[v3,4/5] clk: microchip: add PolarFire SoC fabric clock support

diff --git a/drivers/clk/microchip/Makefile b/drivers/clk/microchip/Makefile
index 5fa6dcf30a9a..13250e04e46c 100644
--- a/drivers/clk/microchip/Makefile
+++ b/drivers/clk/microchip/Makefile
@@ -2,3 +2,4 @@ 
 obj-$(CONFIG_COMMON_CLK_PIC32) += clk-core.o
 obj-$(CONFIG_PIC32MZDA) += clk-pic32mzda.o
 obj-$(CONFIG_MCHP_CLK_MPFS) += clk-mpfs.o
+obj-$(CONFIG_MCHP_CLK_MPFS) += clk-mpfs-ccc.o
diff --git a/drivers/clk/microchip/clk-mpfs-ccc.c b/drivers/clk/microchip/clk-mpfs-ccc.c
new file mode 100644
index 000000000000..c776bae981db
--- /dev/null
+++ b/drivers/clk/microchip/clk-mpfs-ccc.c
@@ -0,0 +1,290 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Author: Conor Dooley <conor.dooley@microchip.com>
+ *
+ * Copyright (C) 2022 Microchip Technology Inc. and its subsidiaries
+ */
+#include "asm-generic/errno-base.h"
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/clock/microchip,mpfs-clock.h>
+
+/* address offset of control registers */
+#define MPFS_CCC_PLL_CR			0x04u
+#define MPFS_CCC_REF_CR			0x08u
+#define MPFS_CCC_SSCG_2_CR		0x2Cu
+#define MPFS_CCC_POSTDIV01_CR		0x10u
+#define MPFS_CCC_POSTDIV23_CR		0x14u
+
+#define MPFS_CCC_FBDIV_SHIFT		0x00u
+#define MPFS_CCC_FBDIV_WIDTH		0x0Cu
+#define MPFS_CCC_POSTDIV0_SHIFT		0x08u
+#define MPFS_CCC_POSTDIV1_SHIFT		0x18u
+#define MPFS_CCC_POSTDIV2_SHIFT		MPFS_CCC_POSTDIV0_SHIFT
+#define MPFS_CCC_POSTDIV3_SHIFT		MPFS_CCC_POSTDIV1_SHIFT
+#define MPFS_CCC_POSTDIV_WIDTH		0x06u
+#define MPFS_CCC_REFCLK_SEL		BIT(6)
+#define MPFS_CCC_REFDIV_SHIFT		0x08u
+#define MPFS_CCC_REFDIV_WIDTH		0x06u
+
+#define MPFS_CCC_FIXED_DIV		4
+#define MPFS_CCC_OUTPUTS_PER_PLL	4
+#define MPFS_CCC_REFS_PER_PLL		2
+
+struct mpfs_ccc_data {
+	void __iomem **pll_base;
+	struct device *dev;
+	struct clk_hw_onecell_data hw_data;
+};
+
+struct mpfs_ccc_pll_hw_clock {
+	void __iomem *base;
+	const char *name;
+	const struct clk_parent_data *parents;
+	unsigned int id;
+	u32 reg_offset;
+	u32 shift;
+	u32 width;
+	u32 flags;
+	struct clk_hw hw;
+	struct clk_init_data init;
+};
+
+#define to_mpfs_ccc_clk(_hw) container_of(_hw, struct mpfs_ccc_pll_hw_clock, hw)
+
+/*
+ * mpfs_ccc_lock prevents anything else from writing to a fabric ccc
+ * while a software locked register is being written.
