[PATCH v2 5/9] clk: msm: Add support for root clock generators (RCGs)
Stephen Boyd
sboyd at codeaurora.org
Wed Oct 2 15:07:02 EDT 2013
Add support for the root clock generators on MSM devices. RCGs
are highly customizable mux/divider/counter clocks that can be
used to generate almost any rate desired given some input source
that is faster than the desired rate.
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
drivers/clk/msm/Makefile | 2 +
drivers/clk/msm/clk-rcg.c | 491 +++++++++++++++++++++++++++++++++++++++++++++
drivers/clk/msm/clk-rcg.h | 149 ++++++++++++++
drivers/clk/msm/clk-rcg2.c | 272 +++++++++++++++++++++++++
4 files changed, 914 insertions(+)
create mode 100644 drivers/clk/msm/clk-rcg.c
create mode 100644 drivers/clk/msm/clk-rcg.h
create mode 100644 drivers/clk/msm/clk-rcg2.c
diff --git a/drivers/clk/msm/Makefile b/drivers/clk/msm/Makefile
index 16b750f..fb78ac9 100644
--- a/drivers/clk/msm/Makefile
+++ b/drivers/clk/msm/Makefile
@@ -1,3 +1,5 @@
obj-$(CONFIG_COMMON_CLK_MSM) += clk-msm.o
clk-msm-$(CONFIG_COMMON_CLK_MSM) += clk-pll.o
+clk-msm-$(CONFIG_COMMON_CLK_MSM) += clk-rcg.o
+clk-msm-$(CONFIG_COMMON_CLK_MSM) += clk-rcg2.o
diff --git a/drivers/clk/msm/clk-rcg.c b/drivers/clk/msm/clk-rcg.c
new file mode 100644
index 0000000..15f52d5
--- /dev/null
+++ b/drivers/clk/msm/clk-rcg.c
@@ -0,0 +1,491 @@
+/*
+ * Copyright (c) 2013, The Linux Foundation. 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+
+#include <asm/div64.h>
+
+#include "clk-rcg.h"
+
+#define to_clk_rcg(_hw) container_of(_hw, struct clk_rcg, hw)
+
+#define to_clk_dyn_rcg(_hw) container_of(_hw, struct clk_dyn_rcg, hw)
+
+static u32 ns_to_src(struct src_sel *s, u32 ns)
+{
+ ns >>= s->src_sel_shift;
+ ns &= SRC_SEL_MASK;
+ return ns;
+}
+
+static u32 src_to_ns(struct src_sel *s, u8 src, u32 ns)
+{
+ u32 mask;
+
+ mask = SRC_SEL_MASK;
+ mask <<= s->src_sel_shift;
+ ns &= ~mask;
+
+ ns |= src << s->src_sel_shift;
+ return ns;
+}
+
+static u8 clk_rcg_get_parent(struct clk_hw *hw)
+{
+ struct clk_rcg *rcg = to_clk_rcg(hw);
+ int num_parents = __clk_get_num_parents(hw->clk);
+ u32 ns;
+ int i;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ ns = ns_to_src(&rcg->s, ns);
+ for (i = 0; i < num_parents; i++)
+ if (ns == rcg->s.parent_map[i])
+ return i;
+
+ return -EINVAL;
+}
+
+static int reg_to_bank(struct clk_dyn_rcg *rcg, u32 bank)
+{
+ bank &= BIT(rcg->mux_sel_bit);
+ return !!bank;
+}
+
+static u8 clk_dyn_rcg_get_parent(struct clk_hw *hw)
+{
+ struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
+ int num_parents = __clk_get_num_parents(hw->clk);
+ u32 ns, ctl;
+ int bank;
+ int i;
+ struct src_sel *s;
+
+ regmap_read(hw->regmap, hw->enable_reg, &ctl);
+ bank = reg_to_bank(rcg, ctl);
+ s = &rcg->s[bank];
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ ns = ns_to_src(s, ns);
+
+ for (i = 0; i < num_parents; i++)
+ if (ns == s->parent_map[i])
+ return i;
+
+ return -EINVAL;
+}
+
+static int clk_rcg_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_rcg *rcg = to_clk_rcg(hw);
