AT91 clk driver changes for 5.17:

- Lan966x Generic Clock Controller driver and associated DT bindings
 - Lan966x clock driver extended to support clock gating
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQ5TRCVIBiyi/S+BG4fOrpwrNPNDAUCYbCxYwAKCRAfOrpwrNPN
 DFRwAP9nV1gAI7KGsIGDMBjJpphj9TuZ8u3+PIvxi7pBHPM+lwD/RSJPGTYj4Hpi
 S/MCdFjE4STmKo83Ii3k3/nrPPEuAwQ=
 =BQQ9
 -----END PGP SIGNATURE-----

Merge tag 'clk-at91-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/at91/linux into clk-at91

Pull AT91 clk driver updates from Nicolas Ferre:

 - Lan966x Generic Clock Controller driver and associated DT bindings
 - Lan966x clock driver extended to support clock gating

* tag 'clk-at91-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/at91/linux:
  clk: lan966x: Extend lan966x clock driver for clock gating support
  dt-bindings: clock: lan966x: Extend includes with clock gates
  dt-bindings: clock: lan966x: Extend for clock gate support
  clk: gate: Add devm_clk_hw_register_gate()
  clk: lan966x: Add lan966x SoC clock driver
  dt-bindings: clock: lan966x: Add LAN966X Clock Controller
  dt-bindings: clock: lan966x: Add binding includes for lan966x SoC clock IDs

Documentation/devicetree/bindings/clock/microchip,lan966x-gck.yaml

@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/microchip,lan966x-gck.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip LAN966X Generic Clock Controller
+
+maintainers:
+  - Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
+
+description: |
+  The LAN966X Generic clock controller contains 3 PLLs - cpu_clk,
+  ddr_clk and sys_clk. This clock controller generates and supplies
+  clock to various peripherals within the SoC.
+
+properties:
+  compatible:
+    const: microchip,lan966x-gck
+
+  reg:
+    minItems: 1
+    items:
+      - description: Generic clock registers
+      - description: Optional gate clock registers
+
+  clocks:
+    items:
+      - description: CPU clock source
+      - description: DDR clock source
+      - description: System clock source
+
+  clock-names:
+    items:
+      - const: cpu
+      - const: ddr
+      - const: sys
+
+  '#clock-cells':
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - '#clock-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    clks: clock-controller@e00c00a8 {
+        compatible = "microchip,lan966x-gck";
+        #clock-cells = <1>;
+        clocks = <&cpu_clk>, <&ddr_clk>, <&sys_clk>;
+        clock-names = "cpu", "ddr", "sys";
+        reg = <0xe00c00a8 0x38>;
+    };
+...

drivers/clk/Kconfig

@@ -221,6 +221,13 @@ config COMMON_CLK_GEMINI
 	  This driver supports the SoC clocks on the Cortina Systems Gemini
 	  platform, also known as SL3516 or CS3516.
 
+config COMMON_CLK_LAN966X
+	bool "Generic Clock Controller driver for LAN966X SoC"
+	help
+	  This driver provides support for Generic Clock Controller(GCK) on
+	  LAN966X SoC. GCK generates and supplies clock to various peripherals
+	  within the SoC.
+
 config COMMON_CLK_ASPEED
 	bool "Clock driver for Aspeed BMC SoCs"
 	depends on ARCH_ASPEED || COMPILE_TEST

drivers/clk/Makefile

@@ -37,6 +37,7 @@ obj-$(CONFIG_ARCH_HIGHBANK)		+= clk-highbank.o
 obj-$(CONFIG_CLK_HSDK)			+= clk-hsdk-pll.o
 obj-$(CONFIG_COMMON_CLK_K210)		+= clk-k210.o
 obj-$(CONFIG_LMK04832)			+= clk-lmk04832.o
+obj-$(CONFIG_COMMON_CLK_LAN966X)	+= clk-lan966x.o
 obj-$(CONFIG_COMMON_CLK_LOCHNAGAR)	+= clk-lochnagar.o
 obj-$(CONFIG_COMMON_CLK_MAX77686)	+= clk-max77686.o
 obj-$(CONFIG_COMMON_CLK_MAX9485)	+= clk-max9485.o

