Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

9 files changed, 911 insertions, 0 deletions

diff --git a/kernel/drivers/clk/versatile/Kconfig b/kernel/drivers/clk/versatile/Kconfig
new file mode 100644
index 000000000..1530c9352
--- /dev/null
+++ b/kernel/drivers/clk/versatile/Kconfig
@@ -0,0 +1,26 @@
+config COMMON_CLK_VERSATILE
+	bool "Clock driver for ARM Reference designs"
+	depends on ARCH_INTEGRATOR || ARCH_REALVIEW || ARCH_VEXPRESS || ARM64
+	---help---
+          Supports clocking on ARM Reference designs:
+	  - Integrator/AP and Integrator/CP
+	  - RealView PB1176, EB, PB11MP and PBX
+	  - Versatile Express
+
+config CLK_SP810
+	bool "Clock driver for ARM SP810 System Controller"
+	depends on COMMON_CLK_VERSATILE
+	default y if ARCH_VEXPRESS
+	---help---
+	  Supports clock muxing (REFCLK/TIMCLK to TIMERCLKEN0-3) capabilities
+	  of the ARM SP810 System Controller cell.
+
+config CLK_VEXPRESS_OSC
+	bool "Clock driver for Versatile Express OSC clock generators"
+	depends on COMMON_CLK_VERSATILE
+	depends on VEXPRESS_CONFIG
+	default y if ARCH_VEXPRESS
+	---help---
+	  Simple regmap-based driver driving clock generators on Versatile
+	  Express platforms hidden behind its configuration infrastructure,
+	  commonly known as OSCs.
diff --git a/kernel/drivers/clk/versatile/Makefile b/kernel/drivers/clk/versatile/Makefile
new file mode 100644
index 000000000..8ff03744f
--- /dev/null
+++ b/kernel/drivers/clk/versatile/Makefile
@@ -0,0 +1,6 @@
+# Makefile for Versatile-specific clocks
+obj-$(CONFIG_ICST)		+= clk-icst.o clk-versatile.o
+obj-$(CONFIG_INTEGRATOR_IMPD1)	+= clk-impd1.o
+obj-$(CONFIG_ARCH_REALVIEW)	+= clk-realview.o
+obj-$(CONFIG_CLK_SP810)		+= clk-sp810.o
+obj-$(CONFIG_CLK_VEXPRESS_OSC)	+= clk-vexpress-osc.o
diff --git a/kernel/drivers/clk/versatile/clk-icst.c b/kernel/drivers/clk/versatile/clk-icst.c
new file mode 100644
index 000000000..bc96f103b
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-icst.c
@@ -0,0 +1,164 @@
+/*
+ * Driver for the ICST307 VCO clock found in the ARM Reference designs.
+ * We wrap the custom interface from <asm/hardware/icst.h> into the generic
+ * clock framework.
+ *
+ * Copyright (C) 2012 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
+ * published by the Free Software Foundation.
+ *
+ * TODO: when all ARM reference designs are migrated to generic clocks, the
+ * ICST clock code from the ARM tree should probably be merged into this
+ * file.
