clk: rockchip: add basic infrastructure for clock branches

A patch from »Clock support for rk3066,rk3188 and rk3288« in state Mainline for linux-kernel

From: Heiko Stuebner <heiko@...> Date: Thu, 10 Apr 2014 14:38:24 +0200

Commit-Message

This adds infrastructure for registering clock branches. On Rockchip SoCs most clock branches are a combination of mux,divider and gate components, thus a composite clock is used when appropriate. Clock branches are supposed to be declared in an array using the COMPOSITE* or MUX, etc makros defined in the header and then registered using rockchip_clk_register_branches. Signed-off-by: Heiko Stuebner <heiko@...> Acked-By: Max Schwarz <max.schwarz@...> Tested-By: Max Schwarz <max.schwarz@...>

Patch-Comment

drivers/clk/rockchip/Makefile | 1 + drivers/clk/rockchip/clk.c | 209 +++++++++++++++++++++++++++++++++++ drivers/clk/rockchip/clk.h | 250 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 460 insertions(+) create mode 100644 drivers/clk/rockchip/clk.c create mode 100644 drivers/clk/rockchip/clk.h

Statistics

  • 460 lines added
  • 0 lines removed

Changes

------------------------ drivers/clk/rockchip/Makefile -------------------------
index 8d3aefa..0068a8b 100644
@@ -3,3 +3,4 @@
#
obj-y += clk-rockchip.o
+obj-y += clk.o
-------------------------- drivers/clk/rockchip/clk.c --------------------------
new file mode 100644
index 0000000..aa15d5a
@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2014 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ *
+ * based on
+ *
+ * samsung/clk.c
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2013 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 as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ */
+
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include "clk.h"
+
+/**
+ * Register a clock branch.
+ * Most clock branches have a form like
+ *
+ * src1 --|--\
+ * |M |--[GATE]-[DIV]-
+ * src2 --|--/
+ *
+ * sometimes without one of those components.
+ */
+struct clk *rockchip_clk_register_branch(const char *name,
+ const char **parent_names, u8 num_parents, void __iomem *base,
+ int muxdiv_offset, u8 mux_shift, u8 mux_width, u8 mux_flags,
+ u8 div_shift, u8 div_width, u8 div_flags,
+ struct clk_div_table *div_table, int gate_offset,
+ u8 gate_shift, u8 gate_flags, unsigned long flags,
+ spinlock_t *lock)
+{
+ struct clk *clk;
+ struct clk_mux *mux = NULL;
+ struct clk_gate *gate = NULL;
+ struct clk_divider *div = NULL;
+ const struct clk_ops *mux_ops = NULL, *div_ops = NULL,
+ *gate_ops = NULL;
+
+ if (num_parents > 1) {
+ mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return ERR_PTR(-ENOMEM);
+
+ mux->reg = base + muxdiv_offset;
+ mux->shift = mux_shift;
+ mux->mask = BIT(mux_width) - 1;
+ mux->flags = mux_flags;
+ mux->lock = lock;
+ mux_ops = (mux_flags & CLK_MUX_READ_ONLY) ? &clk_mux_ro_ops
+ : &clk_mux_ops;
+ }
+
+ if (gate_offset >= 0) {
+ gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+ if (!gate)
+ return ERR_PTR(-ENOMEM);
+
+ gate->flags = gate_flags;
+ gate->reg = base + gate_offset;
+ gate->bit_idx = gate_shift;
+ gate->lock = lock;
+ gate_ops = &clk_gate_ops;
+ }
+
+ if (div_width > 0) {
+ div = kzalloc(sizeof(*div), GFP_KERNEL);
+ if (!div)
+ return ERR_PTR(-ENOMEM);
+
+ div->flags = div_flags;
+ div->reg = base + muxdiv_offset;
+ div->shift = div_shift;
+ div->width = div_width;
+ div->lock = lock;
+ div->table = div_table;
+ div_ops = (div_flags & CLK_DIVIDER_READ_ONLY)
+ ? &clk_divider_ro_ops
+ : &clk_divider_ops;
+ }
+
+ clk = clk_register_composite(NULL, name, parent_names, num_parents,
+ mux ? &mux->hw : NULL, mux_ops,
+ div ? &div->hw : NULL, div_ops,
+ gate ? &gate->hw : NULL, gate_ops,
+ flags);
+
+ return clk;
+}
+
+static DEFINE_SPINLOCK(clk_lock);
+static struct clk **clk_table;
+static void __iomem *reg_base;
+static struct clk_onecell_data clk_data;
