[PATCH v2 3/9] arm: twr-k70f120m: clock driver for Kinetis SoC

From: Paul Osmialowski
Date: Tue Jun 30 2015 - 08:33:55 EST


Based on K70P256M150SF3RM.pdf K70 Sub-Family Reference Manual, Rev. 3.

Signed-off-by: Paul Osmialowski <pawelo@xxxxxxxxxxx>
---
.../devicetree/bindings/clock/kinetis-clock.txt | 63 +++
arch/arm/boot/dts/kinetis.dtsi | 36 ++
drivers/clk/Makefile | 1 +
drivers/clk/clk-kinetis.c | 463 +++++++++++++++++++++
4 files changed, 563 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/kinetis-clock.txt
create mode 100644 drivers/clk/clk-kinetis.c

diff --git a/Documentation/devicetree/bindings/clock/kinetis-clock.txt b/Documentation/devicetree/bindings/clock/kinetis-clock.txt
new file mode 100644
index 0000000..63af6a5
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/kinetis-clock.txt
@@ -0,0 +1,63 @@
+* Clock bindings for Freescale Kinetis SoC
+
+Required properties:
+- compatible: Should be "fsl,kinetis-cmu".
+- reg: Two address ranges, one for the Clock Genetator register set,
+ one for System Integration Module register set.
+- Set of clock devices: one fixed-rate-root, fixed-rate clocks and clock-gates.
+
+For clock-gate addresses see K70 Sub-Family Reference Manual, Rev. 3 pg. 341
+and later. Notice that addresses are zero-based, so SIM_SCGC1 has address 0,
+SIM_SCGC2 has address 1 and so on. The second address component is the bit
+index.
+
+Example:
+
+cmu@40064000 {
+ compatible = "fsl,kinetis-cmu";
+ reg = <0x40064000 0x14>, <0x40047000 0x1100>;
+
+ mcg_outclk: fixed-rate-root@mcgout {
+ device_type = "mcgout";
+ #clock-cells = <0>;
+ };
+
+ mcg_cclk: fixed-rate@cclk {
+ device_type = "cclk";
+ #clock-cells = <0>;
+ clocks = <&mcg_outclk>;
+ };
+
+ mcg_pclk: fixed-rate@pclk {
+ device_type = "pclk";
+ #clock-cells = <0>;
+ clocks = <&mcg_outclk>;
+ };
+
+ mcg_cclk_gate: clock-gate@cclk {
+ #clock-cells = <2>;
+ clocks = <&mcg_cclk>;
+ };
+
+ mcg_pclk_gate: clock-gate@pclk {
+ #clock-cells = <2>;
+ clocks = <&mcg_pclk>;
+ };
+};
+
+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_cclk_gate 3 11>;
+ clock-names = "ipg";
+ dmas = <&edma 0 4>;
+ dma-names = "rx";
+};
diff --git a/arch/arm/boot/dts/kinetis.dtsi b/arch/arm/boot/dts/kinetis.dtsi
index 93d2a8a..ae0cf00 100644
--- a/arch/arm/boot/dts/kinetis.dtsi
+++ b/arch/arm/boot/dts/kinetis.dtsi
@@ -3,3 +3,39 @@
*
*/
#include "armv7-m.dtsi"
+
+/ {
+ soc {
+ cmu@40064000 {
+ compatible = "fsl,kinetis-cmu";
+ reg = <0x40064000 0x14>, <0x40047000 0x1100>;
+
+ mcg_outclk: fixed-rate-root@mcgout {
+ device_type = "mcgout";
+ #clock-cells = <0>;
+ };
+
+ mcg_cclk: fixed-rate@cclk {
+ device_type = "cclk";
+ #clock-cells = <0>;
+ clocks = <&mcg_outclk>;
+ };
+
+ mcg_pclk: fixed-rate@pclk {
+ device_type = "pclk";
+ #clock-cells = <0>;
+ clocks = <&mcg_outclk>;
+ };
+
+ mcg_cclk_gate: clock-gate@cclk {
+ #clock-cells = <2>;
+ clocks = <&mcg_cclk>;
+ };
+
+ mcg_pclk_gate: clock-gate@pclk {
+ #clock-cells = <2>;
