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 <sboyd@codeaurora.org>
Tested-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index c2bb9f679ec6c2ea4368a8df79aaa8d9da26972f..db7f8bce7467a2abfd37f6ccb8e22c784a6bce28 100644 (file)
--- 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 int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
-                               unsigned long parent_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;
-       unsigned long flags = 0;
-       u32 val;
 
        div = DIV_ROUND_UP(parent_rate, rate);
 
-       if (!_is_valid_div(divider, div))
+       if (!_is_valid_div(table, div, flags))
                return -EINVAL;
 
-       value = _get_val(divider, div);
+       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 value;
+       unsigned long flags = 0;
+       u32 val;
 
-       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 ba858e90d5de85a0411b4a21469aa4b07f7a2855..0ed5bf2209adf8122f05ceb9ef4ed8b099a07a9e 100644 (file)
--- 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,