+
+void __init rockchip_clk_init(struct device_node *np, void __iomem *base,
+ unsigned long nr_clks)
+{
+ reg_base = base;
+
+ clk_table = kcalloc(nr_clks, sizeof(struct clk *), GFP_KERNEL);
+ if (!clk_table)
+ pr_err("%s: could not allocate clock lookup table\n", __func__);
+
+ clk_data.clks = clk_table;
+ clk_data.clk_num = nr_clks;
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+void rockchip_clk_add_lookup(struct clk *clk, unsigned int id)
+{
+ if (clk_table && id)
+ clk_table[id] = clk;
+}
+
+void __init rockchip_clk_register_branches(
+ struct rockchip_clk_branch *list,
+ unsigned int nr_clk)
+{
+ struct clk *clk = NULL;
+ unsigned int idx;
+ unsigned long flags;
+
+ for (idx = 0; idx < nr_clk; idx++, list++) {
+ flags = list->flags;
+
+ /* catch simple muxes */
+ switch (list->branch_type) {
+ case branch_mux:
+ clk = clk_register_mux(NULL, list->name,
+ list->parent_names, list->num_parents,
+ flags, reg_base + list->muxdiv_offset,
+ list->mux_shift, list->mux_width,
+ list->mux_flags, &clk_lock);
+ break;
+ case branch_divider:
+ if (list->div_table)
+ clk = clk_register_divider_table(NULL,
+ list->name, list->parent_names[0],
+ flags, reg_base + list->muxdiv_offset,
+ list->div_shift, list->div_width,
+ list->div_flags, list->div_table,
+ &clk_lock);
+ else
+ clk = clk_register_divider(NULL, list->name,
+ list->parent_names[0], flags,
+ reg_base + list->muxdiv_offset,
+ list->div_shift, list->div_width,
+ list->div_flags, &clk_lock);
+ break;
+ case branch_fraction_divider:
+ /* unimplemented */
+ continue;
+ break;
+ case branch_gate:
+ flags |= CLK_SET_RATE_PARENT;
+
+ /* keep all gates untouched for now */
+ flags |= CLK_IGNORE_UNUSED;
+
+ clk = clk_register_gate(NULL, list->name,
+ list->parent_names[0], flags,
+ reg_base + list->gate_offset,
+ list->gate_shift, list->gate_flags, &clk_lock);
+ break;
+ case branch_composite:
+ /* keep all gates untouched for now */
+ flags |= CLK_IGNORE_UNUSED;
+
+ clk = rockchip_clk_register_branch(list->name,
+ list->parent_names, list->num_parents,
+ reg_base, list->muxdiv_offset, list->mux_shift,
+ list->mux_width, list->mux_flags,
+ list->div_shift, list->div_width,
+ list->div_flags, list->div_table,
+ list->gate_offset, list->gate_shift,
+ list->gate_flags, flags, &clk_lock);
+ break;
+ }
+
+ /* none of the cases above matched */
+ if (!clk) {
+ pr_err("%s: unknown clock type %d\n",
+ __func__, list->branch_type);
+ continue;
+ }
+
+ if (IS_ERR(clk)) {
+ pr_err("%s: failed to register clock %s: %ld\n",
+ __func__, list->name, PTR_ERR(clk));
+ continue;
+ }
+
+ rockchip_clk_add_lookup(clk, list->id);
+ }
+}
-------------------------- drivers/clk/rockchip/clk.h --------------------------
new file mode 100644
index 0000000..5b051b0
@@ -0,0 +1,250 @@
+/*
+ * Copyright (c) 2014 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ *
+ * based on
+ *
+ * samsung/clk.h
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Copyright (c) 2013 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 as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 CLK_ROCKCHIP_CLK_H
+#define CLK_ROCKCHIP_CLK_H
+
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+
+#define HIWORD_UPDATE(val, mask, shift) \
+ ((val) << (shift) | (mask) << ((shift) + 16))
+
+/* register positions shared by RK2928, RK3066 and RK3188 */
+#define RK2928_PLL_CON(x) (x * 0x4)
+#define RK2928_MODE_CON 0x40
+#define RK2928_CLKSEL_CON(x) (x * 0x4 + 0x44)
+#define RK2928_CLKGATE_CON(x) (x * 0x4 + 0xd0)
+#define RK2928_GLB_SRST_FST 0x100
+#define RK2928_GLB_SRST_SND 0x104
+#define RK2928_SOFTRST_CON(x) (x * 0x4 + 0x110)
+#define RK2928_MISC_CON 0x134
+
+#define PNAME(x) static const char *x[] __initconst
+
+enum rockchip_clk_branch_type {
+ branch_composite,
+ branch_mux,
+ branch_divider,
+ branch_fraction_divider,
+ branch_gate,
+};
+
+struct rockchip_clk_branch {
