Linux-libre 4.5-gnu

1 files changed, 164 insertions, 33 deletions

diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c
index 08c5ee976..3bca438ec 100644
--- a/drivers/clk/versatile/clk-icst.c
+++ b/drivers/clk/versatile/clk-icst.c
@@ -3,7 +3,7 @@
  * We wrap the custom interface from <asm/hardware/icst.h> into the generic
  * clock framework.
  *
- * Copyright (C) 2012 Linus Walleij
+ * Copyright (C) 2012-2015 Linus Walleij
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -19,9 +19,14 @@
 #include <linux/err.h>
 #include <linux/clk-provider.h>
 #include <linux/io.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
 
 #include "clk-icst.h"
 
+/* Magic unlocking token used on all Versatile boards */
+#define VERSATILE_LOCK_VAL	0xA05F
+
 /**
  * struct clk_icst - ICST VCO clock wrapper
  * @hw: corresponding clock hardware entry
@@ -32,8 +37,9 @@
  */
 struct clk_icst {
 	struct clk_hw hw;
-	void __iomem *vcoreg;
-	void __iomem *lockreg;
+	struct regmap *map;
+	u32 vcoreg_off;
+	u32 lockreg_off;
 	struct icst_params *params;
 	unsigned long rate;
 };
@@ -41,53 +47,70 @@ struct clk_icst {
 #define to_icst(_hw) container_of(_hw, struct clk_icst, hw)
 
 /**
- * vco_get() - get ICST VCO settings from a certain register
- * @vcoreg: register containing the VCO settings
+ * vco_get() - get ICST VCO settings from a certain ICST
+ * @icst: the ICST clock to get
+ * @vco: the VCO struct to return the value in
  */
-static struct icst_vco vco_get(void __iomem *vcoreg)
+static int vco_get(struct clk_icst *icst, struct icst_vco *vco)
 {
 	u32 val;
-	struct icst_vco vco;
+	int ret;
 
-	val = readl(vcoreg);
-	vco.v = val & 0x1ff;
-	vco.r = (val >> 9) & 0x7f;
-	vco.s = (val >> 16) & 03;
-	return vco;
+	ret = regmap_read(icst->map, icst->vcoreg_off, &val);
+	if (ret)
+		return ret;
+	vco->v = val & 0x1ff;
+	vco->r = (val >> 9) & 0x7f;
+	vco->s = (val >> 16) & 03;
+	return 0;
 }
 
 /**
  * vco_set() - commit changes to an ICST VCO
- * @locreg: register to poke to unlock the VCO for writing
- * @vcoreg: register containing the VCO settings
- * @vco: ICST VCO parameters to commit
+ * @icst: the ICST clock to set
+ * @vco: the VCO struct to set the changes from
  */
-static void vco_set(void __iomem *lockreg,
-			void __iomem *vcoreg,
-			struct icst_vco vco)
+static int vco_set(struct clk_icst *icst, struct icst_vco vco)
 {
 	u32 val;
+	int ret;
 
-	val = readl(vcoreg) & ~0x7ffff;
+	ret = regmap_read(icst->map, icst->vcoreg_off, &val);
+	if (ret)
+		return ret;
+
+	/* Mask the 18 bits used by the VCO */
+	val &= ~0x7ffff;
 	val |= vco.v | (vco.r << 9) | (vco.s << 16);
 
 	/* This magic unlocks the VCO so it can be controlled */
-	writel(0xa05f, lockreg);
-	writel(val, vcoreg);
+	ret = regmap_write(icst->map, icst->lockreg_off, VERSATILE_LOCK_VAL);
+	if (ret)
+		return ret;
+	ret = regmap_write(icst->map, icst->vcoreg_off, val);
+	if (ret)
+		return ret;
 	/* This locks the VCO again */
-	writel(0, lockreg);
+	ret = regmap_write(icst->map, icst->lockreg_off, 0);
+	if (ret)
+		return ret;
+	return 0;
 }
 
-
 static unsigned long icst_recalc_rate(struct clk_hw *hw,
 				      unsigned long parent_rate)
 {
 	struct clk_icst *icst = to_icst(hw);
 	struct icst_vco vco;
+	int ret;
 
 	if (parent_rate)
 		icst->params->ref = parent_rate;
-	vco = vco_get(icst->vcoreg);
+	ret = vco_get(icst, &vco);
+	if (ret) {
+		pr_err("ICST: could not get VCO setting\n");
+		return 0;
+	}
 	icst->rate = icst_hz(icst->params, vco);
 	return icst->rate;
 }
@@ -112,8 +135,7 @@ static int icst_set_rate(struct clk_hw *hw, unsigned long rate,
 		icst->params->ref = parent_rate;
 	vco = icst_hz_to_vco(icst->params, rate);
 	icst->rate = icst_hz(icst->params, vco);
-	vco_set(icst->lockreg, icst->vcoreg, vco);
-	return 0;
+	return vco_set(icst, vco);
 }
 
 static const struct clk_ops icst_ops = {
@@ -122,11 +144,11 @@ static const struct clk_ops icst_ops = {
 	.set_rate = icst_set_rate,
 };
 
