clk: exynos: Add Exynos850 clock driver

Heavily influenced by its Linux kernel counterpart. It's implemented on
top of recently added Samsung CCF clock framework API. For now only UART
leaf clocks are implemented, along with all preceding clocks in CMU_TOP
and CMU_PERI. The UART baud clock is required in the serial driver, to
get its rate for the consequent baud rate calculation.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/drivers/clk/exynos/clk-exynos850.c b/drivers/clk/exynos/clk-exynos850.c
new file mode 100644
index 0000000..cf94a3e
--- /dev/null
+++ b/drivers/clk/exynos/clk-exynos850.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Samsung Exynos850 clock driver.
+ * Copyright (c) 2023 Linaro Ltd.
+ * Author: Sam Protsenko <semen.protsenko@linaro.org>
+ */
+
+#include <dm.h>
+#include <asm/io.h>
+#include <dt-bindings/clock/exynos850.h>
+#include "clk.h"
+
+/* ---- CMU_TOP ------------------------------------------------------------- */
+
+/* Register Offset definitions for CMU_TOP (0x120e0000) */
+#define PLL_CON0_PLL_MMC			0x0100
+#define PLL_CON3_PLL_MMC			0x010c
+#define PLL_CON0_PLL_SHARED0			0x0140
+#define PLL_CON3_PLL_SHARED0			0x014c
+#define PLL_CON0_PLL_SHARED1			0x0180
+#define PLL_CON3_PLL_SHARED1			0x018c
+#define CLK_CON_MUX_MUX_CLKCMU_PERI_BUS		0x1070
+#define CLK_CON_MUX_MUX_CLKCMU_PERI_IP		0x1074
+#define CLK_CON_MUX_MUX_CLKCMU_PERI_UART	0x1078
+#define CLK_CON_DIV_CLKCMU_PERI_BUS		0x187c
+#define CLK_CON_DIV_CLKCMU_PERI_IP		0x1880
+#define CLK_CON_DIV_CLKCMU_PERI_UART		0x1884
+#define CLK_CON_DIV_PLL_SHARED0_DIV2		0x188c
+#define CLK_CON_DIV_PLL_SHARED0_DIV3		0x1890
+#define CLK_CON_DIV_PLL_SHARED0_DIV4		0x1894
+#define CLK_CON_DIV_PLL_SHARED1_DIV2		0x1898
+#define CLK_CON_DIV_PLL_SHARED1_DIV3		0x189c
+#define CLK_CON_DIV_PLL_SHARED1_DIV4		0x18a0
+#define CLK_CON_GAT_GATE_CLKCMU_PERI_BUS	0x2080
+#define CLK_CON_GAT_GATE_CLKCMU_PERI_IP		0x2084
+#define CLK_CON_GAT_GATE_CLKCMU_PERI_UART	0x2088
+
+static const struct samsung_pll_clock top_pure_pll_clks[] = {
+	PLL(pll_0822x, CLK_FOUT_SHARED0_PLL, "fout_shared0_pll", "clock-oscclk",
+	    PLL_CON3_PLL_SHARED0),
+	PLL(pll_0822x, CLK_FOUT_SHARED1_PLL, "fout_shared1_pll", "clock-oscclk",
+	    PLL_CON3_PLL_SHARED1),
+	PLL(pll_0831x, CLK_FOUT_MMC_PLL, "fout_mmc_pll", "clock-oscclk",
+	    PLL_CON3_PLL_MMC),
+};
+
+/* List of parent clocks for Muxes in CMU_TOP */
+PNAME(mout_shared0_pll_p)	= { "clock-oscclk", "fout_shared0_pll" };
+PNAME(mout_shared1_pll_p)	= { "clock-oscclk", "fout_shared1_pll" };
+PNAME(mout_mmc_pll_p)		= { "clock-oscclk", "fout_mmc_pll" };
+/* List of parent clocks for Muxes in CMU_TOP: for CMU_PERI */
+PNAME(mout_peri_bus_p)		= { "dout_shared0_div4", "dout_shared1_div4" };
