[PATCH RFC 1/2] clk: sunxi: Add sun8i display support

Jean-Francois Moine moinejf at free.fr
Tue Jan 5 10:28:25 PST 2016


Add the clock types which are used by the sun8i family for video.

Signed-off-by: Jean-Francois Moine <moinejf at free.fr>
---
 drivers/clk/sunxi/Makefile            |   1 +
 drivers/clk/sunxi/clk-sun8i-display.c | 247 ++++++++++++++++++++++++++++++++++
 2 files changed, 258 insertions(+)
 create mode 100644 drivers/clk/sunxi/clk-sun8i-display.c

diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
index cb4c299..145c078 100644
--- a/drivers/clk/sunxi/Makefile
+++ b/drivers/clk/sunxi/Makefile
@@ -10,6 +10,7 @@ obj-y += clk-a10-pll2.o
 obj-y += clk-a20-gmac.o
 obj-y += clk-mod0.o
 obj-y += clk-simple-gates.o
+obj-y += clk-sun8i-display.o
 obj-y += clk-sun8i-mbus.o
 obj-y += clk-sun9i-core.o
 obj-y += clk-sun9i-mmc.o
diff --git a/drivers/clk/sunxi/clk-sun8i-display.c b/drivers/clk/sunxi/clk-sun8i-display.c
new file mode 100644
index 0000000..eded572
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun8i-display.c
@@ -0,0 +1,247 @@
+/*
+ * Copyright 2015 Jean-Francois Moine <moinejf at free.fr>
+ *
+ * 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.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/rational.h>
+#include <linux/delay.h>
+
+static DEFINE_SPINLOCK(sun8i_display_lock);
+
+/* PLL3 (video) and PLL10 (de) */
+struct clk_fact {
+	struct clk_hw hw;
+	void __iomem *reg;
+};
+#define to_clk_fact(_hw) container_of(_hw, struct clk_fact, hw)
+
+#define SUN8I_PLL3_MSHIFT	0
+#define SUN8I_PLL3_MMASK	0x0f
+#define SUN8I_PLL3_NSHIFT	8
+#define SUN8I_PLL3_NMASK	0x7f
+#define SUN8I_PLL3_MODE_SEL	0x01000000
+#define SUN8I_PLL3_FRAC_CLK	0x02000000
+
+static int sun8i_pll3_get_fact(unsigned long rate,
+			unsigned long parent_rate,
+			unsigned long *n, unsigned long *m)
+{
+	if (rate == 297000000)
+		return 1;
+	if (rate == 270000000)
+		return 0;
+	rational_best_approximation(rate, parent_rate,
+				SUN8I_PLL3_NMASK + 1, SUN8I_PLL3_MMASK + 1,
+				n, m);
+	return -1;
+}
+
+static unsigned long sun8i_pll3_recalc_rate(struct clk_hw *hw,
+					unsigned long parent_rate)
+{
+	struct clk_fact *fact = to_clk_fact(hw);
+	u32 reg;
+	u32 n, m;
+
+	reg = readl(fact->reg);
+	if (reg & SUN8I_PLL3_MODE_SEL) {
+		n = (reg >> SUN8I_PLL3_NSHIFT) & SUN8I_PLL3_NMASK;
+		m = (reg >> SUN8I_PLL3_MSHIFT) & SUN8I_PLL3_MMASK;
+		return parent_rate / (m + 1) * (n + 1);
+	}
+	if (reg & SUN8I_PLL3_FRAC_CLK)
+		return 297000000;
+	return 270000000;
+}
+
+static long sun8i_pll3_round_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long *parent_rate)
+{
+	int frac;
+	unsigned long n, m;
+
+	frac = sun8i_pll3_get_fact(rate, *parent_rate, &n, &m);
+	if (frac == 1)
+		return 297000000;
+	if (frac == 0)
+		return 270000000;
+	return (*parent_rate * n) / m;
+}
+
+static int sun8i_pll3_set_rate(struct clk_hw *hw, unsigned long rate,
+			unsigned long parent_rate)
+{
+	struct clk_fact *fact = to_clk_fact(hw);
+	u32 reg;
+	int frac;
+	unsigned long n, m;
+
+	reg = readl(fact->reg) &
+			~(SUN8I_PLL3_MODE_SEL |
+			  SUN8I_PLL3_FRAC_CLK |
+			  (SUN8I_PLL3_NMASK << SUN8I_PLL3_NSHIFT) |
+			  (SUN8I_PLL3_MMASK << SUN8I_PLL3_MSHIFT));
+
+	frac = sun8i_pll3_get_fact(rate, parent_rate, &n, &m);
+	if (frac == 1)
+		reg |= SUN8I_PLL3_FRAC_CLK;	/* 297MHz */
+	else if (frac == 0)
+		;				/* 270MHz */
+	else
