_RATE : KINETIS_OSC0_RATE;
+
+ /*
+ * Apply dividers and multipliers of the selected PLL
+ */
+ if (pll_sel) {
+ /*
+ * PLL1 internal divider (PRDIV)
+ */
+ mcgout /= ((KINETIS_MCG_RD(base, c11) &
+ KINETIS_MCG_C11_PRDIV_MSK) >> KINETIS_MCG_C11_PRDIV_BITS) + 1;
+ /*
+ * PLL1 multiplication factor (VDIV)
+ */
+ mcgout *= ((KINETIS_MCG_RD(base, c12) &
+ KINETIS_MCG_C12_VDIV1_MSK) >> KINETIS_MCG_C12_VDIV1_BITS) +
+ vdiv_min;
+ } else {
+ /*
+ * PLL0 internal divider (PRDIV)
+ */
+ mcgout /= ((KINETIS_MCG_RD(base, c5) &
+ KINETIS_MCG_C5_PRDIV_MSK) >>
+ KINETIS_MCG_C5_PRDIV_BITS) + 1;
+ /*
+ * PLL0 multiplication factor (VDIV)
+ */
+ mcgout *= ((KINETIS_MCG_RD(base, c6) &
+ KINETIS_MCG_C6_VDIV_MSK) >>
+ KINETIS_MCG_C6_VDIV_BITS) + vdiv_min;
+ }
+
+ /*
+ * Apply the PLL output divider
+ */
+ mcgout /= vco_div;
+
+ clock_val[CLOCK_MCGOUTCLK] = mcgout;
+
+ clock_val[CLOCK_CCLK] = mcgout /
+ (((KINETIS_SIM_RD(clkdiv1) & KINETIS_SIM_CLKDIV1_OUTDIV1_MSK) >>
+ KINETIS_SIM_CLKDIV1_OUTDIV1_BITS) + 1);
+
+ /*
+ * Peripheral (bus) clock
+ */
+ clock_val[CLOCK_PCLK] = mcgout /
+ (((KINETIS_SIM_RD(clkdiv1) & KINETIS_SIM_CLKDIV1_OUTDIV2_MSK) >>
+ KINETIS_SIM_CLKDIV1_OUTDIV2_BITS) + 1);
+
+ clk[CLOCK_MCGOUTCLK] = clk_register_fixed_rate(NULL, "MCGOUTCLK",
+ NULL, CLK_IS_ROOT, clock_val[CLOCK_MCGOUTCLK]);
+
+ clk[CLOCK_CCLK] = clk_register_fixed_rate(NULL, "CCLK", "MCGOUTCLK",
+ 0, clock_val[CLOCK_CCLK]);
+
+ clk[CLOCK_PCLK] = clk_register_fixed_rate(NULL, "PCLK", "MCGOUTCLK",
+ 0, clock_val[CLOCK_PCLK]);
+
+ clk[CLOCK_PIT] = clk_register_gate(NULL, "PIT", "PCLK", 0,
+ KINETIS_SIM_PTR(scgc[KINETIS_CG_REG(KINETIS_CG_PIT)]),
+ KINETIS_CG_IDX(KINETIS_CG_PIT), 0, NULL);
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+CLK_OF_DECLARE(kinetis_mcg, "fsl,kinetis-cmu", kinetis_mcg_init);
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 0f1c77e..1d2ecde 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -106,6 +106,11 @@ config CLKSRC_EFM32
Support to use the timers of EFM32 SoCs as clock source and clock
event device.

