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path: root/drivers/clk/sunxi-ng/ccu_frac.c
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-rw-r--r--drivers/clk/sunxi-ng/ccu_frac.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_frac.c b/drivers/clk/sunxi-ng/ccu_frac.c
new file mode 100644
index 000000000..44fcded8b
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_frac.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+
+#include "ccu_frac.h"
+
+bool ccu_frac_helper_is_enabled(struct ccu_common *common,
+ struct ccu_frac_internal *cf)
+{
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return false;
+
+ return !(readl(common->base + common->reg) & cf->enable);
+}
+
+void ccu_frac_helper_enable(struct ccu_common *common,
+ struct ccu_frac_internal *cf)
+{
+ unsigned long flags;
+ u32 reg;
+
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return;
+
+ spin_lock_irqsave(common->lock, flags);
+ reg = readl(common->base + common->reg);
+ writel(reg & ~cf->enable, common->base + common->reg);
+ spin_unlock_irqrestore(common->lock, flags);
+}
+
+void ccu_frac_helper_disable(struct ccu_common *common,
+ struct ccu_frac_internal *cf)
+{
+ unsigned long flags;
+ u32 reg;
+
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return;
+
+ spin_lock_irqsave(common->lock, flags);
+ reg = readl(common->base + common->reg);
+ writel(reg | cf->enable, common->base + common->reg);
+ spin_unlock_irqrestore(common->lock, flags);
+}
+
+bool ccu_frac_helper_has_rate(struct ccu_common *common,
+ struct ccu_frac_internal *cf,
+ unsigned long rate)
+{
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return false;
+
+ return (cf->rates[0] == rate) || (cf->rates[1] == rate);
+}
+
+unsigned long ccu_frac_helper_read_rate(struct ccu_common *common,
+ struct ccu_frac_internal *cf)
+{
+ u32 reg;
+
+ pr_debug("%s: Read fractional\n", clk_hw_get_name(&common->hw));
+
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return 0;
+
+ pr_debug("%s: clock is fractional (rates %lu and %lu)\n",
+ clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]);
+
+ reg = readl(common->base + common->reg);
+
+ pr_debug("%s: clock reg is 0x%x (select is 0x%x)\n",
+ clk_hw_get_name(&common->hw), reg, cf->select);
+
+ return (reg & cf->select) ? cf->rates[1] : cf->rates[0];
+}
+
+int ccu_frac_helper_set_rate(struct ccu_common *common,
+ struct ccu_frac_internal *cf,
+ unsigned long rate, u32 lock)
+{
+ unsigned long flags;
+ u32 reg, sel;
+
+ if (!(common->features & CCU_FEATURE_FRACTIONAL))
+ return -EINVAL;
+
+ if (cf->rates[0] == rate)
+ sel = 0;
+ else if (cf->rates[1] == rate)
+ sel = cf->select;
+ else
+ return -EINVAL;
+
+ spin_lock_irqsave(common->lock, flags);
+ reg = readl(common->base + common->reg);
+ reg &= ~cf->select;
+ writel(reg | sel, common->base + common->reg);
+ spin_unlock_irqrestore(common->lock, flags);
+
+ ccu_helper_wait_for_lock(common, lock);
+
+ return 0;
+}