[PATCH v7 10/11] clk: actions: Add pll clock support
Manivannan Sadhasivam
manivannan.sadhasivam at linaro.org
Mon Mar 26 10:39:04 PDT 2018
Add support for Actions Semi PLL clock.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam at linaro.org>
---
drivers/clk/actions/Makefile | 1 +
drivers/clk/actions/owl-pll.c | 194 ++++++++++++++++++++++++++++++++++++++++++
drivers/clk/actions/owl-pll.h | 92 ++++++++++++++++++++
3 files changed, 287 insertions(+)
create mode 100644 drivers/clk/actions/owl-pll.c
create mode 100644 drivers/clk/actions/owl-pll.h
diff --git a/drivers/clk/actions/Makefile b/drivers/clk/actions/Makefile
index 53431aef6e9c..31b68eab9309 100644
--- a/drivers/clk/actions/Makefile
+++ b/drivers/clk/actions/Makefile
@@ -6,3 +6,4 @@ clk-owl-y += owl-mux.o
clk-owl-y += owl-divider.o
clk-owl-y += owl-factor.o
clk-owl-y += owl-composite.o
+clk-owl-y += owl-pll.o
diff --git a/drivers/clk/actions/owl-pll.c b/drivers/clk/actions/owl-pll.c
new file mode 100644
index 000000000000..058e06d7099f
--- /dev/null
+++ b/drivers/clk/actions/owl-pll.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// OWL pll clock driver
+//
+// Copyright (c) 2014 Actions Semi Inc.
+// Author: David Liu <liuwei at actions-semi.com>
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam at linaro.org>
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+
+#include "owl-pll.h"
+
+static u32 owl_pll_calculate_mul(struct owl_pll_hw *pll_hw, unsigned long rate)
+{
+ u32 mul;
+
+ mul = DIV_ROUND_CLOSEST(rate, pll_hw->bfreq);
+ if (mul < pll_hw->min_mul)
+ mul = pll_hw->min_mul;
+ else if (mul > pll_hw->max_mul)
+ mul = pll_hw->max_mul;
+
+ return mul &= mul_mask(pll_hw);
+}
+
+static unsigned long _get_table_rate(const struct clk_pll_table *table,
+ unsigned int val)
+{
+ const struct clk_pll_table *clkt;
+
+ for (clkt = table; clkt->rate; clkt++)
+ if (clkt->val == val)
+ return clkt->rate;
+
+ return 0;
+}
+
+static const struct clk_pll_table *_get_pll_table(
+ const struct clk_pll_table *table, unsigned long rate)
+{
+ const struct clk_pll_table *clkt;
+
+ for (clkt = table; clkt->rate; clkt++) {
+ if (clkt->rate == rate) {
+ table = clkt;
+ break;
+ } else if (clkt->rate < rate)
+ table = clkt;
+ }
+
+ return table;
+}
+
+static long owl_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ struct owl_pll_hw *pll_hw = &pll->pll_hw;
+ const struct clk_pll_table *clkt;
+ u32 mul;
+
+ if (pll_hw->table) {
+ clkt = _get_pll_table(pll_hw->table, rate);
+ return clkt->rate;
+ }
+
+ /* fixed frequency */
+ if (pll_hw->width == 0)
+ return pll_hw->bfreq;
+
+ mul = owl_pll_calculate_mul(pll_hw, rate);
+
+ return pll_hw->bfreq * mul;
+}
+
+static unsigned long owl_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ struct owl_pll_hw *pll_hw = &pll->pll_hw;
+ const struct owl_clk_common *common = &pll->common;
+ u32 val;
+
+ if (pll_hw->table) {
+ regmap_read(common->regmap, pll_hw->reg, &val);
+
+ val = val >> pll_hw->shift;
+ val &= mul_mask(pll_hw);
+
+ return _get_table_rate(pll_hw->table, val);
+ }
+
+ /* fixed frequency */
+ if (pll_hw->width == 0)
+ return pll_hw->bfreq;
+
+ regmap_read(common->regmap, pll_hw->reg, &val);
+
+ val = val >> pll_hw->shift;
+ val &= mul_mask(pll_hw);
+
+ return pll_hw->bfreq * val;
+}
+
+static int owl_pll_is_enabled(struct clk_hw *hw)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ struct owl_pll_hw *pll_hw = &pll->pll_hw;
+ const struct owl_clk_common *common = &pll->common;
+ u32 reg;
+
+ regmap_read(common->regmap, pll_hw->reg, ®);
+
+ return !!(reg & BIT(pll_hw->bit_idx));
+}
+
+static void owl_pll_set(const struct owl_clk_common *common,
+ const struct owl_pll_hw *pll_hw, bool enable)
+{
+ u32 reg;
+
+ regmap_read(common->regmap, pll_hw->reg, ®);
+
+ if (enable)
+ reg |= BIT(pll_hw->bit_idx);
