[PATCH v3 01/11] clk: samsung: add common clock framework helper functions for Samsung platforms
From: Tomasz Figa <hidden>
Date: 2012-11-14 23:12:21
Also in:
linux-devicetree, linux-samsung-soc
Hi Thomas, Looks mostly good, but I have some minor comments inline. On Thursday 15 of November 2012 03:37:23 Thomas Abraham wrote:
quoted hunk ↗ jump to hunk
All Samsung platforms include different types of clock including fixed-rate, mux, divider and gate clock types. There are typically hundreds of such clocks on each of the Samsung platforms. To enable Samsung platforms to register these clocks using the common clock framework, a bunch of utility functions are introduced here which simplify the clock registration process. The clocks are usually statically instantiated and registered with common clock framework. Cc: Mike Turquette <redacted> Cc: Kukjin Kim <redacted> Signed-off-by: Thomas Abraham <redacted> --- drivers/clk/Makefile | 1 + drivers/clk/samsung/Makefile | 5 + drivers/clk/samsung/clk.c | 176 ++++++++++++++++++++++++++++++++++ drivers/clk/samsung/clk.h | 218 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 400 insertions(+), 0 deletions(-) create mode 100644 drivers/clk/samsung/Makefile create mode 100644 drivers/clk/samsung/clk.c create mode 100644 drivers/clk/samsung/clk.hdiff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 2701235..808f8e1 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile@@ -19,6 +19,7 @@ endif obj-$(CONFIG_MACH_LOONGSON1) += clk-ls1x.o obj-$(CONFIG_ARCH_U8500) += ux500/ obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o +obj-$(CONFIG_PLAT_SAMSUNG) += samsung/ # Chip specific obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.odiff --git a/drivers/clk/samsung/Makefile b/drivers/clk/samsung/Makefile new file mode 100644 index 0000000..3f926b0 --- /dev/null +++ b/drivers/clk/samsung/Makefile@@ -0,0 +1,5 @@ +# +# Samsung Clock specific Makefile +# + +obj-$(CONFIG_PLAT_SAMSUNG) += clk.odiff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c new file mode 100644 index 0000000..ebc6fb6 --- /dev/null +++ b/drivers/clk/samsung/clk.c@@ -0,0 +1,176 @@ +/* + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * Copyright (c) 2012 Linaro Ltd. + * Author: Thomas Abraham <thomas.ab@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as +* published by the Free Software Foundation. + * + * This file includes utility functions to register clocks to common + * clock framework for Samsung platforms. +*/ + +#include "clk.h" + +static DEFINE_SPINLOCK(lock); +static struct clk **clk_table; +static struct clk_onecell_data clk_data; +void __iomem *reg_base;
Shouldn't it be static?
+
+/* setup the essentials required to support clock lookup using ccf */
+void __init samsung_clk_init(struct device_node *np, void __iomem
*base, + unsigned long nr_clks)
+{
+ reg_base = base;
+ if (!np)
+ return;
+
+ clk_table = kzalloc(sizeof(struct clk *) * nr_clks, GFP_KERNEL);
+ if (!clk_table)
+ panic("could not allocate clock lookup table\n");
+
+ clk_data.clks = clk_table;
+ clk_data.clk_num = nr_clks;
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+/* add a clock instance to the clock lookup table used for dt based
lookup */ +void samsung_clk_add_lookup(struct clk *clk, unsigned int
id) +{
+ if (clk_table && id)I'm not sure if we really need this kind of checks, but if we do, then shouldn't we also check id against clk_data.clk_num to prevent out of bound index?
+ clk_table[id] = clk;
+}
+
+/* register a list of fixed clocks */
+void __init samsung_clk_register_fixed_rate(
+ struct samsung_fixed_rate_clock *list, unsigned int nr_clk)
+{
+ struct clk *clk;
+ unsigned int idx, ret;
+
+ for (idx = 0; idx < nr_clk; idx++, list++) {
+ clk = clk_register_fixed_rate(NULL, list->name,
+ list->parent_name, list->flags, list->fixed_rate);
+ if (IS_ERR(clk)) {
+ pr_err("%s: failed to register clock %s\n", __func__,
+ list->name);
+ continue;
+ }
+
+ samsung_clk_add_lookup(clk, list->id);
+
+ /*
+ * Unconditionally add a clock lookup for the fixed rate clocks.
+ * There are not many of these on any of Samsung platforms.