+ u32 ns;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ ns = src_to_ns(&rcg->s, rcg->s.parent_map[index], ns);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ return 0;
+}
+
+static u32 md_to_m(struct mn *mn, u32 md)
+{
+ md >>= mn->m_val_shift;
+ md &= BIT(mn->width) - 1;
+ return md;
+}
+
+static u32 ns_to_pre_div(struct pre_div *p, u32 ns)
+{
+ ns >>= p->pre_div_shift;
+ ns &= BIT(p->pre_div_width) - 1;
+ return ns;
+}
+
+static u32 pre_div_to_ns(struct pre_div *p, u8 pre_div, u32 ns)
+{
+ u32 mask;
+
+ mask = BIT(p->pre_div_width) - 1;
+ mask <<= p->pre_div_shift;
+ ns &= ~mask;
+
+ ns |= pre_div << p->pre_div_shift;
+ return ns;
+}
+
+static u32 mn_to_md(struct mn *mn, u32 m, u32 n, u32 md)
+{
+ u32 mask, mask_w;
+
+ mask_w = BIT(mn->width) - 1;
+ mask = (mask_w << mn->m_val_shift) | mask_w;
+ md &= ~mask;
+
+ if (n) {
+ m <<= mn->m_val_shift;
+ md |= m;
+ md |= ~n & mask_w;
+ }
+
+ return md;
+}
+
+static u32 ns_m_to_n(struct mn *mn, u32 ns, u32 m)
+{
+ ns = ~ns >> mn->n_val_shift;
+ ns &= BIT(mn->width) - 1;
+ return ns + m;
+}
+
+static u32 reg_to_mnctr_mode(struct mn *mn, u32 val)
+{
+ val >>= mn->mnctr_mode_shift;
+ val &= MNCTR_MODE_MASK;
+ return val;
+}
+
+static u32 mn_to_ns(struct mn *mn, u32 m, u32 n, u32 ns)
+{
+ u32 mask;
+
+ mask = BIT(mn->width) - 1;
+ mask <<= mn->n_val_shift;
+ ns &= ~mask;
+
+ if (n) {
+ n = n - m;
+ n = ~n;
+ n &= BIT(mn->width) - 1;
+ n <<= mn->n_val_shift;
+ ns |= n;
+ }
+
+ return ns;
+}
+
+static u32 mn_to_reg(struct mn *mn, u32 m, u32 n, u32 val)
+{
+ u32 mask;
+
+ mask = MNCTR_MODE_MASK << mn->mnctr_mode_shift;
+ mask |= BIT(mn->mnctr_en_bit);
+ val &= ~mask;
+
+ if (n) {
+ val |= BIT(mn->mnctr_en_bit);
+ val |= MNCTR_MODE_DUAL << mn->mnctr_mode_shift;
+ }
+
+ return val;
+}
+
+static void configure_bank(struct clk_dyn_rcg *rcg, const struct freq_tbl *f)
+{
+ u32 ns, md, ctl, *regp;
+ int bank, new_bank;
+ struct mn *mn;
+ struct pre_div *p;
+ struct src_sel *s;
+ bool enabled;
+ u32 md_reg;
+ u32 bank_reg;
+ bool banked_mn = !!rcg->mn[1].width;
+ struct clk_hw *hw = &rcg->hw;
+
+ enabled = __clk_is_enabled(rcg->hw.clk);
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ regmap_read(hw->regmap, hw->enable_reg, &ctl);
+
+ if (banked_mn) {
+ regp = &ctl;
+ bank_reg = hw->enable_reg;
+ } else {
+ regp = &ns;
+ bank_reg = rcg->ns_reg;
+ }
+
+ bank = reg_to_bank(rcg, *regp);
+ new_bank = enabled ? !bank : bank;
+
+ if (banked_mn) {
+ mn = &rcg->mn[new_bank];
+ md_reg = rcg->md_reg[new_bank];
+
+ ns |= BIT(mn->mnctr_reset_bit);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ regmap_read(hw->regmap, md_reg, &md);
+ md = mn_to_md(mn, f->m, f->n, md);
+ regmap_write(hw->regmap, md_reg, md);
+
+ ns = mn_to_ns(mn, f->m, f->n, ns);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ ctl = mn_to_reg(mn, f->m, f->n, ctl);
+ regmap_write(hw->regmap, hw->enable_reg, ctl);
+
+ ns &= ~BIT(mn->mnctr_reset_bit);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+ } else {
