clk: nuvoton: Add support for NPCM750

Add clock controller driver for NPCM750

Signed-off-by: Jim Liu <JJLIU0@nuvoton.com>
Signed-off-by: Stanley Chu <yschu@nuvoton.com>
Reviewed-by: Sean Anderson <seanga2@gmail.com>

5 files changed, 502 insertions, 0 deletions

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index bb4eee5d99..f5b553172c 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_ARCH_ASPEED) += aspeed/
 obj-$(CONFIG_ARCH_MEDIATEK) += mediatek/
 obj-$(CONFIG_ARCH_MESON) += meson/
 obj-$(CONFIG_ARCH_MTMIPS) += mtmips/
+obj-$(CONFIG_ARCH_NPCM) += nuvoton/
 obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
 obj-$(CONFIG_ARCH_SOCFPGA) += altera/
 obj-$(CONFIG_ARCH_SUNXI) += sunxi/
diff --git a/drivers/clk/nuvoton/Makefile b/drivers/clk/nuvoton/Makefile
new file mode 100644
index 0000000000..c63d9c16f1
--- /dev/null
+++ b/drivers/clk/nuvoton/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_ARCH_NPCM) += clk_npcm.o
+obj-$(CONFIG_ARCH_NPCM7xx) += clk_npcm7xx.o
diff --git a/drivers/clk/nuvoton/clk_npcm.c b/drivers/clk/nuvoton/clk_npcm.c
new file mode 100644
index 0000000000..8d71f2a24b
--- /dev/null
+++ b/drivers/clk/nuvoton/clk_npcm.c
@@ -0,0 +1,299 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2022 Nuvoton Technology Corp.
+ *
+ * Formula for calculating clock rate:
+ * Fout = ((Fin / PRE_DIV) / div) / POST_DIV
+ */
+
+#include <div64.h>
+#include <dm.h>
+#include <asm/io.h>
+#include <linux/bitfield.h>
+#include <linux/log2.h>
+#include "clk_npcm.h"
+
+static int clkid_to_clksel(struct npcm_clk_select *selector, int id)
+{
+	int i;
+
+	for (i = 0; i < selector->num_parents; i++) {
+		if (selector->parents[i].id == id)
+			return selector->parents[i].clksel;
+	}
+
+	return -EINVAL;
+}
+
+static int clksel_to_clkid(struct npcm_clk_select *selector, int clksel)
+{
+	int i;
+
+	for (i = 0; i < selector->num_parents; i++) {
+		if (selector->parents[i].clksel == clksel)
+			return selector->parents[i].id;
+	}
+
+	return -EINVAL;
+}
+
+static struct npcm_clk_pll *npcm_clk_pll_get(struct npcm_clk_data *clk_data, int id)
+{
+	struct npcm_clk_pll *pll = clk_data->clk_plls;
+	int i;
+
+	for (i = 0; i < clk_data->num_plls; i++) {
+		if (pll->id == id)
+			return pll;
+		pll++;
+	}
+
+	return NULL;
+}
+
+static struct npcm_clk_select *npcm_clk_selector_get(struct npcm_clk_data *clk_data,
+						     int id)
+{
+	struct npcm_clk_select *selector = clk_data->clk_selectors;
+	int i;
+
+	for (i = 0; i < clk_data->num_selectors; i++) {
+		if (selector->id == id)
+			return selector;
+		selector++;
+	}
+
+	return NULL;
+}
+
+static struct npcm_clk_div *npcm_clk_divider_get(struct npcm_clk_data *clk_data,
+						 int id)
+{
+	struct npcm_clk_div *divider = clk_data->clk_dividers;
