[RFC 3/4] clk: Add Realtek RTD1295

[Andreas FÃrber]

Add two clock controller drivers for RTD1295.

Clock names are taken from vendor DT and clk_summary where possible.
Clock rate calculations are guesses derived from Android register values and
resulting rates in clk_summary.
Clock gate parents are mostly unknown - osc27M is chosen for UART baudrate.

Signed-off-by: Andreas FÃrber <afaerber@xxxxxxx>
---
 drivers/clk/Kconfig       |   7 +
 drivers/clk/Makefile      |   1 +
 drivers/clk/clk-rtd1295.c | 385 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 393 insertions(+)
 create mode 100644 drivers/clk/clk-rtd1295.c

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index a874b72612d0..8e4534912f51 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -209,6 +209,13 @@ config COMMON_CLK_OXNAS
 	---help---
 	  Support for the OXNAS SoC Family clocks.
 
+config CLK_RTD129X
+	bool "Clock driver for the Realtek RTD129x SoC family"
+	default ARCH_REALTEK && ARM64
+	depends on (ARCH_REALTEK && ARM64) || COMPILE_TEST
+	---help---
+	  Support for the Realtek RTD1295 SoC.
+
 config COMMON_CLK_VC5
 	tristate "Clock driver for IDT VersaClock 5,6 devices"
 	depends on I2C
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index cd376b3fb47a..466965452d4f 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_COMMON_CLK_PALMAS)		+= clk-palmas.o
 obj-$(CONFIG_COMMON_CLK_PWM)		+= clk-pwm.o
 obj-$(CONFIG_CLK_QORIQ)			+= clk-qoriq.o
 obj-$(CONFIG_COMMON_CLK_RK808)		+= clk-rk808.o
+obj-$(CONFIG_CLK_RTD129X)		+= clk-rtd1295.o
 obj-$(CONFIG_COMMON_CLK_HI655X)		+= clk-hi655x.o
 obj-$(CONFIG_COMMON_CLK_S2MPS11)	+= clk-s2mps11.o
 obj-$(CONFIG_COMMON_CLK_SCPI)           += clk-scpi.o
diff --git a/drivers/clk/clk-rtd1295.c b/drivers/clk/clk-rtd1295.c
new file mode 100644
index 000000000000..a20e71460dac
--- /dev/null
+++ b/drivers/clk/clk-rtd1295.c
@@ -0,0 +1,385 @@
+/*
+ * Realtek RTD1295
+ *
+ * Copyright (c) 2017 Andreas FÃrber
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <dt-bindings/clock/realtek,rtd1295.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+struct rtd_pll_clk {
+	struct clk_hw hw;
+	void __iomem *base;
+	bool gpu;
+};
+
+#define to_pll_clk(_hw) container_of(_hw, struct rtd_pll_clk, hw)
+
+static unsigned long rtd_scpu_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+	struct rtd_pll_clk *pll = to_pll_clk(hw);
+	u32 reg1, reg2, reg3, reg4;
+	unsigned f1, f2, f3, f4, f5;
+	unsigned long rate, frac;
+
+	reg1 = readl(pll->base + 0x4);
+	reg2 = readl(pll->base - (0x500 - 0x30));
+	reg3 = readl(pll->base + 0x0);