+ */
+ ret = clk_register_clkdev(clk, list->name, NULL);
+ if (ret)
+ pr_err("%s: failed to register clock lookup for %s",
+ __func__, list->name);
+ }
+}
+
+/* register a list of mux clocks */
+void __init samsung_clk_register_mux(struct samsung_mux_clock *list,
+ unsigned int nr_clk)
+{
+ struct clk *clk;
+ unsigned int idx, ret;
+
+ for (idx = 0; idx < nr_clk; idx++, list++) {
+ clk = clk_register_mux(NULL, list->name, list->parent_names,
+ list->num_parents, list->flags, reg_base + list->offset,
+ list->shift, list->width, list->mux_flags, &lock);
+ if (IS_ERR(clk)) {
+ pr_err("%s: failed to register clock %s\n", __func__,
+ list->name);
+ continue;
+ }
+
+ samsung_clk_add_lookup(clk, list->id);
+
+ /* register a clock lookup only if a clock alias is specified */
+ if (list->alias) {
+ ret = clk_register_clkdev(clk, list->alias,
+ list->dev_name);
+ if (ret)
+ pr_err("%s: failed to register lookup %s\n",
+ __func__, list->alias);
+ }
+ }
+}
+
+/* register a list of div clocks */
+void __init samsung_clk_register_div(struct samsung_div_clock *list,
+ unsigned int nr_clk)
+{
+ struct clk *clk;
+ unsigned int idx, ret;
+
+ for (idx = 0; idx < nr_clk; idx++, list++) {
+ clk = clk_register_divider(NULL, list->name, list-
parent_name,
+ list->flags, reg_base + list->offset, list->shift,
+ list->width, list->div_flags, &lock);
+ if (IS_ERR(clk)) {
+ pr_err("clock: failed to register clock %s\n",
+ list->name);
+ continue;
+ }
+
+ samsung_clk_add_lookup(clk, list->id);
+
+ /* register a clock lookup only if a clock alias is specified */
+ if (list->alias) {
+ ret = clk_register_clkdev(clk, list->alias,
+ list->dev_name);
+ if (ret)
+ pr_err("%s: failed to register lookup %s\n",
+ __func__, list->alias);
+ }
+ }
+}
+
+/* register a list of gate clocks */
+void __init samsung_clk_register_gate(struct samsung_gate_clock *list,
+ unsigned int nr_clk)
+{
+ struct clk *clk;
+ unsigned int idx, ret;
+
+ for (idx = 0; idx < nr_clk; idx++, list++) {
+ clk = clk_register_gate(NULL, list->name, list->parent_name,
+ list->flags, reg_base + list->offset,
+ list->bit_idx, list->gate_flags, &lock);
+ if (IS_ERR(clk)) {
+ pr_err("clock: failed to register clock %s\n",
+ list->name);
+ continue;
+ }
+
+ /* register a clock lookup only if a clock alias is specified */
quoted hunk ↗ jump to hunk
+ if (list->alias) { + ret = clk_register_clkdev(clk, list->alias, + list->dev_name); + if (ret) + pr_err("%s: failed to register lookup %s\n", + __func__, list->alias); + } + + samsung_clk_add_lookup(clk, list->id); + } +} + +/* utility function to get the rate of a specified clock */ +unsigned long _get_rate(const char *clk_name) +{ + struct clk *clk; + unsigned long rate; + + clk = clk_get(NULL, clk_name); + if (IS_ERR(clk)) + return 0; + rate = clk_get_rate(clk); + clk_put(clk); + return rate; +}diff --git a/drivers/clk/samsung/clk.h b/drivers/clk/samsung/clk.h new file mode 100644 index 0000000..ab43498 --- /dev/null +++ b/drivers/clk/samsung/clk.h@@ -0,0 +1,218 @@ +/* + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * Copyright (c) 2012 Linaro Ltd. + * Author: Thomas Abraham <thomas.ab@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as +* published by the Free Software Foundation. + * + * Common Clock Framework support for all Samsung platforms +*/ + +#ifndef __SAMSUNG_CLK_H +#define __SAMSUNG_CLK_H + +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/io.h> +#include <linux/clk-provider.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <mach/map.h> + +/** + * struct samsung_fixed_rate_clock: information about fixed-rate clock + * @id: platform specific id of the clock. + * @name: name of this fixed-rate clock. + * @parent_name: optional parent clock name. + * @flags: optional fixed-rate clock flags. + * @fixed-rate: fixed clock rate of this clock. + */ +struct samsung_fixed_rate_clock { + unsigned int id; + char *name;
Shouldn't it be const char *name?
+ const char *parent_name;
+ unsigned long flags;
+ unsigned long fixed_rate;
+};
+
+#define FRATE(_id, cname, pname, f, frate) \
+ { \
+ .id = _id, \
+ .name = cname, \
+ .parent_name = pname, \
+ .flags = f, \
+ .fixed_rate = frate, \
+ }
+
+/**
+ * struct samsung_mux_clock: information about mux clock
+ * @id: platform specific id of the clock.
+ * @dev_name: name of the device to which this clock belongs.
+ * @name: name of this mux clock.
+ * @parent_names: array of pointer to parent clock names.
+ * @num_parents: number of parents listed in @parent_names.
+ * @flags: optional flags for basic clock.
+ * @offset: offset of the register for configuring the mux.
+ * @shift: starting bit location of the mux control bit-field in @reg.
+ * @width: width of the mux control bit-field in @reg.
+ * @mux_flags: flags for mux-type clock.
