From bca9690b942654f668ffb5124b2bbd0ba0f007bb Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Mon, 19 Jan 2015 18:05:29 -0800 Subject: [PATCH] clk: divider: Make generic for usage elsewhere Some devices don't use mmio to interact with dividers. Split out the logic from the register read/write parts so that we can reuse the division logic elsewhere. Signed-off-by: Stephen Boyd Tested-by: Kenneth Westfield Signed-off-by: Michael Turquette --- drivers/clk/clk-divider.c | 216 +++++++++++++++++++++-------------- include/linux/clk-provider.h | 11 ++ 2 files changed, 141 insertions(+), 86 deletions(-) diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index c2bb9f679ec6..db7f8bce7467 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -30,7 +30,7 @@ #define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) -#define div_mask(d) ((1 << ((d)->width)) - 1) +#define div_mask(width) ((1 << (width)) - 1) static unsigned int _get_table_maxdiv(const struct clk_div_table *table) { @@ -54,15 +54,16 @@ static unsigned int _get_table_mindiv(const struct clk_div_table *table) return mindiv; } -static unsigned int _get_maxdiv(struct clk_divider *divider) +static unsigned int _get_maxdiv(const struct clk_div_table *table, u8 width, + unsigned long flags) { - if (divider->flags & CLK_DIVIDER_ONE_BASED) - return div_mask(divider); - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) - return 1 << div_mask(divider); - if (divider->table) - return _get_table_maxdiv(divider->table); - return div_mask(divider) + 1; + if (flags & CLK_DIVIDER_ONE_BASED) + return div_mask(width); + if (flags & CLK_DIVIDER_POWER_OF_TWO) + return 1 << div_mask(width); + if (table) + return _get_table_maxdiv(table); + return div_mask(width) + 1; } static unsigned int _get_table_div(const struct clk_div_table *table, @@ -76,14 +77,15 @@ static unsigned int _get_table_div(const struct clk_div_table *table, return 0; } -static unsigned int _get_div(struct clk_divider *divider, unsigned int val) +static unsigned int _get_div(const struct clk_div_table *table, + unsigned int val, unsigned long flags) { - if (divider->flags & CLK_DIVIDER_ONE_BASED) + if (flags & CLK_DIVIDER_ONE_BASED) return val; - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) + if (flags & CLK_DIVIDER_POWER_OF_TWO) return 1 << val; - if (divider->table) - return _get_table_div(divider->table, val); + if (table) + return _get_table_div(table, val); return val + 1; } @@ -98,29 +100,28 @@ static unsigned int _get_table_val(const struct clk_div_table *table, return 0; } -static unsigned int _get_val(struct clk_divider *divider, unsigned int div) +static unsigned int _get_val(const struct clk_div_table *table, + unsigned int div, unsigned long flags) { - if (divider->flags & CLK_DIVIDER_ONE_BASED) + if (flags & CLK_DIVIDER_ONE_BASED) return div; - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) + if (flags & CLK_DIVIDER_POWER_OF_TWO) return __ffs(div); - if (divider->table) - return _get_table_val(divider->table, div); + if (table) + return _get_table_val(table, div); return div - 1; } -static unsigned long clk_divider_recalc_rate(struct clk_hw *hw, - unsigned long parent_rate) +unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate, + unsigned int val, + const struct clk_div_table *table, + unsigned long flags) { - struct clk_divider *divider = to_clk_divider(hw); - unsigned int div, val; + unsigned int div; - val = clk_readl(divider->reg) >> divider->shift; - val &= div_mask(divider); - - div = _get_div(divider, val); + div = _get_div(table, val, flags); if (!div) { - WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO), + WARN(!