+ unsigned int id;
+ enum rockchip_clk_branch_type branch_type;
+ const char *name;
+ const char **parent_names;
+ u8 num_parents;
+ unsigned long flags;
+ int muxdiv_offset;
+ u8 mux_shift;
+ u8 mux_width;
+ u8 mux_flags;
+ u8 div_shift;
+ u8 div_width;
+ u8 div_flags;
+ struct clk_div_table *div_table;
+ int gate_offset;
+ u8 gate_shift;
+ u8 gate_flags;
+};
+
+#define COMPOSITE(_id, cname, pnames, f, mo, ms, mw, mf, ds, dw,\
+ df, go, gs, gf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_composite, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .mux_shift = ms, \
+ .mux_width = mw, \
+ .mux_flags = mf, \
+ .div_shift = ds, \
+ .div_width = dw, \
+ .div_flags = df, \
+ .gate_offset = go, \
+ .gate_shift = gs, \
+ .gate_flags = gf, \
+ }
+
+#define COMPOSITE_NOMUX(_id, cname, pname, f, mo, ds, dw, df, \
+ go, gs, gf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_composite, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .div_shift = ds, \
+ .div_width = dw, \
+ .div_flags = df, \
+ .gate_offset = go, \
+ .gate_shift = gs, \
+ .gate_flags = gf, \
+ }
+
+#define COMPOSITE_NOMUX_DIVTBL(_id, cname, pname, f, mo, ds, dw,\
+ df, dt, go, gs, gf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_composite, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .div_shift = ds, \
+ .div_width = dw, \
+ .div_flags = df, \
+ .div_table = dt, \
+ .gate_offset = go, \
+ .gate_shift = gs, \
+ .gate_flags = gf, \
+ }
+
+#define COMPOSITE_NODIV(_id, cname, pnames, f, mo, ms, mw, mf, \
+ go, gs, gf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_composite, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .mux_shift = ms, \
+ .mux_width = mw, \
+ .mux_flags = mf, \
+ .gate_offset = go, \
+ .gate_shift = gs, \
+ .gate_flags = gf, \
+ }
+
+#define COMPOSITE_NOGATE(_id, cname, pnames, f, mo, ms, mw, mf, \
+ ds, dw, df) \
+ { \
+ .id = _id, \
+ .branch_type = branch_composite, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .mux_shift = ms, \
+ .mux_width = mw, \
+ .mux_flags = mf, \
+ .div_shift = ds, \
+ .div_width = dw, \
+ .div_flags = df, \
+ .gate_offset = -1, \
+ }
+
+#define COMPOSITE_FRAC(_id, cname, pname, f, mo, df, go, gs, gf)\
+ { \
+ .id = _id, \
+ .branch_type = branch_fraction_divider, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .div_shift = 16, \
+ .div_width = 16, \
+ .div_flags = df, \
+ .gate_offset = go, \
+ .gate_shift = gs, \
+ .gate_flags = gf, \
+ }
+
+#define MUX(_id, cname, pnames, f, o, s, w, mf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_mux, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .muxdiv_offset = o, \
+ .mux_shift = s, \
+ .mux_width = w, \
+ .mux_flags = mf, \
+ .gate_offset = -1, \
+ }
+
+#define DIV(_id, cname, pname, f, o, s, w, df) \
+ { \
+ .id = _id, \
+ .branch_type = branch_divider, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .muxdiv_offset = o, \
+ .div_shift = s, \
+ .div_width = w, \
+ .div_flags = df, \
+ .gate_offset = -1, \
+ }
+
+#define DIVTBL(_id, cname, pname, f, o, s, w, df, dt) \
+ { \
+ .id = _id, \
+ .branch_type = branch_divider, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .muxdiv_offset = o, \
+ .div_shift = s, \
+ .div_width = w, \
+ .div_flags = df, \
+ .div_table = dt, \
+ }
+
+#define GATE(_id, cname, pname, f, o, b, gf) \
+ { \
+ .id = _id, \
+ .branch_type = branch_gate, \
+ .name = cname, \
+ .parent_names = (const char *[]){ pname }, \
+ .num_parents = 1, \
+ .flags = f, \
+ .gate_offset = o, \
+ .gate_shift = b, \
+ .gate_flags = gf, \
+ }
+
+
+void rockchip_clk_init(struct device_node *np, void __iomem *base,
+ unsigned long nr_clks);
+void rockchip_clk_add_lookup(struct clk *clk, unsigned int id);
+void rockchip_clk_register_branches(struct rockchip_clk_branch *clk_list,
+ unsigned int nr_clk);
+
+#endif
 
 

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