+PNAME(mout_peri_uart_p)		= { "clock-oscclk", "dout_shared0_div4",
+				    "dout_shared1_div4", "clock-oscclk" };
+PNAME(mout_peri_ip_p)		= { "clock-oscclk", "dout_shared0_div4",
+				    "dout_shared1_div4", "clock-oscclk" };
+
+static const struct samsung_mux_clock top_pure_mux_clks[] = {
+	MUX(CLK_MOUT_SHARED0_PLL, "mout_shared0_pll", mout_shared0_pll_p,
+	    PLL_CON0_PLL_SHARED0, 4, 1),
+	MUX(CLK_MOUT_SHARED1_PLL, "mout_shared1_pll", mout_shared1_pll_p,
+	    PLL_CON0_PLL_SHARED1, 4, 1),
+	MUX(CLK_MOUT_MMC_PLL, "mout_mmc_pll", mout_mmc_pll_p,
+	    PLL_CON0_PLL_MMC, 4, 1),
+};
+
+static const struct samsung_mux_clock top_peri_mux_clks[] = {
+	MUX(CLK_MOUT_PERI_BUS, "mout_peri_bus", mout_peri_bus_p,
+	    CLK_CON_MUX_MUX_CLKCMU_PERI_BUS, 0, 1),
+	MUX(CLK_MOUT_PERI_UART, "mout_peri_uart", mout_peri_uart_p,
+	    CLK_CON_MUX_MUX_CLKCMU_PERI_UART, 0, 2),
+	MUX(CLK_MOUT_PERI_IP, "mout_peri_ip", mout_peri_ip_p,
+	    CLK_CON_MUX_MUX_CLKCMU_PERI_IP, 0, 2),
+};
+
+static const struct samsung_div_clock top_pure_div_clks[] = {
+	DIV(CLK_DOUT_SHARED0_DIV3, "dout_shared0_div3", "mout_shared0_pll",
+	    CLK_CON_DIV_PLL_SHARED0_DIV3, 0, 2),
+	DIV(CLK_DOUT_SHARED0_DIV2, "dout_shared0_div2", "mout_shared0_pll",
+	    CLK_CON_DIV_PLL_SHARED0_DIV2, 0, 1),
+	DIV(CLK_DOUT_SHARED1_DIV3, "dout_shared1_div3", "mout_shared1_pll",
+	    CLK_CON_DIV_PLL_SHARED1_DIV3, 0, 2),
+	DIV(CLK_DOUT_SHARED1_DIV2, "dout_shared1_div2", "mout_shared1_pll",
+	    CLK_CON_DIV_PLL_SHARED1_DIV2, 0, 1),
+	DIV(CLK_DOUT_SHARED0_DIV4, "dout_shared0_div4", "dout_shared0_div2",
+	    CLK_CON_DIV_PLL_SHARED0_DIV4, 0, 1),
+	DIV(CLK_DOUT_SHARED1_DIV4, "dout_shared1_div4", "dout_shared1_div2",
+	    CLK_CON_DIV_PLL_SHARED1_DIV4, 0, 1),
+};
+
+static const struct samsung_div_clock top_peri_div_clks[] = {
+	DIV(CLK_DOUT_PERI_BUS, "dout_peri_bus", "gout_peri_bus",
+	    CLK_CON_DIV_CLKCMU_PERI_BUS, 0, 4),
+	DIV(CLK_DOUT_PERI_UART, "dout_peri_uart", "gout_peri_uart",
+	    CLK_CON_DIV_CLKCMU_PERI_UART, 0, 4),
+	DIV(CLK_DOUT_PERI_IP, "dout_peri_ip", "gout_peri_ip",
+	    CLK_CON_DIV_CLKCMU_PERI_IP, 0, 4),
+};
+
+static const struct samsung_gate_clock top_peri_gate_clks[] = {
+	GATE(CLK_GOUT_PERI_BUS, "gout_peri_bus", "mout_peri_bus",
+	     CLK_CON_GAT_GATE_CLKCMU_PERI_BUS, 21, 0, 0),
+	GATE(CLK_GOUT_PERI_UART, "gout_peri_uart", "mout_peri_uart",
+	     CLK_CON_GAT_GATE_CLKCMU_PERI_UART, 21, 0, 0),
+	GATE(CLK_GOUT_PERI_IP, "gout_peri_ip", "mout_peri_ip",
+	     CLK_CON_GAT_GATE_CLKCMU_PERI_IP, 21, 0, 0),
+};
+
+static const struct samsung_clk_group top_cmu_clks[] = {
+	/* CMU_TOP_PURECLKCOMP */
+	{ S_CLK_PLL, top_pure_pll_clks, ARRAY_SIZE(top_pure_pll_clks) },