drivers/clk/clk-gate.c

@@ -7,6 +7,7 @@
  */
 
 #include <linux/clk-provider.h>
+#include <linux/device.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/io.h>
@@ -222,3 +223,37 @@ void clk_hw_unregister_gate(struct clk_hw *hw)
 	kfree(gate);
 }
 EXPORT_SYMBOL_GPL(clk_hw_unregister_gate);
+
+static void devm_clk_hw_release_gate(struct device *dev, void *res)
+{
+	clk_hw_unregister_gate(*(struct clk_hw **)res);
+}
+
+struct clk_hw *__devm_clk_hw_register_gate(struct device *dev,
+		struct device_node *np, const char *name,
+		const char *parent_name, const struct clk_hw *parent_hw,
+		const struct clk_parent_data *parent_data,
+		unsigned long flags,
+		void __iomem *reg, u8 bit_idx,
+		u8 clk_gate_flags, spinlock_t *lock)
+{
+	struct clk_hw **ptr, *hw;
+
+	ptr = devres_alloc(devm_clk_hw_release_gate, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	hw = __clk_hw_register_gate(dev, np, name, parent_name, parent_hw,
+				    parent_data, flags, reg, bit_idx,
+				    clk_gate_flags, lock);
+
+	if (!IS_ERR(hw)) {
+		*ptr = hw;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return hw;
+}
+EXPORT_SYMBOL_GPL(__devm_clk_hw_register_gate);

