[RFC 2/4] clk: Add Ingenic X1000 CGU driver

[PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>]

Add support for the clocks provided by CGU in Ingenic X1000 SoC.

Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
---
 drivers/clk/ingenic/Makefile    |   1 +
 drivers/clk/ingenic/x1000-cgu.c | 203 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 204 insertions(+)
 create mode 100644 drivers/clk/ingenic/x1000-cgu.c

diff --git a/drivers/clk/ingenic/Makefile b/drivers/clk/ingenic/Makefile
index cd47b06..89c665b 100644
--- a/drivers/clk/ingenic/Makefile
+++ b/drivers/clk/ingenic/Makefile
@@ -1,3 +1,4 @@
 obj-y				+= cgu.o
 obj-$(CONFIG_MACH_JZ4740)	+= jz4740-cgu.o
 obj-$(CONFIG_MACH_JZ4780)	+= jz4780-cgu.o
+obj-$(CONFIG_MACH_X1000)	+= x1000-cgu.o
diff --git a/drivers/clk/ingenic/x1000-cgu.c b/drivers/clk/ingenic/x1000-cgu.c
new file mode 100644
index 0000000..a228688
--- /dev/null
+++ b/drivers/clk/ingenic/x1000-cgu.c
@@ -0,0 +1,203 @@
+/*
+ * Ingenic X1000 SoC CGU driver
+ *
+ * Copyright (c) 2016 PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <dt-bindings/clock/x1000-cgu.h>
+#include "cgu.h"
+
+/* CGU register offsets */
+#define CGU_REG_CLOCKCONTROL	0x00
+#define CGU_REG_APLL		0x10
+#define CGU_REG_MPLL		0x14
+
+/* CLKGR0, OPCR are not defined in X1000, JZ4780 PM so assuming them to be correct */
+#define CGU_REG_CLKGR0		0x20
+#define CGU_REG_OPCR		0x24
+#define CGU_REG_CLKGR1		0x28
+#define CGU_REG_DDRCDR		0x2c
+
+/* bits within the OPCR register */
+#define OPCR_SPENDN0		(1 << 7)
+#define OPCR_SPENDN1		(1 << 6)
+
+static struct ingenic_cgu *cgu;
+
+static const s8 pll_od_encoding[16] = {
+	0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
+	0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf,
+};
+
+static const struct ingenic_cgu_clk_info x1000_cgu_clocks[] = {
+
+	/* External clocks */
+
+	[X1000_CLK_EXCLK] = { "ext", CGU_CLK_EXT },
+	[X1000_CLK_RTCLK] = { "rtc", CGU_CLK_EXT },
+
+	/* PLLs */
+
+#define DEF_PLL(name) { \
+	.reg = CGU_REG_ ## name, \
+	.m_shift = 19, \
+	.m_bits = 13, \
+	.m_offset = 1, \
+	.n_shift = 13, \
+	.n_bits = 6, \
+	.n_offset = 1, \
+	.od_shift = 9, \
+	.od_bits = 4, \
+	.od_max = 16, \
+	.od_encoding = pll_od_encoding, \
+	.stable_bit = 6, \
+	.bypass_bit = 1, \
+	.enable_bit = 0, \
+}
+
+	[X1000_CLK_APLL] = {
+		"apll", CGU_CLK_PLL,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.pll = DEF_PLL(APLL),
+	},
+
+	[X1000_CLK_MPLL] = {
+		"mpll", CGU_CLK_PLL,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.pll = DEF_PLL(MPLL),
+	},
+
+#undef DEF_PLL
+
+	/* Muxes & dividers */
+
+	[X1000_CLK_SCLKA] = {
+		"sclk_a", CGU_CLK_MUX,
+		.parents = { -1, X1000_CLK_APLL, X1000_CLK_EXCLK,
+			     X1000_CLK_RTCLK },
+		.mux = { CGU_REG_CLOCKCONTROL, 30, 2 },
+	},
+
+	[X1000_CLK_CPUMUX] = {
+		"cpumux", CGU_CLK_MUX,
