Thread (64 messages) 64 messages, 4 authors, 2016-06-03

[PATCH 08/16] clk: sunxi-ng: Add M-factor clock support

From: Chen-Yu Tsai <hidden>
Date: 2016-05-21 17:09:09
Also in: linux-clk

Hi,

On Mon, May 9, 2016 at 4:01 AM, Maxime Ripard
[off-list ref] wrote:
Introduce support for clocks that divide by a linear factor.
I think we can have just one implementation for single divide factor
(either P or M)
clocks, using the CCF divider helpers. Even the divider table clock
could be merged
in.
quoted hunk ↗ jump to hunk
Signed-off-by: Maxime Ripard <redacted>
---
 drivers/clk/sunxi-ng/Makefile |   1 +
 drivers/clk/sunxi-ng/ccu_m.c  | 135 ++++++++++++++++++++++++++++++++++++++++++
 drivers/clk/sunxi-ng/ccu_m.h  | 101 +++++++++++++++++++++++++++++++
 3 files changed, 237 insertions(+)
 create mode 100644 drivers/clk/sunxi-ng/ccu_m.c
 create mode 100644 drivers/clk/sunxi-ng/ccu_m.h
diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index a47a3bbdf285..f41de901c607 100644
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile
@@ -4,5 +4,6 @@ obj-y += ccu_reset.o
 obj-y += ccu_div_table.o
 obj-y += ccu_fixed_factor.o
 obj-y += ccu_gate.o
+obj-y += ccu_m.o
 obj-y += ccu_mux.o
 obj-y += ccu_phase.o
diff --git a/drivers/clk/sunxi-ng/ccu_m.c b/drivers/clk/sunxi-ng/ccu_m.c
new file mode 100644
index 000000000000..424eb6da0d5b
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_m.c
@@ -0,0 +1,135 @@
+/*
+ * 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_m.h"
+#include "ccu_mux.h"
+
+static void ccu_m_find_best(unsigned long parent, unsigned long rate,
+                           unsigned int max_m, unsigned int *m)
+{
+       unsigned int _m = parent / rate;
+
+       if (_m > max_m)
+               _m = max_m;
+
+       *m = _m;
+}
This can go.
+
+static unsigned long ccu_m_round_rate(struct ccu_mux_internal *mux,
+                                      unsigned long parent_rate,
+                                      unsigned long rate,
+                                      void *data)
+{
+       struct ccu_m *cm = data;
+       unsigned int m;
+
+       ccu_m_find_best(parent_rate, rate, 1 << cm->m.width, &m);
+
+       return parent_rate / m;
Use divider_round_rate() helper instead.
+}
+
+
+static void ccu_m_disable(struct clk_hw *hw)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_gate_helper_disable(&cm->common, cm->enable);
+}
+
+static int ccu_m_enable(struct clk_hw *hw)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_gate_helper_enable(&cm->common, cm->enable);
+}
+
+static int ccu_m_is_enabled(struct clk_hw *hw)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_gate_helper_is_enabled(&cm->common, cm->enable);
+}
+
+static unsigned long ccu_m_recalc_rate(struct clk_hw *hw,
+                                      unsigned long parent_rate)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+       unsigned long m;
+       u32 reg;
+
+       reg = readl(cm->common.base + cm->common.reg);
+
+       m = reg >> cm->m.shift;
+       m &= (1 << cm->m.width) - 1;
+
+       return parent_rate / (m + 1);
Use divider_recalc_rate() helper.
+}
+
+static int ccu_m_determine_rate(struct clk_hw *hw,
+                               struct clk_rate_request *req)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_mux_helper_determine_rate(&cm->common, &cm->mux,
+                                            req, ccu_m_round_rate, cm);
+}
+
+static int ccu_m_set_rate(struct clk_hw *hw, unsigned long rate,
+                         unsigned long parent_rate)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+       unsigned long flags;
+       unsigned int m;
+       u32 reg;
+
+       ccu_m_find_best(parent_rate, rate, 1 << cm->m.width, &m);
Use divider_get_val() helper.
quoted hunk ↗ jump to hunk
+
+       spin_lock_irqsave(cm->common.lock, flags);
+
+       reg = readl(cm->common.base + cm->common.reg);
+       reg &= ((1 << cm->m.width) - 1) << cm->m.shift;
+
+       writel(reg | ((m - 1) << cm->m.shift),
+              cm->common.base + cm->common.reg);
+
+       spin_unlock_irqrestore(cm->common.lock, flags);
+
+       return 0;
+}
+
+static u8 ccu_m_get_parent(struct clk_hw *hw)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_mux_helper_get_parent(&cm->common, &cm->mux);
+}
+
+static int ccu_m_set_parent(struct clk_hw *hw, u8 index)
+{
+       struct ccu_m *cm = hw_to_ccu_m(hw);
+
+       return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index);
+}
+
+const struct clk_ops ccu_m_ops = {
+       .disable        = ccu_m_disable,
+       .enable         = ccu_m_enable,
+       .is_enabled     = ccu_m_is_enabled,
+
+       .get_parent     = ccu_m_get_parent,
+       .set_parent     = ccu_m_set_parent,
+
+       .determine_rate = ccu_m_determine_rate,
+       .recalc_rate    = ccu_m_recalc_rate,
+       .set_rate       = ccu_m_set_rate,
+};
diff --git a/drivers/clk/sunxi-ng/ccu_m.h b/drivers/clk/sunxi-ng/ccu_m.h
new file mode 100644
index 000000000000..625c0a7cef43
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_m.h
@@ -0,0 +1,101 @@
+/*
+ * 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_M_H_
+#define _CCU_M_H_
+
+#include <linux/clk-provider.h>
+
+#include "ccu_common.h"
+#include "ccu_factor.h"
+#include "ccu_mux.h"
+
+struct ccu_m {
+       u32                     enable;
Add a field for divider flags, such as CLK_DIVIDER_ONE_BASED and
CLK_DIVIDER_POWER_OF_TWO. With these we can merge P & M factor clocks,
and also be able to handle M factors starting from both 1 and 0.

