[PATCH 1/5] clk: berlin: add support for clocks

From: Alexandre Belloni
Date: Wed Apr 23 2014 - 10:01:38 EST


Add support for clocks having their own register set.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
drivers/clk/berlin/Makefile | 2 +-
drivers/clk/berlin/clk.c | 132 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 133 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/berlin/clk.c

diff --git a/drivers/clk/berlin/Makefile b/drivers/clk/berlin/Makefile
index 94859513de90..9bfa58eaf25a 100644
--- a/drivers/clk/berlin/Makefile
+++ b/drivers/clk/berlin/Makefile
@@ -1,4 +1,4 @@
-obj-y += pll.o
+obj-y += pll.o clk.o
obj-$(CONFIG_MACH_BERLIN_BG2) += pll-berlin2.o
obj-$(CONFIG_MACH_BERLIN_BG2CD) += pll-berlin2.o
obj-$(CONFIG_MACH_BERLIN_BG2Q) += pll-berlin2q.o
diff --git a/drivers/clk/berlin/clk.c b/drivers/clk/berlin/clk.c
new file mode 100644
index 000000000000..a0e688e5bead
--- /dev/null
+++ b/drivers/clk/berlin/clk.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2014 Marvell Technology Group Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/bitops.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+#include "common.h"
+
+#define CLKEN (1 << 0)
+#define CLKPLLSEL_MASK 7
+#define CLKPLLSEL_SHIFT 1
+#define CLKPLLSWITCH (1 << 4)
+#define CLKSWITCH (1 << 5)
+#define CLKD3SWITCH (1 << 6)
+#define CLKSEL_MASK 7
+#define CLKSEL_SHIFT 7
+
+struct berlin_clk {
+ struct clk_hw hw;
+ void __iomem *base;
+};
+
+#define to_berlin_clk(hw) container_of(hw, struct berlin_clk, hw)
+
+static u8 clk_div[] = {1, 2, 4, 6, 8, 12, 1, 1};
+
+static unsigned long berlin_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 val, divider;
+ struct berlin_clk *clk = to_berlin_clk(hw);
+
+ val = readl_relaxed(clk->base);
+ if (val & CLKD3SWITCH)
+ divider = 3;
+ else {
+ if (val & CLKSWITCH) {
+ val >>= CLKSEL_SHIFT;
+ val &= CLKSEL_MASK;
+ divider = clk_div[val];
+ } else
+ divider = 1;
+ }
+
+ return parent_rate / divider;
+}
+
+static u8 berlin_clk_get_parent(struct clk_hw *hw)
+{
+ u32 val;
+ struct berlin_clk *clk = to_berlin_clk(hw);
+
+ val = readl_relaxed(clk->base);
+ if (val & CLKPLLSWITCH) {
+ val >>= CLKPLLSEL_SHIFT;
+ val &= CLKPLLSEL_MASK;
+ return val;
+ }
+
+ return 0;
+}
+
+static const struct clk_ops berlin_clk_ops = {
+ .recalc_rate = berlin_clk_recalc_rate,
+ .get_parent = berlin_clk_get_parent,
+};
+
+static void __init berlin_clk_setup(struct device_node *np)
+{
+ struct clk_init_data init;
+ struct berlin_clk *bclk;
+ struct clk *clk;
+ const char **parent_names;
+ int nparents, i, ret;
+
+ bclk = kzalloc(sizeof(*bclk), GFP_KERNEL);
+ if (WARN_ON(!bclk))
+ return;
+
+ bclk->base = of_iomap(np, 0);
+ if (WARN_ON(!bclk->base))
+ goto exit;
+
+ nparents = of_clk_get_parent_count(np);
+ if (WARN_ON(!nparents))
+ goto exit;
+
+ parent_names = kzalloc((sizeof(char *) * nparents), GFP_KERNEL);
+ if (WARN_ON(!parent_names))
+ goto exit;
+
+ init.name = np->name;
+ init.ops = &berlin_clk_ops;
+ for (i = 0; i < nparents; i++) {
+ parent_names[i] = of_clk_get_parent_name(np, i);
+ if (!parent_names[i])
+ break;
+ }
+ init.parent_names = parent_names;
+ init.num_parents = i;
+
+ bclk->hw.init = &init;
+
+ clk = clk_register(NULL, &bclk->hw);
+ kfree(parent_names);
+ if (WARN_ON(IS_ERR(clk)))
+ goto exit;
+
+ ret = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ WARN_ON(ret);
+
+ return;
+exit:
+ kfree(bclk);
+}
+
+CLK_OF_DECLARE(berlin_clk, "marvell,berlin-clk", berlin_clk_setup);
--
1.9.1

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