(flags & CLK_DIVIDER_ALLOW_ZERO), "%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n", __clk_get_name(hw->clk)); return parent_rate; @@ -128,6 +129,20 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw, return DIV_ROUND_UP(parent_rate, div); } +EXPORT_SYMBOL_GPL(divider_recalc_rate); + +static unsigned long clk_divider_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_divider *divider = to_clk_divider(hw); + unsigned int val; + + val = clk_readl(divider->reg) >> divider->shift; + val &= div_mask(divider->width); + + return divider_recalc_rate(hw, parent_rate, val, divider->table, + divider->flags); +} /* * The reverse of DIV_ROUND_UP: The maximum number which @@ -146,12 +161,13 @@ static bool _is_valid_table_div(const struct clk_div_table *table, return false; } -static bool _is_valid_div(struct clk_divider *divider, unsigned int div) +static bool _is_valid_div(const struct clk_div_table *table, unsigned int div, + unsigned long flags) { - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) + if (flags & CLK_DIVIDER_POWER_OF_TWO) return is_power_of_2(div); - if (divider->table) - return _is_valid_table_div(divider->table, div); + if (table) + return _is_valid_table_div(table, div); return true; } @@ -191,71 +207,76 @@ static int _round_down_table(const struct clk_div_table *table, int div) return down; } -static int _div_round_up(struct clk_divider *divider, - unsigned long parent_rate, unsigned long rate) +static int _div_round_up(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate, + unsigned long flags) { int div = DIV_ROUND_UP(parent_rate, rate); - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) + if (flags & CLK_DIVIDER_POWER_OF_TWO) div = __roundup_pow_of_two(div); - if (divider->table) - div = _round_up_table(divider->table, div); + if (table) + div = _round_up_table(table, div); return div; } -static int _div_round_closest(struct clk_divider *divider, - unsigned long parent_rate, unsigned long rate) +static int _div_round_closest(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate, + unsigned long flags) { int up, down, div; up = down = div = DIV_ROUND_CLOSEST(parent_rate, rate); - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) { + if (flags & CLK_DIVIDER_POWER_OF_TWO) { up = __roundup_pow_of_two(div); down = __rounddown_pow_of_two(div); - } else if (divider->table) { - up = _round_up_table(divider->table, div); - down = _round_down_table(divider->table, div); + } else if (table) { + up = _round_up_table(table, div); + down = _round_down_table(table, div); } return (up - div) <= (div - down) ? up : down; } -static int _div_round(struct clk_divider *divider, unsigned long parent_rate, - unsigned long rate) +static int _div_round(const struct clk_div_table *table, + unsigned long parent_rate, unsigned long rate, + unsigned long flags) { - if (divider->flags & CLK_DIVIDER_ROUND_CLOSEST) - return _div_round_closest(divider, parent_rate, rate); + if (flags & CLK_DIVIDER_ROUND_CLOSEST) + return _div_round_closest(table, parent_rate, rate, flags); - return _div_round_up(divider, parent_rate, rate); + return _div_round_up(table, parent_rate, rate, flags); } -static bool _is_best_div(struct clk_divider *divider, - unsigned long rate, unsigned long now, unsigned long best) +static bool _is_best_div(unsigned long rate, unsigned long now, + unsigned long best, unsigned long flags) { - if (divider->flags & CLK_DIVIDER_ROUND_CLOSEST) + if (flags & CLK_DIVIDER_ROUND_CLOSEST) return abs(rate - now) < abs(rate - best); return now <= rate && now > best; } -static int _next_div(struct clk_divider *divider, int div) +static int _next_div(const struct clk_div_table *table, int div, + unsigned long flags) { div++; - if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) + if (flags & CLK_DIVIDER_POWER_OF_TWO) return __roundup_pow_of_two(div); - if (divider->table) - return _round_up_table(divider->table, div); + if (table) + return _round_up_table(table, div); return div; } static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, - unsigned long *best_parent_rate) + unsigned long *best_parent_rate, + const struct clk_div_table *table, u8 width, + unsigned long flags) { - struct clk_divider *divider = to_clk_divider(hw); int i, bestdiv = 0; unsigned long parent_rate, best = 0, now, maxdiv; unsigned long parent_rate_saved = *best_parent_rate; @@ -263,19 +284,11 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, if (!rate) rate = 1; - /* if read only, just return current value */ - if (divider->flags & CLK_DIVIDER_READ_ONLY) { - bestdiv = readl(divider->reg) >> divider->shift; - bestdiv &= div_mask(divider); - bestdiv = _get_div(divider, bestdiv); - return bestdiv; - } - - maxdiv = _get_maxdiv(divider); + maxdiv = _get_maxdiv(table, width, flags); if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) { parent_rate = *best_parent_rate; - bestdiv = _div_round(divider, parent_rate, rate); + bestdiv = _div_round(table, parent_rate, rate, flags); bestdiv = bestdiv == 0 ? 