+ else
+ reg &= ~BIT(pll_hw->bit_idx);
+
+ regmap_write(common->regmap, pll_hw->reg, reg);
+}
+
+static int owl_pll_enable(struct clk_hw *hw)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ const struct owl_clk_common *common = &pll->common;
+
+ owl_pll_set(common, &pll->pll_hw, true);
+
+ return 0;
+}
+
+static void owl_pll_disable(struct clk_hw *hw)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ const struct owl_clk_common *common = &pll->common;
+
+ owl_pll_set(common, &pll->pll_hw, false);
+}
+
+static int owl_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct owl_pll *pll = hw_to_owl_pll(hw);
+ struct owl_pll_hw *pll_hw = &pll->pll_hw;
+ const struct owl_clk_common *common = &pll->common;
+ const struct clk_pll_table *clkt;
+ u32 val, reg;
+
+ /* fixed frequency */
+ if (pll_hw->width == 0)
+ return 0;
+
+ if (pll_hw->table) {
+ clkt = _get_pll_table(pll_hw->table, rate);
+ val = clkt->val;
+ } else {
+ val = owl_pll_calculate_mul(pll_hw, rate);
+ }
+
+ regmap_read(common->regmap, pll_hw->reg, ®);
+
+ reg &= ~mul_mask(pll_hw);
+ reg |= val << pll_hw->shift;
+
+ regmap_write(common->regmap, pll_hw->reg, reg);
+
+ udelay(PLL_STABILITY_WAIT_US);
+
+ return 0;
+}
+
+const struct clk_ops owl_pll_ops = {
+ .enable = owl_pll_enable,
+ .disable = owl_pll_disable,
+ .is_enabled = owl_pll_is_enabled,
+ .round_rate = owl_pll_round_rate,
+ .recalc_rate = owl_pll_recalc_rate,
+ .set_rate = owl_pll_set_rate,
+};
diff --git a/drivers/clk/actions/owl-pll.h b/drivers/clk/actions/owl-pll.h
new file mode 100644
index 000000000000..0aae30abd5dc
--- /dev/null
+++ b/drivers/clk/actions/owl-pll.h
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// OWL pll clock driver
+//
+// Copyright (c) 2014 Actions Semi Inc.
+// Author: David Liu <liuwei at actions-semi.com>
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam at linaro.org>
+
+#ifndef _OWL_PLL_H_
+#define _OWL_PLL_H_
+
+#include "owl-common.h"
+
+/* last entry should have rate = 0 */
+struct clk_pll_table {
+ unsigned int val;
+ unsigned long rate;
+};
+
+struct owl_pll_hw {
+ u32 reg;
+ u32 bfreq;
+ u8 bit_idx;
+ u8 shift;
+ u8 width;
+ u8 min_mul;
+ u8 max_mul;
+ const struct clk_pll_table *table;
+};
+
+struct owl_pll {
+ struct owl_pll_hw pll_hw;
+ struct owl_clk_common common;
+};
+
+#define OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \
+ _width, _min_mul, _max_mul, _table) \
+ { \
+ .reg = _reg, \
+ .bfreq = _bfreq, \
+ .bit_idx = _bit_idx, \
+ .shift = _shift, \
+ .width = _width, \
+ .min_mul = _min_mul, \
+ .max_mul = _max_mul, \
+ .table = _table, \
+ }
+
+#define OWL_PLL(_struct, _name, _parent, _reg, _bfreq, _bit_idx, \
+ _shift, _width, _min_mul, _max_mul, _table, _flags) \
+ struct owl_pll _struct = { \
+ .pll_hw = OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \
+ _width, _min_mul, \
+ _max_mul, _table), \
+ .common = { \
+ .regmap = NULL, \
+ .hw.init = CLK_HW_INIT(_name, \
+ _parent, \
+ &owl_pll_ops, \
+ _flags), \
+ }, \
+ }
+
+#define OWL_PLL_NO_PARENT(_struct, _name, _reg, _bfreq, _bit_idx, \
+ _shift, _width, _min_mul, _max_mul, _table, _flags) \
+ struct owl_pll _struct = { \
+ .pll_hw = OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \
+ _width, _min_mul, \
+ _max_mul, _table), \
+ .common = { \
+ .regmap = NULL, \
+ .hw.init = CLK_HW_INIT_NO_PARENT(_name, \
+ &owl_pll_ops, \
+ _flags), \
+ }, \
+ }
+
+#define mul_mask(m) ((1 << ((m)->width)) - 1)
+#define PLL_STABILITY_WAIT_US (50)
+
+static inline struct owl_pll *hw_to_owl_pll(const struct clk_hw *hw)
+{
+ struct owl_clk_common *common = hw_to_owl_clk_common(hw);
+
+ return container_of(common, struct owl_pll, common);
+}
+
+extern const struct clk_ops owl_pll_ops;
+
+#endif /* _OWL_PLL_H_ */
--
2.14.1
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