+ */
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+
+#include "clk-icst.h"
+
+/**
+ * struct clk_icst - ICST VCO clock wrapper
+ * @hw: corresponding clock hardware entry
+ * @vcoreg: VCO register address
+ * @lockreg: VCO lock register address
+ * @params: parameters for this ICST instance
+ * @rate: current rate
+ */
+struct clk_icst {
+	struct clk_hw hw;
+	void __iomem *vcoreg;
+	void __iomem *lockreg;
+	struct icst_params *params;
+	unsigned long rate;
+};
+
+#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
+ */
+static struct icst_vco vco_get(void __iomem *vcoreg)
+{
+	u32 val;
+	struct icst_vco vco;
+
+	val = readl(vcoreg);
+	vco.v = val & 0x1ff;
+	vco.r = (val >> 9) & 0x7f;
+	vco.s = (val >> 16) & 03;
+	return vco;
+}
+
+/**
+ * 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
+ */
+static void vco_set(void __iomem *lockreg,
+			void __iomem *vcoreg,
+			struct icst_vco vco)
+{
+	u32 val;
+
+	val = readl(vcoreg) & ~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);
+	/* This locks the VCO again */
+	writel(0, lockreg);
+}
+
+
+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;
+
+	if (parent_rate)
+		icst->params->ref = parent_rate;
+	vco = vco_get(icst->vcoreg);
+	icst->rate = icst_hz(icst->params, vco);
+	return icst->rate;
+}
+
+static long icst_round_rate(struct clk_hw *hw, unsigned long rate,
+			    unsigned long *prate)
+{
+	struct clk_icst *icst = to_icst(hw);
+	struct icst_vco vco;
+
+	vco = icst_hz_to_vco(icst->params, rate);
+	return icst_hz(icst->params, vco);
+}
+
+static int icst_set_rate(struct clk_hw *hw, unsigned long rate,
+			 unsigned long parent_rate)
+{
+	struct clk_icst *icst = to_icst(hw);
+	struct icst_vco vco;
+
+	if (parent_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;
+}
+
+static const struct clk_ops icst_ops = {
+	.recalc_rate = icst_recalc_rate,
+	.round_rate = icst_round_rate,
+	.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)
+{
+	struct clk *clk;
+	struct clk_icst *icst;
+	struct clk_init_data init;
+	struct icst_params *pclone;
+
+	icst = kzalloc(sizeof(struct clk_icst), GFP_KERNEL);
+	if (!icst) {
+		pr_err("could not allocate ICST clock!\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	pclone = kmemdup(desc->params, sizeof(*pclone), GFP_KERNEL);
+	if (!pclone) {
+		kfree(icst);
+		pr_err("could not clone ICST params\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &icst_ops;
+	init.flags = CLK_IS_ROOT;
+	init.parent_names = (parent_name ? &parent_name : NULL);
+	init.num_parents = (parent_name ? 1 : 0);
+	icst->hw.init = &init;
+	icst->params = pclone;
+	icst->vcoreg = base + desc->vco_offset;
+	icst->lockreg = base + desc->lock_offset;
+
+	clk = clk_register(dev, &icst->hw);
+	if (IS_ERR(clk))
+		kfree(icst);
+
+	return clk;
+}
+EXPORT_SYMBOL_GPL(icst_clk_register);
diff --git a/kernel/drivers/clk/versatile/clk-icst.h b/kernel/drivers/clk/versatile/clk-icst.h
new file mode 100644
index 000000000..04e6f0aef
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-icst.h
@@ -0,0 +1,20 @@
+#include <asm/hardware/icst.h>
+
+/**
+ * struct clk_icst_desc - descriptor for the ICST VCO
+ * @params: ICST parameters
+ * @vco_offset: offset to the ICST VCO from the provided memory base
+ * @lock_offset: offset to the ICST VCO locking register from the provided
+ *	memory base
+ */
+struct clk_icst_desc {
+	const struct icst_params *params;
+	u32 vco_offset;
+	u32 lock_offset;
+};
+
+struct clk *icst_clk_register(struct device *dev,
+			      const struct clk_icst_desc *desc,
+			      const char *name,
+			      const char *parent_name,
+			      void __iomem *base);
diff --git a/kernel/drivers/clk/versatile/clk-impd1.c b/kernel/drivers/clk/versatile/clk-impd1.c
new file mode 100644
index 000000000..1cc1330dc
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-impd1.c
@@ -0,0 +1,181 @@
+/*
+ * Clock driver for the ARM Integrator/IM-PD1 board
+ * Copyright (C) 2012-2013 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
+ * published by the Free Software Foundation.
