clk: davinci: New driver for davinci PLL clocks

This adds a new driver for mach-davinci PLL clocks. This is porting the
code from arch/arm/mach-davinci/clock.c to the common clock framework.
Additionally, it adds device tree support for these clocks.

The ifeq ($(CONFIG_COMMON_CLK), y) in the Makefile is needed to prevent
compile errors until the clock code in arch/arm/mach-davinci is removed.

Note: although there are similar clocks for TI Keystone we are not able
to share the code for a few reasons. The keystone clocks are device tree
only and use legacy one-node-per-clock bindings. Also the register
layouts are a bit different, which would add even more if/else mess
to the keystone clocks. And the keystone PLL driver doesn't support
setting clock rates.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

MAINTAINERS

@@ -13792,6 +13792,13 @@ F:	arch/arm/mach-davinci/
 F:	drivers/i2c/busses/i2c-davinci.c
 F:	arch/arm/boot/dts/da850*
 
+TI DAVINCI SERIES CLOCK DRIVER
+M:	David Lechner <david@lechnology.com>
+R:	Sekhar Nori <nsekhar@ti.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/clock/ti/davinci/
+F:	drivers/clk/davinci/
+
 TI DAVINCI SERIES GPIO DRIVER
 M:	Keerthy <j-keerthy@ti.com>
 L:	linux-gpio@vger.kernel.org

drivers/clk/Makefile

@@ -61,6 +61,7 @@ obj-$(CONFIG_ARCH_ARTPEC)		+= axis/
 obj-$(CONFIG_ARC_PLAT_AXS10X)		+= axs10x/
 obj-y					+= bcm/
 obj-$(CONFIG_ARCH_BERLIN)		+= berlin/
+obj-$(CONFIG_ARCH_DAVINCI)		+= davinci/
 obj-$(CONFIG_H8300)			+= h8300/
 obj-$(CONFIG_ARCH_HISI)			+= hisilicon/
 obj-y					+= imgtec/

drivers/clk/davinci/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ifeq ($(CONFIG_COMMON_CLK), y)
+obj-y += pll.o
+endif