+ clocks = <&mcg_pclk>;
+ };
+ };
+ };
+};
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 63418cf..412d76b 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..611e2e9
--- /dev/null
+++ b/drivers/clk/clk-kinetis.c
@@ -0,0 +1,463 @@
+/*
+ * clk-kinetis.c - Clock driver for Kinetis K70 MCG
+ *
+ * Based on legacy pre-OF code by Alexander Potashev <aspotashev@xxxxxxxxxxx>
+ *
+ * Copyright (C) 2015 Paul Osmialowski <pawelo@xxxxxxxxxxx>
+ *
+ * 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/io.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.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 */
+
+#define KINETIS_SIM_CG_NUMREGS 7
+
+/*
+ * System Integration Module (SIM) register map
+ *
+ * This map actually covers two hardware modules:
+ * 1. SIM low-power logic, at 0x40047000
+ * 2. System integration module (SIM), at 0x40048000
+ */
+struct kinetis_sim_regs {
+ u32 sopt1; /* System Options Register 1 */
+ u32 rsv0[1024];
+ u32 sopt2; /* System Options Register 2 */
+ u32 rsv1;
+ u32 sopt4; /* System Options Register 4 */
+ u32 sopt5; /* System Options Register 5 */
+ u32 sopt6; /* System Options Register 6 */
+ u32 sopt7; /* System Options Register 7 */
+ u32 rsv2[2];
+ u32 sdid; /* System Device Identification Register */
+ u32 scgc[KINETIS_SIM_CG_NUMREGS]; /* Clock Gating Regs 1...7 */
+ u32 clkdiv1; /* System Clock Divider Register 1 */
+ u32 clkdiv2; /* System Clock Divider Register 2 */
+ u32 fcfg1; /* Flash Configuration Register 1 */
+ u32 fcfg2; /* Flash Configuration Register 2 */
+ u32 uidh; /* Unique Identification Register High */
+ u32 uidmh; /* Unique Identification Register Mid-High */
+ u32 uidml; /* Unique Identification Register Mid Low */
+ u32 uidl; /* Unique Identification Register Low */
+ u32 clkdiv3; /* System Clock Divider Register 3 */
+ u32 clkdiv4; /* System Clock Divider Register 4 */
+ u32 mcr; /* Misc Control Register */
+};
+
+/*
+ * SIM registers base
+ */
+#define KINETIS_SIM_PTR(base, reg) \
+ (&(((struct kinetis_sim_regs *)(base))->reg))
+#define KINETIS_SIM_RD(be, base, reg) \
+ ((be) ? ioread32be(KINETIS_SIM_PTR(base, reg)) \
+ : ioread32(KINETIS_SIM_PTR(base, reg)))
+#define KINETIS_SIM_WR(be, base, reg, val) do { \
+ if (be) \
+ iowrite32be((val), KINETIS_SIM_PTR(base, reg)); \
+ else \
+ iowrite32((val), KINETIS_SIM_PTR(base, reg)); \
+ } while (0)
+#define KINETIS_SIM_SET(be, base, reg, mask) \
+ KINETIS_SIM_WR(be, base, reg, \
+ KINETIS_SIM_RD(be, base, reg) | (mask))
+#define KINETIS_SIM_RESET(be, base, reg, mask) \
+ KINETIS_SIM_WR(be, base, reg, \
+ KINETIS_SIM_RD(be, base, reg) & (~(mask)))
+
+/*
+ * System Clock Divider Register 1
+ */
+/* Clock 1 output divider value (for the core/system clock) */
+#define KINETIS_SIM_CLKDIV1_OUTDIV1_BITS 28
+#define KINETIS_SIM_CLKDIV1_OUTDIV1_MSK \
+ (((1 << 4) - 1) << KINETIS_SIM_CLKDIV1_OUTDIV1_BITS)
+/* Clock 2 output divider value (for the peripheral clock) */