+ */
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/platform_data/clk-integrator.h>
+
+#include "clk-icst.h"
+
+#define IMPD1_OSC1	0x00
+#define IMPD1_OSC2	0x04
+#define IMPD1_LOCK	0x08
+
+struct impd1_clk {
+	char *pclkname;
+	struct clk *pclk;
+	char *vco1name;
+	struct clk *vco1clk;
+	char *vco2name;
+	struct clk *vco2clk;
+	struct clk *mmciclk;
+	char *uartname;
+	struct clk *uartclk;
+	char *spiname;
+	struct clk *spiclk;
+	char *scname;
+	struct clk *scclk;
+	struct clk_lookup *clks[15];
+};
+
+/* One entry for each connected IM-PD1 LM */
+static struct impd1_clk impd1_clks[4];
+
+/*
+ * There are two VCO's on the IM-PD1
+ */
+
+static const struct icst_params impd1_vco1_params = {
+	.ref		= 24000000,	/* 24 MHz */
+	.vco_max	= ICST525_VCO_MAX_3V,
+	.vco_min	= ICST525_VCO_MIN,
+	.vd_min		= 12,
+	.vd_max		= 519,
+	.rd_min		= 3,
+	.rd_max		= 120,
+	.s2div		= icst525_s2div,
+	.idx2s		= icst525_idx2s,
+};
+
+static const struct clk_icst_desc impd1_icst1_desc = {
+	.params = &impd1_vco1_params,
+	.vco_offset = IMPD1_OSC1,
+	.lock_offset = IMPD1_LOCK,
+};
+
+static const struct icst_params impd1_vco2_params = {
+	.ref		= 24000000,	/* 24 MHz */
+	.vco_max	= ICST525_VCO_MAX_3V,
+	.vco_min	= ICST525_VCO_MIN,
+	.vd_min		= 12,
+	.vd_max		= 519,
+	.rd_min		= 3,
+	.rd_max		= 120,
+	.s2div		= icst525_s2div,
+	.idx2s		= icst525_idx2s,
+};
+
+static const struct clk_icst_desc impd1_icst2_desc = {
+	.params = &impd1_vco2_params,
+	.vco_offset = IMPD1_OSC2,
+	.lock_offset = IMPD1_LOCK,
+};
+
+/**
+ * integrator_impd1_clk_init() - set up the integrator clock tree
+ * @base: base address of the logic module (LM)
+ * @id: the ID of this LM
+ */
+void integrator_impd1_clk_init(void __iomem *base, unsigned int id)
+{
+	struct impd1_clk *imc;
+	struct clk *clk;
+	struct clk *pclk;
+	int i;
+
+	if (id > 3) {
+		pr_crit("no more than 4 LMs can be attached\n");
+		return;
+	}
+	imc = &impd1_clks[id];
+
+	/* Register the fixed rate PCLK */
+	imc->pclkname = kasprintf(GFP_KERNEL, "lm%x-pclk", id);
+	pclk = clk_register_fixed_rate(NULL, imc->pclkname, NULL,
+				      CLK_IS_ROOT, 0);
+	imc->pclk = pclk;
+
+	imc->vco1name = kasprintf(GFP_KERNEL, "lm%x-vco1", id);
+	clk = icst_clk_register(NULL, &impd1_icst1_desc, imc->vco1name, NULL,
+				base);
+	imc->vco1clk = clk;
+	imc->clks[0] = clkdev_alloc(pclk, "apb_pclk", "lm%x:01000", id);
+	imc->clks[1] = clkdev_alloc(clk, NULL, "lm%x:01000", id);
+
+	/* VCO2 is also called "CLK2" */
+	imc->vco2name = kasprintf(GFP_KERNEL, "lm%x-vco2", id);
+	clk = icst_clk_register(NULL, &impd1_icst2_desc, imc->vco2name, NULL,
+				base);
+	imc->vco2clk = clk;
+
+	/* MMCI uses CLK2 right off */
+	imc->clks[2] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00700", id);
+	imc->clks[3] = clkdev_alloc(clk, NULL, "lm%x:00700", id);
+
+	/* UART reference clock divides CLK2 by a fixed factor 4 */