+	int i;
+
+	for (i = 0; i < clk_data->num_dividers; i++) {
+		if (divider->id == id)
+			return divider;
+		divider++;
+	}
+
+	return NULL;
+}
+
+static ulong npcm_clk_get_fin(struct clk *clk)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_select *selector;
+	struct clk parent;
+	ulong parent_rate;
+	u32 val, clksel;
+	int ret;
+
+	selector = npcm_clk_selector_get(priv->clk_data, clk->id);
+	if (!selector)
+		return 0;
+
+	if (selector->flags & FIXED_PARENT) {
+		clksel = 0;
+	} else {
+		val = readl(priv->base + selector->reg);
+		clksel = (val & selector->mask) >> (ffs(selector->mask) - 1);
+	}
+	parent.id = clksel_to_clkid(selector, clksel);
+
+	ret = clk_request(clk->dev, &parent);
+	if (ret)
+		return 0;
+
+	parent_rate = clk_get_rate(&parent);
+
+	debug("fin of clk%lu = %lu\n", clk->id, parent_rate);
+	return parent_rate;
+}
+
+static u32 npcm_clk_get_div(struct clk *clk)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_div *divider;
+	u32 val, div;
+
+	divider = npcm_clk_divider_get(priv->clk_data, clk->id);
+	if (!divider)
+		return 0;
+
+	val = readl(priv->base + divider->reg);
+	div = (val & divider->mask) >> (ffs(divider->mask) - 1);
+	if (divider->flags & DIV_TYPE1)
+		div = div + 1;
+	else
+		div = 1 << div;
+
+	if (divider->flags & PRE_DIV2)
+		div = div << 1;
+
+	return div;
+}
+
+static u32 npcm_clk_set_div(struct clk *clk, u32 div)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_div *divider;
+	u32 val, clkdiv;
+
+	divider = npcm_clk_divider_get(priv->clk_data, clk->id);
+	if (!divider)
+		return -EINVAL;
+
+	if (divider->flags & PRE_DIV2)
+		div = div >> 1;
+
+	if (divider->flags & DIV_TYPE1)
+		clkdiv = div - 1;
+	else
+		clkdiv = ilog2(div);
+
+	val = readl(priv->base + divider->reg);
+	val &= ~divider->mask;
+	val |= (clkdiv << (ffs(divider->mask) - 1)) & divider->mask;
+	writel(val, priv->base + divider->reg);
+
+	return 0;
+}
+
+static ulong npcm_clk_get_fout(struct clk *clk)
+{
+	ulong parent_rate;
+	u32 div;
+
+	parent_rate = npcm_clk_get_fin(clk);
+	if (!parent_rate)
+		return -EINVAL;
+
+	div = npcm_clk_get_div(clk);
+	if (!div)
+		return -EINVAL;
+
+	debug("fout of clk%lu = (%lu / %u)\n", clk->id, parent_rate, div);
+	return (parent_rate / div);
+}
+
+static ulong npcm_clk_get_pll_fout(struct clk *clk)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_pll *pll;
+	struct clk parent;
+	ulong parent_rate;
+	ulong fbdv, indv, otdv1, otdv2;
+	u32 val;
+	u64 ret;
+
+	pll = npcm_clk_pll_get(priv->clk_data, clk->id);
+	if (!pll)
+		return -ENODEV;
+
+	parent.id = pll->parent_id;
+	ret = clk_request(clk->dev, &parent);
+	if (ret)
+		return ret;
+
+	parent_rate = clk_get_rate(&parent);
+
+	val = readl(priv->base + pll->reg);