Also add a field for divider tables to merge the divider table clock.
+
+       struct ccu_factor       m;
+       struct ccu_mux_internal mux;
+       struct ccu_common       common;
+};
+
+#define SUNXI_CCU_M(_struct, _name, _parent, _reg, _mshift, _mwidth,   \
+                   _flags)                                             \
+       struct ccu_m _struct = {                                        \
+               .m      = SUNXI_CLK_FACTOR(_mshift, _mwidth),           \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .hw.init        = SUNXI_HW_INIT(_name,          \
+                                                       _parent,        \
+                                                       &ccu_m_ops,     \
+                                                       _flags),        \
+               },                                                      \
+       }
+
+#define SUNXI_CCU_M_WITH_GATE(_struct, _name, _parent, _reg,           \
+                             _mshift, _mwidth, _gate,                  \
+                             _flags)                                   \
+       struct ccu_m _struct = {                                        \
+               .enable = _gate,                                        \
+               .m      = SUNXI_CLK_FACTOR(_mshift, _mwidth),           \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .features       = CCU_FEATURE_GATE,             \
+                       .hw.init        = SUNXI_HW_INIT(_name,          \
+                                                       _parent,        \
+                                                       &ccu_m_ops,     \
+                                                       _flags),        \
+               },                                                      \
+       }
+
+#define SUNXI_CCU_M_WITH_MUX(_struct, _name, _parents, _reg,           \
+                            _mshift, _mwidth, _muxshift, _muxwidth,    \
+                            _flags)                                    \
+       struct ccu_m _struct = {                                        \
+               .m      = SUNXI_CLK_FACTOR(_mshift, _mwidth),           \
+               .mux    = SUNXI_CLK_MUX(_muxshift, _muxwidth),          \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .hw.init        = SUNXI_HW_INIT_PARENTS(_name,  \
+                                                               _parents, \
+                                                               &ccu_m_ops, \
+                                                               _flags), \
+               },                                                      \
+       }
Maybe you could use the full macro below to simplify the above 3, with
the unused fields set to 0?


Regards
ChenYu
+
+#define SUNXI_CCU_M_WITH_MUX_GATE(_struct, _name, _parents, _reg,      \
+                                 _mshift, _mwidth, _muxshift, _muxwidth, \
+                                 _gate, _flags)                        \
+       struct ccu_m _struct = {                                        \
+               .enable = _gate,                                        \
+               .m      = SUNXI_CLK_FACTOR(_mshift, _mwidth),           \
+               .mux    = SUNXI_CLK_MUX(_muxshift, _muxwidth),          \
+               .common = {                                             \
+                       .reg            = _reg,                         \
+                       .features       = CCU_FEATURE_GATE,             \
+                       .hw.init        = SUNXI_HW_INIT_PARENTS(_name,  \
+                                                               _parents, \
+                                                               &ccu_m_ops, \
+                                                               _flags), \
+               },                                                      \
+       }
+
+static inline struct ccu_m *hw_to_ccu_m(struct clk_hw *hw)
+{
+       struct ccu_common *common = hw_to_ccu_common(hw);
+
+       return container_of(common, struct ccu_m, common);
+}
+
+extern const struct clk_ops ccu_m_ops;
+
+#endif /* _CCU_M_H_ */
--
2.8.2
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help