clk: sunxi-ng: Add divider

Add support for the various dividers (linear, table or pow-of-two based)
found in the CCU.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20160629190535.11855-8-maxime.ripard@free-electrons.com

diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig
index 3a3bc4368a2a1e5e5374aebf229c1e86f72b576f..7e65e776e7a8f3b3e795170bcb6e74a73cb2259a 100644 (file)
--- a/drivers/clk/sunxi-ng/Kconfig
+++ b/drivers/clk/sunxi-ng/Kconfig
@@ -6,6 +6,10 @@ if SUNXI_CCU
 
 # Base clock types
 
+config SUNXI_CCU_DIV
+       bool
+       select SUNXI_CCU_MUX
+
 config SUNXI_CCU_FRAC
        bool
 

diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index a0c53c56ebfe2d8acab3755ea3ed19d3da3446a7..4bc5b6168560ac5ba004b24c8cb4e30defd942cf 100644 (file)
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_SUNXI_CCU)         += ccu_common.o
 obj-$(CONFIG_SUNXI_CCU)                += ccu_reset.o
 
 # Base clock types
+obj-$(CONFIG_SUNXI_CCU_DIV)    += ccu_div.o
 obj-$(CONFIG_SUNXI_CCU_FRAC)   += ccu_frac.o
 obj-$(CONFIG_SUNXI_CCU_GATE)   += ccu_gate.o
 obj-$(CONFIG_SUNXI_CCU_MUX)    += ccu_mux.o

diff --git a/drivers/clk/sunxi-ng/ccu_div.c b/drivers/clk/sunxi-ng/ccu_div.c
new file mode 100644 (file)
index 0000000..8659b4c
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_div.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * 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.
+ */
+
+#include <linux/clk-provider.h>
+
+#include "ccu_gate.h"
+#include "ccu_div.h"
+
+static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
+                                       unsigned long parent_rate,
+                                       unsigned long rate,
+                                       void *data)
+{
+       struct ccu_div *cd = data;
+       unsigned long val;
+
+       /*
+        * We can't use divider_round_rate that assumes that there's
+        * several parents, while we might be called to evaluate
+        * several different parents.
+        */
+       val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
+                             cd->div.flags);
+
+       return divider_recalc_rate(&cd->common.hw, parent_rate, val,
+                                  cd->div.table, cd->div.flags);
+}
+
+static void ccu_div_disable(struct clk_hw *hw)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_gate_helper_disable(&cd->common, cd->enable);
+}
+
+static int ccu_div_enable(struct clk_hw *hw)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_gate_helper_enable(&cd->common, cd->enable);
+}
+
+static int ccu_div_is_enabled(struct clk_hw *hw)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
+}
+
+static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
+                                       unsigned long parent_rate)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+       unsigned long val;
+       u32 reg;
+
+       reg = readl(cd->common.base + cd->common.reg);
+       val = reg >> cd->div.shift;
+       val &= (1 << cd->div.width) - 1;
+
+       ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
+                                               &parent_rate);
+
+       return divider_recalc_rate(hw, parent_rate, val, cd->div.table,
+                                  cd->div.flags);
+}
+
+static int ccu_div_determine_rate(struct clk_hw *hw,
+                               struct clk_rate_request *req)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
+                                            req, ccu_div_round_rate, cd);
+}
+
+static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
+                          unsigned long parent_rate)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+       unsigned long flags;
+       unsigned long val;
+       u32 reg;
+
+       ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
+                                               &parent_rate);
+
+       val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
+                             cd->div.flags);
+
+       spin_lock_irqsave(cd->common.lock, flags);
+
+       reg = readl(cd->common.base + cd->common.reg);
+       reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
+
+       writel(reg | (val << cd->div.shift),
+              cd->common.base + cd->common.reg);
+
+       spin_unlock_irqrestore(cd->common.lock, flags);
+
+       return 0;
+}
+
+static u8 ccu_div_get_parent(struct clk_hw *hw)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
+}
+
+static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
+{
+       struct ccu_div *cd = hw_to_ccu_div(hw);
+
+       return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
+}
+
+const struct clk_ops ccu_div_ops = {
+       .disable        = ccu_div_disable,
+       .enable         = ccu_div_enable,
+       .is_enabled     = ccu_div_is_enabled,
+
+       .get_parent     = ccu_div_get_parent,
+       .set_parent     = ccu_div_set_parent,
+
+       .determine_rate = ccu_div_determine_rate,
+       .recalc_rate    = ccu_div_recalc_rate,
+       .set_rate       = ccu_div_set_rate,
+};