+	indv = FIELD_GET(PLLCON_INDV, val);
+	fbdv = FIELD_GET(PLLCON_FBDV, val);
+	otdv1 = FIELD_GET(PLLCON_OTDV1, val);
+	otdv2 = FIELD_GET(PLLCON_OTDV2, val);
+
+	ret = (u64)parent_rate * fbdv;
+	do_div(ret, indv * otdv1 * otdv2);
+	if (pll->flags & POST_DIV2)
+		do_div(ret, 2);
+
+	debug("fout of pll(id %lu) = %llu\n", clk->id, ret);
+	return ret;
+}
+
+static ulong npcm_clk_get_rate(struct clk *clk)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_data *clk_data = priv->clk_data;
+	struct clk refclk;
+	int ret;
+
+	debug("%s: id %lu\n", __func__, clk->id);
+	if (clk->id == clk_data->refclk_id) {
+		ret = clk_get_by_name(clk->dev, "refclk", &refclk);
+		if (!ret)
+			return clk_get_rate(&refclk);
+		else
+			return ret;
+	}
+
+	if (clk->id >= clk_data->pll0_id &&
+	    clk->id < clk_data->pll0_id + clk_data->num_plls)
+		return npcm_clk_get_pll_fout(clk);
+	else
+		return npcm_clk_get_fout(clk);
+}
+
+static ulong npcm_clk_set_rate(struct clk *clk, ulong rate)
+{
+	ulong parent_rate;
+	u32 div;
+	int ret;
+
+	debug("%s: id %lu, rate %lu\n", __func__, clk->id, rate);
+	parent_rate = npcm_clk_get_fin(clk);
+	if (!parent_rate)
+		return -EINVAL;
+
+	div = DIV_ROUND_UP(parent_rate, rate);
+	ret = npcm_clk_set_div(clk, div);
+	if (ret)
+		return ret;
+
+	debug("%s: rate %lu, new rate (%lu / %u)\n", __func__, rate, parent_rate, div);
+	return (parent_rate / div);
+}
+
+static int npcm_clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+	struct npcm_clk_select *selector;
+	int clksel;
+	u32 val;
+
+	debug("%s: id %lu, parent %lu\n", __func__, clk->id, parent->id);
+	selector = npcm_clk_selector_get(priv->clk_data, clk->id);
+	if (!selector)
+		return -EINVAL;
+
+	clksel = clkid_to_clksel(selector, parent->id);
+	if (clksel < 0)
+		return -EINVAL;
+
+	val = readl(priv->base + selector->reg);
+	val &= ~selector->mask;
+	val |= clksel << (ffs(selector->mask) - 1);
+	writel(val, priv->base + selector->reg);
+
+	return 0;
+}
+
+static int npcm_clk_request(struct clk *clk)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(clk->dev);
+
+	if (clk->id >= priv->num_clks)
+		return -EINVAL;
+
+	return 0;
+}
+
+const struct clk_ops npcm_clk_ops = {
+	.get_rate = npcm_clk_get_rate,
+	.set_rate = npcm_clk_set_rate,
+	.set_parent = npcm_clk_set_parent,
+	.request = npcm_clk_request,
+};
diff --git a/drivers/clk/nuvoton/clk_npcm.h b/drivers/clk/nuvoton/clk_npcm.h
new file mode 100644
index 0000000000..06b60dc8b8
--- /dev/null
+++ b/drivers/clk/nuvoton/clk_npcm.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _CLK_NPCM_H_
+#define _CLK_NPCM_H_
+
+#include <clk-uclass.h>
+
+/* Register offsets */
+#define CLKSEL		0x04	/* clock source selection */
+#define CLKDIV1		0x08	/* clock divider 1 */
