commit bca9690b942654f668ffb5124b2bbd0ba0f007bb Linux upstream adjusted
to current Barebox codebase.
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@xxxxxxxxxxxxxx>
Tested-by: Kenneth Westfield <kwestfie@xxxxxxxxxxxxxx>
Signed-off-by: Michael Turquette <mturquette@xxxxxxxxxx>
Signed-off-by: Marcin Niestroj <m.niestroj@xxxxxxxxxxxxxxxx>
---
drivers/clk/clk-divider.c | 116 +++++++++++++++++++++++---------------
include/linux/clk.h | 8 +++
2 files changed, 79 insertions(+), 45 deletions(-)
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index d705729af..566e6a5d0 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -22,7 +22,7 @@
#include <linux/log2.h>
#include <asm-generic/div64.h>
-#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)
{
@@ -35,15 +35,16 @@ static unsigned int _get_table_maxdiv(const struct clk_div_table *table)
return maxdiv;
}
-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,
@@ -79,14 +80,15 @@ 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;
}
@@ -109,7 +111,7 @@ static unsigned long clk_divider_recalc_rate(struct clk *clk,
unsigned int val;
val = readl(divider->reg) >> divider->shift;
- val &= div_mask(divider);
+ val &= div_mask(divider->width);
return divider_recalc_rate(clk, parent_rate, val, divider->table,
divider->flags, divider->width);
@@ -132,12 +134,13 @@ 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;
}
@@ -159,23 +162,25 @@ static int _round_up_table(const struct clk_div_table *table, int div)
return up;
}
-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 clk_divider_bestdiv(struct clk *clk, 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 = container_of(clk, struct clk_divider, clk);
int i, bestdiv = 0;
unsigned long parent_rate, best = 0, now, maxdiv;
unsigned long parent_rate_saved = *best_parent_rate;
@@ -183,11 +188,11 @@ static int clk_divider_bestdiv(struct clk *clk, unsigned long rate,
if (!rate)
rate = 1;
- maxdiv = _get_maxdiv(divider);
+ maxdiv = _get_maxdiv(table, width, flags);
if (!(clk->flags & CLK_SET_RATE_PARENT)) {
parent_rate = *best_parent_rate;
- bestdiv = _div_round_up(divider, parent_rate, rate);
+ bestdiv = _div_round_up(table, parent_rate, rate, flags);
bestdiv = bestdiv == 0 ? 1 : bestdiv;
bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
return bestdiv;
@@ -200,7 +205,7 @@ static int clk_divider_bestdiv(struct clk *clk, unsigned long rate,
maxdiv = min(ULONG_MAX / rate, maxdiv);
for (i = 1; i <= maxdiv; i++) {
- if (!_is_valid_div(divider, i))
+ if (!_is_valid_div(table, i, flags))
continue;
if (rate * i == parent_rate_saved) {
/*
@@ -222,25 +227,50 @@ static int clk_divider_bestdiv(struct clk *clk, unsigned long rate,
}
if (!bestdiv) {
- bestdiv = _get_maxdiv(divider);
+ bestdiv = _get_maxdiv(table, width, flags);
*best_parent_rate = clk_round_rate(clk_get_parent(clk), 1);
}
return bestdiv;
}
+long divider_round_rate(struct clk *clk, unsigned long rate,
+ unsigned long *prate, const struct clk_div_table *table,
+ u8 width, unsigned long flags)
+{
+ int div;
+
+ div = clk_divider_bestdiv(clk, rate, prate, table, width, flags);
+
+ return DIV_ROUND_UP(*prate, div);
+}
+
static long clk_divider_round_rate(struct clk *clk, unsigned long rate,
- unsigned long *parent_rate)
+ unsigned long *prate)
{
struct clk_divider *divider = container_of(clk, struct clk_divider, clk);
- int div;
if (divider->flags & CLK_DIVIDER_READ_ONLY)
- return clk_divider_recalc_rate(clk, *parent_rate);
+ return clk_divider_recalc_rate(clk, *prate);
+
+ return divider_round_rate(clk, 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;
- div = clk_divider_bestdiv(clk, rate, parent_rate);
+ value = _get_val(table, div, flags);
- return *parent_rate / div;
+ return min_t(unsigned int, value, div_mask(width));
}
static int clk_divider_set_rate(struct clk *clk, unsigned long rate,
@@ -255,26 +285,22 @@ static int clk_divider_set_rate(struct clk *clk, unsigned long rate,
if (clk->flags & CLK_SET_RATE_PARENT) {
unsigned long best_parent_rate = parent_rate;
- div = clk_divider_bestdiv(clk, rate, &best_parent_rate);
+ div = clk_divider_bestdiv(clk, rate, &best_parent_rate,
+ divider->table, divider->width, divider->flags);
clk_set_rate(clk_get_parent(clk), best_parent_rate);
} else {
div = DIV_ROUND_UP(parent_rate, rate);
}
- if (!_is_valid_div(divider->table, div, divider->flags))
- 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);
val = readl(divider->reg);
- val &= ~(div_mask(divider) << divider->shift);
+ val &= ~(div_mask(divider->width) << divider->shift);
val |= value << divider->shift;
if (clk->flags & CLK_DIVIDER_HIWORD_MASK)
- val |= div_mask(divider) << (divider->shift + 16);
+ val |= div_mask(divider->width) << (divider->shift + 16);
writel(val, divider->reg);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index b9c5e0ab0..ed78ffe46 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -354,6 +354,14 @@ unsigned long divider_recalc_rate(struct clk *clk, unsigned long parent_rate,
const struct clk_div_table *table,
unsigned long flags, unsigned long width);
+long divider_round_rate(struct clk *clk, 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_divider_alloc(const char *name, const char *parent,
unsigned clk_flags, void __iomem *reg,
u8 shift, u8 width, unsigned div_flags);
--
2.21.0
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