[PATCHv4 11/15] clk: ti: clockdomain: add clock provider support to clockdomains

Tero Kristo t-kristo at ti.com
Tue Oct 18 08:46:04 PDT 2016


Clockdomains can now be used as clock providers in the system. This
patch initializes the provider data during init, and parses the clocks
while they are being registered. An xlate function for the provider
is also given.

Signed-off-by: Tero Kristo <t-kristo at ti.com>
---
 .../devicetree/bindings/arm/omap/prcm.txt          |  13 ++
 .../devicetree/bindings/clock/ti/clockdomain.txt   |  12 +-
 arch/arm/mach-omap2/io.c                           |   2 +
 drivers/clk/ti/clock.h                             |   1 +
 drivers/clk/ti/clockdomain.c                       | 147 +++++++++++++++++++++
 include/linux/clk/ti.h                             |   3 +
 6 files changed, 177 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/omap/prcm.txt b/Documentation/devicetree/bindings/arm/omap/prcm.txt
index 3eb6d7a..301f576 100644
--- a/Documentation/devicetree/bindings/arm/omap/prcm.txt
+++ b/Documentation/devicetree/bindings/arm/omap/prcm.txt
@@ -47,6 +47,19 @@ cm: cm at 48004000 {
 	};
 }
 
+cm2: cm2 at 8000 {
+	compatible = "ti,omap4-cm2";
+	reg = <0x8000 0x3000>;
+	#address-cells = <1>;
+	#size-cells = <1>;
+	ranges = <0 0x8000 0x3000>;
+
+	l4_per_clkdm: l4_per_clkdm {
+		compatible = "ti,clockdomain";
+		reg = <0x1400 0x200>;
+	};
+};
+
 &cm_clocks {
 	omap2_32k_fck: omap_32k_fck {
 		#clock-cells = <0>;
diff --git a/Documentation/devicetree/bindings/clock/ti/clockdomain.txt b/Documentation/devicetree/bindings/clock/ti/clockdomain.txt
index cb76b3f..5d8ca61 100644
--- a/Documentation/devicetree/bindings/clock/ti/clockdomain.txt
+++ b/Documentation/devicetree/bindings/clock/ti/clockdomain.txt
@@ -14,11 +14,21 @@ hardware hierarchy.
 
 Required properties:
 - compatible : shall be "ti,clockdomain"
-- #clock-cells : from common clock binding; shall be set to 0.
+- #clock-cells : from common clock binding; shall be set to 1 if this
+		 clockdomain acts as a clock provider.
+
+Optional properties:
 - clocks : link phandles of clocks within this domain
+- reg : address for the clockdomain
 
 Examples:
 	dss_clkdm: dss_clkdm {
 		compatible = "ti,clockdomain";
 		clocks = <&dss1_alwon_fck_3430es2>, <&dss_ick_3430es2>;
 	};
+
+	l4_per_clkdm: l4_per_clkdm {
+		compatible = "ti,clockdomain";
+		#clock-cells = <1>;
+		reg = <0x1400 0x200>;
+	};
diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
index 0e9acdd..c1a5cfb 100644
--- a/arch/arm/mach-omap2/io.c
+++ b/arch/arm/mach-omap2/io.c
@@ -794,6 +794,8 @@ int __init omap_clk_init(void)
 		if (ret)
 			return ret;
 
+		ti_dt_clockdomains_early_setup();
+
 		of_clk_init(NULL);
 
 		ti_dt_clk_init_retry_clks();
diff --git a/drivers/clk/ti/clock.h b/drivers/clk/ti/clock.h
index 9b8a5f2..f6383ab 100644
--- a/drivers/clk/ti/clock.h
+++ b/drivers/clk/ti/clock.h
@@ -205,6 +205,7 @@ struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw,
 
 int ti_clk_get_memmap_index(struct device_node *node);
 void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index);
+void __iomem *ti_clk_get_reg_addr_clkdm(const char *clkdm_name, u16 offset);
 void ti_dt_clocks_register(struct ti_dt_clk *oclks);
 int ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
 		      ti_of_clk_init_cb_t func);
diff --git a/drivers/clk/ti/clockdomain.c b/drivers/clk/ti/clockdomain.c
index 704157d..7b0a6c3 100644
--- a/drivers/clk/ti/clockdomain.c
+++ b/drivers/clk/ti/clockdomain.c
@@ -28,6 +28,23 @@
 #define pr_fmt(fmt) "%s: " fmt, __func__
 
 /**
+ * struct ti_clkdm - TI clockdomain data structure
+ * @name: name of the clockdomain
+ * @index: index of the clk_iomap struct for this clkdm
+ * @offset: clockdomain offset from the beginning of the iomap
+ * @link: link to the list
+ */
+struct ti_clkdm {
+	const char *name;
+	int index;
+	u32 offset;
+	struct list_head link;
+	struct list_head clocks;
+};
+
+static LIST_HEAD(clkdms);
+
+/**
  * omap2_clkops_enable_clkdm - increment usecount on clkdm of @hw
  * @hw: struct clk_hw * of the clock being enabled
  *
@@ -116,6 +133,8 @@ void omap2_init_clk_clkdm(struct clk_hw *hw)
 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 	struct clockdomain *clkdm;
 	const char *clk_name;
+	struct ti_clkdm *ti_clkdm;
+	bool match = false;
 
 	if (!clk->clkdm_name)
 		return;
@@ -130,7 +149,21 @@ void omap2_init_clk_clkdm(struct clk_hw *hw)
 	} else {
 		pr_debug("clock: could not associate clk %s to clkdm %s\n",
 			 clk_name, clk->clkdm_name);
+		return;
 	}
+
+	list_for_each_entry(ti_clkdm, &clkdms, link) {
+		if (!strcmp(ti_clkdm->name, clk->clkdm_name)) {
+			match = true;
+			break;
+		}
+	}
+
+	if (!match)
+		return;
+
+	/* Add clock to the list of provided clocks */
+	list_add(&clk->clkdm_link, &ti_clkdm->clocks);
 }
 
 static void __init of_ti_clockdomain_setup(struct device_node *node)
@@ -161,11 +194,125 @@ static void __init of_ti_clockdomain_setup(struct device_node *node)
 	}
 }
 
