clk: sunxi-ng: Add divider
Add support for the various dividers (linear, table or pow-of-two based)
found in the CCU.
Signed-off-by: Maxime Ripard <[email protected]>
Signed-off-by: Michael Turquette <[email protected]>
Link: lkml.kernel.org/r/[email protected]
diff --git a/drivers/clk/sunxi-ng/ccu_div.c b/drivers/clk/sunxi-ng/ccu_div.c
new file mode 100644
index 0000000..8659b4c
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_div.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <linux/clk-provider.h>
+
+#include "ccu_gate.h"
+#include "ccu_div.h"
+
+static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
+ unsigned long parent_rate,
+ unsigned long rate,
+ void *data)
+{
+ struct ccu_div *cd = data;
+ unsigned long val;
+
+ /*
+ * We can't use divider_round_rate that assumes that there's
+ * several parents, while we might be called to evaluate
+ * several different parents.
+ */
+ val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
+ cd->div.flags);
+
+ return divider_recalc_rate(&cd->common.hw, parent_rate, val,
+ cd->div.table, cd->div.flags);
+}
+
+static void ccu_div_disable(struct clk_hw *hw)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_gate_helper_disable(&cd->common, cd->enable);
+}
+
+static int ccu_div_enable(struct clk_hw *hw)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_gate_helper_enable(&cd->common, cd->enable);
+}
+
+static int ccu_div_is_enabled(struct clk_hw *hw)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
+}
+
+static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+ unsigned long val;
+ u32 reg;
+
+ reg = readl(cd->common.base + cd->common.reg);
+ val = reg >> cd->div.shift;
+ val &= (1 << cd->div.width) - 1;
+
+ ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
+ &parent_rate);
+
+ return divider_recalc_rate(hw, parent_rate, val, cd->div.table,
+ cd->div.flags);
+}
+
+static int ccu_div_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
+ req, ccu_div_round_rate, cd);
+}
+
+static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+ unsigned long flags;
+ unsigned long val;
+ u32 reg;
+
+ ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
+ &parent_rate);
+
+ val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
+ cd->div.flags);
+
+ spin_lock_irqsave(cd->common.lock, flags);
+
+ reg = readl(cd->common.base + cd->common.reg);
+ reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
+
+ writel(reg | (val << cd->div.shift),
+ cd->common.base + cd->common.reg);
+
+ spin_unlock_irqrestore(cd->common.lock, flags);
+
+ return 0;
+}
+
+static u8 ccu_div_get_parent(struct clk_hw *hw)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
+}
+
+static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct ccu_div *cd = hw_to_ccu_div(hw);
+
+ return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
+}
+
+const struct clk_ops ccu_div_ops = {
+ .disable = ccu_div_disable,
+ .enable = ccu_div_enable,
+ .is_enabled = ccu_div_is_enabled,
+
+ .get_parent = ccu_div_get_parent,
+ .set_parent = ccu_div_set_parent,
+
+ .determine_rate = ccu_div_determine_rate,
+ .recalc_rate = ccu_div_recalc_rate,
+ .set_rate = ccu_div_set_rate,
+};