+config CLKSRC_KINETIS
+ bool "Clocksource for Kinetis SoCs"
+ depends on OF && ARM && ARCH_KINETIS
+ select CLKSRC_OF
+
config CLKSRC_LPC32XX
bool
select CLKSRC_MMIO
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index f1ae0e7..6da77a8 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_ARCH_NSPIRE) += zevio-timer.o
obj-$(CONFIG_ARCH_BCM_MOBILE) += bcm_kona_timer.o
obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o
obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o
+obj-$(CONFIG_CLKSRC_KINETIS) += timer-kinetis.o
obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o
obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o
obj-$(CONFIG_CLKSRC_LPC32XX) += time-lpc32xx.o
diff --git a/drivers/clocksource/timer-kinetis.c b/drivers/clocksource/timer-kinetis.c
new file mode 100644
index 0000000..634f365
--- /dev/null
+++ b/drivers/clocksource/timer-kinetis.c
@@ -0,0 +1,294 @@
+/*
+ * timer-kinetis.c - Timer driver for Kinetis K70
+ *
+ * Based on legacy pre-OF code by Alexander Potashev <aspotashev-qv+LCo8X3VpBDgjK7y7TUQ@public.gmane.org>
+ *
+ * Copyright (C) 2015 Paul Osmialowski <pawelo-rhuoMcPwk82rDJvtcaxF/A@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/sched.h>
+#include <mach/kinetis.h>
+
+#define KINETIS_PIT_CHANNELS 4
+
+#define KINETIS_PIT0_IRQ 68
+#define KINETIS_PIT1_IRQ 69
+#define KINETIS_PIT2_IRQ 70
+#define KINETIS_PIT3_IRQ 71
+
+/*
+ * PIT Timer Control Register
+ */
+/* Timer Interrupt Enable Bit */
+#define KINETIS_PIT_TCTRL_TIE_MSK (1 << 1)
+/* Timer Enable Bit */
+#define KINETIS_PIT_TCTRL_TEN_MSK (1 << 0)
+/*
+ * PIT Timer Flag Register
+ */
+/* Timer Interrupt Flag */
+#define KINETIS_PIT_TFLG_TIF_MSK (1 << 0)
+
+/*
+ * PIT control registers base
+ */
+#define KINETIS_PIT_BASE (KINETIS_AIPS0PERIPH_BASE + 0x00037000)
+#define KINETIS_PIT_MCR IOMEM(KINETIS_PIT_BASE + 0x0)
+
+/*
+ * Periodic Interrupt Timer (PIT) registers
+ */
+struct kinetis_pit_channel_regs {
+ u32 ldval; /* Timer Load Value Register */
+ u32 cval; /* Current Timer Value Register */
+ u32 tctrl; /* Timer Control Register */
+ u32 tflg; /* Timer Flag Register */
+};
+
+#define KINETIS_PIT_PTR(base, reg) \
+ (&(((struct kinetis_pit_channel_regs *)(base))->reg))
+#define KINETIS_PIT_RD(base, reg) readl(KINETIS_PIT_PTR(base, reg))
+#define KINETIS_PIT_WR(base, reg, val) \
+ writel((val), KINETIS_PIT_PTR(base, reg))
+#define KINETIS_PIT_SET(base, reg, mask) \
+ KINETIS_PIT_WR(base, reg, (KINETIS_PIT_RD(base, reg)) | (mask))
+#define KINETIS_PIT_RESET(base, reg, mask) \
+ KINETIS_PIT_WR(base, reg, (KINETIS_PIT_RD(base, reg)) & (~(mask)))
+
+struct kinetis_clock_event_ddata {
+ struct clock_event_device evtdev;
+ void __iomem *base;
+};
+
+/*
+ * Enable or disable a PIT channel
+ */
+static void kinetis_pit_enable(void __iomem *base, int enable)
+{
+ if (enable)
+ KINETIS_PIT_SET(base, tctrl, KINETIS_PIT_TCTRL_TEN_MSK);
+ else
+ KINETIS_PIT_RESET(base, tctrl, KINETIS_PIT_TCTRL_TEN_MSK);
+}
+
+/*
+ * Initialize a PIT channel, but do not enable it
+ */
+static void kinetis_pit_init(void __iomem *base, u32 ticks)
+{
+ /*
+ * Enable the PIT module clock
+ */
+ writel(0, KINETIS_PIT_MCR);
+
+ KINETIS_PIT_WR(base, tctrl, 0);
+ KINETIS_PIT_WR(base, tflg, KINETIS_PIT_TFLG_TIF_MSK);
+ KINETIS_PIT_WR(base, ldval, ticks);
+ KINETIS_PIT_WR(base, cval, 0);
+ KINETIS_PIT_WR(base, tctrl, KINETIS_PIT_TCTRL_TIE_MSK);
+}
+
+/*
+ * Clock event device set mode function
+ */
+static void kinetis_clockevent_tmr_set_mode(
+ enum clock_event_mode mode, struct clock_event_device *clk)
+{
+ struct kinetis_clock_event_ddata *pit =
+ container_of(clk, struct kinetis_clock_event_ddata, evtdev);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ kinetis_pit_enable(pit->base, 1);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ default:
+ kinetis_pit_enable(pit->base, 0);
+ }
+}
+
+/*
+ * Configure the timer to generate an interrupt in the specified amount of ticks
+ */
+static int kinetis_clockevent_tmr_set_next_event(
+ unsigned long delta, struct clock_event_device *c)
+{
+ struct kinetis_clock_event_ddata *pit =
+ container_of(c, struct kinetis_clock_event_ddata, evtdev);
+ unsigned long flags;
+
+ raw_local_irq_save(flags);
+ kinetis_pit_init(pit->base, delta);