+static struct clk_hw *clkdm_clk_xlate(struct of_phandle_args *clkspec,
+				      void *data)
+{
+	struct ti_clkdm *clkdm = data;
+	struct clk_hw_omap *clk;
+	u16 offset = clkspec->args[0];
+
+	list_for_each_entry(clk, &clkdm->clocks, clkdm_link)
+		if (((u32)clk->enable_reg & 0xffff) - clkdm->offset == offset)
+			return &clk->hw;
+
+	return ERR_PTR(-EINVAL);
+}
+
+static int ti_clk_register_clkdm(struct device_node *node)
+{
+	u64 clkdm_addr;
+	u64 inst_addr;
+	const __be32 *reg;
+	u32 offset;
+	int idx;
+	struct ti_clkdm *clkdm;
+	int ret;
+
+	reg = of_get_address(node, 0, NULL, NULL);
+	if (!reg)
+		return -ENOENT;
+
+	clkdm_addr = of_translate_address(node, reg);
+
+	reg = of_get_address(node->parent, 0, NULL, NULL);
+	if (!reg)
+		return -EINVAL;
+
+	inst_addr = of_translate_address(node->parent, reg);
+
+	offset = clkdm_addr - inst_addr;
+
+	idx = ti_clk_get_memmap_index(node->parent);
+
+	if (idx < 0) {
+		pr_err("bad memmap index for %s\n", node->name);
+		return idx;
+	}
+
+	clkdm = kzalloc(sizeof(*clkdm), GFP_KERNEL);
+	if (!clkdm)
+		return -ENOMEM;
+
+	clkdm->name = node->name;
+	clkdm->index = idx;
+	clkdm->offset = offset;
+
+	INIT_LIST_HEAD(&clkdm->clocks);
+
+	list_add(&clkdm->link, &clkdms);
+
+	ret = of_clk_add_hw_provider(node, clkdm_clk_xlate, clkdm);
+	if (ret) {
+		list_del(&clkdm->link);
+		kfree(clkdm);
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * ti_clk_get_reg_addr_clkdm - get register address relative to clockdomain
+ * @clkdm_name: parent clockdomain
+ * @offset: offset from the clockdomain
+ *
+ * Gets a register address relative to parent clockdomain. Searches the
+ * list of available clockdomain, and if match is found, calculates the
+ * register address from the iomap relative to the clockdomain.
+ * Returns the register address, or NULL if not found.
+ */
+void __iomem *ti_clk_get_reg_addr_clkdm(const char *clkdm_name, u16 offset)
+{
+	u32 reg;
+	struct clk_omap_reg *reg_setup;
+	struct ti_clkdm *clkdm;
+	bool match = false;
+
+	reg_setup = (struct clk_omap_reg *)®
+
+	/* XXX: get offset from clkdm, get base for instance */
+	list_for_each_entry(clkdm, &clkdms, link) {
+		if (!strcmp(clkdm->name, clkdm_name)) {
+			match = true;
+			break;
+		}
+	}
+
+	if (!match) {
+		pr_err("%s: no entry for %s\n", __func__, clkdm_name);
+		return NULL;
+	}
+
+	reg_setup->offset = clkdm->offset + offset;
+	reg_setup->index = clkdm->index;
+
+	return (void __iomem *)reg;
+}
+
 static const struct of_device_id ti_clkdm_match_table[] __initconst = {
 	{ .compatible = "ti,clockdomain" },
 	{ }
 };
 
+void __init ti_dt_clockdomains_early_setup(void)
+{
+	struct device_node *np;
+
+	for_each_matching_node(np, ti_clkdm_match_table) {
+		ti_clk_register_clkdm(np);
+	}
+}
+
 /**
  * ti_dt_clockdomains_setup - setup device tree clockdomains
  *
diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h
index 626ae94..afccb48 100644
--- a/include/linux/clk/ti.h
+++ b/include/linux/clk/ti.h
@@ -125,6 +125,7 @@ struct clk_hw_omap_ops {
 /**
  * struct clk_hw_omap - OMAP struct clk
  * @node: list_head connecting this clock into the full clock list
+ * @clkdm_link: list_head connecting this clock into the clockdomain
  * @enable_reg: register to write to enable the clock (see @enable_bit)
  * @enable_bit: bitshift to write to enable/disable the clock (see @enable_reg)
  * @flags: see "struct clk.flags possibilities" above
@@ -137,6 +138,7 @@ struct clk_hw_omap_ops {
 struct clk_hw_omap {
 	struct clk_hw		hw;
 	struct list_head	node;
+	struct list_head	clkdm_link;
 	unsigned long		fixed_rate;
 	u8			fixed_div;
 	void __iomem		*enable_reg;
@@ -251,6 +253,7 @@ int omap2_reprogram_dpllcore(struct clk_hw *clk, unsigned long rate,
 unsigned long omap2_get_dpll_rate(struct clk_hw_omap *clk);
 
 void ti_dt_clk_init_retry_clks(void);
+void ti_dt_clockdomains_early_setup(void);
 void ti_dt_clockdomains_setup(void);
 int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops);
 
-- 
1.9.1




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