+#define CLKDIV2		0x2C	/* clock divider 2 */
+#define CLKDIV3		0x58	/* clock divider 3 */
+#define PLLCON0		0x0C	/* pll0 control */
+#define PLLCON1		0x10	/* pll1 control */
+#define PLLCON2		0x54	/* pll2 control */
+
+/* CLKSEL bit filed */
+#define NPCM7XX_CPUCKSEL	GENMASK(1, 0)
+#define NPCM8XX_CPUCKSEL	GENMASK(2, 0)
+#define SDCKSEL		GENMASK(7, 6)
+#define UARTCKSEL	GENMASK(9, 8)
+#define TIMCKSEL	GENMASK(15, 14)
+
+/* CLKDIV1 bit filed */
+#define SPI3CKDIV	GENMASK(10, 6)
+#define MMCCKDIV	GENMASK(15, 11)
+#define UARTDIV1	GENMASK(20, 16)
+#define TIMCKDIV	GENMASK(25, 21)
+#define CLK4DIV		GENMASK(27, 26)
+
+/* CLKDIV2 bit filed */
+#define APB5CKDIV	GENMASK(23, 22)
+#define APB2CKDIV	GENMASK(27, 26)
+
+/* CLKDIV3 bit filed */
+#define SPIXCKDIV	GENMASK(5, 1)
+#define SPI0CKDIV	GENMASK(10, 6)
+#define UARTDIV2	GENMASK(15, 11)
+#define SPI1CKDIV	GENMASK(23, 16)
+
+/* PLLCON bit filed */
+#define PLLCON_INDV	GENMASK(5, 0)
+#define PLLCON_OTDV1	GENMASK(10, 8)
+#define PLLCON_OTDV2	GENMASK(15, 13)
+#define PLLCON_FBDV	GENMASK(27, 16)
+
+/* Flags */
+#define DIV_TYPE1	BIT(0)	/* div = clkdiv + 1 */
+#define DIV_TYPE2	BIT(1)	/* div = 1 << clkdiv */
+#define PRE_DIV2	BIT(2)	/* Pre divisor = 2 */
+#define POST_DIV2	BIT(3)	/* Post divisor = 2 */
+#define FIXED_PARENT	BIT(4)	/* clock source is fixed */
+
+/* Parameters of PLL configuration */
+struct npcm_clk_pll {
+	const int id;
+	const int parent_id;
+	u32 reg;
+	u32 flags;
+};
+
+/* Parent clock id to clksel mapping */
+struct parent_data {
+	int id;
+	int clksel;
+};
+
+/* Parameters of parent selection */
+struct npcm_clk_select {
+	const int id;
+	const struct parent_data *parents;
+	u32 reg;
+	u32 mask;
+	u8 num_parents;
+	u32 flags;
+};
+
+/* Parameters of clock divider */
+struct npcm_clk_div {
+	const int id;
+	u32 reg;
+	u32 mask;
+	u32 flags;
+};
+
+struct npcm_clk_data {
+	struct npcm_clk_pll *clk_plls;
+	int num_plls;
+	struct npcm_clk_select *clk_selectors;
+	int num_selectors;
+	struct npcm_clk_div *clk_dividers;
+	int num_dividers;
+	int refclk_id;
+	int pll0_id;
+};
+
+struct npcm_clk_priv {
+	void __iomem *base;
+	struct npcm_clk_data *clk_data;
+	int num_clks;
+};
+
+extern const struct clk_ops npcm_clk_ops;
+
+#endif
diff --git a/drivers/clk/nuvoton/clk_npcm7xx.c b/drivers/clk/nuvoton/clk_npcm7xx.c
new file mode 100644
index 0000000000..a12aaa2f4c
--- /dev/null
+++ b/drivers/clk/nuvoton/clk_npcm7xx.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2021 Nuvoton Technology Corp.
+ */
+
+#include <dm.h>
+#include <dt-bindings/clock/nuvoton,npcm7xx-clock.h>
+#include "clk_npcm.h"
+
+/* Parent clock map */
+static const struct parent_data pll_parents[] = {
+	{NPCM7XX_CLK_PLL0, 0},
+	{NPCM7XX_CLK_PLL1, 1},
+	{NPCM7XX_CLK_REFCLK, 2},