+ kinetis_pit_enable(pit->base, 1);
+ raw_local_irq_restore(flags);
+
+ return 0;
+}
+
+static struct kinetis_clock_event_ddata
+ kinetis_clockevent_tmrs[KINETIS_PIT_CHANNELS] = {
+ {
+ .evtdev = {
+ .name = "fsl,kinetis-pit-timer0",
+ .rating = 200,
+ .features =
+ CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = kinetis_clockevent_tmr_set_mode,
+ .set_next_event = kinetis_clockevent_tmr_set_next_event,
+ },
+ },
+ {
+ .evtdev = {
+ .name = "fsl,kinetis-pit-timer1",
+ },
+ },
+ {
+ .evtdev = {
+ .name = "fsl,kinetis-pit-timer2",
+ },
+ },
+ {
+ .evtdev = {
+ .name = "fsl,kinetis-pit-timer3",
+ },
+ },
+};
+
+/*
+ * Timer IRQ handler
+ */
+static irqreturn_t kinetis_clockevent_tmr_irq_handler(int irq, void *dev_id)
+{
+ struct kinetis_clock_event_ddata *tmr = dev_id;
+
+ KINETIS_PIT_WR(tmr->base, tflg, KINETIS_PIT_TFLG_TIF_MSK);
+
+ tmr->evtdev.event_handler(&(tmr->evtdev));
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * System timer IRQ action
+ */
+static struct irqaction kinetis_clockevent_irqaction[KINETIS_PIT_CHANNELS] = {
+ {
+ .name = "Kinetis Kernel Time Tick (pit0)",
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &kinetis_clockevent_tmrs[0],
+ .handler = kinetis_clockevent_tmr_irq_handler,
+ }, {
+ .name = "Kinetis Kernel Time Tick (pit1)",
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &kinetis_clockevent_tmrs[1],
+ .handler = kinetis_clockevent_tmr_irq_handler,
+ }, {
+ .name = "Kinetis Kernel Time Tick (pit2)",
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &kinetis_clockevent_tmrs[2],
+ .handler = kinetis_clockevent_tmr_irq_handler,
+ }, {
+ .name = "Kinetis Kernel Time Tick (pit3)",
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &kinetis_clockevent_tmrs[3],
+ .handler = kinetis_clockevent_tmr_irq_handler,
+ },
+};
+
+static void __init kinetis_clockevent_init(struct device_node *np)
+{
+ const u64 max_delay_in_sec = 5;
+ struct clk *clk;
+ void __iomem *base;
+ unsigned long rate;
+ int irq, chan;
+
+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ pr_err("failed to get clock for clockevent\n");
+ return;
+ }
+
+ if (clk_prepare_enable(clk)) {
+ pr_err("failed to enable timer clock for clockevent\n");
+ goto err_clk_enable;
+ }
+
+ rate = clk_get_rate(clk);
+ if (!(rate / HZ)) {
+ pr_err("failed to get proper clock rate for clockevent\n");
+ goto err_clk_enable;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("failed to get map registers for clockevent\n");
+ goto err_iomap;
+ }
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0) {
+ pr_err("failed to get irq for clockevent\n");
+ goto err_get_irq;
+ }
+
+ chan = of_alias_get_id(np, "pit");
+ if ((chan < 0) || (chan >= KINETIS_PIT_CHANNELS)) {
+ pr_err("failed to calculate channel number for clockevent\n");
+ goto err_get_irq;
+ }
+ kinetis_clockevent_tmrs[chan].base = base;
+
+ /*
+ * Set the fields required for the set_next_event method
+ * (tickless kernel support)
+ */
+ clockevents_calc_mult_shift(&(kinetis_clockevent_tmrs[chan].evtdev),
+ rate, max_delay_in_sec);
+ kinetis_clockevent_tmrs[chan].evtdev.max_delta_ns =
+ max_delay_in_sec * NSEC_PER_SEC;
+ kinetis_clockevent_tmrs[chan].evtdev.min_delta_ns =
+ clockevent_delta2ns(0xf,
+ &(kinetis_clockevent_tmrs[chan].evtdev));
+
+ clockevents_register_device(&(kinetis_clockevent_tmrs[chan].evtdev));
+
+ kinetis_pit_init(base, (rate / HZ) - 1);
+ kinetis_pit_enable(base, 1);
+
+ setup_irq(irq, &(kinetis_clockevent_irqaction[chan]));
+
+ return;
+
+err_get_irq:
+
+ iounmap(base);
+err_iomap:
+
+ clk_disable_unprepare(clk);
+err_clk_enable:
+
+ clk_put(clk);
+}
+
+CLOCKSOURCE_OF_DECLARE(kinetis_pit_timer, "fsl,kinetis-pit-timer",
+ kinetis_clockevent_init);
diff --git a/include/dt-bindings/clock/kinetis-mcg.h b/include/dt-bindings/clock/kinetis-mcg.h
new file mode 100644
index 0000000..681732f
--- /dev/null
+++ b/include/dt-bindings/clock/kinetis-mcg.h
@@ -0,0 +1,10 @@
+#ifndef _DT_BINDINGS_CLOCK_KINETIS_MCG_H
+#define _DT_BINDINGS_CLOCK_KINETIS_MCG_H
+
+#define CLOCK_MCGOUTCLK 0
+#define CLOCK_CCLK 1
+#define CLOCK_PCLK 2
+#define CLOCK_PIT 3
+#define CLOCK_END 4
+
+#endif /* _DT_BINDINGS_CLOCK_KINETIS_MCG_H */
--
2.3.6

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