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Subject[PATCH 1/2] clk: meson: Add vid_pll divider driver
Date
Add support the VID_PLL fully programmable divider used right after the
HDMI PLL clock source. It is used to achieve complex fractional division
with a programmble bitfield.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
drivers/clk/meson/Makefile | 2 +-
drivers/clk/meson/clkc.h | 6 +++
drivers/clk/meson/vid-pll-div.c | 90 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 97 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/meson/vid-pll-div.c

diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index 72ec8c4..0234767 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -2,7 +2,7 @@
# Makefile for Meson specific clk
#

-obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-phase.o
+obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-phase.o vid-pll-div.o
obj-$(CONFIG_COMMON_CLK_AMLOGIC_AUDIO) += clk-triphase.o sclk-div.o
obj-$(CONFIG_COMMON_CLK_MESON_AO) += meson-aoclk.o
obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o
diff --git a/drivers/clk/meson/clkc.h b/drivers/clk/meson/clkc.h
index 6b96d55..9166605 100644
--- a/drivers/clk/meson/clkc.h
+++ b/drivers/clk/meson/clkc.h
@@ -90,6 +90,11 @@ struct meson_clk_phase_data {
int meson_clk_degrees_from_val(unsigned int val, unsigned int width);
unsigned int meson_clk_degrees_to_val(int degrees, unsigned int width);

+struct meson_vid_pll_div_data {
+ struct parm val;
+ struct parm sel;
+};
+
#define MESON_GATE(_name, _reg, _bit) \
struct clk_regmap _name = { \
.data = &(struct clk_regmap_gate_data){ \
@@ -112,5 +117,6 @@ extern const struct clk_ops meson_clk_cpu_ops;
extern const struct clk_ops meson_clk_mpll_ro_ops;
extern const struct clk_ops meson_clk_mpll_ops;
extern const struct clk_ops meson_clk_phase_ops;
+extern const struct clk_ops meson_vid_pll_div_ro_ops;

#endif /* __CLKC_H */
diff --git a/drivers/clk/meson/vid-pll-div.c b/drivers/clk/meson/vid-pll-div.c
new file mode 100644
index 0000000..5f267be
--- /dev/null
+++ b/drivers/clk/meson/vid-pll-div.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 BayLibre, SAS.
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+
+#include <linux/clk-provider.h>
+#include "clkc.h"
+
+static inline struct meson_vid_pll_div_data *
+meson_vid_pll_div_data(struct clk_regmap *clk)
+{
+ return (struct meson_vid_pll_div_data *)clk->data;
+}
+
+/*
+ * This vid_pll divided is a fully programmable fractionnal divider to
+ * achieve complex video clock rates.
+ *
+ * Here are provided the commonly used fraction values provided by Amlogic.
+ */
+
+struct vid_pll_div {
+ unsigned int shift_val;
+ unsigned int shift_sel;
+ unsigned int frac_top;
+ unsigned int frac_bot;
+};
+
+#define VID_PLL_DIV(_val, _sel, _ft, _fb) \
+ { \
+ .shift_val = (_val), \
+ .shift_sel = (_sel), \
+ .frac_top = (_ft), \
+ .frac_bot = (_fb), \
+ }
+
+static const struct vid_pll_div vid_pll_div_table[] = {
+ VID_PLL_DIV(0x0aaa, 0, 2, 1), /* 2/1 => /2 */
+ VID_PLL_DIV(0x5294, 2, 5, 2), /* 5/2 => /2.5 */
+ VID_PLL_DIV(0x0db6, 0, 3, 1), /* 3/1 => /3 */
+ VID_PLL_DIV(0x36cc, 1, 7, 2), /* 7/2 => /3.5 */
+ VID_PLL_DIV(0x6666, 2, 15, 4), /* 15/4 => /3.75 */
+ VID_PLL_DIV(0x0ccc, 4, 4, 1), /* 4/1 => /4 */
+ VID_PLL_DIV(0x739c, 2, 5, 1), /* 5/1 => /5 */
+ VID_PLL_DIV(0x0e38, 0, 6, 1), /* 6/1 => /6 */
+ VID_PLL_DIV(0x0000, 3, 25, 4), /* 25/4 => /6.25 */
+ VID_PLL_DIV(0x3c78, 1, 7, 1), /* 7/1 => /7 */
+ VID_PLL_DIV(0x78f0, 2, 15, 2), /* 15/2 => /7.5 */
+ VID_PLL_DIV(0x0fc0, 0, 12, 1), /* 12/1 => /12 */
+ VID_PLL_DIV(0x3f80, 1, 14, 1), /* 14/1 => /14 */
+ VID_PLL_DIV(0x7f80, 2, 15, 1), /* 15/1 => /15 */
+};
+
+#define to_meson_vid_pll_div(_hw) container_of(_hw, struct meson_vid_pll_div, hw)
+
+const struct vid_pll_div *_get_table_val(unsigned int shift_val,
+ unsigned int shift_sel)
+{
+ int i;
+
+ for (i = 0 ; i < ARRAY_SIZE(vid_pll_div_table) ; ++i) {
+ if (vid_pll_div_table[i].shift_val == shift_val &&
+ vid_pll_div_table[i].shift_sel == shift_sel)
+ return &vid_pll_div_table[i];
+ }
+
+ return NULL;
+}
+
+static unsigned long meson_vid_pll_div_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_vid_pll_div_data *pll_div = meson_vid_pll_div_data(clk);
+ const struct vid_pll_div *div;
+
+ div = _get_table_val(meson_parm_read(clk->map, &pll_div->val),
+ meson_parm_read(clk->map, &pll_div->sel));
+ if (!div || !div->frac_top) {
+ pr_info("%s: Invalid config value for vid_pll_div\n", __func__);
+ return parent_rate;
+ }
+
+ return DIV_ROUND_UP_ULL(parent_rate * div->frac_bot, div->frac_top);
+}
+
+const struct clk_ops meson_vid_pll_div_ro_ops = {
+ .recalc_rate = meson_vid_pll_div_recalc_rate,
+};
--
2.7.4
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