clk: Add Actions Semi OWL clock support

This commit adds Actions Semi OWL family base clock and S900 SoC
specific clock support. For S900 peripheral clock support, only UART
clock has been added for now.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/arm/include/asm/arch-owl/clk_s900.h

@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Actions Semi S900 Clock Definitions
+ *
+ * Copyright (C) 2015 Actions Semi Co., Ltd.
+ * Copyright (C) 2018 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+ *
+ */
+
+#ifndef _OWL_CLK_S900_H_
+#define _OWL_CLK_S900_H_
+
+#include <clk-uclass.h>
+
+struct owl_clk_priv {
+	phys_addr_t base;
+};
+
+/* BUSCLK register definitions */
+#define CMU_PDBGDIV_8		7
+#define CMU_PDBGDIV_SHIFT	26
+#define CMU_PDBGDIV_DIV		(CMU_PDBGDIV_8 << CMU_PDBGDIV_SHIFT)
+#define CMU_PERDIV_8		7
+#define CMU_PERDIV_SHIFT	20
+#define CMU_PERDIV_DIV		(CMU_PERDIV_8 << CMU_PERDIV_SHIFT)
+#define CMU_NOCDIV_2		1
+#define CMU_NOCDIV_SHIFT	19
+#define CMU_NOCDIV_DIV		(CMU_NOCDIV_2 << CMU_NOCDIV_SHIFT)
+#define CMU_DMMCLK_SRC_APLL	2
+#define CMU_DMMCLK_SRC_SHIFT	10
+#define CMU_DMMCLK_SRC		(CMU_DMMCLK_SRC_APLL << CMU_DMMCLK_SRC_SHIFT)
+#define CMU_APBCLK_DIV		BIT(8)
+#define CMU_NOCCLK_SRC		BIT(7)
+#define CMU_AHBCLK_DIV		BIT(4)
+#define CMU_CORECLK_MASK	3
+#define CMU_CORECLK_CPLL	BIT(1)
+#define CMU_CORECLK_HOSC	BIT(0)
+
+/* COREPLL register definitions */
+#define CMU_COREPLL_EN		BIT(9)
+#define CMU_COREPLL_HOSC_EN	BIT(8)
+#define CMU_COREPLL_OUT		(1104 / 24)
+
+/* DEVPLL register definitions */
+#define CMU_DEVPLL_CLK		BIT(12)
+#define CMU_DEVPLL_EN		BIT(8)
+#define CMU_DEVPLL_OUT		(660 / 6)
+
+/* UARTCLK register definitions */
+#define CMU_UARTCLK_SRC_DEVPLL	BIT(16)
+
+/* DEVCLKEN1 register definitions */
+#define CMU_DEVCLKEN1_UART5	BIT(21)
+
+#define PLL_STABILITY_WAIT_US	50
+
+#endif

