1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/clk/renesas/clk-rz.c b/drivers/clk/renesas/clk-rz.c
new file mode 100644
index 000000000..e770f09a2
--- /dev/null
+++ b/drivers/clk/renesas/clk-rz.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RZ/A1 Core CPG Clocks
+ *
+ * Copyright (C) 2013 Ideas On Board SPRL
+ * Copyright (C) 2014 Wolfram Sang, Sang Engineering <wsa@sang-engineering.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk/renesas.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+#define CPG_FRQCR	0x10
+#define CPG_FRQCR2	0x14
+
+#define PPR0		0xFCFE3200
+#define PIBC0		0xFCFE7000
+
+#define MD_CLK(x)	((x >> 2) & 1)	/* P0_2 */
+
+/* -----------------------------------------------------------------------------
+ * Initialization
+ */
+
+static u16 __init rz_cpg_read_mode_pins(void)
+{
+	void __iomem *ppr0, *pibc0;
+	u16 modes;
+
+	ppr0 = ioremap(PPR0, 2);
+	pibc0 = ioremap(PIBC0, 2);
+	BUG_ON(!ppr0 || !pibc0);
+	iowrite16(4, pibc0);	/* enable input buffer */
+	modes = ioread16(ppr0);
+	iounmap(ppr0);
+	iounmap(pibc0);
+
+	return modes;
+}
+
+static struct clk * __init
+rz_cpg_register_clock(struct device_node *np, void __iomem *base,
+		      const char *name)
+{
+	u32 val;
+	unsigned mult;
+	static const unsigned frqcr_tab[4] = { 3, 2, 0, 1 };
+
+	if (strcmp(name, "pll") == 0) {
+		unsigned int cpg_mode = MD_CLK(rz_cpg_read_mode_pins());
+		const char *parent_name = of_clk_get_parent_name(np, cpg_mode);
+
+		mult = cpg_mode ? (32 / 4) : 30;
+
+		return clk_register_fixed_factor(NULL, name, parent_name, 0, mult, 1);
+	}
+
+	/* If mapping regs failed, skip non-pll clocks. System will boot anyhow */
+	if (!base)
+		return ERR_PTR(-ENXIO);
+
+	/* FIXME:"i" and "g" are variable clocks with non-integer dividers (e.g. 2/3)
+	 * and the constraint that always g <= i. To get the rz platform started,
+	 * let them run at fixed current speed and implement the details later.
+	 */
+	if (strcmp(name, "i") == 0)
+		val = (readl(base + CPG_FRQCR) >> 8) & 3;
+	else if (strcmp(name, "g") == 0)
+		val = readl(base + CPG_FRQCR2) & 3;
+	else
+		return ERR_PTR(-EINVAL);
+
+	mult = frqcr_tab[val];
+	return clk_register_fixed_factor(NULL, name, "pll", 0, mult, 3);
+}
+
+static void __init rz_cpg_clocks_init(struct device_node *np)
+{
+	struct clk_onecell_data *data;
+	struct clk **clks;
+	void __iomem *base;
+	unsigned i;
+	int num_clks;
+
+	num_clks = of_property_count_strings(np, "clock-output-names");
+	if (WARN(num_clks <= 0, "can't count CPG clocks\n"))
+		return;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL);
+	BUG_ON(!data || !clks);
+
+	data->clks = clks;
+	data->clk_num = num_clks;
+
+	base = of_iomap(np, 0);
+
+	for (i = 0; i < num_clks; ++i) {
+		const char *name;
+		struct clk *clk;
+
+		of_property_read_string_index(np, "clock-output-names", i, &name);
+
+		clk = rz_cpg_register_clock(np, base, name);
+		if (IS_ERR(clk))
+			pr_err("%s: failed to register %pOFn %s clock (%ld)\n",
+			       __func__, np, name, PTR_ERR(clk));
+		else
+			data->clks[i] = clk;
+	}
+
+	of_clk_add_provider(np, of_clk_src_onecell_get, data);
+
+	cpg_mstp_add_clk_domain(np);
+}
+CLK_OF_DECLARE(rz_cpg_clks, "renesas,rz-cpg-clocks", rz_cpg_clocks_init);