diff --git a/drivers/clk/sunxi-ng/ccu_div.h b/drivers/clk/sunxi-ng/ccu_div.h
new file mode 100644 (file)
index 0000000..653ade5
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_div.h
@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2016 Maxime Ripard. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#ifndef _CCU_DIV_H_
+#define _CCU_DIV_H_
+
+#include <linux/clk-provider.h>
+
+#include "ccu_common.h"
+#include "ccu_mux.h"
+
+struct _ccu_div {
+       u8                      shift;
+       u8                      width;
+
+       u32                     flags;
+
+       struct clk_div_table    *table;
+};
+
+#define _SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, _table, _flags)     \
+       {                                                               \
+               .shift  = _shift,                                       \
+               .width  = _width,                                       \
+               .flags  = _flags,                                       \
+               .table  = _table,                                       \
+       }
+
+#define _SUNXI_CCU_DIV_FLAGS(_shift, _width, _flags)                   \
+       _SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, NULL, _flags)
+
+#define _SUNXI_CCU_DIV_TABLE(_shift, _width, _table)                   \
+       _SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, _table, 0)
+
+#define _SUNXI_CCU_DIV(_shift, _width)                                 \
+       _SUNXI_CCU_DIV_TABLE_FLAGS(_shift, _width, NULL, 0)
+
+struct ccu_div {
+       u32                     enable;
+
+       struct _ccu_div         div;
+       struct ccu_mux_internal mux;
+       struct ccu_common       common;
+};
+
+#define SUNXI_CCU_DIV_TABLE_WITH_GATE(_struct, _name, _parent, _reg,   \
+                                     _shift, _width,                   \
+                                     _table, _gate, _flags)            \
+       struct ccu_div _struct = {                                      \
+               .div            = _SUNXI_CCU_DIV_TABLE(_shift, _width,  \
+                                                      _table),         \
+               .enable         = _gate,                                \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .hw.init        = CLK_HW_INIT(_name,            \
+                                                     _parent,          \
+                                                     &ccu_div_ops,     \
+                                                     _flags),          \
+               }                                                       \
+       }
+
+
+#define SUNXI_CCU_DIV_TABLE(_struct, _name, _parent, _reg,             \
+                           _shift, _width,                             \
+                           _table, _flags)                             \
+       SUNXI_CCU_DIV_TABLE_WITH_GATE(_struct, _name, _parent, _reg,    \
+                                     _shift, _width, _table, 0,        \
+                                     _flags)
+
+#define SUNXI_CCU_M_WITH_MUX_GATE(_struct, _name, _parents, _reg,      \
+                                 _mshift, _mwidth, _muxshift, _muxwidth, \
+                                 _gate, _flags)                        \
+       struct ccu_div _struct = {                                      \
+               .enable = _gate,                                        \
+               .div    = _SUNXI_CCU_DIV(_mshift, _mwidth),             \
+               .mux    = SUNXI_CLK_MUX(_muxshift, _muxwidth),          \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .hw.init        = CLK_HW_INIT_PARENTS(_name,    \
+                                                             _parents, \
+                                                             &ccu_div_ops, \
+                                                             _flags),  \
+               },                                                      \
+       }
+
+#define SUNXI_CCU_M_WITH_MUX(_struct, _name, _parents, _reg,           \
+                            _mshift, _mwidth, _muxshift, _muxwidth,    \
+                            _flags)                                    \
+       SUNXI_CCU_M_WITH_MUX_GATE(_struct, _name, _parents, _reg,       \
+                                 _mshift, _mwidth, _muxshift, _muxwidth, \
+                                 0, _flags)
+
+
+#define SUNXI_CCU_M_WITH_GATE(_struct, _name, _parent, _reg,           \
+                             _mshift, _mwidth, _gate,                  \
+                             _flags)                                   \
+       struct ccu_div _struct = {                                      \
+               .enable = _gate,                                        \
+               .div    = _SUNXI_CCU_DIV(_mshift, _mwidth),             \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .hw.init        = CLK_HW_INIT(_name,            \
+                                                     _parent,          \
+                                                     &ccu_div_ops,     \
+                                                     _flags),          \
+               },                                                      \
+       }
+
+#define SUNXI_CCU_M(_struct, _name, _parent, _reg, _mshift, _mwidth,   \
+                   _flags)                                             \
+       SUNXI_CCU_M_WITH_GATE(_struct, _name, _parent, _reg,            \
+                             _mshift, _mwidth, 0, _flags)
+
+static inline struct ccu_div *hw_to_ccu_div(struct clk_hw *hw)
+{
+       struct ccu_common *common = hw_to_ccu_common(hw);
+
+       return container_of(common, struct ccu_div, common);
+}
+
+extern const struct clk_ops ccu_div_ops;
+
+#endif /* _CCU_DIV_H_ */