+ p = &rcg->p[new_bank];
+ ns = pre_div_to_ns(p, f->pre_div - 1, ns);
+ }
+
+ s = &rcg->s[new_bank];
+ ns = src_to_ns(s, s->parent_map[f->src], ns);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ if (enabled) {
+ *regp ^= BIT(rcg->mux_sel_bit);
+ regmap_write(hw->regmap, bank_reg, *regp);
+ }
+}
+
+static int clk_dyn_rcg_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
+ u32 ns, ctl, md, reg;
+ int bank;
+ struct freq_tbl f = { 0 };
+ bool banked_mn = !!rcg->mn[1].width;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ regmap_read(hw->regmap, hw->enable_reg, &ctl);
+ reg = banked_mn ? ctl : ns;
+
+ bank = reg_to_bank(rcg, reg);
+
+ if (banked_mn) {
+ regmap_read(hw->regmap, rcg->md_reg[bank], &md);
+ f.m = md_to_m(&rcg->mn[bank], md);
+ f.n = ns_m_to_n(&rcg->mn[bank], ns, f.m);
+ } else {
+ f.pre_div = ns_to_pre_div(&rcg->p[bank], ns) + 1;
+ }
+ f.src = index;
+
+ configure_bank(rcg, &f);
+
+ return 0;
+}
+
+/*
+ * Calculate m/n:d rate
+ *
+ * parent_rate m
+ * rate = ----------- x ---
+ * pre_div n
+ */
+static unsigned long
+calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 pre_div)
+{
+ if (pre_div)
+ rate /= pre_div + 1;
+
+ if (mode) {
+ u64 tmp = rate;
+ tmp *= m;
+ do_div(tmp, n);
+ rate = tmp;
+ }
+
+ return rate;
+}
+
+static unsigned long
+clk_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct clk_rcg *rcg = to_clk_rcg(hw);
+ u32 pre_div, m, n, ns, md, mode;
+ struct mn *mn = &rcg->mn;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ regmap_read(hw->regmap, rcg->md_reg, &md);
+
+ pre_div = ns_to_pre_div(&rcg->p, ns);
+ m = md_to_m(mn, md);
+ n = ns_m_to_n(mn, ns, m);
+ /* MN counter mode is in hw.enable_reg sometimes */
+ if (hw->enable_reg != rcg->ns_reg)
+ regmap_read(hw->regmap, hw->enable_reg, &mode);
+ else
+ mode = ns;
+ mode = reg_to_mnctr_mode(mn, mode);
+
+ return calc_rate(parent_rate, m, n, mode, pre_div);
+}
+
+static unsigned long
+clk_dyn_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
+ u32 m, n, pre_div, ns, md, mode, reg;
+ int bank;
+ struct mn *mn;
+ bool banked_mn = !!rcg->mn[1].width;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+
+ if (banked_mn)
+ regmap_read(hw->regmap, hw->enable_reg, ®);
+ else
+ reg = ns;
+
+ bank = reg_to_bank(rcg, reg);
+
+ if (banked_mn) {
+ mn = &rcg->mn[bank];
+ regmap_read(hw->regmap, rcg->md_reg[bank], &md);
+ m = md_to_m(mn, md);
+ n = ns_m_to_n(mn, ns, m);
+ mode = reg_to_mnctr_mode(mn, reg);
+ return calc_rate(parent_rate, m, n, mode, 0);
+ } else {
+ pre_div = ns_to_pre_div(&rcg->p[bank], ns);
+ return calc_rate(parent_rate, 0, 0, 0, pre_div);
+ }
+}
+
+static const
+struct freq_tbl *find_freq(const struct freq_tbl *f, unsigned long rate)
+{
+ for (; f->freq; f++)
+ if (rate <= f->freq)
+ return f;
+
+ return NULL;
+}
+
+static long _freq_tbl_determine_rate(struct clk_hw *hw,
+ const struct freq_tbl *f, unsigned long rate,
+ unsigned long *p_rate, struct clk **p)
+{
+ f = find_freq(f, rate);
+ if (!f)
+ return -EINVAL;
+
+ *p = clk_get_parent_by_index(hw->clk, f->src);
+ *p_rate = __clk_get_rate(*p);
+
+ return f->freq;
+}
+
+static long clk_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *p_rate, struct clk **p)
+{
+ struct clk_rcg *rcg = to_clk_rcg(hw);
+
+ return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);
+}
+
+static long clk_dyn_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *p_rate, struct clk **p)
+{
+ struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
+
+ return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);
+}
+
+static int clk_rcg_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_rcg *rcg = to_clk_rcg(hw);
+ const struct freq_tbl *f;
+ u32 ns, md, ctl;
+ struct mn *mn = &rcg->mn;
+
+ f = find_freq(rcg->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ regmap_read(hw->regmap, rcg->ns_reg, &ns);
+ ns |= BIT(mn->mnctr_reset_bit);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ regmap_read(hw->regmap, rcg->md_reg, &md);
+ md = mn_to_md(mn, f->m, f->n, md);
+ regmap_write(hw->regmap, rcg->md_reg, md);
+
+ /* MN counter mode is in hw.enable_reg sometimes */
+ if (hw->enable_reg != rcg->ns_reg) {
+ regmap_read(hw->regmap, hw->enable_reg, &ctl);
+ ctl = mn_to_reg(mn, f->m, f->n, ctl);
+ regmap_write(hw->regmap, hw->enable_reg, ctl);
+ } else {
+ ns = mn_to_reg(mn, f->m, f->n, ns);
+ }
+ ns = mn_to_ns(mn, f->m, f->n, ns);
+ ns = pre_div_to_ns(&rcg->p, f->pre_div - 1, ns);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ ns &= ~BIT(mn->mnctr_reset_bit);
+ regmap_write(hw->regmap, rcg->ns_reg, ns);
+
+ return 0;
+}
+
+static int __clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate)
+{
+ struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);
+ const struct freq_tbl *f;
+
+ f = find_freq(rcg->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ configure_bank(rcg, f);
+
+ return 0;
+}
+
+static int clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ return __clk_dyn_rcg_set_rate(hw, rate);
+}
+
+static int clk_dyn_rcg_set_rate_and_parent(struct clk_hw *hw,
+ unsigned long rate, unsigned long parent_rate, u8 index)
+{
+ return __clk_dyn_rcg_set_rate(hw, rate);
+}
+
+const struct clk_ops clk_rcg_ops = {
+ .enable = clk_enable_regmap,
+ .disable = clk_disable_regmap,
+ .get_parent = clk_rcg_get_parent,
+ .set_parent = clk_rcg_set_parent,
+ .recalc_rate = clk_rcg_recalc_rate,
+ .determine_rate = clk_rcg_determine_rate,
+ .set_rate = clk_rcg_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_rcg_ops);
+
+const struct clk_ops clk_dyn_rcg_ops = {
+ .enable = clk_enable_regmap,
+ .is_enabled = clk_is_enabled_regmap,
+ .disable = clk_disable_regmap,
+ .get_parent = clk_dyn_rcg_get_parent,
+ .set_parent = clk_dyn_rcg_set_parent,
+ .recalc_rate = clk_dyn_rcg_recalc_rate,
+ .determine_rate = clk_dyn_rcg_determine_rate,
+ .set_rate = clk_dyn_rcg_set_rate,
+ .set_rate_and_parent = clk_dyn_rcg_set_rate_and_parent,
+};
+EXPORT_SYMBOL_GPL(clk_dyn_rcg_ops);
diff --git a/drivers/clk/msm/clk-rcg.h b/drivers/clk/msm/clk-rcg.h
new file mode 100644
index 0000000..2335176
--- /dev/null
+++ b/drivers/clk/msm/clk-rcg.h
@@ -0,0 +1,149 @@
+/*
+ * Copyright (c) 2013, The Linux Foundation. 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 __MSM_CLK_RCG_H__
+#define __MSM_CLK_RCG_H__
+
+#include <linux/clk-provider.h>
+
+struct freq_tbl {
+ unsigned long freq;
+ u8 src;
+ u8 pre_div;
+ u16 m;
+ u16 n;
+};
+
+/**
+ * struct mn - M/N:D counter
+ * @mnctr_en_bit: bit to enable mn counter
+ * @mnctr_reset_bit: bit to assert mn counter reset
+ * @mnctr_mode_shift: lowest bit of mn counter mode field
+ * @n_val_shift: lowest bit of n value field
+ * @m_val_shift: lowest bit of m value field
+ * @width: number of bits in m/n/d values
+ */
+struct mn {
+ u8 mnctr_en_bit;
+ u8 mnctr_reset_bit;
+ u8 mnctr_mode_shift;
+#define MNCTR_MODE_DUAL 0x2
+#define MNCTR_MODE_MASK 0x3
+ u8 n_val_shift;
+ u8 m_val_shift;
+ u8 width;
+};
+
+/**
+ * struct pre_div - pre-divider
+ * @pre_div_shift: lowest bit of pre divider field
+ * @pre_div_width: number of bits in predivider
+ */
+struct pre_div {
+ u8 pre_div_shift;
+ u8 pre_div_width;
+};
+
+/**
+ * struct src_sel - source selector
+ * @src_sel_shift: lowest bit of source selection field
+ * @parent_map: map from software's parent index to hardware's src_sel field
+ */
+struct src_sel {
+ u8 src_sel_shift;
+#define SRC_SEL_MASK 0x7
+ u8 *parent_map;
+};
+
+/**
+ * struct clk_rcg - root clock generator
+ *
+ * @ns_reg: NS register
+ * @md_reg: MD register
+ * @mn: mn counter
+ * @p: pre divider
+ * @s: source selector
+ * @freq_tbl: frequency table
+ * @hw: handle between common and hardware-specific interfaces
+ * @lock: register lock
+ *
+ */
+struct clk_rcg {
+ u32 ns_reg;
+ u32 md_reg;
+
+ struct mn mn;
+ struct pre_div p;
+ struct src_sel s;
+
+ const struct freq_tbl *freq_tbl;
+
+ struct clk_hw hw;
+};
+
+extern const struct clk_ops clk_rcg_ops;
+
+/**
+ * struct clk_dyn_rcg - root clock generator with glitch free mux
+ *
+ * @mux_sel_bit: bit to switch glitch free mux
+ * @ns_reg: NS register
+ * @md_reg: MD0 and MD1 register
+ * @mn: mn counter (banked)
+ * @s: source selector (banked)
+ * @freq_tbl: frequency table
+ * @hw: handle between common and hardware-specific interfaces
+ * @lock: register lock
+ *
+ */
+struct clk_dyn_rcg {
+ u32 ns_reg;
+ u32 md_reg[2];
+
+ u8 mux_sel_bit;
+
+ struct mn mn[2];
+ struct pre_div p[2];
+ struct src_sel s[2];
+
+ const struct freq_tbl *freq_tbl;
+
+ struct clk_hw hw;
+};
+
+extern const struct clk_ops clk_dyn_rcg_ops;
+
+/**
+ * struct clk_rcg2 - root clock generator
+ *
+ * @cmd_rcgr: corresponds to *_CMD_RCGR
+ * @mnd_width: number of bits in m/n/d values
+ * @hid_width: number of bits in half integer divider
+ * @parent_map: map from software's parent index to hardware's src_sel field
+ * @freq_tbl: frequency table
+ * @hw: handle between common and hardware-specific interfaces
+ * @lock: register lock
+ *
+ */
+struct clk_rcg2 {
+ u32 cmd_rcgr;
