[PATCHv10 03/41] CLK: ti: add init support for clock IP blocks

[Tero Kristo]

ti_dt_clk_init_provider() can now be used to initialize the contents of
a single clock IP block. This parses all the clocks under the IP block
and calls the corresponding init function for them.

This patch also introduces a helper function for the TI clock drivers
to get register info from DT and append the master IP info to this.

Signed-off-by: Tero Kristo <t-kristo at ti.com>
---
 drivers/clk/ti/clk.c   |   98 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/clk/ti.h |   14 +++++++
 2 files changed, 112 insertions(+)

diff --git a/drivers/clk/ti/clk.c b/drivers/clk/ti/clk.c
index ef1a7cd..63f85e9 100644
--- a/drivers/clk/ti/clk.c
+++ b/drivers/clk/ti/clk.c
@@ -19,10 +19,15 @@
 #include <linux/clkdev.h>
 #include <linux/clk/ti.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/list.h>
 
 #undef pr_fmt
 #define pr_fmt(fmt) "%s: " fmt, __func__
 
+extern struct of_device_id __clk_of_table[];
+static int ti_dt_clk_regmap_index;
+
 /**
  * ti_dt_clocks_register - register DT alias clocks during boot
  * @oclks: list of clocks to register
@@ -53,3 +58,96 @@ void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
 		}
 	}
 }
+
+typedef int (*ti_of_clk_init_cb_t)(struct device_node *);
+
+struct clk_init_item {
+	int index;
+	struct device_node *np;
+	ti_of_clk_init_cb_t init_cb;
+	struct list_head node;
+};
+
+static LIST_HEAD(retry_list);
+
+/**
+ * ti_clk_get_reg_addr - get register address for a clock register
+ * @node: device node for the clock
+ * @index: register index from the clock node
+ *
+ * Builds clock register address from device tree information. This
+ * is a struct of type clk_omap_reg.
+ */
+void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
+{
+	struct clk_omap_reg *reg;
+	u32 val;
+	u32 tmp;
+
+	reg = (struct clk_omap_reg *)&tmp;
+	reg->index = ti_dt_clk_regmap_index;
+
+	if (of_property_read_u32_index(node, "reg", index, &val)) {
+		pr_err("%s must have reg[%d]!\n", node->name, index);
+		return NULL;
+	}
+
+	reg->offset = val;
+
+	return (void __iomem *)tmp;
+}
+
+/**
+ * ti_dt_clk_init_provider - init master clock provider
+ * @parent: master node
+ * @index: internal index for clk_reg_ops
+ *
+ * Initializes a master clock IP block and its child clock nodes.
+ * Regmap is provided for accessing the register space for the
+ * IP block and all the clocks under it.
+ */
+void ti_dt_clk_init_provider(struct device_node *parent, int index)
+{
+	const struct of_device_id *match;
+	struct device_node *np;
+	ti_of_clk_init_cb_t clk_init_cb;
+	struct clk_init_item *retry;
+	struct clk_init_item *tmp;
+	int ret;
+
+	ti_dt_clk_regmap_index = index;
+
+	for_each_child_of_node(parent, np) {
+		match = of_match_node(__clk_of_table, np);
+		if (!match)
+			continue;
+		clk_init_cb = (ti_of_clk_init_cb_t)match->data;
+		pr_debug("%s: initializing: %s\n", __func__, np->name);
+		ret = clk_init_cb(np);
+		if (ret == -EAGAIN) {
+			pr_debug("%s: adding to again list...\n", np->name);
+			retry = kzalloc(sizeof(*retry), GFP_KERNEL);
+			retry->np = np;
+			retry->init_cb = clk_init_cb;
+			list_add(&retry->node, &retry_list);
+		} else if (ret) {
+			pr_err("%s: clock init failed for %s (%d)!\n", __func__,
+			       np->name, ret);
+		}
+	}
+
+	list_for_each_entry_safe(retry, tmp, &retry_list, node) {
+		pr_debug("%s: retry-init: %s\n", __func__, retry->np->name);
+		ti_dt_clk_regmap_index = retry->index;
+		ret = retry->init_cb(retry->np);
+		if (ret == -EAGAIN) {
+			pr_debug("%s failed again?\n", retry->np->name);
+		} else {
+			if (ret)
+				pr_err("%s: clock init failed for %s (%d)!\n",
+				       __func__, retry->np->name, ret);
+			list_del(&retry->node);
+			kfree(retry);
+		}
+	}
+}
diff --git a/include/linux/clk/ti.h b/include/linux/clk/ti.h
index df94c24..d6bf530 100644
--- a/include/linux/clk/ti.h
+++ b/include/linux/clk/ti.h
@@ -36,7 +36,21 @@ struct ti_dt_clk {
 		.node_name = name,	\
 	}
 
+/* Maximum number of clock regmaps */
+#define CLK_MAX_REGMAPS			4
 
+/**
+ * struct clk_omap_reg - OMAP register declaration
+ * @offset: offset from the master IP module base address
+ * @index: index of the master IP module
+ */
+struct clk_omap_reg {
+	u16 offset;
+	u16 index;
+};
+
+void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index);
 void ti_dt_clocks_register(struct ti_dt_clk *oclks);
+void ti_dt_clk_init_provider(struct device_node *np, int index);
 
 #endif
-- 
1.7.9.5