1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sun6i-ar100.c b/drivers/clk/sunxi/clk-sun6i-ar100.c
new file mode 100644
index 000000000..9f9a2cf54
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun6i-ar100.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 Free Electrons
+ *
+ * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
+ *
+ * Allwinner A31 AR100 clock driver
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk-provider.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#include "clk-factors.h"
+
+/*
+ * sun6i_get_ar100_factors - Calculates factors p, m for AR100
+ *
+ * AR100 rate is calculated as follows
+ * rate = (parent_rate >> p) / (m + 1);
+ */
+static void sun6i_get_ar100_factors(struct factors_request *req)
+{
+	unsigned long div;
+	int shift;
+
+	/* clock only divides */
+	if (req->rate > req->parent_rate)
+		req->rate = req->parent_rate;
+
+	div = DIV_ROUND_UP(req->parent_rate, req->rate);
+
+	if (div < 32)
+		shift = 0;
+	else if (div >> 1 < 32)
+		shift = 1;
+	else if (div >> 2 < 32)
+		shift = 2;
+	else
+		shift = 3;
+
+	div >>= shift;
+
+	if (div > 32)
+		div = 32;
+
+	req->rate = (req->parent_rate >> shift) / div;
+	req->m = div - 1;
+	req->p = shift;
+}
+
+static const struct clk_factors_config sun6i_ar100_config = {
+	.mwidth = 5,
+	.mshift = 8,
+	.pwidth = 2,
+	.pshift = 4,
+};
+
+static const struct factors_data sun6i_ar100_data = {
+	.mux = 16,
+	.muxmask = GENMASK(1, 0),
+	.table = &sun6i_ar100_config,
+	.getter = sun6i_get_ar100_factors,
+};
+
+static DEFINE_SPINLOCK(sun6i_ar100_lock);
+
+static int sun6i_a31_ar100_clk_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	void __iomem *reg;
+	struct clk *clk;
+
+	reg = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	clk = sunxi_factors_register(np, &sun6i_ar100_data, &sun6i_ar100_lock,
+				     reg);
+	if (!clk)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, clk);
+
+	return 0;
+}
+
+static const struct of_device_id sun6i_a31_ar100_clk_dt_ids[] = {
+	{ .compatible = "allwinner,sun6i-a31-ar100-clk" },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver sun6i_a31_ar100_clk_driver = {
+	.driver = {
+		.name = "sun6i-a31-ar100-clk",
+		.of_match_table = sun6i_a31_ar100_clk_dt_ids,
+		.suppress_bind_attrs = true,
+	},
+	.probe = sun6i_a31_ar100_clk_probe,
+};
+builtin_platform_driver(sun6i_a31_ar100_clk_driver);