+ */
+static DEFINE_SPINLOCK(mpfs_ccc_lock);
+
+static const struct clk_parent_data mpfs_ccc_pll0_refs[] = {
+	{ .fw_name = "pll0_ref0" },
+	{ .fw_name = "pll0_ref1" },
+};
+
+static const struct clk_parent_data mpfs_ccc_pll1_refs[] = {
+	{ .fw_name = "pll1_ref0" },
+	{ .fw_name = "pll1_ref1" },
+};
+
+static unsigned long mpfs_ccc_pll_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+	struct mpfs_ccc_pll_hw_clock *ccc_hw = to_mpfs_ccc_clk(hw);
+	void __iomem *mult_addr = ccc_hw->base + ccc_hw->reg_offset;
+	void __iomem *ref_div_addr = ccc_hw->base + MPFS_CCC_REF_CR;
+	u32 mult, ref_div;
+
+	mult = readl_relaxed(mult_addr) >> MPFS_CCC_FBDIV_SHIFT;
+	mult &= clk_div_mask(MPFS_CCC_FBDIV_WIDTH);
+	ref_div = readl_relaxed(ref_div_addr) >> MPFS_CCC_REFDIV_SHIFT;
+	ref_div &= clk_div_mask(MPFS_CCC_REFDIV_WIDTH);
+
+	return prate * mult / (ref_div * MPFS_CCC_FIXED_DIV);
+}
+
+static u8 mpfs_ccc_pll_get_parent(struct clk_hw *hw)
+{
+	struct mpfs_ccc_pll_hw_clock *ccc_hw = to_mpfs_ccc_clk(hw);
+	void __iomem *pll_cr_addr = ccc_hw->base + MPFS_CCC_PLL_CR;
+
+	return !!(readl_relaxed(pll_cr_addr) & MPFS_CCC_REFCLK_SEL);
+}
+
+static const struct clk_ops mpfs_ccc_pll_ops = {
+	.recalc_rate = mpfs_ccc_pll_recalc_rate,
+	.get_parent = mpfs_ccc_pll_get_parent,
+};
+
+#define CLK_CCC_PLL(_id, _parents, _shift, _width, _flags, _offset) {		\
+	.id = _id,									\
+	.shift = _shift,								\
+	.width = _width,								\
+	.reg_offset = _offset,								\
+	.flags = _flags,								\
+	.parents = _parents,\
+}
+
+static struct mpfs_ccc_pll_hw_clock mpfs_ccc_pll_clks[] = {
+	CLK_CCC_PLL(CLK_CCC_PLL0, mpfs_ccc_pll0_refs, MPFS_CCC_FBDIV_SHIFT,
+		    MPFS_CCC_FBDIV_WIDTH, 0, MPFS_CCC_SSCG_2_CR),
+	CLK_CCC_PLL(CLK_CCC_PLL1, mpfs_ccc_pll1_refs, MPFS_CCC_FBDIV_SHIFT,
+		    MPFS_CCC_FBDIV_WIDTH, 0, MPFS_CCC_SSCG_2_CR),
+};
+
+struct mpfs_ccc_out_hw_clock {
+	struct clk_divider divider;
+	struct clk_init_data init;
+	unsigned int id;
+	u32 reg_offset;
+};
+
+#define CLK_CCC_OUT(_id, _shift, _width, _flags, _offset) {	\
+	.id = _id,						\
+	.divider.shift = _shift,				\
+	.divider.width = _width,				\
+	.reg_offset = _offset,					\
+	.divider.flags = _flags,				\
+	.divider.lock = &mpfs_ccc_lock,				\
+}
+
+static struct mpfs_ccc_out_hw_clock mpfs_ccc_pll0out_clks[] = {
+	CLK_CCC_OUT(CLK_CCC_PLL0_OUT0, MPFS_CCC_POSTDIV0_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV01_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL0_OUT1, MPFS_CCC_POSTDIV1_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV01_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL0_OUT2, MPFS_CCC_POSTDIV2_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV23_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL0_OUT3, MPFS_CCC_POSTDIV3_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV23_CR),
+};
+
+static struct mpfs_ccc_out_hw_clock mpfs_ccc_pll1out_clks[] = {
+	CLK_CCC_OUT(CLK_CCC_PLL1_OUT0, MPFS_CCC_POSTDIV0_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV01_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL1_OUT1, MPFS_CCC_POSTDIV1_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV01_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL1_OUT2, MPFS_CCC_POSTDIV2_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV23_CR),
+	CLK_CCC_OUT(CLK_CCC_PLL1_OUT3, MPFS_CCC_POSTDIV3_SHIFT, MPFS_CCC_POSTDIV_WIDTH,
+		    CLK_DIVIDER_ONE_BASED, MPFS_CCC_POSTDIV23_CR),
+};
+
+static struct mpfs_ccc_out_hw_clock *mpfs_ccc_pllout_clks[] = {
+	mpfs_ccc_pll0out_clks, mpfs_ccc_pll1out_clks
+};
+
+static int mpfs_ccc_register_outputs(struct device *dev, struct mpfs_ccc_out_hw_clock *out_hws,
+				     unsigned int num_clks, struct mpfs_ccc_data *data,
+				     struct mpfs_ccc_pll_hw_clock *parent)