1 : bestdiv; bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv; return bestdiv; @@ -287,8 +300,8 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, */ maxdiv = min(ULONG_MAX / rate, maxdiv); - for (i = 1; i <= maxdiv; i = _next_div(divider, i)) { - if (!_is_valid_div(divider, i)) + for (i = 1; i <= maxdiv; i = _next_div(table, i, flags)) { + if (!_is_valid_div(table, i, flags)) continue; if (rate * i == parent_rate_saved) { /* @@ -302,7 +315,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), MULT_ROUND_UP(rate, i)); now = DIV_ROUND_UP(parent_rate, i); - if (_is_best_div(divider, rate, now, best)) { + if (_is_best_div(rate, now, best, flags)) { bestdiv = i; best = now; *best_parent_rate = parent_rate; @@ -310,48 +323,79 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, } if (!bestdiv) { - bestdiv = _get_maxdiv(divider); + bestdiv = _get_maxdiv(table, width, flags); *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1); } return bestdiv; } -static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, - unsigned long *prate) +long divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate, const struct clk_div_table *table, + u8 width, unsigned long flags) { int div; - div = clk_divider_bestdiv(hw, rate, prate); + + div = clk_divider_bestdiv(hw, rate, prate, table, width, flags); return DIV_ROUND_UP(*prate, div); } +EXPORT_SYMBOL_GPL(divider_round_rate); + +static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct clk_divider *divider = to_clk_divider(hw); + int bestdiv; + + /* if read only, just return current value */ + if (divider->flags & CLK_DIVIDER_READ_ONLY) { + bestdiv = readl(divider->reg) >> divider->shift; + bestdiv &= div_mask(divider->width); + bestdiv = _get_div(divider->table, bestdiv, divider->flags); + return bestdiv; + } + + return divider_round_rate(hw, rate, prate, divider->table, + divider->width, divider->flags); +} + +int divider_get_val(unsigned long rate, unsigned long parent_rate, + const struct clk_div_table *table, u8 width, + unsigned long flags) +{ + unsigned int div, value; + + div = DIV_ROUND_UP(parent_rate, rate); + + if (!_is_valid_div(table, div, flags)) + return -EINVAL; + + value = _get_val(table, div, flags); + + return min_t(unsigned int, value, div_mask(width)); +} +EXPORT_SYMBOL_GPL(divider_get_val); static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_divider *divider = to_clk_divider(hw); - unsigned int div, value; + unsigned int value; unsigned long flags = 0; u32 val; - div = DIV_ROUND_UP(parent_rate, rate); - - if (!_is_valid_div(divider, div)) - return -EINVAL; - - value = _get_val(divider, div); - - if (value > div_mask(divider)) - value = div_mask(divider); + value = divider_get_val(rate, parent_rate, divider->table, + divider->width, divider->flags); if (divider->lock) spin_lock_irqsave(divider->lock, flags); if (divider->flags & CLK_DIVIDER_HIWORD_MASK) { - val = div_mask(divider) << (divider->shift + 16); + val = div_mask(divider->width) << (divider->shift + 16); } else { val = clk_readl(divider->reg); - val &= ~(div_mask(divider) << divider->shift); + val &= ~(div_mask(divider->width) << divider->shift); } val |= value << divider->shift; clk_writel(val, divider->reg); diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index ba858e90d5de..0ed5bf2209ad 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -353,6 +353,17 @@ struct clk_divider { #define CLK_DIVIDER_READ_ONLY BIT(5) extern const struct clk_ops clk_divider_ops; + +unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate, + unsigned int val, const struct clk_div_table *table, + unsigned long flags); +long divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate, const struct clk_div_table *table, + u8 width, unsigned long flags); +int divider_get_val(unsigned long rate, unsigned long parent_rate, + const struct clk_div_table *table, u8 width, + unsigned long flags); + struct clk *clk_register_divider(struct device *dev, const char *name, const char *parent_name, unsigned long flags, void __iomem *reg, u8 shift, u8 width,