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path: root/drivers/clk/mvebu/armada-37xx-periph.c
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Diffstat (limited to 'drivers/clk/mvebu/armada-37xx-periph.c')
-rw-r--r--drivers/clk/mvebu/armada-37xx-periph.c130
1 files changed, 129 insertions, 1 deletions
diff --git a/drivers/clk/mvebu/armada-37xx-periph.c b/drivers/clk/mvebu/armada-37xx-periph.c
index 902a6cc..b1a3596 100644
--- a/drivers/clk/mvebu/armada-37xx-periph.c
+++ b/drivers/clk/mvebu/armada-37xx-periph.c
@@ -224,11 +224,21 @@ static const struct clk_periph clks_sb[] = {
{ },
};
-static inline int get_mux(struct a37xx_periphclk *priv, int shift)
+static int get_mux(struct a37xx_periphclk *priv, int shift)
{
return (readl(priv->reg + TBG_SEL) >> shift) & 3;
}
+static void set_mux(struct a37xx_periphclk *priv, int shift, int val)
+{
+ u32 reg;
+
+ reg = readl(priv->reg + TBG_SEL);
+ reg &= ~(3 << shift);
+ reg |= (val & 3) << shift;
+ writel(reg, priv->reg + TBG_SEL);
+}
+
static ulong periph_clk_get_rate(struct a37xx_periphclk *priv, int id);
static ulong get_parent_rate(struct a37xx_periphclk *priv, int id)
@@ -277,6 +287,17 @@ static ulong get_div(struct a37xx_periphclk *priv,
return 0;
}
+static void set_div_val(struct a37xx_periphclk *priv,
+ const struct clk_periph *clk, int idx, int val)
+{
+ u32 reg;
+
+ reg = readl(priv->reg + clk->div_reg_off[idx]);
+ reg &= ~(clk->div_mask[idx] << clk->div_shift[idx]);
+ reg |= (val & clk->div_mask[idx]) << clk->div_shift[idx];
+ writel(reg, priv->reg + clk->div_reg_off[idx]);
+}
+
static ulong periph_clk_get_rate(struct a37xx_periphclk *priv, int id)
{
const struct clk_periph *clk = &priv->clks[id];
@@ -337,6 +358,111 @@ static int armada_37xx_periph_clk_disable(struct clk *clk)
return periph_clk_enable(clk, 0);
}
+#define diff(a, b) abs((long)(a) - (long)(b))
+
+static ulong find_best_div(const struct clk_div_table *t0,
+ const struct clk_div_table *t1, ulong parent_rate,
+ ulong req_rate, int *v0, int *v1)
+{
+ const struct clk_div_table *i, *j;
+ ulong rate, best_rate = 0;
+
+ for (i = t0; i && i->div; ++i) {
+ for (j = t1; j && j->div; ++j) {
+ rate = DIV_ROUND_UP(parent_rate, i->div * j->div);
+
+ if (!best_rate ||
+ diff(rate, req_rate) < diff(best_rate, req_rate)) {
+ best_rate = rate;
+ *v0 = i->val;
+ *v1 = j->val;
+ }
+ }
+ }
+
+ return best_rate;
+}
+
+static ulong armada_37xx_periph_clk_set_rate(struct clk *clk, ulong req_rate)
+{
+ struct a37xx_periphclk *priv = dev_get_priv(clk->dev);
+ const struct clk_periph *periph_clk = &priv->clks[clk->id];
+ ulong rate, old_rate, parent_rate;
+ int div_val0 = 0, div_val1 = 0;
+ const struct clk_div_table *t1;
+ static const struct clk_div_table empty_table[2] = {
+ { 1, 0 },
+ { 0, 0 }
+ };
+
+ if (clk->id > priv->count)
+ return -EINVAL;
+
+ old_rate = periph_clk_get_rate(priv, clk->id);
+ if (old_rate == -EINVAL)
+ return -EINVAL;
+
+ if (old_rate == req_rate)
+ return old_rate;
+
+ if (!periph_clk->can_gate || !periph_clk->dividers)
+ return -ENOTSUPP;
+
+ parent_rate = get_parent_rate(priv, clk->id);
+ if (parent_rate == -EINVAL)
+ return -EINVAL;
+
+ t1 = empty_table;
+ if (periph_clk->dividers > 1)
+ t1 = periph_clk->div_table[1];
+
+ rate = find_best_div(periph_clk->div_table[0], t1, parent_rate,
+ req_rate, &div_val0, &div_val1);
+
+ periph_clk_enable(clk, 0);
+
+ set_div_val(priv, periph_clk, 0, div_val0);
+ if (periph_clk->dividers > 1)
+ set_div_val(priv, periph_clk, 1, div_val1);
+
+ periph_clk_enable(clk, 1);
+
+ return rate;
+}
+
+static int armada_37xx_periph_clk_set_parent(struct clk *clk,
+ struct clk *parent)
+{
+ struct a37xx_periphclk *priv = dev_get_priv(clk->dev);
+ const struct clk_periph *periph_clk = &priv->clks[clk->id];
+ struct clk check_parent;
+ int ret;
+
+ /* We also check if parent is our TBG clock */
+ if (clk->id > priv->count || parent->id >= MAX_TBG_PARENTS)
+ return -EINVAL;
+
+ if (!periph_clk->can_mux || !periph_clk->can_gate)
+ return -ENOTSUPP;
+
+ ret = clk_get_by_index(clk->dev, 0, &check_parent);
+ if (ret < 0)
+ return ret;
+
+ if (parent->dev != check_parent.dev)
+ ret = -EINVAL;
+
+ clk_free(&check_parent);
+ if (ret < 0)
+ return ret;
+
+ periph_clk_enable(clk, 0);
+ set_mux(priv, periph_clk->mux_shift, parent->id);
+ periph_clk_enable(clk, 1);
+
+ return 0;
+}
+
#if defined(CONFIG_CMD_CLK) && defined(CONFIG_CLK_ARMADA_3720)
static int armada_37xx_periph_clk_dump(struct udevice *dev)
{
@@ -473,6 +599,8 @@ static int armada_37xx_periph_clk_probe(struct udevice *dev)
static const struct clk_ops armada_37xx_periph_clk_ops = {
.get_rate = armada_37xx_periph_clk_get_rate,
+ .set_rate = armada_37xx_periph_clk_set_rate,
+ .set_parent = armada_37xx_periph_clk_set_parent,
.enable = armada_37xx_periph_clk_enable,
.disable = armada_37xx_periph_clk_disable,
};