+ * @alias: optional clock alias name to be assigned to this clock.
+ */
+struct samsung_mux_clock {
+ const unsigned int id;Is const unsigned int really correct?
+ const char *dev_name;
+ const char *name;
+ const char **parent_names;
+ u8 num_parents;
+ unsigned long flags;
+ unsigned long offset;
+ u8 shift;
+ u8 width;
+ u8 mux_flags;
+ const char *alias;
+};
+
+#define __MUX(_id, dname, cname, pnames, o, s, w, f, mf, a) \
+ { \
+ .id = _id, \
+ .dev_name = dname, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .offset = o, \
+ .shift = s, \
+ .width = w, \
+ .mux_flags = mf, \
+ .alias = a, \
+ }
+
+#define MUX(_id, cname, pnames, o, s, w) \
+ __MUX(_id, NULL, cname, pnames, o, s, w, 0, 0, NULL)
+
+#define MUX_A(_id, cname, pnames, o, s, w, a) \
+ __MUX(_id, NULL, cname, pnames, o, s, w, 0, 0, a)
+
+#define MUX_F(_id, cname, pnames, o, s, w, f, mf) \
+ __MUX(_id, NULL, cname, pnames, o, s, w, f, mf, NULL)
+
+/**
+ * @id: platform specific id of the clock.
+ * struct samsung_div_clock: information about div clock
+ * @dev_name: name of the device to which this clock belongs.
+ * @name: name of this div clock.
+ * @parent_name: name of the parent clock.
+ * @flags: optional flags for basic clock.
+ * @offset: offset of the register for configuring the div.
+ * @shift: starting bit location of the div control bit-field in @reg.
+ * @div_flags: flags for div-type clock.
+ * @alias: optional clock alias name to be assigned to this clock.
+ */
+struct samsung_div_clock {
+ const unsigned int id;ditto
+ const char *dev_name;
+ const char *name;
+ const char *parent_name;
+ unsigned long flags;
+ unsigned long offset;
+ u8 shift;
+ u8 width;
+ u8 div_flags;
+ const char *alias;
+};
+
+#define __DIV(_id, dname, cname, pname, o, s, w, f, df, a) \
+ { \
+ .id = _id, \
+ .dev_name = dname, \
+ .name = cname, \
+ .parent_name = pname, \
+ .flags = f, \
+ .offset = o, \
+ .shift = s, \
+ .width = w, \
+ .div_flags = df, \
+ .alias = a, \
+ }
+
+#define DIV(_id, cname, pname, o, s, w) \
+ __DIV(_id, NULL, cname, pname, o, s, w, 0, 0, NULL)
+
+#define DIV_A(_id, cname, pname, o, s, w, a) \
+ __DIV(_id, NULL, cname, pname, o, s, w, 0, 0, a)
+
+#define DIV_F(_id, cname, pname, o, s, w, f, df) \
+ __DIV(_id, NULL, cname, pname, o, s, w, f, df, NULL)
+
+/**
+ * struct samsung_gate_clock: information about gate clock
+ * @id: platform specific id of the clock.
+ * @dev_name: name of the device to which this clock belongs.
+ * @name: name of this gate clock.
+ * @parent_name: name of the parent clock.
+ * @flags: optional flags for basic clock.
+ * @offset: offset of the register for configuring the gate.
+ * @bit_idx: bit index of the gate control bit-field in @reg.
+ * @gate_flags: flags for gate-type clock.
+ * @alias: optional clock alias name to be assigned to this clock.
+ */
+struct samsung_gate_clock {
+ const unsigned int id;ditto
+ const char *dev_name;
+ const char *name;
+ const char *parent_name;
+ unsigned long flags;
+ unsigned long offset;
+ u8 bit_idx;
+ u8 gate_flags;
+ const char *alias;
+};
+
+#define __GATE(_id, dname, cname, pname, o, b, f, gf, a) \
+ { \
+ .id = _id, \
+ .dev_name = dname, \
+ .name = cname, \
+ .parent_name = pname, \
+ .flags = f, \
+ .offset = o, \
+ .bit_idx = b, \
+ .gate_flags = gf, \
+ .alias = a, \
+ }
+
+#define GATE(_id, cname, pname, o, b, f, gf) \
+ __GATE(_id, NULL, cname, pname, o, b, f, gf, NULL)
+
+#define GATE_A(_id, cname, pname, o, b, f, gf, a) \
+ __GATE(_id, NULL, cname, pname, o, b, f, gf, a)
+
+#define GATE_D(_id, dname, cname, pname, o, b, f, gf) \
+ __GATE(_id, dname, cname, pname, o, b, f, gf, NULL)
+
+#define GATE_DA(_id, dname, cname, pname, o, b, f, gf, a) \
+ __GATE(_id, dname, cname, pname, o, b, f, gf, a)
+
+#define PNAME(x) static const char *x[] __initdata
+
+extern void __iomem *reg_base;Where is it used? The name suggests that it should rather be static. -- Best regards, Tomasz Figa