drivers/clk/davinci/pll.h

@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Clock driver for TI Davinci PSC controllers
+ *
+ * Copyright (C) 2018 David Lechner <david@lechnology.com>
+ */
+
+#ifndef __CLK_DAVINCI_PLL_H___
+#define __CLK_DAVINCI_PLL_H___
+
+#include <linux/bitops.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/types.h>
+
+#define PLL_HAS_CLKMODE			BIT(0) /* PLL has PLLCTL[CLKMODE] */
+#define PLL_HAS_PREDIV			BIT(1) /* has prediv before PLL */
+#define PLL_PREDIV_ALWAYS_ENABLED	BIT(2) /* don't clear DEN bit */
+#define PLL_PREDIV_FIXED_DIV		BIT(3) /* fixed divider value */
+#define PLL_HAS_POSTDIV			BIT(4) /* has postdiv after PLL */
+#define PLL_POSTDIV_ALWAYS_ENABLED	BIT(5) /* don't clear DEN bit */
+#define PLL_POSTDIV_FIXED_DIV		BIT(6) /* fixed divider value */
+#define PLL_HAS_EXTCLKSRC		BIT(7) /* has selectable bypass */
+#define PLL_PLLM_2X			BIT(8) /* PLLM value is 2x (DM365) */
+#define PLL_PREDIV_FIXED8		BIT(9) /* DM355 quirk */
+
+/** davinci_pll_clk_info - controller-specific PLL info
+ * @name: The name of the PLL
+ * @unlock_reg: Option CFGCHIP register for unlocking PLL
+ * @unlock_mask: Bitmask used with @unlock_reg
+ * @pllm_mask: Bitmask for PLLM[PLLM] value
+ * @pllm_min: Minimum allowable value for PLLM[PLLM]
+ * @pllm_max: Maximum allowable value for PLLM[PLLM]
+ * @pllout_min_rate: Minimum allowable rate for PLLOUT
+ * @pllout_max_rate: Maximum allowable rate for PLLOUT
+ * @flags: Bitmap of PLL_* flags.
+ */
+struct davinci_pll_clk_info {
+	const char *name;
+	u32 unlock_reg;
+	u32 unlock_mask;
+	u32 pllm_mask;
+	u32 pllm_min;
+	u32 pllm_max;
+	unsigned long pllout_min_rate;
+	unsigned long pllout_max_rate;
+	u32 flags;
+};
+
+#define SYSCLK_ARM_RATE		BIT(0) /* Controls ARM rate */
+#define SYSCLK_ALWAYS_ENABLED	BIT(1) /* Or bad things happen */
+#define SYSCLK_FIXED_DIV	BIT(2) /* Fixed divider */
+
+/** davinci_pll_sysclk_info - SYSCLKn-specific info
+ * @name: The name of the clock
+ * @parent_name: The name of the parent clock
+ * @id: "n" in "SYSCLKn"
+ * @ratio_width: Width (in bits) of RATIO in PLLDIVn register
+ * @flags: Bitmap of SYSCLK_* flags.
+ */
+struct davinci_pll_sysclk_info {
+	const char *name;
+	const char *parent_name;
+	u32 id;
+	u32 ratio_width;
+	u32 flags;
+};
+
+#define SYSCLK(i, n, p, w, f)				\
+static const struct davinci_pll_sysclk_info n = {	\
+	.name		= #n,				\
+	.parent_name	= #p,				\
+	.id		= (i),				\
+	.ratio_width	= (w),				\
+	.flags		= (f),				\
+}
+
+/** davinci_pll_obsclk_info - OBSCLK-specific info
+ * @name: The name of the clock
+ * @parent_names: Array of names of the parent clocks
+ * @num_parents: Length of @parent_names
+ * @table: Array of values to write to OCSEL[OCSRC] cooresponding to
+ *         @parent_names
+ * @ocsrc_mask: Bitmask for OCSEL[OCSRC]
+ */
+struct davinci_pll_obsclk_info {
+	const char *name;
+	const char * const *parent_names;
+	u8 num_parents;
+	u32 *table;
+	u32 ocsrc_mask;
+};
+
+struct clk *davinci_pll_clk_register(struct device *dev,
+				     const struct davinci_pll_clk_info *info,
+				     const char *parent_name,
+				     void __iomem *base);
+struct clk *davinci_pll_auxclk_register(struct device *dev,
+					const char *name,
+					void __iomem *base);
+struct clk *davinci_pll_sysclkbp_clk_register(struct device *dev,
+					      const char *name,
+					      void __iomem *base);
+struct clk *
+davinci_pll_obsclk_register(struct device *dev,
+			    const struct davinci_pll_obsclk_info *info,
+			    void __iomem *base);
+struct clk *
+davinci_pll_sysclk_register(struct device *dev,
+			    const struct davinci_pll_sysclk_info *info,
+			    void __iomem *base);
+
+int of_davinci_pll_init(struct device *dev,
+			const struct davinci_pll_clk_info *info,
+			const struct davinci_pll_obsclk_info *obsclk_info,
+			const struct davinci_pll_sysclk_info **div_info,
+			u8 max_sysclk_id,
+			void __iomem *base);
+
+#endif /* __CLK_DAVINCI_PLL_H___ */

include/linux/platform_data/clk-davinci-pll.h

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PLL clock driver for TI Davinci SoCs
+ *
+ * Copyright (C) 2018 David Lechner <david@lechnology.com>
+ */
+
+#ifndef __LINUX_PLATFORM_DATA_CLK_DAVINCI_PLL_H__
+#define __LINUX_PLATFORM_DATA_CLK_DAVINCI_PLL_H__
+
+#include <linux/regmap.h>
+
+/**
+ * davinci_pll_platform_data
+ * @cfgchip: CFGCHIP syscon regmap
+ */
+struct davinci_pll_platform_data {
+	struct regmap *cfgchip;
+};
+
+#endif /* __LINUX_PLATFORM_DATA_CLK_DAVINCI_PLL_H__ */