-struct clk *icst_clk_register(struct device *dev,
-			const struct clk_icst_desc *desc,
-			const char *name,
-			const char *parent_name,
-			void __iomem *base)
+static struct clk *icst_clk_setup(struct device *dev,
+				  const struct clk_icst_desc *desc,
+				  const char *name,
+				  const char *parent_name,
+				  struct regmap *map)
 {
 	struct clk *clk;
 	struct clk_icst *icst;
@@ -151,10 +173,11 @@ struct clk *icst_clk_register(struct device *dev,
 	init.flags = CLK_IS_ROOT;
 	init.parent_names = (parent_name ? &parent_name : NULL);
 	init.num_parents = (parent_name ? 1 : 0);
+	icst->map = map;
 	icst->hw.init = &init;
 	icst->params = pclone;
-	icst->vcoreg = base + desc->vco_offset;
-	icst->lockreg = base + desc->lock_offset;
+	icst->vcoreg_off = desc->vco_offset;
+	icst->lockreg_off = desc->lock_offset;
 
 	clk = clk_register(dev, &icst->hw);
 	if (IS_ERR(clk)) {
@@ -164,4 +187,112 @@ struct clk *icst_clk_register(struct device *dev,
 
 	return clk;
 }
+
+struct clk *icst_clk_register(struct device *dev,
+			const struct clk_icst_desc *desc,
+			const char *name,
+			const char *parent_name,
+			void __iomem *base)
+{
+	struct regmap_config icst_regmap_conf = {
+		.reg_bits = 32,
+		.val_bits = 32,
+		.reg_stride = 4,
+	};
+	struct regmap *map;
+
+	map = regmap_init_mmio(dev, base, &icst_regmap_conf);
+	if (IS_ERR(map)) {
+		pr_err("could not initialize ICST regmap\n");
+		return ERR_CAST(map);
+	}
+	return icst_clk_setup(dev, desc, name, parent_name, map);
+}
 EXPORT_SYMBOL_GPL(icst_clk_register);
+
+#ifdef CONFIG_OF
+/*
+ * In a device tree, an memory-mapped ICST clock appear as a child
+ * of a syscon node. Assume this and probe it only as a child of a
+ * syscon.
+ */
+
+static const struct icst_params icst525_params = {
+	.vco_max	= ICST525_VCO_MAX_5V,
+	.vco_min	= ICST525_VCO_MIN,
+	.vd_min		= 8,
+	.vd_max		= 263,
+	.rd_min		= 3,
+	.rd_max		= 65,
+	.s2div		= icst525_s2div,
+	.idx2s		= icst525_idx2s,
+};
+
+static const struct icst_params icst307_params = {
+	.vco_max	= ICST307_VCO_MAX,
+	.vco_min	= ICST307_VCO_MIN,
+	.vd_min		= 4 + 8,
+	.vd_max		= 511 + 8,
+	.rd_min		= 1 + 2,
+	.rd_max		= 127 + 2,
+	.s2div		= icst307_s2div,
+	.idx2s		= icst307_idx2s,
+};
+
+static void __init of_syscon_icst_setup(struct device_node *np)
+{
+	struct device_node *parent;
+	struct regmap *map;
+	struct clk_icst_desc icst_desc;
+	const char *name = np->name;
+	const char *parent_name;
+	struct clk *regclk;
+
+	/* We do not release this reference, we are using it perpetually */
+	parent = of_get_parent(np);
+	if (!parent) {
+		pr_err("no parent node for syscon ICST clock\n");
+		return;
+	}
+	map = syscon_node_to_regmap(parent);
+	if (IS_ERR(map)) {
+		pr_err("no regmap for syscon ICST clock parent\n");
+		return;
+	}
+
+	if (of_property_read_u32(np, "vco-offset", &icst_desc.vco_offset)) {
+		pr_err("no VCO register offset for ICST clock\n");
+		return;
+	}
+	if (of_property_read_u32(np, "lock-offset", &icst_desc.lock_offset)) {
+		pr_err("no lock register offset for ICST clock\n");
+		return;
+	}
+
+	if (of_device_is_compatible(np, "arm,syscon-icst525"))
+		icst_desc.params = &icst525_params;
+	else if (of_device_is_compatible(np, "arm,syscon-icst307"))
+		icst_desc.params = &icst307_params;
+	else {
+		pr_err("unknown ICST clock %s\n", name);
+		return;
+	}
+
+	/* Parent clock name is not the same as node parent */
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	regclk = icst_clk_setup(NULL, &icst_desc, name, parent_name, map);
+	if (IS_ERR(regclk)) {
+		pr_err("error setting up syscon ICST clock %s\n", name);
+		return;
+	}
+	of_clk_add_provider(np, of_clk_src_simple_get, regclk);
+	pr_debug("registered syscon ICST clock %s\n", name);
+}
+
+CLK_OF_DECLARE(arm_syscon_icst525_clk,
+	       "arm,syscon-icst525", of_syscon_icst_setup);
+CLK_OF_DECLARE(arm_syscon_icst307_clk,
+	       "arm,syscon-icst307", of_syscon_icst_setup);
+
+#endif