zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/arch/arm/mach-ux500/clock.c b/ap/os/linux/linux-3.4.x/arch/arm/mach-ux500/clock.c
new file mode 100644
index 0000000..ec35f0a
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/arch/arm/mach-ux500/clock.c
@@ -0,0 +1,723 @@
+/*
+ *  Copyright (C) 2009 ST-Ericsson
+ *  Copyright (C) 2009 STMicroelectronics
+ *
+ * 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/module.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/clkdev.h>
+#include <linux/cpufreq.h>
+
+#include <plat/mtu.h>
+#include <mach/hardware.h>
+#include "clock.h"
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>	/* for copy_from_user */
+static LIST_HEAD(clk_list);
+#endif
+
+#define PRCC_PCKEN		0x00
+#define PRCC_PCKDIS		0x04
+#define PRCC_KCKEN		0x08
+#define PRCC_KCKDIS		0x0C
+
+#define PRCM_YYCLKEN0_MGT_SET	0x510
+#define PRCM_YYCLKEN1_MGT_SET	0x514
+#define PRCM_YYCLKEN0_MGT_CLR	0x518
+#define PRCM_YYCLKEN1_MGT_CLR	0x51C
+#define PRCM_YYCLKEN0_MGT_VAL	0x520
+#define PRCM_YYCLKEN1_MGT_VAL	0x524
+
+#define PRCM_SVAMMDSPCLK_MGT	0x008
+#define PRCM_SIAMMDSPCLK_MGT	0x00C
+#define PRCM_SGACLK_MGT		0x014
+#define PRCM_UARTCLK_MGT	0x018
+#define PRCM_MSP02CLK_MGT	0x01C
+#define PRCM_MSP1CLK_MGT	0x288
+#define PRCM_I2CCLK_MGT		0x020
+#define PRCM_SDMMCCLK_MGT	0x024
+#define PRCM_SLIMCLK_MGT	0x028
+#define PRCM_PER1CLK_MGT	0x02C
+#define PRCM_PER2CLK_MGT	0x030
+#define PRCM_PER3CLK_MGT	0x034
+#define PRCM_PER5CLK_MGT	0x038
+#define PRCM_PER6CLK_MGT	0x03C
+#define PRCM_PER7CLK_MGT	0x040
+#define PRCM_LCDCLK_MGT		0x044
+#define PRCM_BMLCLK_MGT		0x04C
+#define PRCM_HSITXCLK_MGT	0x050
+#define PRCM_HSIRXCLK_MGT	0x054
+#define PRCM_HDMICLK_MGT	0x058
+#define PRCM_APEATCLK_MGT	0x05C
+#define PRCM_APETRACECLK_MGT	0x060
+#define PRCM_MCDECLK_MGT	0x064
+#define PRCM_IPI2CCLK_MGT	0x068
+#define PRCM_DSIALTCLK_MGT	0x06C
+#define PRCM_DMACLK_MGT		0x074
+#define PRCM_B2R2CLK_MGT	0x078
+#define PRCM_TVCLK_MGT		0x07C
+#define PRCM_TCR		0x1C8
+#define PRCM_TCR_STOPPED	(1 << 16)
+#define PRCM_TCR_DOZE_MODE	(1 << 17)
+#define PRCM_UNIPROCLK_MGT	0x278
+#define PRCM_SSPCLK_MGT		0x280
+#define PRCM_RNGCLK_MGT		0x284
+#define PRCM_UICCCLK_MGT	0x27C
+
+#define PRCM_MGT_ENABLE		(1 << 8)
+
+static DEFINE_SPINLOCK(clocks_lock);
+
+static void __clk_enable(struct clk *clk)
+{
+	if (clk->enabled++ == 0) {
+		if (clk->parent_cluster)
+			__clk_enable(clk->parent_cluster);
+
+		if (clk->parent_periph)
+			__clk_enable(clk->parent_periph);
+
+		if (clk->ops && clk->ops->enable)
+			clk->ops->enable(clk);
+	}
+}
+
+int clk_enable(struct clk *clk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	__clk_enable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+static void __clk_disable(struct clk *clk)
+{
+	if (--clk->enabled == 0) {
+		if (clk->ops && clk->ops->disable)
+			clk->ops->disable(clk);
+
+		if (clk->parent_periph)
+			__clk_disable(clk->parent_periph);
+
+		if (clk->parent_cluster)
+			__clk_disable(clk->parent_cluster);
+	}
+}
+
+void clk_disable(struct clk *clk)
+{
+	unsigned long flags;
+
+	WARN_ON(!clk->enabled);
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	__clk_disable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+/*
+ * The MTU has a separate, rather complex muxing setup
+ * with alternative parents (peripheral cluster or
+ * ULP or fixed 32768 Hz) depending on settings
+ */
+static unsigned long clk_mtu_get_rate(struct clk *clk)
+{
+	void __iomem *addr;
+	u32 tcr;
+	int mtu = (int) clk->data;
+	/*
+	 * One of these is selected eventually
+	 * TODO: Replace the constant with a reference
+	 * to the ULP source once this is modeled.
+	 */
+	unsigned long clk32k = 32768;
+	unsigned long mturate;
+	unsigned long retclk;
+
+	if (cpu_is_u5500())
+		addr = __io_address(U5500_PRCMU_BASE);
+	else if (cpu_is_u8500())
+		addr = __io_address(U8500_PRCMU_BASE);
+	else
+		ux500_unknown_soc();
+
+	/*
+	 * On a startup, always conifgure the TCR to the doze mode;
+	 * bootloaders do it for us. Do this in the kernel too.
