clk: rockchip: add basic infrastructure for clock branches
authorHeiko Stübner <heiko@sntech.de>
Wed, 2 Jul 2014 23:58:39 +0000 (01:58 +0200)
committerMike Turquette <mturquette@linaro.org>
Sun, 13 Jul 2014 19:17:06 +0000 (12:17 -0700)
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@sntech.de>
Acked-By: Max Schwarz <max.schwarz@online.de>
Tested-By: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
drivers/clk/rockchip/Makefile
drivers/clk/rockchip/clk.c [new file with mode: 0644]
drivers/clk/rockchip/clk.h [new file with mode: 0644]

index 8d3aefad2e73c4604c788f79749a5f64d9cc0eaf..0068a8b560b3261a43d0716333901f8f12cf0ca7 100644 (file)
@@ -3,3 +3,4 @@
 #
 
 obj-y  += clk-rockchip.o
+obj-y  += clk.o
diff --git a/drivers/clk/rockchip/clk.c b/drivers/clk/rockchip/clk.c
new file mode 100644 (file)
index 0000000..aa15d5a
--- /dev/null
@@ -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);
+       }
+}
diff --git a/drivers/clk/rockchip/clk.h b/drivers/clk/rockchip/clk.h
new file mode 100644 (file)
index 0000000..5b051b0
--- /dev/null
@@ -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