+#define KINETIS_SIM_CLKDIV1_OUTDIV2_BITS 24
+#define KINETIS_SIM_CLKDIV1_OUTDIV2_MSK \
+ (((1 << 4) - 1) << KINETIS_SIM_CLKDIV1_OUTDIV2_BITS)
+
+/*
+ * System Clock Divider Register 2
+ */
+/* USB HS clock divider fraction */
+#define KINETIS_SIM_CLKDIV2_USBHSFRAC_BIT 8
+#define KINETIS_SIM_CLKDIV2_USBHSFRAC_MSK \
+ (1 << KINETIS_SIM_CLKDIV2_USBHSFRAC_BIT)
+/* USB HS clock divider divisor */
+#define KINETIS_SIM_CLKDIV2_USBHSDIV_BIT 9
+#define KINETIS_SIM_CLKDIV2_USBHSDIV_MSK \
+ (7 << KINETIS_SIM_CLKDIV2_USBHSDIV_BIT)
+
+/*
+ * 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))
+
+struct kinetis_clk_gate {
+ const char *clk_gate_name;
+ struct clk *clk;
+ u32 reg;
+ u32 idx;
+ struct list_head clk_list;
+};
+
+struct kinetis_clk_gate_data {
+ const char *clk_parent_name;
+ void __iomem *sim;
+ struct list_head clk_gate_list;
+};
+
+static struct clk *kinetis_find_clk_gate(
+ struct kinetis_clk_gate_data *clk_gate_data, u32 reg, u32 idx)
+{
+ struct kinetis_clk_gate *gate;
+
+ list_for_each_entry(gate, &clk_gate_data->clk_gate_list, clk_list)
+ if ((gate->reg == reg) && (gate->idx == idx))
+ return gate->clk;
+
+ return NULL;
+}
+
+static struct clk *kinetis_clk_gate_get(struct of_phandle_args *clkspec,
+ void *data)
+{
+ struct kinetis_clk_gate_data *clk_gate_data = data;
+ struct kinetis_clk_gate *gate;
+ u32 reg = clkspec->args[0];
+ u32 idx = clkspec->args[1];
+ struct clk *clk;
+
+ clk = kinetis_find_clk_gate(clk_gate_data, reg, idx);
+ if (clk)
+ return clk;
+
+ gate = kzalloc(sizeof(struct kinetis_clk_gate), GFP_KERNEL);
+ if (!gate)
+ return ERR_PTR(-ENOMEM);
+ gate->clk_gate_name = kasprintf(GFP_KERNEL, "%s:%u:%u",
+ clkspec->np->full_name, reg, idx);
+
+ clk = clk_register_gate(NULL, gate->clk_gate_name,
+ clk_gate_data->clk_parent_name, 0,
+ KINETIS_SIM_PTR(clk_gate_data->sim, scgc[reg]),
+ idx, 0, NULL);
+ if (IS_ERR(clk)) {
+ pr_err("Cannot register gate to clock %s\n",
+ clk_gate_data->clk_parent_name);
+ kfree_const(gate->clk_gate_name);
+ kfree(gate);
+ return clk;
+ }
+
+ gate->clk = clk;
+ gate->reg = reg;
+ gate->idx = idx;
+
+ list_add(&gate->clk_list, &clk_gate_data->clk_gate_list);
+
+ return clk;
+}
+
+static const char *kinetis_of_clk_get_name(struct device_node *np)
+{
+ struct of_phandle_args clkspec;
+ int ret;
+ const char *retval;
+
+ ret = of_parse_phandle_with_args(np, "clocks", "#clock-cells", 0,
+ &clkspec);
+ if (ret)
+ return ERR_PTR(ret);
+
+ retval = clkspec.np->full_name;
+
+ of_node_put(clkspec.np);
+
+ return retval;
+}
+
+static void __init kinetis_mcg_init(struct device_node *np)
+{
+ const int vco_div = 2;
+ const int vdiv_min = 16;
+ u32 clock_val_mcgout;
+ u32 clock_val_cclk;
+ u32 clock_val_pclk;
+ u32 clock_val;
+ void __iomem *base;
+ void __iomem *sim;
+ int pll_sel;
+ int osc_sel;
+ unsigned long mcgout;
+ struct clk *clk;
+ const char *clk_parent_name;
+ struct kinetis_clk_gate_data *clk_gate;
+ struct device_node *child;