+	reg4 = readl(pll->base + 0x1c);
+	f1 = (reg1 >> 11) & 0xff;
+	f2 = (reg1 >> 0) & 0x7ff;
+	f3 = (reg2 >> 7) & 0x3;
+	f4 = (reg3 >> 0) & 0x1;
+	f5 = (reg4 >> 20) & 0x1;
+
+	rate = parent_rate * (f1 + 3) / f3;
+	frac = parent_rate / 2048 * f2 / BIT(f4);
+	rate += frac;
+
+	pr_info("%s 0x%08x n=%u f=%u 0x%08x x=%u 0x%08x y=%u 0x%08x z=%u rate=%lu\n",
+		__clk_get_name(hw->clk),
+		reg1, f1, f2,
+		reg2, f3,
+		reg3, f4,
+		reg4, f5, rate);
+	return rate;
+}
+
+static const struct clk_ops rtd_scpu_ops = {
+	.recalc_rate = rtd_scpu_recalc_rate,
+};
+
+static struct clk *rtd_scpu(void __iomem *base, const char *name, struct clk *parent)
+{
+	struct rtd_pll_clk *pll;
+	struct clk_init_data init;
+	struct clk *clk;
+	const char *parents[1];
+
+	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return ERR_PTR(-ENOMEM);
+
+	if (parent)
+		parents[0] = __clk_get_name(parent);
+	init.name = name;
+	init.ops = &rtd_scpu_ops;
+	init.parent_names = parent ? parents : NULL;
+	init.num_parents = parent ? 1 : 0;
+	init.flags = CLK_IGNORE_UNUSED;
+
+	pll->hw.init = &init;
+	pll->base = base;
+
+	clk = clk_register(NULL, &pll->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: error registering clk", name);
+		kfree(pll);
+	}
+	return clk;
+}
+
+static unsigned long rtd_nf_ssc_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+	struct rtd_pll_clk *pll = to_pll_clk(hw);
+	u32 reg1, reg2, reg3;
+	unsigned f1, f2, f3, f4;
+	unsigned long rate, frac;
+
+	reg1 = readl(pll->base + 0x4);
+	reg2 = readl(pll->base + 0x0);
+	reg3 = readl(pll->base + 0x1c);
+	f1 = (reg1 >> 11) & 0xff;
+	f2 = (reg1 >> 0) & 0x7ff;
+	f3 = (reg2 >> 0) & 0xf;
+	f4 = (reg3 >> 20) & 0x1;
+
+	rate = parent_rate * (f1 + 3);
+	if (pll->gpu) {
+		rate /= 2;
+	}
+	frac = parent_rate * 4 * f2 / BIT(f3);
+	if (pll->gpu) {
+		frac /= 2;
+	}
+	rate += frac;
+
+	pr_info("%s 0x%08x n=%u f=%u 0x%08x d=%u 0x%08x x=%u rate=%lu\n", __clk_get_name(hw->clk),
+		reg1, f1, f2,
+		reg2, f3,
+		reg3, f4, rate);
+	return rate;
+}
+
+static const struct clk_ops rtd_nf_ssc_ops = {
+	.recalc_rate = rtd_nf_ssc_recalc_rate,
+};
+
+static struct clk *rtd_nf_ssc(void __iomem *base, const char *name, struct clk *parent)
+{
+	struct rtd_pll_clk *pll;
+	struct clk_init_data init;
+	struct clk *clk;
+	const char *parents[1];
+
+	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return ERR_PTR(-ENOMEM);
+
+	if (parent)
+		parents[0] = __clk_get_name(parent);
+	init.name = name;
+	init.ops = &rtd_nf_ssc_ops;
+	init.parent_names = parent ? parents : NULL;
+	init.num_parents = parent ? 1 : 0;