drivers/clk/clk-lan966x.c

@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Microchip LAN966x SoC Clock driver.
+ *
+ * Copyright (C) 2021 Microchip Technology, Inc. and its subsidiaries
+ *
+ * Author: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/clock/microchip,lan966x.h>
+
+#define GCK_ENA         BIT(0)
+#define GCK_SRC_SEL     GENMASK(9, 8)
+#define GCK_PRESCALER   GENMASK(23, 16)
+
+#define DIV_MAX		255
+
+static const char *clk_names[N_CLOCKS] = {
+	"qspi0", "qspi1", "qspi2", "sdmmc0",
+	"pi", "mcan0", "mcan1", "flexcom0",
+	"flexcom1", "flexcom2", "flexcom3",
+	"flexcom4", "timer1", "usb_refclk",
+};
+
+struct lan966x_gck {
+	struct clk_hw hw;
+	void __iomem *reg;
+};
+#define to_lan966x_gck(hw) container_of(hw, struct lan966x_gck, hw)
+
+static const struct clk_parent_data lan966x_gck_pdata[] = {
+	{ .fw_name = "cpu", },
+	{ .fw_name = "ddr", },
+	{ .fw_name = "sys", },
+};
+
+static struct clk_init_data init = {
+	.parent_data = lan966x_gck_pdata,
+	.num_parents = ARRAY_SIZE(lan966x_gck_pdata),
+};
+
+struct clk_gate_soc_desc {
+	const char *name;
+	int bit_idx;
+};
+
+static const struct clk_gate_soc_desc clk_gate_desc[] = {
+	{ "uhphs", 11 },
+	{ "udphs", 10 },
+	{ "mcramc", 9 },
+	{ "hmatrix", 8 },
+	{ }
+};
+
+static DEFINE_SPINLOCK(clk_gate_lock);
+static void __iomem *base;
+
+static int lan966x_gck_enable(struct clk_hw *hw)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 val = readl(gck->reg);
+
+	val |= GCK_ENA;
+	writel(val, gck->reg);
+
+	return 0;
+}
+
+static void lan966x_gck_disable(struct clk_hw *hw)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 val = readl(gck->reg);
+
+	val &= ~GCK_ENA;
+	writel(val, gck->reg);
+}
+
+static int lan966x_gck_set_rate(struct clk_hw *hw,
+				unsigned long rate,
+				unsigned long parent_rate)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 div, val = readl(gck->reg);
+
+	if (rate == 0 || parent_rate == 0)
+		return -EINVAL;
+
+	/* Set Prescalar */
+	div = parent_rate / rate;
+	val &= ~GCK_PRESCALER;
+	val |= FIELD_PREP(GCK_PRESCALER, (div - 1));
+	writel(val, gck->reg);
+
+	return 0;
+}
+
+static long lan966x_gck_round_rate(struct clk_hw *hw, unsigned long rate,
+				   unsigned long *parent_rate)
+{
+	unsigned int div;
+
+	if (rate == 0 || *parent_rate == 0)
+		return -EINVAL;
+
+	if (rate >= *parent_rate)
+		return *parent_rate;
+
+	div = DIV_ROUND_CLOSEST(*parent_rate, rate);
+
+	return *parent_rate / div;
+}
+
+static unsigned long lan966x_gck_recalc_rate(struct clk_hw *hw,
+					     unsigned long parent_rate)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 div, val = readl(gck->reg);
+
+	div = FIELD_GET(GCK_PRESCALER, val);
+
+	return parent_rate / (div + 1);
+}
+
+static int lan966x_gck_determine_rate(struct clk_hw *hw,
+				      struct clk_rate_request *req)
+{
+	struct clk_hw *parent;
+	int i;
+
+	for (i = 0; i < clk_hw_get_num_parents(hw); ++i) {
+		parent = clk_hw_get_parent_by_index(hw, i);
+		if (!parent)
+			continue;
+
+		/* Allowed prescaler divider range is 0-255 */
+		if (clk_hw_get_rate(parent) / req->rate <= DIV_MAX) {
+			req->best_parent_hw = parent;
+			req->best_parent_rate = clk_hw_get_rate(parent);
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static u8 lan966x_gck_get_parent(struct clk_hw *hw)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 val = readl(gck->reg);
+
+	return FIELD_GET(GCK_SRC_SEL, val);
+}
+
+static int lan966x_gck_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct lan966x_gck *gck = to_lan966x_gck(hw);
+	u32 val = readl(gck->reg);
+
+	val &= ~GCK_SRC_SEL;
+	val |= FIELD_PREP(GCK_SRC_SEL, index);
+	writel(val, gck->reg);
+
+	return 0;
+}
+
+static const struct clk_ops lan966x_gck_ops = {
+	.enable         = lan966x_gck_enable,
+	.disable        = lan966x_gck_disable,
+	.set_rate       = lan966x_gck_set_rate,
+	.round_rate     = lan966x_gck_round_rate,
+	.recalc_rate    = lan966x_gck_recalc_rate,
+	.determine_rate = lan966x_gck_determine_rate,
+	.set_parent     = lan966x_gck_set_parent,
+	.get_parent     = lan966x_gck_get_parent,
+};
+
+static struct clk_hw *lan966x_gck_clk_register(struct device *dev, int i)
+{
+	struct lan966x_gck *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return ERR_PTR(-ENOMEM);
+
+	priv->reg = base + (i * 4);
+	priv->hw.init = &init;
+	ret = devm_clk_hw_register(dev, &priv->hw);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return &priv->hw;
+};
+
+static int lan966x_gate_clk_register(struct device *dev,
+				     struct clk_hw_onecell_data *hw_data,
+				     void __iomem *gate_base)
+{
+	int i;
+
+	for (i = GCK_GATE_UHPHS; i < N_CLOCKS; ++i) {
+		int idx = i - GCK_GATE_UHPHS;
+
+		hw_data->hws[i] =
+			devm_clk_hw_register_gate(dev, clk_gate_desc[idx].name,
+						  "lan966x", 0, base,
+						  clk_gate_desc[idx].bit_idx,
+						  0, &clk_gate_lock);
+
+		if (IS_ERR(hw_data->hws[i]))
+			return dev_err_probe(dev, PTR_ERR(hw_data->hws[i]),
+					     "failed to register %s clock\n",
+					     clk_gate_desc[idx].name);
+	}
+
+	return 0;
+}
+
+static int lan966x_clk_probe(struct platform_device *pdev)
+{
+	struct clk_hw_onecell_data *hw_data;
+	struct device *dev = &pdev->dev;
+	void __iomem *gate_base;
+	struct resource *res;
+	int i, ret;
+
+	hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, N_CLOCKS),
+			       GFP_KERNEL);
+	if (!hw_data)
+		return -ENOMEM;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	init.ops = &lan966x_gck_ops;
+
+	hw_data->num = GCK_GATE_UHPHS;
+
+	for (i = 0; i < GCK_GATE_UHPHS; i++) {
+		init.name = clk_names[i];
+		hw_data->hws[i] = lan966x_gck_clk_register(dev, i);
+		if (IS_ERR(hw_data->hws[i])) {
+			dev_err(dev, "failed to register %s clock\n",
+				init.name);
+			return PTR_ERR(hw_data->hws[i]);
+		}
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (res) {
+		gate_base = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(gate_base))
+			return PTR_ERR(gate_base);
+
+		hw_data->num = N_CLOCKS;
+
+		ret = lan966x_gate_clk_register(dev, hw_data, gate_base);
+		if (ret)
+			return ret;
+	}
+
+	return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, hw_data);
+}
+
+static const struct of_device_id lan966x_clk_dt_ids[] = {
+	{ .compatible = "microchip,lan966x-gck", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, lan966x_clk_dt_ids);
+
+static struct platform_driver lan966x_clk_driver = {
+	.probe  = lan966x_clk_probe,
+	.driver = {
+		.name = "lan966x-clk",
+		.of_match_table = lan966x_clk_dt_ids,
+	},
+};
+builtin_platform_driver(lan966x_clk_driver);
+
+MODULE_AUTHOR("Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>");
+MODULE_DESCRIPTION("LAN966X clock driver");
+MODULE_LICENSE("GPL v2");

include/dt-bindings/clock/microchip,lan966x.h

@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/*
+ * Copyright (c) 2021 Microchip Inc.
+ *
+ * Author: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
+ */
+
+#ifndef _DT_BINDINGS_CLK_LAN966X_H
+#define _DT_BINDINGS_CLK_LAN966X_H
+
+#define GCK_ID_QSPI0		0
+#define GCK_ID_QSPI1		1
+#define GCK_ID_QSPI2		2
+#define GCK_ID_SDMMC0		3
+#define GCK_ID_PI		4
+#define GCK_ID_MCAN0		5
+#define GCK_ID_MCAN1		6
+#define GCK_ID_FLEXCOM0		7
+#define GCK_ID_FLEXCOM1		8
+#define GCK_ID_FLEXCOM2		9
+#define GCK_ID_FLEXCOM3		10
+#define GCK_ID_FLEXCOM4		11
+#define GCK_ID_TIMER		12
+#define GCK_ID_USB_REFCLK	13
+
+/* Gate clocks */
+#define GCK_GATE_UHPHS		14
+#define GCK_GATE_UDPHS		15
+#define GCK_GATE_MCRAMC		16
+#define GCK_GATE_HMATRIX	17
+
+#define N_CLOCKS		18
+
+#endif

include/linux/clk-provider.h

@@ -490,6 +490,13 @@ struct clk_hw *__clk_hw_register_gate(struct device *dev,
 		unsigned long flags,
 		void __iomem *reg, u8 bit_idx,
 		u8 clk_gate_flags, spinlock_t *lock);
+struct clk_hw *__devm_clk_hw_register_gate(struct device *dev,
+		struct device_node *np, const char *name,
+		const char *parent_name, const struct clk_hw *parent_hw,
+		const struct clk_parent_data *parent_data,
+		unsigned long flags,
+		void __iomem *reg, u8 bit_idx,
+		u8 clk_gate_flags, spinlock_t *lock);
 struct clk *clk_register_gate(struct device *dev, const char *name,
 		const char *parent_name, unsigned long flags,
 		void __iomem *reg, u8 bit_idx,
@@ -544,6 +551,22 @@ struct clk *clk_register_gate(struct device *dev, const char *name,
 	__clk_hw_register_gate((dev), NULL, (name), NULL, NULL, (parent_data), \
 			       (flags), (reg), (bit_idx),		      \
 			       (clk_gate_flags), (lock))
+/**
+ * devm_clk_hw_register_gate - register a gate clock with the clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of this clock's parent
+ * @flags: framework-specific flags for this clock
+ * @reg: register address to control gating of this clock
+ * @bit_idx: which bit in the register controls gating of this clock
+ * @clk_gate_flags: gate-specific flags for this clock
+ * @lock: shared register lock for this clock
+ */
+#define devm_clk_hw_register_gate(dev, name, parent_name, flags, reg, bit_idx,\
+				  clk_gate_flags, lock)			      \
+	__devm_clk_hw_register_gate((dev), NULL, (name), (parent_name), NULL, \
+			       NULL, (flags), (reg), (bit_idx),		      \
+			       (clk_gate_flags), (lock))
 void clk_unregister_gate(struct clk *clk);
 void clk_hw_unregister_gate(struct clk_hw *hw);
 int clk_gate_is_enabled(struct clk_hw *hw);