+	imc->uartname = kasprintf(GFP_KERNEL, "lm%x-uartclk", id);
+	clk = clk_register_fixed_factor(NULL, imc->uartname, imc->vco2name,
+				   CLK_IGNORE_UNUSED, 1, 4);
+	imc->uartclk = clk;
+	imc->clks[4] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00100", id);
+	imc->clks[5] = clkdev_alloc(clk, NULL, "lm%x:00100", id);
+	imc->clks[6] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00200", id);
+	imc->clks[7] = clkdev_alloc(clk, NULL, "lm%x:00200", id);
+
+	/* SPI PL022 clock divides CLK2 by a fixed factor 64 */
+	imc->spiname = kasprintf(GFP_KERNEL, "lm%x-spiclk", id);
+	clk = clk_register_fixed_factor(NULL, imc->spiname, imc->vco2name,
+				   CLK_IGNORE_UNUSED, 1, 64);
+	imc->clks[8] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00300", id);
+	imc->clks[9] = clkdev_alloc(clk, NULL, "lm%x:00300", id);
+
+	/* The GPIO blocks and AACI have only PCLK */
+	imc->clks[10] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00400", id);
+	imc->clks[11] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00500", id);
+	imc->clks[12] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00800", id);
+
+	/* Smart Card clock divides CLK2 by a fixed factor 4 */
+	imc->scname = kasprintf(GFP_KERNEL, "lm%x-scclk", id);
+	clk = clk_register_fixed_factor(NULL, imc->scname, imc->vco2name,
+				   CLK_IGNORE_UNUSED, 1, 4);
+	imc->scclk = clk;
+	imc->clks[13] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00600", id);
+	imc->clks[14] = clkdev_alloc(clk, NULL, "lm%x:00600", id);
+
+	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
+		clkdev_add(imc->clks[i]);
+}
+EXPORT_SYMBOL_GPL(integrator_impd1_clk_init);
+
+void integrator_impd1_clk_exit(unsigned int id)
+{
+	int i;
+	struct impd1_clk *imc;
+
+	if (id > 3)
+		return;
+	imc = &impd1_clks[id];
+
+	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
+		clkdev_drop(imc->clks[i]);
+	clk_unregister(imc->spiclk);
+	clk_unregister(imc->uartclk);
+	clk_unregister(imc->vco2clk);
+	clk_unregister(imc->vco1clk);
+	clk_unregister(imc->pclk);
+	kfree(imc->scname);
+	kfree(imc->spiname);
+	kfree(imc->uartname);
+	kfree(imc->vco2name);
+	kfree(imc->vco1name);
+	kfree(imc->pclkname);
+}
+EXPORT_SYMBOL_GPL(integrator_impd1_clk_exit);
diff --git a/kernel/drivers/clk/versatile/clk-realview.c b/kernel/drivers/clk/versatile/clk-realview.c
new file mode 100644
index 000000000..c8b523117
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-realview.c
@@ -0,0 +1,95 @@
+/*
+ * Clock driver for the ARM RealView boards
+ * Copyright (C) 2012 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
+ * published by the Free Software Foundation.
+ */
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clk-provider.h>
+
+#include <mach/hardware.h>
+#include <mach/platform.h>
+
+#include "clk-icst.h"
+
+/*
+ * Implementation of the ARM RealView clock trees.
