[PATCH 3/3] clk: shmobile: Add R8A7790 clocks support

Laurent Pinchart laurent.pinchart+renesas at ideasonboard.com
Tue Oct 29 10:55:11 EDT 2013


The R8A7790 has several clocks that are too custom to be supported in a
generic driver. Those clocks can be divided in two categories:

- Fixed rate clocks with multiplier and divisor set according to boot
  mode configuration

- Custom divider clocks with SoC-specific divider values

This driver supports both.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
---
 .../bindings/clock/renesas,r8a7790-cpg-clocks.txt  |  26 +++
 drivers/clk/shmobile/Makefile                      |   1 +
 drivers/clk/shmobile/clk-r8a7790.c                 | 176 +++++++++++++++++++++
 include/dt-bindings/clock/r8a7790-clock.h          |  10 ++
 include/linux/clk/shmobile.h                       |  19 +++
 5 files changed, 232 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/renesas,r8a7790-cpg-clocks.txt
 create mode 100644 drivers/clk/shmobile/clk-r8a7790.c
 create mode 100644 include/linux/clk/shmobile.h

diff --git a/Documentation/devicetree/bindings/clock/renesas,r8a7790-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,r8a7790-cpg-clocks.txt
new file mode 100644
index 0000000..d889917
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/renesas,r8a7790-cpg-clocks.txt
@@ -0,0 +1,26 @@
+* Renesas R8A7790 Clock Pulse Generator (CPG)
+
+The CPG generates core clocks for the R8A7790. It includes three PLLs and
+several fixed ratio dividers.
+
+Required Properties:
+
+  - compatible: Must be "renesas,r8a7790-cpg-clocks"
+  - reg: Base address and length of the memory resource used by the CPG
+  - clocks: Reference to the parent clock
+  - #clock-cells: Must be 1
+  - clock-output-names: The name of the clocks, must be "main", "pll1",
+    "pll3", "lb", "qspi", "sdh", "sd0", "sd1".
+
+
+Example
+-------
+
+	cpg_clocks: cpg_clocks {
+		compatible = "renesas,r8a7790-cpg-clocks";
+		reg = <0 0xe6150000 0 0x1000>;
+		clocks = <&extal_clk>;
+		#clock-cells = <1>;
+		clock-output-names = "main", "pll1", "pll3", "lb",
+				     "qspi", "sdh", "sd0", "sd1";
+	};
diff --git a/drivers/clk/shmobile/Makefile b/drivers/clk/shmobile/Makefile
index 3275c78..949f29e 100644
--- a/drivers/clk/shmobile/Makefile
+++ b/drivers/clk/shmobile/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_ARCH_EMEV2)		+= clk-emev2.o
+obj-$(CONFIG_ARCH_R8A7790)		+= clk-r8a7790.o
 obj-$(CONFIG_ARCH_SHMOBILE_MULTI)	+= clk-div6.o
 obj-$(CONFIG_ARCH_SHMOBILE_MULTI)	+= clk-mstp.o
 
