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path: root/drivers/clk/versatile/clk-sp810.c
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Diffstat (limited to 'drivers/clk/versatile/clk-sp810.c')
-rw-r--r--drivers/clk/versatile/clk-sp810.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/drivers/clk/versatile/clk-sp810.c b/drivers/clk/versatile/clk-sp810.c
new file mode 100644
index 000000000..caf0cd2fb
--- /dev/null
+++ b/drivers/clk/versatile/clk-sp810.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Copyright (C) 2013 ARM Limited
+ */
+
+#include <linux/amba/sp810.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#define to_clk_sp810_timerclken(_hw) \
+ container_of(_hw, struct clk_sp810_timerclken, hw)
+
+struct clk_sp810;
+
+struct clk_sp810_timerclken {
+ struct clk_hw hw;
+ struct clk *clk;
+ struct clk_sp810 *sp810;
+ int channel;
+};
+
+struct clk_sp810 {
+ struct device_node *node;
+ void __iomem *base;
+ spinlock_t lock;
+ struct clk_sp810_timerclken timerclken[4];
+};
+
+static u8 clk_sp810_timerclken_get_parent(struct clk_hw *hw)
+{
+ struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+ u32 val = readl(timerclken->sp810->base + SCCTRL);
+
+ return !!(val & (1 << SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel)));
+}
+
+static int clk_sp810_timerclken_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+ struct clk_sp810 *sp810 = timerclken->sp810;
+ u32 val, shift = SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel);
+ unsigned long flags = 0;
+
+ if (WARN_ON(index > 1))
+ return -EINVAL;
+
+ spin_lock_irqsave(&sp810->lock, flags);
+
+ val = readl(sp810->base + SCCTRL);
+ val &= ~(1 << shift);
+ val |= index << shift;
+ writel(val, sp810->base + SCCTRL);
+
+ spin_unlock_irqrestore(&sp810->lock, flags);
+
+ return 0;
+}
+
+static const struct clk_ops clk_sp810_timerclken_ops = {
+ .get_parent = clk_sp810_timerclken_get_parent,
+ .set_parent = clk_sp810_timerclken_set_parent,
+};
+
+static struct clk *clk_sp810_timerclken_of_get(struct of_phandle_args *clkspec,
+ void *data)
+{
+ struct clk_sp810 *sp810 = data;
+
+ if (WARN_ON(clkspec->args_count != 1 ||
+ clkspec->args[0] >= ARRAY_SIZE(sp810->timerclken)))
+ return NULL;
+
+ return sp810->timerclken[clkspec->args[0]].clk;
+}
+
+static void __init clk_sp810_of_setup(struct device_node *node)
+{
+ struct clk_sp810 *sp810 = kzalloc(sizeof(*sp810), GFP_KERNEL);
+ const char *parent_names[2];
+ int num = ARRAY_SIZE(parent_names);
+ char name[12];
+ struct clk_init_data init;
+ static int instance;
+ int i;
+ bool deprecated;
+
+ if (!sp810)
+ return;
+
+ if (of_clk_parent_fill(node, parent_names, num) != num) {
+ pr_warn("Failed to obtain parent clocks for SP810!\n");
+ kfree(sp810);
+ return;
+ }
+
+ sp810->node = node;
+ sp810->base = of_iomap(node, 0);
+ spin_lock_init(&sp810->lock);
+
+ init.name = name;
+ init.ops = &clk_sp810_timerclken_ops;
+ init.flags = 0;
+ init.parent_names = parent_names;
+ init.num_parents = num;
+
+ deprecated = !of_find_property(node, "assigned-clock-parents", NULL);
+
+ for (i = 0; i < ARRAY_SIZE(sp810->timerclken); i++) {
+ snprintf(name, sizeof(name), "sp810_%d_%d", instance, i);
+
+ sp810->timerclken[i].sp810 = sp810;
+ sp810->timerclken[i].channel = i;
+ sp810->timerclken[i].hw.init = &init;
+
+ /*
+ * If DT isn't setting the parent, force it to be
+ * the 1 MHz clock without going through the framework.
+ * We do this before clk_register() so that it can determine
+ * the parent and setup the tree properly.
+ */
+ if (deprecated)
+ init.ops->set_parent(&sp810->timerclken[i].hw, 1);
+
+ sp810->timerclken[i].clk = clk_register(NULL,
+ &sp810->timerclken[i].hw);
+ WARN_ON(IS_ERR(sp810->timerclken[i].clk));
+ }
+
+ of_clk_add_provider(node, clk_sp810_timerclken_of_get, sp810);
+ instance++;
+}
+CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup);