From 23b5e15a2994fb0c1444f92b76f09a482f32843c Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Sun, 29 Apr 2012 00:02:34 +0800 Subject: clk: mxs: add mxs specific clocks Add mxs specific clocks, pll, reference clock (PFD), integer divider and fractional divider. Signed-off-by: Shawn Guo diff --git a/drivers/clk/mxs/Makefile b/drivers/clk/mxs/Makefile new file mode 100644 index 0000000..d9472a8 --- /dev/null +++ b/drivers/clk/mxs/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for mxs specific clk +# + +obj-y += clk.o clk-pll.o clk-ref.o clk-div.o clk-frac.o diff --git a/drivers/clk/mxs/clk-div.c b/drivers/clk/mxs/clk-div.c new file mode 100644 index 0000000..90e1da9 --- /dev/null +++ b/drivers/clk/mxs/clk-div.c @@ -0,0 +1,110 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include +#include "clk.h" + +/** + * struct clk_div - mxs integer divider clock + * @divider: the parent class + * @ops: pointer to clk_ops of parent class + * @reg: register address + * @busy: busy bit shift + * + * The mxs divider clock is a subclass of basic clk_divider with an + * addtional busy bit. + */ +struct clk_div { + struct clk_divider divider; + const struct clk_ops *ops; + void __iomem *reg; + u8 busy; +}; + +static inline struct clk_div *to_clk_div(struct clk_hw *hw) +{ + struct clk_divider *divider = container_of(hw, struct clk_divider, hw); + + return container_of(divider, struct clk_div, divider); +} + +static unsigned long clk_div_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_div *div = to_clk_div(hw); + + return div->ops->recalc_rate(&div->divider.hw, parent_rate); +} + +static long clk_div_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_div *div = to_clk_div(hw); + + return div->ops->round_rate(&div->divider.hw, rate, prate); +} + +static int clk_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_div *div = to_clk_div(hw); + int ret; + + ret = div->ops->set_rate(&div->divider.hw, rate, parent_rate); + if (!ret) + ret = mxs_clk_wait(div->reg, div->busy); + + return ret; +} + +static struct clk_ops clk_div_ops = { + .recalc_rate = clk_div_recalc_rate, + .round_rate = clk_div_round_rate, + .set_rate = clk_div_set_rate, +}; + +struct clk *mxs_clk_div(const char *name, const char *parent_name, + void __iomem *reg, u8 shift, u8 width, u8 busy) +{ + struct clk_div *div; + struct clk *clk; + struct clk_init_data init; + + div = kzalloc(sizeof(*div), GFP_KERNEL); + if (!div) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_div_ops; + init.flags = CLK_SET_RATE_PARENT; + init.parent_names = (parent_name ? &parent_name: NULL); + init.num_parents = (parent_name ? 1 : 0); + + div->reg = reg; + div->busy = busy; + + div->divider.reg = reg; + div->divider.shift = shift; + div->divider.width = width; + div->divider.flags = CLK_DIVIDER_ONE_BASED; + div->divider.lock = &mxs_lock; + div->divider.hw.init = &init; + div->ops = &clk_divider_ops; + + clk = clk_register(NULL, &div->divider.hw); + if (IS_ERR(clk)) + kfree(div); + + return clk; +} diff --git a/drivers/clk/mxs/clk-frac.c b/drivers/clk/mxs/clk-frac.c new file mode 100644 index 0000000..e6aa6b5 --- /dev/null +++ b/drivers/clk/mxs/clk-frac.c @@ -0,0 +1,139 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include +#include +#include "clk.h" + +/** + * struct clk_frac - mxs fractional divider clock + * @hw: clk_hw for the fractional divider clock + * @reg: register address + * @shift: the divider bit shift + * @width: the divider bit width + * @busy: busy bit shift + * + * The clock is an adjustable fractional divider with a busy bit to wait + * when the divider is adjusted. + */ +struct clk_frac { + struct clk_hw hw; + void __iomem *reg; + u8 shift; + u8 width; + u8 busy; +}; + +#define to_clk_frac(_hw) container_of(_hw, struct clk_frac, hw) + +static unsigned long clk_frac_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_frac *frac = to_clk_frac(hw); + u32 div; + + div = readl_relaxed(frac->reg) >> frac->shift; + div &= (1 << frac->width) - 1; + + return (parent_rate >> frac->width) * div; +} + +static long clk_frac_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_frac *frac = to_clk_frac(hw); + unsigned long parent_rate = *prate; + u32 div; + u64 tmp; + + if (rate > parent_rate) + return -EINVAL; + + tmp = rate; + tmp <<= frac->width; + do_div(tmp, parent_rate); + div = tmp; + + if (!div) + return -EINVAL; + + return (parent_rate >> frac->width) * div; +} + +static int clk_frac_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_frac *frac = to_clk_frac(hw); + unsigned long flags; + u32 div, val; + u64 tmp; + + if (rate > parent_rate) + return -EINVAL; + + tmp = rate; + tmp <<= frac->width; + do_div(tmp, parent_rate); + div = tmp; + + if (!div) + return -EINVAL; + + spin_lock_irqsave(&mxs_lock, flags); + + val = readl_relaxed(frac->reg); + val &= ~(((1 << frac->width) - 1) << frac->shift); + val |= div << frac->shift; + writel_relaxed(val, frac->reg); + + spin_unlock_irqrestore(&mxs_lock, flags); + + return mxs_clk_wait(frac->reg, frac->busy); +} + +static struct clk_ops clk_frac_ops = { + .recalc_rate = clk_frac_recalc_rate, + .round_rate = clk_frac_round_rate, + .set_rate = clk_frac_set_rate, +}; + +struct clk *mxs_clk_frac(const char *name, const char *parent_name, + void __iomem *reg, u8 shift, u8 width, u8 busy) +{ + struct clk_frac *frac; + struct clk *clk; + struct clk_init_data init; + + frac = kzalloc(sizeof(*frac), GFP_KERNEL); + if (!frac) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_frac_ops; + init.flags = CLK_SET_RATE_PARENT; + init.parent_names = (parent_name ? &parent_name: NULL); + init.num_parents = (parent_name ? 1 : 0); + + frac->reg = reg; + frac->shift = shift; + frac->width = width; + frac->busy = busy; + frac->hw.init = &init; + + clk = clk_register(NULL, &frac->hw); + if (IS_ERR(clk)) + kfree(frac); + + return clk; +} diff --git a/drivers/clk/mxs/clk-pll.c b/drivers/clk/mxs/clk-pll.c new file mode 100644 index 0000000..fadae41 --- /dev/null +++ b/drivers/clk/mxs/clk-pll.c @@ -0,0 +1,116 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include +#include +#include +#include "clk.h" + +/** + * struct clk_pll - mxs pll clock + * @hw: clk_hw for the pll + * @base: base address of the pll + * @power: the shift of power bit + * @rate: the clock rate of the pll + * + * The mxs pll is a fixed rate clock with power and gate control, + * and the shift of gate bit is always 31. + */ +struct clk_pll { + struct clk_hw hw; + void __iomem *base; + u8 power; + unsigned long rate; +}; + +#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw) + +static int clk_pll_prepare(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << pll->power, pll->base + SET); + + udelay(10); + + return 0; +} + +static void clk_pll_unprepare(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << pll->power, pll->base + CLR); +} + +static int clk_pll_enable(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << 31, pll->base + CLR); + + return 0; +} + +static void clk_pll_disable(struct clk_hw *hw) +{ + struct clk_pll *pll = to_clk_pll(hw); + + writel_relaxed(1 << 31, pll->base + SET); +} + +static unsigned long clk_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pll *pll = to_clk_pll(hw); + + return pll->rate; +} + +static const struct clk_ops clk_pll_ops = { + .prepare = clk_pll_prepare, + .unprepare = clk_pll_unprepare, + .enable = clk_pll_enable, + .disable = clk_pll_disable, + .recalc_rate = clk_pll_recalc_rate, +}; + +struct clk *mxs_clk_pll(const char *name, const char *parent_name, + void __iomem *base, u8 power, unsigned long rate) +{ + struct clk_pll *pll; + struct clk *clk; + struct clk_init_data init; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_pll_ops; + init.flags = 0; + init.parent_names = (parent_name ? &parent_name: NULL); + init.num_parents = (parent_name ? 1 : 0); + + pll->base = base; + pll->rate = rate; + pll->power = power; + pll->hw.init = &init; + + clk = clk_register(NULL, &pll->hw); + if (IS_ERR(clk)) + kfree(pll); + + return clk; +} diff --git a/drivers/clk/mxs/clk-ref.c b/drivers/clk/mxs/clk-ref.c new file mode 100644 index 0000000..4adeed6 --- /dev/null +++ b/drivers/clk/mxs/clk-ref.c @@ -0,0 +1,154 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include +#include +#include "clk.h" + +/** + * struct clk_ref - mxs reference clock + * @hw: clk_hw for the reference clock + * @reg: register address + * @idx: the index of the reference clock within the same register + * + * The mxs reference clock sources from pll. Every 4 reference clocks share + * one register space, and @idx is used to identify them. Each reference + * clock has a gate control and a fractional * divider. The rate is calculated + * as pll rate * (18 / FRAC), where FRAC = 18 ~ 35. + */ +struct clk_ref { + struct clk_hw hw; + void __iomem *reg; + u8 idx; +}; + +#define to_clk_ref(_hw) container_of(_hw, struct clk_ref, hw) + +static int clk_ref_enable(struct clk_hw *hw) +{ + struct clk_ref *ref = to_clk_ref(hw); + + writel_relaxed(1 << ((ref->idx + 1) * 8 - 1), ref->reg + CLR); + + return 0; +} + +static void clk_ref_disable(struct clk_hw *hw) +{ + struct clk_ref *ref = to_clk_ref(hw); + + writel_relaxed(1 << ((ref->idx + 1) * 8 - 1), ref->reg + SET); +} + +static unsigned long clk_ref_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_ref *ref = to_clk_ref(hw); + u64 tmp = parent_rate; + u8 frac = (readl_relaxed(ref->reg) >> (ref->idx * 8)) & 0x3f; + + tmp *= 18; + do_div(tmp, frac); + + return tmp; +} + +static long clk_ref_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + unsigned long parent_rate = *prate; + u64 tmp = parent_rate; + u8 frac; + + tmp = tmp * 18 + rate / 2; + do_div(tmp, rate); + frac = tmp; + + if (frac < 18) + frac = 18; + else if (frac > 35) + frac = 35; + + tmp = parent_rate; + tmp *= 18; + do_div(tmp, frac); + + return tmp; +} + +static int clk_ref_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_ref *ref = to_clk_ref(hw); + unsigned long flags; + u64 tmp = parent_rate; + u32 val; + u8 frac, shift = ref->idx * 8; + + tmp = tmp * 18 + rate / 2; + do_div(tmp, rate); + frac = tmp; + + if (frac < 18) + frac = 18; + else if (frac > 35) + frac = 35; + + spin_lock_irqsave(&mxs_lock, flags); + + val = readl_relaxed(ref->reg); + val &= ~(0x3f << shift); + val |= frac << shift; + writel_relaxed(val, ref->reg); + + spin_unlock_irqrestore(&mxs_lock, flags); + + return 0; +} + +static const struct clk_ops clk_ref_ops = { + .enable = clk_ref_enable, + .disable = clk_ref_disable, + .recalc_rate = clk_ref_recalc_rate, + .round_rate = clk_ref_round_rate, + .set_rate = clk_ref_set_rate, +}; + +struct clk *mxs_clk_ref(const char *name, const char *parent_name, + void __iomem *reg, u8 idx) +{ + struct clk_ref *ref; + struct clk *clk; + struct clk_init_data init; + + ref = kzalloc(sizeof(*ref), GFP_KERNEL); + if (!ref) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_ref_ops; + init.flags = 0; + init.parent_names = (parent_name ? &parent_name: NULL); + init.num_parents = (parent_name ? 1 : 0); + + ref->reg = reg; + ref->idx = idx; + ref->hw.init = &init; + + clk = clk_register(NULL, &ref->hw); + if (IS_ERR(clk)) + kfree(ref); + + return clk; +} diff --git a/drivers/clk/mxs/clk.c b/drivers/clk/mxs/clk.c new file mode 100644 index 0000000..b24d560 --- /dev/null +++ b/drivers/clk/mxs/clk.c @@ -0,0 +1,28 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include + +DEFINE_SPINLOCK(mxs_lock); + +int mxs_clk_wait(void __iomem *reg, u8 shift) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(10); + + while (readl_relaxed(reg) & (1 << shift)) + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + + return 0; +} diff --git a/drivers/clk/mxs/clk.h b/drivers/clk/mxs/clk.h new file mode 100644 index 0000000..81421e2 --- /dev/null +++ b/drivers/clk/mxs/clk.h @@ -0,0 +1,66 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#ifndef __MXS_CLK_H +#define __MXS_CLK_H + +#include +#include +#include + +#define SET 0x4 +#define CLR 0x8 + +extern spinlock_t mxs_lock; + +int mxs_clk_wait(void __iomem *reg, u8 shift); + +struct clk *mxs_clk_pll(const char *name, const char *parent_name, + void __iomem *base, u8 power, unsigned long rate); + +struct clk *mxs_clk_ref(const char *name, const char *parent_name, + void __iomem *reg, u8 idx); + +struct clk *mxs_clk_div(const char *name, const char *parent_name, + void __iomem *reg, u8 shift, u8 width, u8 busy); + +struct clk *mxs_clk_frac(const char *name, const char *parent_name, + void __iomem *reg, u8 shift, u8 width, u8 busy); + +static inline struct clk *mxs_clk_fixed(const char *name, int rate) +{ + return clk_register_fixed_rate(NULL, name, NULL, CLK_IS_ROOT, rate); +} + +static inline struct clk *mxs_clk_gate(const char *name, + const char *parent_name, void __iomem *reg, u8 shift) +{ + return clk_register_gate(NULL, name, parent_name, CLK_SET_RATE_PARENT, + reg, shift, CLK_GATE_SET_TO_DISABLE, + &mxs_lock); +} + +static inline struct clk *mxs_clk_mux(const char *name, void __iomem *reg, + u8 shift, u8 width, const char **parent_names, int num_parents) +{ + return clk_register_mux(NULL, name, parent_names, num_parents, + CLK_SET_RATE_PARENT, reg, shift, width, + 0, &mxs_lock); +} + +static inline struct clk *mxs_clk_fixed_factor(const char *name, + const char *parent_name, unsigned int mult, unsigned int div) +{ + return clk_register_fixed_factor(NULL, name, parent_name, + CLK_SET_RATE_PARENT, mult, div); +} + +#endif /* __MXS_CLK_H */ -- cgit v0.10.2