+	init.flags = CLK_IGNORE_UNUSED;
+
+	pll->hw.init = &init;
+	pll->base = base;
+	pll->gpu = (strcmp(name, "pll_gpu") == 0);
+
+	clk = clk_register(NULL, &pll->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: error registering clk", name);
+		kfree(pll);
+	}
+	return clk;
+}
+
+static unsigned long rtd_mno_ctrl_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+	struct rtd_pll_clk *pll = to_pll_clk(hw);
+	u32 reg1, reg2;
+	unsigned f1, f2, f3;
+	unsigned long rate;
+
+	reg1 = readl(pll->base + 0x0);
+	reg2 = readl(pll->base + 0x4);
+	f1 = (reg1 >> 4) & 0xff;
+	f2 = (reg1 >> 12) & 0x3;
+	f3 = (reg1 >> 17) & 0x3;
+
+	rate = parent_rate * (f1 + 2) / (f2 +1) / (f3 + 1);
+
+	pr_info("%s 0x%08x m=%u n=%u o=%u 0x%08x rate=%lu\n", __clk_get_name(hw->clk),
+		reg1, f1, f2, f3,
+		reg2, rate);
+	return rate;
+}
+
+static const struct clk_ops rtd_mno_ctrl_ops = {
+	.recalc_rate = rtd_mno_ctrl_recalc_rate,
+};
+
+static struct clk *rtd_mno_ctrl(void __iomem *base, const char *name, struct clk *parent)
+{
+	struct rtd_pll_clk *pll;
+	struct clk_init_data init;
+	struct clk *clk;
+	const char *parents[1];
+
+	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return ERR_PTR(-ENOMEM);
+
+	if (parent)
+		parents[0] = __clk_get_name(parent);
+	init.name = name;
+	init.ops = &rtd_mno_ctrl_ops;
+	init.parent_names = parent ? parents : NULL;
+	init.num_parents = parent ? 1 : 0;
+	init.flags = CLK_IGNORE_UNUSED;
+
+	pll->hw.init = &init;
+	pll->base = base;
+
+	clk = clk_register(NULL, &pll->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: error registering clk", name);
+		kfree(pll);
+	}
+	return clk;
+}
+
+static const char * const rtd1295_gates1[32] = {
+	[ 0] = "clk_en_misc",
+	[ 1] = "clk_en_pcie0",
+	[ 2] = "clk_en_sata_0",
+	[ 3] = "clk_en_gspi",
+	[ 4] = "clk_en_usb",
+	[ 5] = "clk_en_pcr",
+	[ 6] = "clk_en_iso_misc",
+	[ 7] = "clk_en_sata_alive_0",
+	[ 8] = "clk_en_hdmi",
+	[ 9] = "clk_en_etn",
+	[10] = "clk_en_aio",
+	/* "*clk_en_gpu", */
+	/* "*clk_en_ve1", */
+	/* "*clk_en_ve2", */
+	[14] = "clk_en_tve",
+	/* "*clk_en_vo", */
+	[16] = "clk_en_lvds",
+	[17] = "clk_en_se",
+	[18] = "clk_en_dcu",
+	[19] = "clk_en_cp",
+	[20] = "clk_en_md",
+	[21] = "clk_en_tp",
+	[22] = "clk_en_rsa",
+	[23] = "clk_en_nf",
+	[24] = "clk_en_emmc",
+	[25] = "clk_en_cr",
+	[26] = "clk_en_sdio_ip",
+	[27] = "clk_en_mipi",
+	[28] = "clk_en_emmc_ip",
+	/* "*clk_en_ve3", */
+	[30] = "clk_en_sdio",
+	[31] = "clk_en_sd_ip",
+};
+
+static const char * const rtd1295_gates2[32] = {
+	[ 0] = "clk_en_nat",
+	[ 1] = "clk_en_misc_i2c_5",
+	/* "*clk_en_scpu", */