+		reg |= SUN8I_PLL3_MODE_SEL |
+			((n - 1) << SUN8I_PLL3_NSHIFT) |
+			((m - 1) << SUN8I_PLL3_MSHIFT);
+
+	writel(reg, fact->reg);
+
+	/* delay 500us so pll stabilizes */
+	__delay(500);
+
+	return 0;
+}
+
+static const struct clk_ops clk_sun8i_pll3_fact_ops = {
+	.recalc_rate = sun8i_pll3_recalc_rate,
+	.round_rate = sun8i_pll3_round_rate,
+	.set_rate = sun8i_pll3_set_rate,
+};
+
+static void __init sun8i_pll3_setup(struct device_node *node)
+{
+	const char *clk_name = node->name, *parent;
+	struct clk_fact *fact;
+	struct clk_gate *gate;
+	void __iomem *reg;
+	struct clk *clk;
+
+	of_property_read_string(node, "clock-output-names", &clk_name);
+	parent = of_clk_get_parent_name(node, 0);
+
+	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+	if (IS_ERR(reg)) {
+		pr_err("%s: Could not map the clock registers\n", clk_name);
+		return;
+	}
+
+	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+	if (!gate)
+		return;
+
+	gate->reg = reg;
+	gate->bit_idx = 31;
+	gate->lock = &sun8i_display_lock;
+
+	fact = kzalloc(sizeof(*fact), GFP_KERNEL);
+	if (!fact)
+		goto free_gate;
+
+	fact->reg = reg;
+
+	clk = clk_register_composite(NULL, clk_name,
+				     &parent, 1,
+				     NULL, NULL,
+				     &fact->hw, &clk_sun8i_pll3_fact_ops,
+				     &gate->hw, &clk_gate_ops,
+				     0);
+	if (IS_ERR(clk)) {
+		pr_err("%s: Couldn't register the clock\n", clk_name);
+		goto free_fact;
+	}
+
+	of_clk_add_provider(node, of_clk_src_simple_get, clk);
+
+	return;
+
+free_fact:
+	kfree(fact);
+free_gate:
+	kfree(gate);
+}
+
+CLK_OF_DECLARE(sun8i_pll3, "allwinner,sun8i-pll3-clk", sun8i_pll3_setup);
+
+/* DE, TCON0, TVE, HDMI, DEINTERLACE  */
+static void __init sun8i_display_setup(struct device_node *node)
+{
+	const char *clk_name = node->name;
+	const char *parents[2];
+	struct clk_mux *mux = NULL;
+	struct clk_divider *div;
+	struct clk_gate *gate;
+	void __iomem *reg;
+	struct clk *clk;
+	int n;
+
+	of_property_read_string(node, "clock-output-names", &clk_name);
+
+	reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+	if (IS_ERR(reg)) {
+		pr_err("%s: Could not map the clock registers\n", clk_name);
+		return;
+	}
+
+	n = of_clk_parent_fill(node, parents, ARRAY_SIZE(parents));
+
+	if (n > 1) {				/* many possible sources */
+		mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+		if (!mux)
+			return;
+		mux->reg = reg;
+		mux->shift = 24;
+		mux->mask = 0x07;
+		mux->lock = &sun8i_display_lock;
+	}
+
+	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+	if (!gate)
+		goto free_gate;
+
+	gate->reg = reg;
+	gate->bit_idx = 31;
+	gate->lock = &sun8i_display_lock;
+
+	div = kzalloc(sizeof(*div), GFP_KERNEL);
+	if (!div)
+		goto free_gate;
+
+	div->reg = reg;
+	div->shift = 0;
+	div->width = 4;
+	div->lock = &sun8i_display_lock;
+
+	clk = clk_register_composite(NULL, clk_name,
+				     parents, n,
+				     mux ? &mux->hw : NULL, &clk_mux_ops,
+				     &div->hw, &clk_divider_ops,
+				     &gate->hw, &clk_gate_ops,
+				     0);
+	if (IS_ERR(clk)) {
+		pr_err("%s: Couldn't register the clock\n", clk_name);
+		goto free_div;
+	}
+
+	of_clk_add_provider(node, of_clk_src_simple_get, clk);
+
+	return;
+
+free_div:
+	kfree(div);
+free_gate:
+	kfree(gate);
+	kfree(mux);
+}
+
+CLK_OF_DECLARE(sun8i_display, "allwinner,sun8i-display-clk", sun8i_display_setup);
-- 
2.6.4




More information about the linux-arm-kernel mailing list