arch/arm/include/asm/arch-owl/regs_s900.h

@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Actions Semi S900 Register Definitions
+ *
+ * Copyright (C) 2015 Actions Semi Co., Ltd.
+ * Copyright (C) 2018 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+ *
+ */
+
+#ifndef _OWL_REGS_S900_H_
+#define _OWL_REGS_S900_H_
+
+/* CMU registers */
+#define CMU_COREPLL				(0x0000)
+#define CMU_DEVPLL				(0x0004)
+#define CMU_DDRPLL				(0x0008)
+#define CMU_NANDPLL				(0x000C)
+#define CMU_DISPLAYPLL				(0x0010)
+#define CMU_AUDIOPLL				(0x0014)
+#define CMU_TVOUTPLL				(0x0018)
+#define CMU_BUSCLK				(0x001C)
+#define CMU_SENSORCLK				(0x0020)
+#define CMU_LCDCLK				(0x0024)
+#define CMU_DSICLK				(0x0028)
+#define CMU_CSICLK				(0x002C)
+#define CMU_DECLK				(0x0030)
+#define CMU_BISPCLK				(0x0034)
+#define CMU_IMXCLK				(0x0038)
+#define CMU_HDECLK				(0x003C)
+#define CMU_VDECLK				(0x0040)
+#define CMU_VCECLK				(0x0044)
+#define CMU_NANDCCLK				(0x004C)
+#define CMU_SD0CLK				(0x0050)
+#define CMU_SD1CLK				(0x0054)
+#define CMU_SD2CLK				(0x0058)
+#define CMU_UART0CLK				(0x005C)
+#define CMU_UART1CLK				(0x0060)
+#define CMU_UART2CLK				(0x0064)
+#define CMU_PWM0CLK				(0x0070)
+#define CMU_PWM1CLK				(0x0074)
+#define CMU_PWM2CLK				(0x0078)
+#define CMU_PWM3CLK				(0x007C)
+#define CMU_USBPLL				(0x0080)
+#define CMU_ASSISTPLL				(0x0084)
+#define CMU_EDPCLK				(0x0088)
+#define CMU_GPU3DCLK				(0x0090)
+#define CMU_CORECTL				(0x009C)
+#define CMU_DEVCLKEN0				(0x00A0)
+#define CMU_DEVCLKEN1				(0x00A4)
+#define CMU_DEVRST0				(0x00A8)
+#define CMU_DEVRST1				(0x00AC)
+#define CMU_UART3CLK				(0x00B0)
+#define CMU_UART4CLK				(0x00B4)
+#define CMU_UART5CLK				(0x00B8)
+#define CMU_UART6CLK				(0x00BC)
+#define CMU_TLSCLK				(0x00C0)
+#define CMU_SD3CLK				(0x00C4)
+#define CMU_PWM4CLK				(0x00C8)
+#define CMU_PWM5CLK				(0x00CC)
+#define CMU_ANALOGDEBUG				(0x00D4)
+#define CMU_TVOUTPLLDEBUG0			(0x00EC)
+#define CMU_TVOUTPLLDEBUG1			(0x00FC)
+
+#endif

drivers/clk/Kconfig

@@ -89,6 +89,7 @@ source "drivers/clk/exynos/Kconfig"
 source "drivers/clk/at91/Kconfig"
 source "drivers/clk/renesas/Kconfig"
 source "drivers/clk/mvebu/Kconfig"
+source "drivers/clk/owl/Kconfig"
 
 config ICS8N3QV01
 	bool "Enable ICS8N3QV01 VCXO driver"

drivers/clk/Makefile

@@ -17,6 +17,7 @@ obj-$(CONFIG_CLK_BCM6345) += clk_bcm6345.o
 obj-$(CONFIG_CLK_BOSTON) += clk_boston.o
 obj-$(CONFIG_CLK_EXYNOS) += exynos/
 obj-$(CONFIG_CLK_HSDK) += clk-hsdk-cgu.o
+obj-$(CONFIG_CLK_OWL) += owl/
 obj-$(CONFIG_CLK_RENESAS) += renesas/
 obj-$(CONFIG_CLK_STM32F) += clk_stm32f.o
 obj-$(CONFIG_CLK_STM32MP1) += clk_stm32mp1.o

drivers/clk/owl/Kconfig

@@ -0,0 +1,12 @@
+config CLK_OWL
+        bool "Actions Semi OWL clock drivers"
+        depends on CLK && ARCH_OWL
+        help
+          Enable support for clock managemet unit present in Actions Semi
+	  OWL SoCs.
+
+config CLK_S900
+        bool "Actions Semi S900 clock driver"
+        depends on CLK_OWL && ARM64
+        help
+          Enable support for the clocks in Actions Semi S900 SoC.

drivers/clk/owl/Makefile

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier:	GPL-2.0+
+
+obj-$(CONFIG_CLK_S900) += clk_s900.o