+	{ S_CLK_MUX, top_pure_mux_clks, ARRAY_SIZE(top_pure_mux_clks) },
+	{ S_CLK_DIV, top_pure_div_clks, ARRAY_SIZE(top_pure_div_clks) },
+
+	/* CMU_TOP clocks for CMU_PERI */
+	{ S_CLK_MUX, top_peri_mux_clks, ARRAY_SIZE(top_peri_mux_clks) },
+	{ S_CLK_GATE, top_peri_gate_clks, ARRAY_SIZE(top_peri_gate_clks) },
+	{ S_CLK_DIV, top_peri_div_clks, ARRAY_SIZE(top_peri_div_clks) },
+};
+
+static int exynos850_cmu_top_probe(struct udevice *dev)
+{
+	return samsung_cmu_register_one(dev, top_cmu_clks,
+					ARRAY_SIZE(top_cmu_clks));
+}
+
+static const struct udevice_id exynos850_cmu_top_ids[] = {
+	{ .compatible = "samsung,exynos850-cmu-top" },
+	{ }
+};
+
+U_BOOT_DRIVER(exynos850_cmu_top) = {
+	.name		= "exynos850-cmu-top",
+	.id		= UCLASS_CLK,
+	.of_match	= exynos850_cmu_top_ids,
+	.ops		= &ccf_clk_ops,
+	.probe		= exynos850_cmu_top_probe,
+	.flags		= DM_FLAG_PRE_RELOC,
+};
+
+/* ---- CMU_PERI ------------------------------------------------------------ */
+
+/* Register Offset definitions for CMU_PERI (0x10030000) */
+#define PLL_CON0_MUX_CLKCMU_PERI_BUS_USER	0x0600
+#define PLL_CON0_MUX_CLKCMU_PERI_UART_USER	0x0630
+#define CLK_CON_GAT_GOUT_PERI_UART_IPCLK	0x20a8
+#define CLK_CON_GAT_GOUT_PERI_UART_PCLK		0x20ac
+
+/* List of parent clocks for Muxes in CMU_PERI */
+PNAME(mout_peri_bus_user_p)	= { "clock-oscclk", "dout_peri_bus" };
+PNAME(mout_peri_uart_user_p)	= { "clock-oscclk", "dout_peri_uart" };
+
+static const struct samsung_mux_clock peri_mux_clks[] = {
+	MUX(CLK_MOUT_PERI_BUS_USER, "mout_peri_bus_user", mout_peri_bus_user_p,
+	    PLL_CON0_MUX_CLKCMU_PERI_BUS_USER, 4, 1),
+	MUX(CLK_MOUT_PERI_UART_USER, "mout_peri_uart_user",
+	    mout_peri_uart_user_p, PLL_CON0_MUX_CLKCMU_PERI_UART_USER, 4, 1),
+};
+
+static const struct samsung_gate_clock peri_gate_clks[] = {
+	GATE(CLK_GOUT_UART_IPCLK, "gout_uart_ipclk", "mout_peri_uart_user",
+	     CLK_CON_GAT_GOUT_PERI_UART_IPCLK, 21, 0, 0),
+	GATE(CLK_GOUT_UART_PCLK, "gout_uart_pclk", "mout_peri_bus_user",
+	     CLK_CON_GAT_GOUT_PERI_UART_PCLK, 21, 0, 0),
+};
+
+static const struct samsung_clk_group peri_cmu_clks[] = {
+	{ S_CLK_MUX, peri_mux_clks, ARRAY_SIZE(peri_mux_clks) },
+	{ S_CLK_GATE, peri_gate_clks, ARRAY_SIZE(peri_gate_clks) },
+};
+
+static int exynos850_cmu_peri_probe(struct udevice *dev)
+{
+	return samsung_register_cmu(dev, peri_cmu_clks, exynos850_cmu_top);
+}
+
+static const struct udevice_id exynos850_cmu_peri_ids[] = {
+	{ .compatible = "samsung,exynos850-cmu-peri" },
+	{ }
+};
+
+U_BOOT_DRIVER(exynos850_cmu_peri) = {
+	.name		= "exynos850-cmu-peri",
+	.id		= UCLASS_CLK,
+	.of_match	= exynos850_cmu_peri_ids,
+	.ops		= &ccf_clk_ops,
+	.probe		= exynos850_cmu_peri_probe,
+	.flags		= DM_FLAG_PRE_RELOC,
+};