+ */
+
+static const struct icst_params realview_oscvco_params = {
+	.ref		= 24000000,
+	.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 const struct clk_icst_desc __initdata realview_osc0_desc = {
+	.params = &realview_oscvco_params,
+	.vco_offset = REALVIEW_SYS_OSC0_OFFSET,
+	.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
+};
+
+static const struct clk_icst_desc __initdata realview_osc4_desc = {
+	.params = &realview_oscvco_params,
+	.vco_offset = REALVIEW_SYS_OSC4_OFFSET,
+	.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
+};
+
+/*
+ * realview_clk_init() - set up the RealView clock tree
+ */
+void __init realview_clk_init(void __iomem *sysbase, bool is_pb1176)
+{
+	struct clk *clk;
+
+	/* APB clock dummy */
+	clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0);
+	clk_register_clkdev(clk, "apb_pclk", NULL);
+
+	/* 24 MHz clock */
+	clk = clk_register_fixed_rate(NULL, "clk24mhz", NULL, CLK_IS_ROOT,
+				24000000);
+	clk_register_clkdev(clk, NULL, "dev:uart0");
+	clk_register_clkdev(clk, NULL, "dev:uart1");
+	clk_register_clkdev(clk, NULL, "dev:uart2");
+	clk_register_clkdev(clk, NULL, "fpga:kmi0");
+	clk_register_clkdev(clk, NULL, "fpga:kmi1");
+	clk_register_clkdev(clk, NULL, "fpga:mmc0");
+	clk_register_clkdev(clk, NULL, "dev:ssp0");
+	if (is_pb1176) {
+		/*
+		 * UART3 is on the dev chip in PB1176
+		 * UART4 only exists in PB1176
+		 */
+		clk_register_clkdev(clk, NULL, "dev:uart3");
+		clk_register_clkdev(clk, NULL, "dev:uart4");
+	} else
+		clk_register_clkdev(clk, NULL, "fpga:uart3");
+
+
+	/* 1 MHz clock */
+	clk = clk_register_fixed_rate(NULL, "clk1mhz", NULL, CLK_IS_ROOT,
+				      1000000);
+	clk_register_clkdev(clk, NULL, "sp804");
+
+	/* ICST VCO clock */
+	if (is_pb1176)
+		clk = icst_clk_register(NULL, &realview_osc0_desc,
+					"osc0", NULL, sysbase);
+	else
+		clk = icst_clk_register(NULL, &realview_osc4_desc,
+					"osc4", NULL, sysbase);
+
+	clk_register_clkdev(clk, NULL, "dev:clcd");
+	clk_register_clkdev(clk, NULL, "issp:clcd");
+}
diff --git a/kernel/drivers/clk/versatile/clk-sp810.c b/kernel/drivers/clk/versatile/clk-sp810.c
new file mode 100644
index 000000000..c6e86a9a2
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-sp810.c
@@ -0,0 +1,188 @@
+/*
+ * 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
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2013 ARM Limited
+ */
+
+#include <linux/amba/sp810.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/err.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;
+	int refclk_index, timclk_index;
+	void __iomem *base;
+	spinlock_t lock;
+	struct clk_sp810_timerclken timerclken[4];
+	struct clk *refclk;
+	struct clk *timclk;
+};
+
+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;
+}
+
+/*
+ * FIXME - setting the parent every time .prepare is invoked is inefficient.
+ * This is better handled by a dedicated clock tree configuration mechanism at
+ * init-time.  Revisit this later when such a mechanism exists
+ */
+static int clk_sp810_timerclken_prepare(struct clk_hw *hw)
+{
+	struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+	struct clk_sp810 *sp810 = timerclken->sp810;
+	struct clk *old_parent = __clk_get_parent(hw->clk);
+	struct clk *new_parent;
+
+	if (!sp810->refclk)
+		sp810->refclk = of_clk_get(sp810->node, sp810->refclk_index);
+
+	if (!sp810->timclk)
+		sp810->timclk = of_clk_get(sp810->node, sp810->timclk_index);
+
+	if (WARN_ON(IS_ERR(sp810->refclk) || IS_ERR(sp810->timclk)))
+		return -ENOENT;
+
+	/* Select fastest parent */
+	if (clk_get_rate(sp810->refclk) > clk_get_rate(sp810->timclk))
+		new_parent = sp810->refclk;