+ bool big_endian;
+ int ret;
+
+ big_endian = of_property_read_bool(np, "big-endian");
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("Failed to map address range for kinetis,mcg node\n");
+ return;
+ }
+
+ sim = of_iomap(np, 1);
+ if (!sim) {
+ pr_err("Failed to map address range for kinetis SIM module\n");
+ iounmap(base);
+ 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_mcgout = mcgout;
+
+ clock_val_cclk = mcgout /
+ (((KINETIS_SIM_RD(big_endian, sim, clkdiv1) &
+ KINETIS_SIM_CLKDIV1_OUTDIV1_MSK) >>
+ KINETIS_SIM_CLKDIV1_OUTDIV1_BITS) + 1);
+
+ /*
+ * Peripheral (bus) clock
+ */
+ clock_val_pclk = mcgout /
+ (((KINETIS_SIM_RD(big_endian, sim, clkdiv1) &
+ KINETIS_SIM_CLKDIV1_OUTDIV2_MSK) >>
+ KINETIS_SIM_CLKDIV1_OUTDIV2_BITS) + 1);
+
+ for_each_child_of_node(np, child) {
+ if (!of_device_is_available(child))
+ continue;
+
+ clock_val = 0;
+ if (child->type) {
+ if (!of_node_cmp(child->type, "mcgout"))
+ clock_val = clock_val_mcgout;
+ else if (!of_node_cmp(child->type, "cclk"))
+ clock_val = clock_val_cclk;
+ else if (!of_node_cmp(child->type, "pclk"))
+ clock_val = clock_val_pclk;
+ }
+
+ if (!of_node_cmp(child->name, "fixed-rate-root")) {
+ clk = clk_register_fixed_rate(NULL, child->full_name,
+ NULL, CLK_IS_ROOT, clock_val);
+ if (IS_ERR(clk)) {
+ pr_err("Could not register clock %s\n",
+ child->full_name);
+ continue;
+ }
+
+ ret = of_clk_add_provider(child, of_clk_src_simple_get,
+ clk);
+ if (ret < 0) {
+ pr_err("Could not add clock provider %s\n",
+ child->full_name);
+ continue;
+ }
+ } else if (!of_node_cmp(child->name, "fixed-rate")) {
+ clk_parent_name = kinetis_of_clk_get_name(child);
+ if (IS_ERR(clk_parent_name)) {
+ pr_err("Could not get parent clk name for %s\n",
+ child->full_name);
+ }
+
+ clk = clk_register_fixed_rate(NULL, child->full_name,
+ clk_parent_name, 0, clock_val);
+ if (IS_ERR(clk)) {
+ pr_err("Could not register clock %s\n",
+ child->full_name);
+ continue;
+ }
+
+ ret = of_clk_add_provider(child, of_clk_src_simple_get,
+ clk);
+ if (ret < 0) {
+ pr_err("Could not add clock provider %s\n",
+ child->full_name);
+ continue;
+ }
+ } else if (!of_node_cmp(child->name, "clock-gate")) {
+ clk_parent_name = kinetis_of_clk_get_name(child);
+ if (IS_ERR(clk_parent_name)) {
+ pr_err("Could not get parent clk name for %s\n",
+ child->full_name);
+ }
+
+ clk_gate = kzalloc(sizeof(struct kinetis_clk_gate_data),
+ GFP_KERNEL);
+ if (!clk_gate)
+ continue;
+
+ clk_gate->clk_parent_name = clk_parent_name;
+ clk_gate->sim = sim;
+ INIT_LIST_HEAD(&clk_gate->clk_gate_list);
+
+ ret = of_clk_add_provider(child, kinetis_clk_gate_get,
+ clk_gate);
+ if (ret < 0) {
+ pr_err("Could not add clock provider %s\n",
+ child->full_name);
+ continue;
+ }
+ } else {
+ pr_err("Unknown clock name\n");
+ continue;
+ }
+ }
+}
+
+CLK_OF_DECLARE(kinetis_mcg, "fsl,kinetis-cmu", kinetis_mcg_init);
--
2.3.6

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