+ u8 mnd_width;
+ u8 hid_width;
+ u8 *parent_map;
+ const struct freq_tbl *freq_tbl;
+ struct clk_hw hw;
+};
+
+extern const struct clk_ops clk_rcg2_ops;
+
+#endif
diff --git a/drivers/clk/msm/clk-rcg2.c b/drivers/clk/msm/clk-rcg2.c
new file mode 100644
index 0000000..c970261
--- /dev/null
+++ b/drivers/clk/msm/clk-rcg2.c
@@ -0,0 +1,272 @@
+/*
+ * Copyright (c) 2013, The Linux Foundation. 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+
+#include <asm/div64.h>
+
+#include "clk-rcg.h"
+
+#define CMD_REG 0x0
+#define CMD_UPDATE BIT(0)
+#define CMD_ROOT_EN BIT(1)
+#define CMD_DIRTY_CFG BIT(4)
+#define CMD_DIRTY_N BIT(5)
+#define CMD_DIRTY_M BIT(6)
+#define CMD_DIRTY_D BIT(7)
+#define CMD_ROOT_OFF BIT(31)
+
+#define CFG_REG 0x4
+#define CFG_SRC_DIV_SHIFT 0
+#define CFG_SRC_SEL_SHIFT 8
+#define CFG_SRC_SEL_MASK (0x7 << CFG_SRC_SEL_SHIFT)
+#define CFG_MODE_SHIFT 12
+#define CFG_MODE_MASK (0x3 << CFG_MODE_SHIFT)
+#define CFG_MODE_DUAL_EDGE (0x2 << CFG_MODE_SHIFT)
+
+#define M_REG 0x8
+#define N_REG 0xc
+#define D_REG 0x10
+
+#define to_clk_rcg2(_hw) container_of(_hw, struct clk_rcg2, hw)
+
+static int clk_rcg2_is_enabled(struct clk_hw *hw)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+ u32 cmd;
+ int ret;
+
+ ret = regmap_read(hw->regmap, rcg->cmd_rcgr + CMD_REG, &cmd);
+ if (ret)
+ return ret;
+
+ return (cmd & CMD_ROOT_OFF) != 0;
+}
+
+static u8 clk_rcg2_get_parent(struct clk_hw *hw)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+ int num_parents = __clk_get_num_parents(hw->clk);
+ u32 cfg;
+ int i, ret;
+
+ ret = regmap_read(hw->regmap, rcg->cmd_rcgr + CFG_REG, &cfg);
+ if (ret)
+ return ret;
+
+ cfg &= CFG_SRC_SEL_MASK;
+ cfg >>= CFG_SRC_SEL_SHIFT;
+
+ for (i = 0; i < num_parents; i++)
+ if (cfg == rcg->parent_map[i])
+ return i;
+
+ return -EINVAL;
+}
+
+static int update_config(struct clk_rcg2 *rcg)
+{
+ int count, ret;
+ u32 cmd;
+ struct clk_hw *hw = &rcg->hw;
+ const char *name = __clk_get_name(hw->clk);
+
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + CMD_REG,
+ CMD_UPDATE, CMD_UPDATE);
+ if (ret)
+ return ret;
+
+ /* Wait for update to take effect */
+ for (count = 500; count > 0; count--) {
+ ret = regmap_read(hw->regmap, rcg->cmd_rcgr + CMD_REG, &cmd);
+ if (ret)
+ return ret;
+ if (!(cmd & CMD_UPDATE))
+ return 0;
+ udelay(1);
+ }
+
+ WARN(1, "%s: rcg didn't update its configuration.", name);
+ return 0;
+}
+
+static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+ int ret;
+
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + CFG_REG,
+ CFG_SRC_SEL_MASK,
+ rcg->parent_map[index] << CFG_SRC_SEL_SHIFT);
+ if (ret)
+ return ret;
+
+ return update_config(rcg);
+}
+
+/*
+ * Calculate m/n:d rate
+ *
+ * parent_rate m
+ * rate = ----------- x ---
+ * hid_div n
+ */
+static unsigned long
+calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 hid_div)
+{
+ if (hid_div) {
+ rate *= 2;
+ rate /= hid_div + 1;
+ }
+
+ if (mode) {
+ u64 tmp = rate;
+ tmp *= m;
+ do_div(tmp, n);
+ rate = tmp;
+ }
+