drivers/clk/owl/clk_s900.c

@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Actions Semi S900 clock driver
+ *
+ * Copyright (C) 2015 Actions Semi Co., Ltd.
+ * Copyright (C) 2018 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/arch-owl/clk_s900.h>
+#include <asm/arch-owl/regs_s900.h>
+#include <asm/io.h>
+
+#include <dt-bindings/clock/s900_cmu.h>
+
+void owl_clk_init(struct owl_clk_priv *priv)
+{
+	u32 bus_clk = 0, core_pll, dev_pll;
+
+	/* Enable ASSIST_PLL */
+	setbits_le32(priv->base + CMU_ASSISTPLL, BIT(0));
+
+	udelay(PLL_STABILITY_WAIT_US);
+
+	/* Source HOSC to DEV_CLK */
+	clrbits_le32(priv->base + CMU_DEVPLL, CMU_DEVPLL_CLK);
+
+	/* Configure BUS_CLK */
+	bus_clk |= (CMU_PDBGDIV_DIV | CMU_PERDIV_DIV | CMU_NOCDIV_DIV |
+			CMU_DMMCLK_SRC | CMU_APBCLK_DIV | CMU_AHBCLK_DIV |
+			CMU_NOCCLK_SRC | CMU_CORECLK_HOSC);
+	writel(bus_clk, priv->base + CMU_BUSCLK);
+
+	udelay(PLL_STABILITY_WAIT_US);
+
+	/* Configure CORE_PLL */
+	core_pll = readl(priv->base + CMU_COREPLL);
+	core_pll |= (CMU_COREPLL_EN | CMU_COREPLL_HOSC_EN | CMU_COREPLL_OUT);
+	writel(core_pll, priv->base + CMU_COREPLL);
+
+	udelay(PLL_STABILITY_WAIT_US);
+
+	/* Configure DEV_PLL */
+	dev_pll = readl(priv->base + CMU_DEVPLL);
+	dev_pll |= (CMU_DEVPLL_EN | CMU_DEVPLL_OUT);
+	writel(dev_pll, priv->base + CMU_DEVPLL);
+
+	udelay(PLL_STABILITY_WAIT_US);
+
+	/* Source CORE_PLL for CORE_CLK */
+	clrsetbits_le32(priv->base + CMU_BUSCLK, CMU_CORECLK_MASK,
+			CMU_CORECLK_CPLL);
+
+	/* Source DEV_PLL for DEV_CLK */
+	setbits_le32(priv->base + CMU_DEVPLL, CMU_DEVPLL_CLK);
+
+	udelay(PLL_STABILITY_WAIT_US);
+}
+
+void owl_uart_clk_enable(struct owl_clk_priv *priv)
+{
+	/* Source HOSC for UART5 interface */
+	clrbits_le32(priv->base + CMU_UART5CLK, CMU_UARTCLK_SRC_DEVPLL);
+
+	/* Enable UART5 interface clock */
+	setbits_le32(priv->base + CMU_DEVCLKEN1, CMU_DEVCLKEN1_UART5);
+}
+
+void owl_uart_clk_disable(struct owl_clk_priv *priv)
+{
+	/* Disable UART5 interface clock */
+	clrbits_le32(priv->base + CMU_DEVCLKEN1, CMU_DEVCLKEN1_UART5);
+}
+
+int owl_clk_enable(struct clk *clk)
+{
+	struct owl_clk_priv *priv = dev_get_priv(clk->dev);
+
+	switch (clk->id) {
+	case CLOCK_UART5:
+		owl_uart_clk_enable(priv);
+		break;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+int owl_clk_disable(struct clk *clk)
+{
+	struct owl_clk_priv *priv = dev_get_priv(clk->dev);
+
+	switch (clk->id) {
+	case CLOCK_UART5:
+		owl_uart_clk_disable(priv);
+		break;
+	default:
+		return 0;
+	}
+
+	return 0;
+}
+
+static int owl_clk_probe(struct udevice *dev)
+{
+	struct owl_clk_priv *priv = dev_get_priv(dev);
+
+	priv->base = dev_read_addr(dev);
+	if (priv->base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	/* setup necessary clocks */
+	owl_clk_init(priv);
+
+	return 0;
+}
+
+static struct clk_ops owl_clk_ops = {
+	.enable = owl_clk_enable,
+	.disable = owl_clk_disable,
+};
+
+static const struct udevice_id owl_clk_ids[] = {
+	{ .compatible = "actions,s900-cmu" },
+	{ }
+};
+
+U_BOOT_DRIVER(clk_owl) = {
+	.name		= "clk_s900",
+	.id		= UCLASS_CLK,
+	.of_match	= owl_clk_ids,
+	.ops		= &owl_clk_ops,
+	.priv_auto_alloc_size = sizeof(struct owl_clk_priv),
+	.probe		= owl_clk_probe,
+	.flags		= DM_FLAG_PRE_RELOC,
+};