+{
+	int ret;
+
+	for (unsigned int i = 0; i < num_clks; i++) {
+		struct mpfs_ccc_out_hw_clock *out_hw = &out_hws[i];
+		char *name = devm_kzalloc(dev, 23, GFP_KERNEL);
+
+		snprintf(name, 23, "%s_out%u", parent->name, i);
+		out_hw->divider.hw.init = CLK_HW_INIT_HW(name, &parent->hw, &clk_divider_ops, 0);
+		out_hw->divider.reg = data->pll_base[i / MPFS_CCC_OUTPUTS_PER_PLL] +
+			out_hw->reg_offset;
+
+		ret = devm_clk_hw_register(dev, &out_hw->divider.hw);
+		if (ret)
+			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
+					     out_hw->id);
+
+		data->hw_data.hws[out_hw->id] = &out_hw->divider.hw;
+	}
+
+	return 0;
+}
+
+#define CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(_name, _parents, _ops, _flags)	\
+	(&(struct clk_init_data) {						\
+		.flags		= _flags,					\
+		.name		= _name,					\
+		.parent_data	= _parents,					\
+		.num_parents	= MPFS_CCC_REFS_PER_PLL,			\
+		.ops		= _ops,						\
+	})
+
+static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clock *pll_hws,
+				  unsigned int num_clks, struct mpfs_ccc_data *data)
+{
+	int ret;
+
+	for (unsigned int i = 0; i < num_clks; i++) {
+		struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
+		char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
+
+		pll_hw->base = data->pll_base[i];
+		snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
+		pll_hw->name = (const char *)name;
+		pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
+								      pll_hw->parents,
+								      &mpfs_ccc_pll_ops, 0);
+
+		ret = devm_clk_hw_register(dev, &pll_hw->hw);
+		if (ret)
+			return dev_err_probe(dev, ret, "failed to register ccc id: %d\n",
+					     pll_hw->id);
+
+		data->hw_data.hws[pll_hw->id] = &pll_hw->hw;
+
+		ret = mpfs_ccc_register_outputs(dev, mpfs_ccc_pllout_clks[i],
+						MPFS_CCC_OUTPUTS_PER_PLL, data, pll_hw);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int mpfs_ccc_probe(struct platform_device *pdev)
+{
+	struct mpfs_ccc_data *clk_data;
+	void __iomem *pll_base[ARRAY_SIZE(mpfs_ccc_pll_clks)];
+	unsigned int num_clks;
+	int ret;
+
+	num_clks = ARRAY_SIZE(mpfs_ccc_pll_clks) + ARRAY_SIZE(mpfs_ccc_pll0out_clks)
+		+ ARRAY_SIZE(mpfs_ccc_pll1out_clks);
+
+	clk_data = devm_kzalloc(&pdev->dev, struct_size(clk_data, hw_data.hws, num_clks),
+				GFP_KERNEL);
+	if (!clk_data)
+		return -ENOMEM;
+
+	pll_base[0] = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(pll_base[0]))
+		return PTR_ERR(pll_base[0]);
+
+	pll_base[1] = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(pll_base[1]))
+		return PTR_ERR(pll_base[1]);
+
+	clk_data->pll_base = pll_base;
+	clk_data->hw_data.num = num_clks;
+	clk_data->dev = &pdev->dev;
+
+	ret = mpfs_ccc_register_plls(clk_data->dev, mpfs_ccc_pll_clks,
+				     ARRAY_SIZE(mpfs_ccc_pll_clks), clk_data);
+	if (ret)
+		return ret;
+
+	return devm_of_clk_add_hw_provider(clk_data->dev, of_clk_hw_onecell_get,
+					   &clk_data->hw_data);
+}
+
+static const struct of_device_id mpfs_ccc_of_match_table[] = {
+	{ .compatible = "microchip,mpfs-ccc", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mpfs_ccc_of_match_table);
+
+static struct platform_driver mpfs_ccc_driver = {
+	.probe = mpfs_ccc_probe,
+	.driver	= {
+		.name = "microchip-mpfs-ccc",
+		.of_match_table = mpfs_ccc_of_match_table,
+	},
+};
+
+static int __init clk_ccc_init(void)
+{
+	return platform_driver_register(&mpfs_ccc_driver);
+}
+core_initcall(clk_ccc_init);
+
+static void __exit clk_ccc_exit(void)
+{
+	platform_driver_unregister(&mpfs_ccc_driver);
+}
+module_exit(clk_ccc_exit);
+
+MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Conditioning Circuitry Driver");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_LICENSE("GPL");