+ return rate;
+}
+
+static unsigned long
+clk_rcg2_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+ u32 cfg, hid_div, m = 0, n = 0, mode = 0, mask;
+
+ regmap_read(hw->regmap, rcg->cmd_rcgr + CFG_REG, &cfg);
+
+ if (rcg->mnd_width) {
+ mask = BIT(rcg->mnd_width) - 1;
+ regmap_read(hw->regmap, rcg->cmd_rcgr + M_REG, &m);
+ m &= mask;
+ regmap_read(hw->regmap, rcg->cmd_rcgr + N_REG, &n);
+ n = ~n;
+ n &= mask;
+ n += m;
+ mode = cfg & CFG_MODE_MASK;
+ mode >>= CFG_MODE_SHIFT;
+ }
+
+ mask = BIT(rcg->hid_width) - 1;
+ hid_div = cfg >> CFG_SRC_DIV_SHIFT;
+ hid_div &= mask;
+
+ return calc_rate(parent_rate, m, n, mode, hid_div);
+}
+
+static const
+struct freq_tbl *find_freq(const struct freq_tbl *f, unsigned long rate)
+{
+ for (; f->freq; f++)
+ if (rate <= f->freq)
+ return f;
+
+ return NULL;
+}
+
+static long _freq_tbl_determine_rate(struct clk_hw *hw,
+ const struct freq_tbl *f, unsigned long rate,
+ unsigned long *p_rate, struct clk **p)
+{
+ f = find_freq(f, rate);
+ if (!f)
+ return -EINVAL;
+
+ *p = clk_get_parent_by_index(hw->clk, f->src);
+ *p_rate = __clk_get_rate(*p);
+
+ return f->freq;
+}
+
+static long clk_rcg2_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *p_rate, struct clk **p)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+
+ return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);
+}
+
+static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate)
+{
+ struct clk_rcg2 *rcg = to_clk_rcg2(hw);
+ const struct freq_tbl *f;
+ u32 cfg, mask;
+ int ret;
+
+ f = find_freq(rcg->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ if (rcg->mnd_width && f->n) {
+ mask = BIT(rcg->mnd_width) - 1;
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + M_REG,
+ mask, f->m);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + N_REG,
+ mask, ~(f->n - f->m));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + D_REG,
+ mask, ~f->n);
+ if (ret)
+ return ret;
+ }
+
+ mask = BIT(rcg->hid_width) - 1;
+ mask |= CFG_SRC_SEL_MASK | CFG_MODE_MASK;
+ cfg = f->pre_div << CFG_SRC_DIV_SHIFT;
+ cfg |= rcg->parent_map[f->src] << CFG_SRC_SEL_SHIFT;
+ if (rcg->mnd_width && f->n)
+ cfg |= CFG_MODE_DUAL_EDGE;
+ ret = regmap_update_bits(hw->regmap, rcg->cmd_rcgr + CFG_REG, mask,
+ cfg);
+ if (ret)
+ return ret;
+
+ return update_config(rcg);
+}
+
+static int clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ return __clk_rcg2_set_rate(hw, rate);
+}
+
+static int clk_rcg2_set_rate_and_parent(struct clk_hw *hw,
+ unsigned long rate, unsigned long parent_rate, u8 index)
+{
+ return __clk_rcg2_set_rate(hw, rate);
+}
+
+const struct clk_ops clk_rcg2_ops = {
+ .is_enabled = clk_rcg2_is_enabled,
+ .get_parent = clk_rcg2_get_parent,
+ .set_parent = clk_rcg2_set_parent,
+ .recalc_rate = clk_rcg2_recalc_rate,
+ .determine_rate = clk_rcg2_determine_rate,
+ .set_rate = clk_rcg2_set_rate,
+ .set_rate_and_parent = clk_rcg2_set_rate_and_parent,
+};
+EXPORT_SYMBOL_GPL(clk_rcg2_ops);
--
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