+	else
+		new_parent = sp810->timclk;
+
+	/* Switch the parent if necessary */
+	if (old_parent != new_parent) {
+		clk_prepare(new_parent);
+		clk_set_parent(hw->clk, new_parent);
+		clk_unprepare(old_parent);
+	}
+
+	return 0;
+}
+
+static void clk_sp810_timerclken_unprepare(struct clk_hw *hw)
+{
+	struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+	struct clk_sp810 *sp810 = timerclken->sp810;
+
+	clk_put(sp810->timclk);
+	clk_put(sp810->refclk);
+}
+
+static const struct clk_ops clk_sp810_timerclken_ops = {
+	.prepare = clk_sp810_timerclken_prepare,
+	.unprepare = clk_sp810_timerclken_unprepare,
+	.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;
+}
+
+void __init clk_sp810_of_setup(struct device_node *node)
+{
+	struct clk_sp810 *sp810 = kzalloc(sizeof(*sp810), GFP_KERNEL);
+	const char *parent_names[2];
+	char name[12];
+	struct clk_init_data init;
+	int i;
+
+	if (!sp810) {
+		pr_err("Failed to allocate memory for SP810!\n");
+		return;
+	}
+
+	sp810->refclk_index = of_property_match_string(node, "clock-names",
+			"refclk");
+	parent_names[0] = of_clk_get_parent_name(node, sp810->refclk_index);
+
+	sp810->timclk_index = of_property_match_string(node, "clock-names",
+			"timclk");
+	parent_names[1] = of_clk_get_parent_name(node, sp810->timclk_index);
+
+	if (parent_names[0] <= 0 || parent_names[1] <= 0) {
+		pr_warn("Failed to obtain parent clocks for SP810!\n");
+		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 = CLK_IS_BASIC;
+	init.parent_names = parent_names;
+	init.num_parents = ARRAY_SIZE(parent_names);
+
+	for (i = 0; i < ARRAY_SIZE(sp810->timerclken); i++) {
+		snprintf(name, ARRAY_SIZE(name), "timerclken%d", i);
+
+		sp810->timerclken[i].sp810 = sp810;
+		sp810->timerclken[i].channel = i;
+		sp810->timerclken[i].hw.init = &init;
+
+		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);
+}
+CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup);
diff --git a/kernel/drivers/clk/versatile/clk-versatile.c b/kernel/drivers/clk/versatile/clk-versatile.c
new file mode 100644
index 000000000..7a4f8635b
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-versatile.c
@@ -0,0 +1,101 @@
+/*
+ * Clock driver for the ARM Integrator/AP, Integrator/CP, Versatile AB and
+ * Versatile PB boards.
+ * Copyright (C) 2012 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
+ * published by the Free Software Foundation.
+ */
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include "clk-icst.h"
+
+#define INTEGRATOR_HDR_LOCK_OFFSET	0x14
+
+#define VERSATILE_SYS_OSCCLCD_OFFSET	0x1c
+#define VERSATILE_SYS_LOCK_OFFSET	0x20
+
+/* Base offset for the core module */
+static void __iomem *cm_base;
+
+static const struct icst_params cp_auxosc_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 clk_icst_desc __initdata cm_auxosc_desc = {
+	.params = &cp_auxosc_params,
+	.vco_offset = 0x1c,
+	.lock_offset = INTEGRATOR_HDR_LOCK_OFFSET,
+};
+
+static const struct icst_params versatile_auxosc_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 const struct clk_icst_desc versatile_auxosc_desc __initconst = {
+	.params = &versatile_auxosc_params,
+	.vco_offset = VERSATILE_SYS_OSCCLCD_OFFSET,
+	.lock_offset = VERSATILE_SYS_LOCK_OFFSET,
+};
+static void __init cm_osc_setup(struct device_node *np,
+				const struct clk_icst_desc *desc)
+{
+	struct clk *clk = ERR_PTR(-EINVAL);
+	const char *clk_name = np->name;
+	const char *parent_name;
+
+	if (!cm_base) {
+		/* Remap the core module base if not done yet */
+		struct device_node *parent;
+
+		parent = of_get_parent(np);
+		if (!parent) {
+			pr_err("no parent on core module clock\n");