+		.parents = { -1, X1000_CLK_SCLKA, X1000_CLK_MPLL,
+			     -1 },
+		.mux = { CGU_REG_CLOCKCONTROL, 28, 2 },
+	},
+
+	[X1000_CLK_CPU] = {
+		"cpu", CGU_CLK_DIV,
+		.parents = { X1000_CLK_CPUMUX, -1, -1, -1 },
+		.div = { CGU_REG_CLOCKCONTROL, 0, 1, 4, 22, -1, -1 },
+	},
+
+	[X1000_CLK_L2CACHE] = {
+		"l2cache", CGU_CLK_DIV,
+		.parents = { X1000_CLK_CPUMUX, -1, -1, -1 },
+		.div = { CGU_REG_CLOCKCONTROL, 4, 1, 4, -1, -1, -1 },
+	},
+
+	[X1000_CLK_AHB0] = {
+		"ahb0", CGU_CLK_MUX | CGU_CLK_DIV,
+		.parents = { -1, X1000_CLK_SCLKA, X1000_CLK_MPLL,
+			     -1 },
+		.mux = { CGU_REG_CLOCKCONTROL, 26, 2 },
+		.div = { CGU_REG_CLOCKCONTROL, 8, 1, 4, 21, -1, -1 },
+	},
+
+	[X1000_CLK_AHB2PMUX] = {
+		"ahb2_apb_mux", CGU_CLK_MUX,
+		.parents = { -1, X1000_CLK_SCLKA, X1000_CLK_MPLL,
+			     X1000_CLK_RTCLK },
+		.mux = { CGU_REG_CLOCKCONTROL, 24, 2 },
+	},
+
+	[X1000_CLK_AHB2] = {
+		"ahb2", CGU_CLK_DIV,
+		.parents = { X1000_CLK_AHB2PMUX, -1, -1, -1 },
+		.div = { CGU_REG_CLOCKCONTROL, 12, 1, 4, 20, -1, -1 },
+	},
+
+	[X1000_CLK_PCLK] = {
+		"pclk", CGU_CLK_DIV,
+		.parents = { X1000_CLK_AHB2PMUX, -1, -1, -1 },
+		.div = { CGU_REG_CLOCKCONTROL, 16, 1, 4, 20, -1, -1 },
+	},
+
+	[X1000_CLK_DDR] = {
+		"ddr", CGU_CLK_MUX | CGU_CLK_DIV,
+		.parents = { -1, X1000_CLK_SCLKA, X1000_CLK_MPLL, -1 },
+		.mux = { CGU_REG_DDRCDR, 30, 2 },
+		.div = { CGU_REG_DDRCDR, 0, 1, 4, 29, 28, 27 },
+	},
+
+	/* Gate-only clocks */
+
+	[X1000_CLK_UART0] = {
+		"uart0", CGU_CLK_GATE,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 15 },
+	},
+
+	[X1000_CLK_UART1] = {
+		"uart1", CGU_CLK_GATE,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 16 },
+	},
+
+	[X1000_CLK_UART2] = {
+		"uart2", CGU_CLK_GATE,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 17 },
+	},
+
+	[X1000_CLK_PDMA] = {
+		"pdma", CGU_CLK_GATE,
+		.parents = { X1000_CLK_EXCLK, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 21 },
+	},
+
+	[X1000_CLK_DDR0] = {
+		"ddr0", CGU_CLK_GATE,
+		.parents = { X1000_CLK_DDR, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 30 },
+	},
+
+	[X1000_CLK_DDR1] = {
+		"ddr1", CGU_CLK_GATE,
+		.parents = { X1000_CLK_DDR, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR0, 31 },
+	},
+
+	[X1000_CLK_CORE1] = {
+		"core1", CGU_CLK_GATE,
+		.parents = { X1000_CLK_CPU, -1, -1, -1 },
+		.gate = { CGU_REG_CLKGR1, 15 },
+	},
+};
+
+static void __init x1000_cgu_init(struct device_node *np)
+{
+	int retval;
+
+	cgu = ingenic_cgu_new(x1000_cgu_clocks,
+			      ARRAY_SIZE(x1000_cgu_clocks), np);
+	if (!cgu) {
+		pr_err("%s: failed to initialise CGU\n", __func__);
+		return;
+	}
+
+	retval = ingenic_cgu_register_clocks(cgu);
+	if (retval) {
+		pr_err("%s: failed to register CGU Clocks\n", __func__);
+		return;
+	}
+}
+CLK_OF_DECLARE(x1000_cgu, "ingenic,x1000-cgu", x1000_cgu_init);
-- 
2.10.0