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path: root/drivers/clk/socfpga/clk-periph.c
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Diffstat (limited to 'drivers/clk/socfpga/clk-periph.c')
-rw-r--r--drivers/clk/socfpga/clk-periph.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-periph.c b/drivers/clk/socfpga/clk-periph.c
new file mode 100644
index 000000000000..81623a3736f9
--- /dev/null
+++ b/drivers/clk/socfpga/clk-periph.c
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2011-2012 Calxeda, Inc.
+ * Copyright (C) 2012-2013 Altera Corporation <www.altera.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Based from clk-highbank.c
+ *
+ */
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include "clk.h"
+
+#define to_socfpga_periph_clk(p) container_of(p, struct socfpga_periph_clk, hw.hw)
+
+static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct socfpga_periph_clk *socfpgaclk = to_socfpga_periph_clk(hwclk);
+ u32 div;
+
+ if (socfpgaclk->fixed_div)
+ div = socfpgaclk->fixed_div;
+ else
+ div = ((readl(socfpgaclk->hw.reg) & 0x1ff) + 1);
+
+ return parent_rate / div;
+}
+
+static const struct clk_ops periclk_ops = {
+ .recalc_rate = clk_periclk_recalc_rate,
+};
+
+static __init void __socfpga_periph_init(struct device_node *node,
+ const struct clk_ops *ops)
+{
+ u32 reg;
+ struct clk *clk;
+ struct socfpga_periph_clk *periph_clk;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ struct clk_init_data init;
+ int rc;
+ u32 fixed_div;
+
+ of_property_read_u32(node, "reg", &reg);
+
+ periph_clk = kzalloc(sizeof(*periph_clk), GFP_KERNEL);
+ if (WARN_ON(!periph_clk))
+ return;
+
+ periph_clk->hw.reg = clk_mgr_base_addr + reg;
+
+ rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
+ if (rc)
+ periph_clk->fixed_div = 0;
+ else
+ periph_clk->fixed_div = fixed_div;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ init.flags = 0;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ periph_clk->hw.hw.init = &init;
+
+ clk = clk_register(NULL, &periph_clk->hw.hw);
+ if (WARN_ON(IS_ERR(clk))) {
+ kfree(periph_clk);
+ return;
+ }
+ rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+
+void __init socfpga_periph_init(struct device_node *node)
+{
+ __socfpga_periph_init(node, &periclk_ops);
+}