diff --git a/drivers/clk/shmobile/clk-r8a7790.c b/drivers/clk/shmobile/clk-r8a7790.c
new file mode 100644
index 0000000..2e76638
--- /dev/null
+++ b/drivers/clk/shmobile/clk-r8a7790.c
@@ -0,0 +1,176 @@
+/*
+ * r8a7790 Core CPG Clocks
+ *
+ * Copyright (C) 2013  Ideas On Board SPRL
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/shmobile.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/spinlock.h>
+
+#include <dt-bindings/clock/r8a7790-clock.h>
+
+#define CPG_NUM_CLOCKS			(R8A7790_CLK_SD1 + 1)
+
+struct r8a7790_cpg {
+	struct clk_onecell_data data;
+	spinlock_t lock;
+	void __iomem *reg;
+};
+
+/*
+ *   MD		EXTAL		PLL0	PLL1	PLL3
+ * 14 13 19	(MHz)		*1	*1
+ *---------------------------------------------------
+ * 0  0  0	15 x 1		x172/2	x208/2	x106
+ * 0  0  1	15 x 1		x172/2	x208/2	x88
+ * 0  1  0	20 x 1		x130/2	x156/2	x80
+ * 0  1  1	20 x 1		x130/2	x156/2	x66
+ * 1  0  0	26 / 2		x200/2	x240/2	x122
+ * 1  0  1	26 / 2		x200/2	x240/2	x102
+ * 1  1  0	30 / 2		x172/2	x208/2	x106
+ * 1  1  1	30 / 2		x172/2	x208/2	x88
+ *
+ * *1 :	Table 7.6 indicates VCO ouput (PLLx = VCO/2)
+ */
+#define CPG_PLL_CONFIG_INDEX(md)	((((md) & BIT(14)) >> 12) | \
+					 (((md) & BIT(13)) >> 12) | \
+					 (((md) & BIT(19)) >> 19))
+struct cpg_pll_config {
+	unsigned int extal_div;
+	unsigned int pll1_mult;
+	unsigned int pll3_mult;
+};
+
+static const struct cpg_pll_config cpg_pll_configs[8] = {
+	{ 1, 208, 106 }, { 1, 208,  88 }, { 1, 156,  80 }, { 1, 156,  66 },
+	{ 2, 240, 122 }, { 2, 240, 102 }, { 2, 208, 106 }, { 2, 208,  88 },
+};
+
+/* SDHI divisors */
+static const struct clk_div_table cpg_sdh_div_table[] = {
+	{  0,  2 }, {  1,  3 }, {  2,  4 }, {  3,  6 },
+	{  4,  8 }, {  5, 12 }, {  6, 16 }, {  7, 18 },
+	{  8, 24 }, { 10, 36 }, { 11, 48 }, {  0,  0 },
+};
+
+static const struct clk_div_table cpg_sd01_div_table[] = {
+	{  5, 12 }, {  6, 16 }, {  7, 18 }, {  8, 24 },
+	{ 10, 36 }, { 11, 48 }, { 12, 10 }, {  0,  0 },
+};
+
+static u32 cpg_mode __initdata;
+
+#define CPG_SDCKCR			0x00000074
+
+static void __init r8a7790_cpg_clocks_init(struct device_node *np)
+{
+	const struct cpg_pll_config *config;
+	struct r8a7790_cpg *cpg;
+	struct clk **clks;
+	unsigned int i;
+
+	cpg = kzalloc(sizeof(*cpg), GFP_KERNEL);
+	clks = kzalloc(CPG_NUM_CLOCKS * sizeof(*clks), GFP_KERNEL);
+	if (cpg == NULL || clks == NULL) {
+		kfree(clks);
+		kfree(cpg);
+		pr_err("%s: failed to allocate cpg\n", __func__);
+		return;
+	}
+
+	spin_lock_init(&cpg->lock);
+
+	cpg->data.clks = clks;
+	cpg->data.clk_num = CPG_NUM_CLOCKS;
+
+	cpg->reg = of_iomap(np, 0);
+	if (WARN_ON(cpg->reg == NULL)) {
+		kfree(cpg->data.clks);
+		kfree(cpg);
+		return;
+	}
+
+	config = &cpg_pll_configs[CPG_PLL_CONFIG_INDEX(cpg_mode)];
+
+	for (i = 0; i < CPG_NUM_CLOCKS; ++i) {
+		const struct clk_div_table *table = NULL;
+		const char *parent_name = "main";
+		const char *name;
+		unsigned int shift;
+		unsigned int mult = 1;
+		unsigned int div = 1;
+		struct clk *clk;
+
+		of_property_read_string_index(np, "clock-output-names", i,
+					      &name);
+
+		switch (i) {
+		case R8A7790_CLK_MAIN:
+			parent_name = of_clk_get_parent_name(np, 0);
+			div = config->extal_div;
+			break;
+		case R8A7790_CLK_PLL1:
+			mult = config->pll1_mult / 2;
+			break;
+		case R8A7790_CLK_PLL3:
+			mult = config->pll3_mult;
+			break;
+		case R8A7790_CLK_LB:
+			div = cpg_mode & BIT(18) ? 36 : 24;
+			break;
+		case R8A7790_CLK_QSPI:
+			div = (cpg_mode & (BIT(3) | BIT(2) | BIT(1))) == BIT(2)
+			    ? 16 : 20;
+			break;
+		case R8A7790_CLK_SDH:
+			table = cpg_sdh_div_table;
+			shift = 8;
+			break;
+		case R8A7790_CLK_SD0:
+			table = cpg_sd01_div_table;
+			shift = 4;
+			break;
+		case R8A7790_CLK_SD1:
+			table = cpg_sd01_div_table;
+			shift = 0;
+			break;
+		}
+
+		if (!table)
+			clk = clk_register_fixed_factor(NULL, name, parent_name,
+							0, mult, div);
+		else
+			clk = clk_register_divider_table(NULL, name,
+							 parent_name, 0,
+							 cpg->reg + CPG_SDCKCR,
+							 shift, 4, 0, table,
+							 &cpg->lock);
+
+		if (IS_ERR(clk))
+			pr_err("%s: failed to register %s %s clock (%ld)\n",
+			       __func__, np->name, name, PTR_ERR(clk));
+	}
+
+	of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
+}
+CLK_OF_DECLARE(r8a7790_cpg_clks, "renesas,r8a7790-cpg-clocks",
+	       r8a7790_cpg_clocks_init);
+
+void __init r8a7790_clocks_init(u32 mode)
+{
+	cpg_mode = mode;
+
+	of_clk_init(NULL);
+}
diff --git a/include/dt-bindings/clock/r8a7790-clock.h b/include/dt-bindings/clock/r8a7790-clock.h
index 19f2b48..f0ed742 100644
--- a/include/dt-bindings/clock/r8a7790-clock.h
+++ b/include/dt-bindings/clock/r8a7790-clock.h
@@ -10,6 +10,16 @@
 #ifndef __DT_BINDINGS_CLOCK_R8A7790_H__
 #define __DT_BINDINGS_CLOCK_R8A7790_H__
 
+/* CPG */
+#define R8A7790_CLK_MAIN		0
+#define R8A7790_CLK_PLL1		1
+#define R8A7790_CLK_PLL3		2
+#define R8A7790_CLK_LB			3
+#define R8A7790_CLK_QSPI		4
+#define R8A7790_CLK_SDH			5
+#define R8A7790_CLK_SD0			6
+#define R8A7790_CLK_SD1			7
+
 /* MSTP1 */
 #define R8A7790_CLK_CMT0		20
 
diff --git a/include/linux/clk/shmobile.h b/include/linux/clk/shmobile.h
new file mode 100644
index 0000000..b090855
--- /dev/null
+++ b/include/linux/clk/shmobile.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2013 Ideas On Board SPRL
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_CLK_SHMOBILE_H_
+#define __LINUX_CLK_SHMOBILE_H_
+
+#include <linux/types.h>
+
+void r8a7790_clocks_init(u32 mode);
+
+#endif
-- 
1.8.1.5




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