[PATCH v10 2/4] clk: meson: add emmc sub clock phase delay driver

From: Liang Yang
Date: Fri Jan 21 2022 - 02:46:36 EST


Export the emmc sub clock phase delay ops which will be used
by the emmc sub clock driver itself.

Signed-off-by: Liang Yang <liang.yang@xxxxxxxxxxx>
---
drivers/clk/meson/Kconfig | 4 ++
drivers/clk/meson/Makefile | 1 +
drivers/clk/meson/clk-phase-delay.c | 69 +++++++++++++++++++++++++++++
drivers/clk/meson/clk-phase-delay.h | 20 +++++++++
4 files changed, 94 insertions(+)
create mode 100644 drivers/clk/meson/clk-phase-delay.c
create mode 100644 drivers/clk/meson/clk-phase-delay.h

diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
index 3014e2f1fbb4..bb0f59eea366 100644
--- a/drivers/clk/meson/Kconfig
+++ b/drivers/clk/meson/Kconfig
@@ -18,6 +18,10 @@ config COMMON_CLK_MESON_PHASE
tristate
select COMMON_CLK_MESON_REGMAP

+config COMMON_CLK_MESON_PHASE_DELAY
+ tristate
+ select COMMON_CLK_MESON_REGMAP
+
config COMMON_CLK_MESON_PLL
tristate
select COMMON_CLK_MESON_REGMAP
diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index b3ef5f67820f..99fe4eeed000 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_COMMON_CLK_MESON_MPLL) += clk-mpll.o
obj-$(CONFIG_COMMON_CLK_MESON_PHASE) += clk-phase.o
obj-$(CONFIG_COMMON_CLK_MESON_PLL) += clk-pll.o
obj-$(CONFIG_COMMON_CLK_MESON_REGMAP) += clk-regmap.o
+obj-$(CONFIG_COMMON_CLK_MESON_PHASE_DELAY) += clk-phase-delay.o
obj-$(CONFIG_COMMON_CLK_MESON_SCLK_DIV) += sclk-div.o
obj-$(CONFIG_COMMON_CLK_MESON_VID_PLL_DIV) += vid-pll-div.o

diff --git a/drivers/clk/meson/clk-phase-delay.c b/drivers/clk/meson/clk-phase-delay.c
new file mode 100644
index 000000000000..3c1ae0ee2a24
--- /dev/null
+++ b/drivers/clk/meson/clk-phase-delay.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+
+#include "clk-regmap.h"
+#include "clk-phase-delay.h"
+
+static inline struct meson_clk_phase_delay_data *
+meson_clk_get_phase_delay_data(struct clk_regmap *clk)
+{
+ return clk->data;
+}
+
+static int meson_clk_phase_delay_get_phase(struct clk_hw *hw)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_clk_phase_delay_data *ph;
+ unsigned long period_ps, p, d;
+ int degrees;
+
+ ph = meson_clk_get_phase_delay_data(clk);
+ p = meson_parm_read(clk->map, &ph->phase);
+ degrees = p * 360 / (1 << (ph->phase.width));
+
+ period_ps = DIV_ROUND_UP_ULL(NSEC_PER_SEC * 1000ull,
+ clk_hw_get_rate(hw));
+
+ d = meson_parm_read(clk->map, &ph->delay);
+ degrees += d * ph->delay_step_ps * 360 / period_ps;
+ degrees %= 360;
+
+ return degrees;
+}
+
+static int meson_clk_phase_delay_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_clk_phase_delay_data *ph;
+ unsigned long period_ps, d = 0;
+ unsigned int p;
+
+ ph = meson_clk_get_phase_delay_data(clk);
+ period_ps = DIV_ROUND_UP_ULL(NSEC_PER_SEC * 1000ull,
+ clk_hw_get_rate(hw));
+
+ /*
+ * First compute the phase index (p), the remainder (r) is the
+ * part we'll try to acheive using the delays (d).
+ */
+ p = 360 / 1 << (ph->phase.width);
+ degrees = degrees / p;
+ d = DIV_ROUND_CLOSEST((degrees % p) * period_ps,
+ 360 * ph->delay_step_ps);
+ d = min(d, PMASK(ph->delay.width));
+
+ meson_parm_write(clk->map, &ph->phase, degrees);
+ meson_parm_write(clk->map, &ph->delay, d);
+ return 0;
+}
+
+const struct clk_ops meson_clk_phase_delay_ops = {
+ .get_phase = meson_clk_phase_delay_get_phase,
+ .set_phase = meson_clk_phase_delay_set_phase,
+};
+EXPORT_SYMBOL_GPL(meson_clk_phase_delay_ops);
diff --git a/drivers/clk/meson/clk-phase-delay.h b/drivers/clk/meson/clk-phase-delay.h
new file mode 100644
index 000000000000..b4f211d02c84
--- /dev/null
+++ b/drivers/clk/meson/clk-phase-delay.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+/*
+ * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
+ */
+
+#ifndef __MESON_CLK_PHASE_DELAY_H
+#define __MESON_CLK_PHASE_DELAY_H
+
+#include <linux/clk-provider.h>
+#include "parm.h"
+
+struct meson_clk_phase_delay_data {
+ struct parm phase;
+ struct parm delay;
+ unsigned int delay_step_ps;
+};
+
+extern const struct clk_ops meson_clk_phase_delay_ops;
+
+#endif /* __MESON_CLK_PHASE_DELAY_H */
--
2.34.1