[PATCH v2 1/6] clk: berlin: add common pll driver

Jisheng Zhang jszhang at marvell.com
Fri Nov 20 00:42:27 PST 2015


Add pll driver for Marvell SoCs newer than BG2, BG2CD, BG2Q.

Signed-off-by: Jisheng Zhang <jszhang at marvell.com>
---
 drivers/clk/berlin/Makefile |   1 +
 drivers/clk/berlin/pll.c    | 133 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 134 insertions(+)
 create mode 100644 drivers/clk/berlin/pll.c

diff --git a/drivers/clk/berlin/Makefile b/drivers/clk/berlin/Makefile
index 2a36ab7..eee42b0 100644
--- a/drivers/clk/berlin/Makefile
+++ b/drivers/clk/berlin/Makefile
@@ -1,4 +1,5 @@
 obj-y += berlin2-avpll.o berlin2-pll.o berlin2-div.o
+obj-y += pll.o
 obj-$(CONFIG_MACH_BERLIN_BG2)	+= bg2.o
 obj-$(CONFIG_MACH_BERLIN_BG2CD)	+= bg2.o
 obj-$(CONFIG_MACH_BERLIN_BG2Q)	+= bg2q.o
diff --git a/drivers/clk/berlin/pll.c b/drivers/clk/berlin/pll.c
new file mode 100644
index 0000000..435445e
--- /dev/null
+++ b/drivers/clk/berlin/pll.c
@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2015 Marvell Technology Group Ltd.
+ *
+ * Author: Jisheng Zhang <jszhang at marvell.com>
+ *
+ * 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/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+#define PLL_CTRL0	0x0
+#define PLL_CTRL1	0x4
+#define PLL_CTRL2	0x8
+#define PLL_CTRL3	0xC
+#define PLL_CTRL4	0x10
+#define PLL_STATUS	0x14
+
+#define PLL_SOURCE_MAX	2
+
+struct berlin_pll {
+	struct clk_hw	hw;
+	void __iomem	*ctrl;
+	void __iomem	*bypass;
+	u8		bypass_shift;
+};
+
+#define to_berlin_pll(hw)       container_of(hw, struct berlin_pll, hw)
+
+static unsigned long berlin_pll_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	u32 val, fbdiv, rfdiv, vcodivsel, bypass;
+	struct berlin_pll *pll = to_berlin_pll(hw);
+
+	bypass = readl_relaxed(pll->bypass);
+	if (bypass & (1 << pll->bypass_shift))
+		return parent_rate;
+
+	val = readl_relaxed(pll->ctrl + PLL_CTRL0);
+	fbdiv = (val >> 12) & 0x1FF;
+	rfdiv = (val >> 3) & 0x1FF;
+	val = readl_relaxed(pll->ctrl + PLL_CTRL1);
+	vcodivsel = (val >> 9) & 0x7;
+	return parent_rate * fbdiv * 4 / rfdiv /
+		(1 << vcodivsel);
+}
+
+static u8 berlin_pll_get_parent(struct clk_hw *hw)
+{
+	struct berlin_pll *pll = to_berlin_pll(hw);
+	u32 bypass = readl_relaxed(pll->bypass);
+
+	return !!(bypass & (1 << pll->bypass_shift));
+}
+
+static const struct clk_ops berlin_pll_ops = {
+	.recalc_rate	= berlin_pll_recalc_rate,
+	.get_parent	= berlin_pll_get_parent,
+};
+
+static void __init berlin_pll_setup(struct device_node *np)
+{
+	struct clk_init_data init;
+	struct berlin_pll *pll;
+	const char *parent_names[PLL_SOURCE_MAX];
+	struct clk *clk;
+	int ret, num_parents;
+	u8 bypass_shift;
+
+	num_parents = of_clk_get_parent_count(np);
+	if (num_parents <= 0 || num_parents > PLL_SOURCE_MAX)
+		return;
+
+	ret = of_property_read_u8(np, "bypass-shift", &bypass_shift);
+	if (ret)
+		return;
+
+	of_clk_parent_fill(np, parent_names, num_parents);
+
+	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return;
+
+	pll->ctrl = of_iomap(np, 0);
+	if (WARN_ON(!pll->ctrl))
+		goto err_iomap_ctrl;
+
+	pll->bypass = of_iomap(np, 1);
+	if (WARN_ON(!pll->bypass))
+		goto err_iomap_bypass;
+
+	init.name = np->name;
+	init.flags = 0;
+	init.ops = &berlin_pll_ops;
+	init.parent_names = parent_names;
+	init.num_parents = num_parents;
+
+	pll->hw.init = &init;
+	pll->bypass_shift = bypass_shift;
+
+	clk = clk_register(NULL, &pll->hw);
+	if (WARN_ON(IS_ERR(clk)))
+		goto err_clk_register;
+
+	ret = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+	if (WARN_ON(ret))
+		goto err_clk_add;
+	return;
+
+err_clk_add:
+	clk_unregister(clk);
+err_clk_register:
+	iounmap(pll->bypass);
+err_iomap_bypass:
+	iounmap(pll->ctrl);
+err_iomap_ctrl:
+	kfree(pll);
+}
+CLK_OF_DECLARE(berlin_pll, "marvell,berlin-pll", berlin_pll_setup);
-- 
2.6.2




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