+			return;
+		}
+		cm_base = of_iomap(parent, 0);
+		if (!cm_base) {
+			pr_err("could not remap core module base\n");
+			return;
+		}
+	}
+
+	parent_name = of_clk_get_parent_name(np, 0);
+	clk = icst_clk_register(NULL, desc, clk_name, parent_name, cm_base);
+	if (!IS_ERR(clk))
+		of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+
+static void __init of_integrator_cm_osc_setup(struct device_node *np)
+{
+	cm_osc_setup(np, &cm_auxosc_desc);
+}
+CLK_OF_DECLARE(integrator_cm_auxosc_clk,
+	"arm,integrator-cm-auxosc", of_integrator_cm_osc_setup);
+
+static void __init of_versatile_cm_osc_setup(struct device_node *np)
+{
+	cm_osc_setup(np, &versatile_auxosc_desc);
+}
+CLK_OF_DECLARE(versatile_cm_auxosc_clk,
+	       "arm,versatile-cm-auxosc", of_versatile_cm_osc_setup);
diff --git a/kernel/drivers/clk/versatile/clk-vexpress-osc.c b/kernel/drivers/clk/versatile/clk-vexpress-osc.c
new file mode 100644
index 000000000..89c0609e1
--- /dev/null
+++ b/kernel/drivers/clk/versatile/clk-vexpress-osc.c
@@ -0,0 +1,130 @@
+/*
+ * 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
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/vexpress.h>
+
+struct vexpress_osc {
+	struct regmap *reg;
+	struct clk_hw hw;
+	unsigned long rate_min;
+	unsigned long rate_max;
+};
+
+#define to_vexpress_osc(osc) container_of(osc, struct vexpress_osc, hw)
+
+static unsigned long vexpress_osc_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+	u32 rate;
+
+	regmap_read(osc->reg, 0, &rate);
+
+	return rate;
+}
+
+static long vexpress_osc_round_rate(struct clk_hw *hw, unsigned long rate,
+		unsigned long *parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+
+	if (WARN_ON(osc->rate_min && rate < osc->rate_min))
+		rate = osc->rate_min;
+
+	if (WARN_ON(osc->rate_max && rate > osc->rate_max))
+		rate = osc->rate_max;
+
+	return rate;
+}
+
+static int vexpress_osc_set_rate(struct clk_hw *hw, unsigned long rate,
+		unsigned long parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+
+	return regmap_write(osc->reg, 0, rate);
+}
+
+static struct clk_ops vexpress_osc_ops = {
+	.recalc_rate = vexpress_osc_recalc_rate,
+	.round_rate = vexpress_osc_round_rate,
+	.set_rate = vexpress_osc_set_rate,
+};
+
+
+static int vexpress_osc_probe(struct platform_device *pdev)
+{
+	struct clk_init_data init;
+	struct vexpress_osc *osc;
+	struct clk *clk;
+	u32 range[2];
+
+	osc = devm_kzalloc(&pdev->dev, sizeof(*osc), GFP_KERNEL);
+	if (!osc)
+		return -ENOMEM;
+
+	osc->reg = devm_regmap_init_vexpress_config(&pdev->dev);
+	if (IS_ERR(osc->reg))
+		return PTR_ERR(osc->reg);
+
+	if (of_property_read_u32_array(pdev->dev.of_node, "freq-range", range,
+			ARRAY_SIZE(range)) == 0) {
+		osc->rate_min = range[0];
+		osc->rate_max = range[1];
+	}
+
+	if (of_property_read_string(pdev->dev.of_node, "clock-output-names",
+			&init.name) != 0)
+		init.name = dev_name(&pdev->dev);
+
+	init.ops = &vexpress_osc_ops;
+	init.flags = CLK_IS_ROOT;
+	init.num_parents = 0;
+
+	osc->hw.init = &init;
+
+	clk = clk_register(NULL, &osc->hw);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get, clk);
+
+	dev_dbg(&pdev->dev, "Registered clock '%s'\n", init.name);
+
+	return 0;
+}
+
+static const struct of_device_id vexpress_osc_of_match[] = {
+	{ .compatible = "arm,vexpress-osc", },
+	{}
+};
+
+static struct platform_driver vexpress_osc_driver = {
+	.driver	= {
+		.name = "vexpress-osc",
+		.of_match_table = vexpress_osc_of_match,
+	},
+	.probe = vexpress_osc_probe,
+};
+
+static int __init vexpress_osc_init(void)
+{
+	return platform_driver_register(&vexpress_osc_driver);
+}
+core_initcall(vexpress_osc_init);