clock_control: Introduce mcux ccm driver

Adds a new clock control driver for i.MX SoCs that have the clock
control module (CCM).

Signed-off-by: Maureen Helm <maureen.helm@nxp.com>

drivers/clock_control/CMakeLists.txt

@@ -1,4 +1,5 @@
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_BEETLE              beetle_clock_control.c)
+zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_CCM            clock_control_mcux_ccm.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_MCUX_SIM            clock_control_mcux_sim.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_NRF5                nrf5_power_clock.c)
 zephyr_sources_ifdef(CONFIG_CLOCK_CONTROL_QUARK_SE            quark_se_clock_control.c)

drivers/clock_control/Kconfig

@@ -49,6 +49,8 @@ source "drivers/clock_control/Kconfig.stm32"
 
 source "drivers/clock_control/Kconfig.beetle"
 
+source "drivers/clock_control/Kconfig.mcux_ccm"
+
 source "drivers/clock_control/Kconfig.mcux_sim"
 
 endif # CLOCK_CONTROL

drivers/clock_control/Kconfig.mcux_ccm

@@ -0,0 +1,14 @@
+# Kconfig - MCUXpresso SDK CCM
+#
+# Copyright (c) 2017, NXP
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+menuconfig CLOCK_CONTROL_MCUX_CCM
+	bool
+	prompt "MCUX CCM driver"
+	depends on HAS_MCUX_CCM
+	default n
+	help
+	  Enable support for mcux ccm driver.

drivers/clock_control/clock_control_mcux_ccm.c

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2017, NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <errno.h>
+#include <soc.h>
+#include <clock_control.h>
+#include <dt-bindings/clock/imx_ccm.h>
+#include <fsl_clock.h>
+
+#define SYS_LOG_LEVEL CONFIG_SYS_LOG_CLOCK_CONTROL_LEVEL
+#include <logging/sys_log.h>
+
+static int mcux_ccm_on(struct device *dev,
+			      clock_control_subsys_t sub_system)
+{
+	return 0;
+}
+
+static int mcux_ccm_off(struct device *dev,
+			       clock_control_subsys_t sub_system)
+{
+	return 0;
+}
+
+static int mcux_ccm_get_subsys_rate(struct device *dev,
+				    clock_control_subsys_t sub_system,
+				    u32_t *rate)
+{
+	u32_t clock_name = (u32_t) sub_system;
+
+	switch (clock_name) {
+	case IMX_CCM_LPUART_CLK:
+		if (CLOCK_GetMux(kCLOCK_UartMux) == 0) {
+			*rate = CLOCK_GetPllFreq(kCLOCK_PllUsb1) / 6
+				/ (CLOCK_GetDiv(kCLOCK_UartDiv) + 1);
+		} else {
+			*rate = CLOCK_GetOscFreq()
+				/ (CLOCK_GetDiv(kCLOCK_UartDiv) + 1);
+		}
+
+		break;
+	}
+
+	return 0;
+}
+
+static int mcux_ccm_init(struct device *dev)
+{
+	return 0;
+}
+
+static const struct clock_control_driver_api mcux_ccm_driver_api = {
+	.on = mcux_ccm_on,
+	.off = mcux_ccm_off,
+	.get_rate = mcux_ccm_get_subsys_rate,
+};
+
+DEVICE_AND_API_INIT(mcux_ccm, CONFIG_MCUX_CCM_NAME,
+		    &mcux_ccm_init,
+		    NULL, NULL,
+		    PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
+		    &mcux_ccm_driver_api);

dts/bindings/clock/nxp,imx-ccm.yaml

@@ -0,0 +1,39 @@
+#
+# Copyright (c) 2017, NXP
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+---
+title: i.MX Clock Controller Module (CCM)
+id: nxp,imx-ccm
+version: 0.1
+
+description: >
+    This is a representation of the i.MX CCM IP node
+
+properties:
+  - compatible:
+      type: string
+      category: required
+      description: compatible strings
+      constraint: "nxp,imx-ccm"
+
+  - reg:
+      type: int
+      description: mmio register space
+      generation: define
+      category: required
+
+  - label:
+      type: string
+      category: required
+      description: Human readable string describing the device (used by Zephyr for API name)
+      generation: define
+
+cell_string: CCM_CLK
+
+"#cells":
+  - name
+  - offset
+  - bits
+...

ext/hal/nxp/mcux/Kconfig

@@ -18,6 +18,12 @@ config HAS_MCUX_ADC16
 	help
 	  Set if the 16-bit ADC (ADC16) module is present in the SoC.
 
+config HAS_MCUX_CCM
+	bool
+	default n
+	help
+	  Set if the clock control module (CCM) module is present in the SoC.
+
 config HAS_MCUX_FTM
 	bool
 	default n

include/dt-bindings/clock/imx_ccm.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2017, NXP
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __IMX_CCM_H
+#define __IMX_CCM_H
+
+#define IMX_CCM_CORESYS_CLK		0
+#define IMX_CCM_PLATFORM_CLK		1
+#define IMX_CCM_BUS_CLK			2
+#define IMX_CCM_LPUART_CLK		3
+#define IMX_CCM_LPI2C_CLK		4
+
+#endif /* __IMX_CCM_H */