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path: root/drivers/clk/qcom/clk-krait.c
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Diffstat (limited to 'drivers/clk/qcom/clk-krait.c')
-rw-r--r--drivers/clk/qcom/clk-krait.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/clk/qcom/clk-krait.c b/drivers/clk/qcom/clk-krait.c
new file mode 100644
index 000000000000..615bfbee1b6a
--- /dev/null
+++ b/drivers/clk/qcom/clk-krait.c
@@ -0,0 +1,166 @@
+/*
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/spinlock.h>
+
+#include <asm/krait-l2-accessors.h>
+
+#include "clk-krait.h"
+
+/* Secondary and primary muxes share the same cp15 register */
+static DEFINE_SPINLOCK(krait_clock_reg_lock);
+
+#define LPL_SHIFT 8
+static void __krait_mux_set_sel(struct krait_mux_clk *mux, int sel)
+{
+ unsigned long flags;
+ u32 regval;
+
+ spin_lock_irqsave(&krait_clock_reg_lock, flags);
+ regval = krait_get_l2_indirect_reg(mux->offset);
+ regval &= ~(mux->mask << mux->shift);
+ regval |= (sel & mux->mask) << mux->shift;
+ if (mux->lpl) {
+ regval &= ~(mux->mask << (mux->shift + LPL_SHIFT));
+ regval |= (sel & mux->mask) << (mux->shift + LPL_SHIFT);
+ }
+ krait_set_l2_indirect_reg(mux->offset, regval);
+ spin_unlock_irqrestore(&krait_clock_reg_lock, flags);
+
+ /* Wait for switch to complete. */
+ mb();
+ udelay(1);
+}
+
+static int krait_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct krait_mux_clk *mux = to_krait_mux_clk(hw);
+ u32 sel;
+
+ sel = clk_mux_reindex(index, mux->parent_map, 0);
+ mux->en_mask = sel;
+ /* Don't touch mux if CPU is off as it won't work */
+ if (__clk_is_enabled(hw->clk))
+ __krait_mux_set_sel(mux, sel);
+ return 0;
+}
+
+static u8 krait_mux_get_parent(struct clk_hw *hw)
+{
+ struct krait_mux_clk *mux = to_krait_mux_clk(hw);
+ u32 sel;
+
+ sel = krait_get_l2_indirect_reg(mux->offset);
+ sel >>= mux->shift;
+ sel &= mux->mask;
+ mux->en_mask = sel;
+
+ return clk_mux_get_parent(hw, sel, mux->parent_map, 0);
+}
+
+static struct clk *krait_mux_get_safe_parent(struct clk_hw *hw)
+{
+ int i;
+ struct krait_mux_clk *mux = to_krait_mux_clk(hw);
+ int num_parents = __clk_get_num_parents(hw->clk);
+
+ i = mux->safe_sel;
+ for (i = 0; i < num_parents; i++)
+ if (mux->safe_sel == mux->parent_map[i])
+ break;
+
+ return clk_get_parent_by_index(hw->clk, i);
+}
+
+static int krait_mux_enable(struct clk_hw *hw)
+{
+ struct krait_mux_clk *mux = to_krait_mux_clk(hw);
+
+ __krait_mux_set_sel(mux, mux->en_mask);
+
+ return 0;
+}
+
+static void krait_mux_disable(struct clk_hw *hw)
+{
+ struct krait_mux_clk *mux = to_krait_mux_clk(hw);
+
+ __krait_mux_set_sel(mux, mux->safe_sel);
+}
+
+const struct clk_ops krait_mux_clk_ops = {
+ .enable = krait_mux_enable,
+ .disable = krait_mux_disable,
+ .set_parent = krait_mux_set_parent,
+ .get_parent = krait_mux_get_parent,
+ .determine_rate = __clk_mux_determine_rate_closest,
+ .get_safe_parent = krait_mux_get_safe_parent,
+};
+EXPORT_SYMBOL_GPL(krait_mux_clk_ops);
+
+/* The divider can divide by 2, 4, 6 and 8. But we only really need div-2. */
+static long krait_div2_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ *parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), rate * 2);
+ return DIV_ROUND_UP(*parent_rate, 2);
+}
+
+static int krait_div2_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct krait_div2_clk *d = to_krait_div2_clk(hw);
+ unsigned long flags;
+ u32 val;
+ u32 mask = BIT(d->width) - 1;
+
+ if (d->lpl)
+ mask |= mask << (d->shift + LPL_SHIFT);
+
+ spin_lock_irqsave(&krait_clock_reg_lock, flags);
+ val = krait_get_l2_indirect_reg(d->offset);
+ val &= ~mask;
+ krait_set_l2_indirect_reg(d->offset, val);
+ spin_unlock_irqrestore(&krait_clock_reg_lock, flags);
+
+ return 0;
+}
+
+static unsigned long
+krait_div2_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct krait_div2_clk *d = to_krait_div2_clk(hw);
+ u32 mask = BIT(d->width) - 1;
+ u32 div;
+
+ div = krait_get_l2_indirect_reg(d->offset);
+ div >>= d->shift;
+ div &= mask;
+ div = (div + 1) * 2;
+
+ return DIV_ROUND_UP(parent_rate, div);
+}
+
+const struct clk_ops krait_div2_clk_ops = {
+ .round_rate = krait_div2_round_rate,
+ .set_rate = krait_div2_set_rate,
+ .recalc_rate = krait_div2_recalc_rate,
+};
+EXPORT_SYMBOL_GPL(krait_div2_clk_ops);