+	[ 3] = "clk_en_jpeg",
+	/* "*clk_en_apu", */
+	[ 5] = "clk_en_pcie1",
+	[ 6] = "clk_en_misc_sc",
+	[ 7] = "clk_en_cbus_tx",
+	/* "*rvd", */
+	/* "*rvd", */
+	[10] = "clk_en_misc_rtc",
+	/* "*rvd", */
+	/* "*rvd", */
+	[13] = "clk_en_misc_i2c_4",
+	[14] = "clk_en_misc_i2c_3",
+	[15] = "clk_en_misc_i2c_2",
+	[16] = "clk_en_misc_i2c_1",
+	[17] = "clk_en_aio_au_codec",
+	[18] = "clk_en_aio_mod",
+	[19] = "clk_en_aio_da",
+	[20] = "clk_en_aio_hdmi",
+	[21] = "clk_en_aio_spdif",
+	[22] = "clk_en_aio_i2s",
+	[23] = "clk_en_aio_mclk",
+	[24] = "clk_en_hdmirx",
+	[25] = "clk_en_sata_1",
+	[26] = "clk_en_sata_alive_1",
+	[27] = "clk_en_ur2",
+	[28] = "clk_en_ur1",
+	[29] = "clk_en_fan",
+	[30] = "clk_en_dcphy_0",
+	[31] = "clk_en_dcphy_1",
+};
+
+static struct clk *clks[16 + 2 * 32] = {};
+
+static struct clk_onecell_data rtd_clks = {
+	.clks = clks,
+	.clk_num = ARRAY_SIZE(clks),
+};
+
+static void __init rtd1295_clk_init(struct device_node *node)
+{
+	void __iomem *base;
+	struct clk *osc;
+	int i;
+	static const char *clk_sys_parents[2] = { "pll_bus", "pll_bus_div2" };
+	static const char *clk_ve_parents[4] = { "clk_sysh", "pll_ve1", "pll_ve2", "pll_ve2" };
+
+	base = of_iomap(node, 0);
+
+	osc = of_clk_get(node, 0);
+
+	clks[RTD1295_CLK_PLL_SCPU] = rtd_scpu(base + 0x500, "pll_scpu", osc);
+	clks[RTD1295_CLK_PLL_BUS] = rtd_nf_ssc(base + 0x520, "pll_bus", osc);
+	clks[RTD1295_CLK_PLL_BUS_DIV2] = clk_register_fixed_factor(NULL, "pll_bus_div2", "pll_bus", 0, 1, 2);
+	clks[RTD1295_CLK_SYS] = clk_register_mux(NULL, "clk_sys", clk_sys_parents, 2, 0, base + 0x30, 0, 1, CLK_MUX_READ_ONLY, NULL);
+	clks[RTD1295_CLK_PLL_BUS_H] = rtd_nf_ssc(base + 0x540, "pll_bus_h", osc);
+	clks[RTD1295_CLK_SYSH] = clk_register_fixed_factor(NULL, "clk_sysh", "pll_bus_h", 0, 1, 1);
+	clks[RTD1295_CLK_PLL_DDSA] = rtd_nf_ssc(base + 0x560, "pll_ddsa", osc);
+	clks[RTD1295_CLK_PLL_DDSB] = rtd_nf_ssc(base + 0x580, "pll_ddsb", osc);
+	clks[RTD1295_CLK_PLL_VODMA] = rtd_mno_ctrl(base + 0x260, "pll_vodma", osc);
+	clk_register_fixed_factor(NULL, "clk_vodma", "pll_vodma", 0, 1, 1);
+	clks[RTD1295_CLK_EN_VO] = clk_register_gate(NULL, "clk_en_vo", "clk_vodma", CLK_IGNORE_UNUSED, base + 0xc, 15, 0, NULL);
+	clks[RTD1295_CLK_PLL_VE1] = rtd_mno_ctrl(base + 0x114, "pll_ve1", osc);
+	clks[RTD1295_CLK_PLL_VE2] = rtd_mno_ctrl(base + 0x1d0, "pll_ve2", osc);
+	clk_register_mux(NULL, "clk_ve1", clk_ve_parents, 4, 0, base + 0x4c, 0, 2, CLK_MUX_READ_ONLY, NULL);
+	clks[RTD1295_CLK_EN_VE1] = clk_register_gate(NULL, "clk_en_ve1", "clk_ve1", CLK_IGNORE_UNUSED, base + 0xc, 12, 0, NULL);