+	{NPCM7XX_CLK_PLL2DIV2, 3}
+};
+
+static const struct parent_data cpuck_parents[] = {
+	{NPCM7XX_CLK_PLL0, 0},
+	{NPCM7XX_CLK_PLL1, 1},
+	{NPCM7XX_CLK_REFCLK, 2},
+};
+
+static const struct parent_data apb_parent[] = {{NPCM7XX_CLK_AHB, 0}};
+
+static struct npcm_clk_pll npcm7xx_clk_plls[] = {
+	{NPCM7XX_CLK_PLL0, NPCM7XX_CLK_REFCLK, PLLCON0, 0},
+	{NPCM7XX_CLK_PLL1, NPCM7XX_CLK_REFCLK, PLLCON1, 0},
+	{NPCM7XX_CLK_PLL2, NPCM7XX_CLK_REFCLK, PLLCON2, 0},
+	{NPCM7XX_CLK_PLL2DIV2, NPCM7XX_CLK_REFCLK, PLLCON2, POST_DIV2}
+};
+
+static struct npcm_clk_select npcm7xx_clk_selectors[] = {
+	{NPCM7XX_CLK_AHB, cpuck_parents, CLKSEL, NPCM7XX_CPUCKSEL, 3, 0},
+	{NPCM7XX_CLK_APB2, apb_parent, 0, 0, 1, FIXED_PARENT},
+	{NPCM7XX_CLK_APB5, apb_parent, 0, 0, 1, FIXED_PARENT},
+	{NPCM7XX_CLK_SPI0, apb_parent, 0, 0, 1, FIXED_PARENT},
+	{NPCM7XX_CLK_SPI3, apb_parent, 0, 0, 1, FIXED_PARENT},
+	{NPCM7XX_CLK_SPIX, apb_parent, 0, 0, 1, FIXED_PARENT},
+	{NPCM7XX_CLK_UART, pll_parents, CLKSEL, UARTCKSEL, 4, 0},
+	{NPCM7XX_CLK_TIMER, pll_parents, CLKSEL, TIMCKSEL, 4, 0},
+	{NPCM7XX_CLK_SDHC, pll_parents, CLKSEL, SDCKSEL, 4, 0}
+};
+
+static struct npcm_clk_div npcm7xx_clk_dividers[] = {
+	{NPCM7XX_CLK_AHB, CLKDIV1, CLK4DIV, DIV_TYPE1 | PRE_DIV2},
+	{NPCM7XX_CLK_APB2, CLKDIV2, APB2CKDIV, DIV_TYPE2},
+	{NPCM7XX_CLK_APB5, CLKDIV2, APB5CKDIV, DIV_TYPE2},
+	{NPCM7XX_CLK_SPI0, CLKDIV3, SPI0CKDIV, DIV_TYPE1},
+	{NPCM7XX_CLK_SPI3, CLKDIV1, SPI3CKDIV, DIV_TYPE1},
+	{NPCM7XX_CLK_SPIX, CLKDIV3, SPIXCKDIV, DIV_TYPE1},
+	{NPCM7XX_CLK_UART, CLKDIV1, UARTDIV1, DIV_TYPE1},
+	{NPCM7XX_CLK_TIMER, CLKDIV1, TIMCKDIV, DIV_TYPE2},
+	{NPCM7XX_CLK_SDHC, CLKDIV1, MMCCKDIV, DIV_TYPE1}
+};
+
+static struct npcm_clk_data npcm7xx_clk_data = {
+	.clk_plls = npcm7xx_clk_plls,
+	.num_plls = ARRAY_SIZE(npcm7xx_clk_plls),
+	.clk_selectors = npcm7xx_clk_selectors,
+	.num_selectors = ARRAY_SIZE(npcm7xx_clk_selectors),
+	.clk_dividers = npcm7xx_clk_dividers,
+	.num_dividers = ARRAY_SIZE(npcm7xx_clk_dividers),
+	.refclk_id = NPCM7XX_CLK_REFCLK,
+	.pll0_id = NPCM7XX_CLK_PLL0,
+};
+
+static int npcm7xx_clk_probe(struct udevice *dev)
+{
+	struct npcm_clk_priv *priv = dev_get_priv(dev);
+
+	priv->base = dev_read_addr_ptr(dev);
+	if (!priv->base)
+		return -EINVAL;
+
+	priv->clk_data = &npcm7xx_clk_data;
+	priv->num_clks = NPCM7XX_NUM_CLOCKS;
+
+	return 0;
+}
+
+static const struct udevice_id npcm7xx_clk_ids[] = {
+	{ .compatible = "nuvoton,npcm750-clk" },
+	{ }
+};
+
+U_BOOT_DRIVER(clk_npcm) = {
+	.name           = "clk_npcm",
+	.id             = UCLASS_CLK,
+	.of_match       = npcm7xx_clk_ids,
+	.ops            = &npcm_clk_ops,
+	.priv_auto	= sizeof(struct npcm_clk_priv),
+	.probe          = npcm7xx_clk_probe,
+	.flags = DM_FLAG_PRE_RELOC,
+};