+	clk_register_mux(NULL, "clk_ve2", clk_ve_parents, 4, 0, base + 0x4c, 2, 2, CLK_MUX_READ_ONLY, NULL);
+	clks[RTD1295_CLK_EN_VE2] = clk_register_gate(NULL, "clk_en_ve2", "clk_ve2", CLK_IGNORE_UNUSED, base + 0xc, 13, 0, NULL);
+	clk_register_mux(NULL, "clk_ve3", clk_ve_parents, 4, 0, base + 0x4c, 4, 2, CLK_MUX_READ_ONLY, NULL);
+	clks[RTD1295_CLK_EN_VE3] = clk_register_gate(NULL, "clk_en_ve3", "clk_ve3", CLK_IGNORE_UNUSED, base + 0xc, 29, 0, NULL);
+	clks[RTD1295_CLK_PLL_GPU] = rtd_nf_ssc(base + 0x5a0, "pll_gpu", osc);
+	clk_register_fixed_factor(NULL, "clk_gpu", "pll_gpu", 0, 1, 1);
+	clks[RTD1295_CLK_EN_GPU] = clk_register_gate(NULL, "clk_en_gpu", "clk_gpu", CLK_IGNORE_UNUSED, base + 0xc, 11, 0, NULL);
+	clks[RTD1295_CLK_PLL_ACPU] = rtd_nf_ssc(base + 0x5c0, "pll_acpu", osc);
+
+	for (i = 0; i < ARRAY_SIZE(rtd1295_gates1); i++) {
+		if (!rtd1295_gates1[i])
+			continue;
+		clks[RTD1295_CLK_EN_BASE + i] = clk_register_gate(NULL, rtd1295_gates1[i], NULL, CLK_IGNORE_UNUSED, base + 0xc, i, 0, NULL);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(rtd1295_gates2); i++) {
+		if (!rtd1295_gates2[i])
+			continue;
+		clks[RTD1295_CLK_EN_BASE2 + i] = clk_register_gate(NULL, rtd1295_gates2[i], __clk_get_name(osc), CLK_IGNORE_UNUSED, base + 0x10, i, 0, NULL);
+	}
+
+	clk_put(osc);
+
+	of_clk_add_provider(node, of_clk_src_onecell_get, &rtd_clks);
+}
+CLK_OF_DECLARE(rtd1295, "realtek,rtd1295-clk", rtd1295_clk_init);
+
+static const char * const rtd1295_iso_gates[13] = {
+	/* "*unused", */
+	/* "*rvd", */
+	[ 2] = "clk_en_misc_cec0",
+	[ 3] = "clk_en_cbusrx_sys",
+	[ 4] = "clk_en_cbustx_sys",
+	[ 5] = "clk_en_cbus_sys",
+	[ 6] = "clk_en_cbus_osc",
+	[ 7] = "clk_en_misc_ir",
+	[ 8] = "clk_en_misc_ur0",
+	[ 9] = "clk_en_i2c0",
+	[10] = "clk_en_i2c1",
+	[11] = "clk_en_etn_250m",
+	[12] = "clk_en_etn_sys",
+};
+
+static struct clk *iso_clks[13] = {};
+
+static struct clk_onecell_data rtd_iso_clks = {
+	.clks = iso_clks,
+	.clk_num = ARRAY_SIZE(iso_clks),
+};
+
+static void __init rtd1295_iso_clk_init(struct device_node *node)
+{
+	void __iomem *base;
+	struct clk *osc;
+	int i;
+
+	base = of_iomap(node, 0);
+
+	osc = of_clk_get(node, 0);
+
+	for (i = 0; i < ARRAY_SIZE(rtd1295_iso_gates); i++) {
+		if (!rtd1295_iso_gates[i])
+			continue;
+		iso_clks[i] = clk_register_gate(NULL, rtd1295_iso_gates[i], __clk_get_name(osc), CLK_IGNORE_UNUSED, base + 0x8c, i, 0, NULL);
+	}
+
+	clk_put(osc);
+
+	of_clk_add_provider(node, of_clk_src_onecell_get, &rtd_iso_clks);
+}
+CLK_OF_DECLARE(rtd1295_iso, "realtek,rtd1295-iso-clk", rtd1295_iso_clk_init);
-- 
2.12.3