+	 */
+	writel(PRCM_TCR_DOZE_MODE, addr + PRCM_TCR);
+
+	tcr = readl(addr + PRCM_TCR);
+
+	/* Get the rate from the parent as a default */
+	if (clk->parent_periph)
+		mturate = clk_get_rate(clk->parent_periph);
+	else if (clk->parent_cluster)
+		mturate = clk_get_rate(clk->parent_cluster);
+	else
+		/* We need to be connected SOMEWHERE */
+		BUG();
+
+	/* Return the clock selected for this MTU */
+	if (tcr & (1 << mtu))
+		retclk = clk32k;
+	else
+		retclk = mturate;
+
+	pr_info("MTU%d clock rate: %lu Hz\n", mtu, retclk);
+	return retclk;
+}
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	unsigned long rate;
+
+	/*
+	 * If there is a custom getrate callback for this clock,
+	 * it will take precedence.
+	 */
+	if (clk->get_rate)
+		return clk->get_rate(clk);
+
+	if (clk->ops && clk->ops->get_rate)
+		return clk->ops->get_rate(clk);
+
+	rate = clk->rate;
+	if (!rate) {
+		if (clk->parent_periph)
+			rate = clk_get_rate(clk->parent_periph);
+		else if (clk->parent_cluster)
+			rate = clk_get_rate(clk->parent_cluster);
+	}
+
+	return rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+	/*TODO*/
+	return rate;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+	clk->rate = rate;
+	return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	/*TODO*/
+	return -ENOSYS;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+static void clk_prcmu_enable(struct clk *clk)
+{
+	void __iomem *cg_set_reg = __io_address(U8500_PRCMU_BASE)
+				   + PRCM_YYCLKEN0_MGT_SET + clk->prcmu_cg_off;
+
+	writel(1 << clk->prcmu_cg_bit, cg_set_reg);
+}
+
+static void clk_prcmu_disable(struct clk *clk)
+{
+	void __iomem *cg_clr_reg = __io_address(U8500_PRCMU_BASE)
+				   + PRCM_YYCLKEN0_MGT_CLR + clk->prcmu_cg_off;
+
+	writel(1 << clk->prcmu_cg_bit, cg_clr_reg);
+}
+
+static struct clkops clk_prcmu_ops = {
+	.enable = clk_prcmu_enable,
+	.disable = clk_prcmu_disable,
+};
+
+static unsigned int clkrst_base[] = {
+	[1] = U8500_CLKRST1_BASE,
+	[2] = U8500_CLKRST2_BASE,
+	[3] = U8500_CLKRST3_BASE,
+	[5] = U8500_CLKRST5_BASE,
+	[6] = U8500_CLKRST6_BASE,
+};
+
+static void clk_prcc_enable(struct clk *clk)
+{
+	void __iomem *addr = __io_address(clkrst_base[clk->cluster]);
+
+	if (clk->prcc_kernel != -1)
+		writel(1 << clk->prcc_kernel, addr + PRCC_KCKEN);
+
+	if (clk->prcc_bus != -1)
+		writel(1 << clk->prcc_bus, addr + PRCC_PCKEN);
+}
+
+static void clk_prcc_disable(struct clk *clk)
+{
+	void __iomem *addr = __io_address(clkrst_base[clk->cluster]);
+
+	if (clk->prcc_bus != -1)
+		writel(1 << clk->prcc_bus, addr + PRCC_PCKDIS);
+
+	if (clk->prcc_kernel != -1)
+		writel(1 << clk->prcc_kernel, addr + PRCC_KCKDIS);
+}
+
+static struct clkops clk_prcc_ops = {
+	.enable = clk_prcc_enable,
+	.disable = clk_prcc_disable,
+};
+
+static struct clk clk_32khz = {
+	.name =  "clk_32khz",
+	.rate = 32000,
+};
+
+/*
+ * PRCMU level clock gating
+ */
+
+/* Bank 0 */
+static DEFINE_PRCMU_CLK(svaclk,		0x0, 2, SVAMMDSPCLK);
+static DEFINE_PRCMU_CLK(siaclk,		0x0, 3, SIAMMDSPCLK);
+static DEFINE_PRCMU_CLK(sgaclk,		0x0, 4, SGACLK);
+static DEFINE_PRCMU_CLK_RATE(uartclk,	0x0, 5, UARTCLK, 38400000);
+static DEFINE_PRCMU_CLK(msp02clk,	0x0, 6, MSP02CLK);
+static DEFINE_PRCMU_CLK(msp1clk,	0x0, 7, MSP1CLK); /* v1 */
+static DEFINE_PRCMU_CLK_RATE(i2cclk,	0x0, 8, I2CCLK, 48000000);
+static DEFINE_PRCMU_CLK_RATE(sdmmcclk,	0x0, 9, SDMMCCLK, 100000000);
+static DEFINE_PRCMU_CLK(slimclk,	0x0, 10, SLIMCLK);
+static DEFINE_PRCMU_CLK(per1clk,	0x0, 11, PER1CLK);
+static DEFINE_PRCMU_CLK(per2clk,	0x0, 12, PER2CLK);
+static DEFINE_PRCMU_CLK(per3clk,	0x0, 13, PER3CLK);
+static DEFINE_PRCMU_CLK(per5clk,	0x0, 14, PER5CLK);
+static DEFINE_PRCMU_CLK_RATE(per6clk,	0x0, 15, PER6CLK, 133330000);
+static DEFINE_PRCMU_CLK(lcdclk,		0x0, 17, LCDCLK);
+static DEFINE_PRCMU_CLK(bmlclk,		0x0, 18, BMLCLK);
+static DEFINE_PRCMU_CLK(hsitxclk,	0x0, 19, HSITXCLK);
+static DEFINE_PRCMU_CLK(hsirxclk,	0x0, 20, HSIRXCLK);
+static DEFINE_PRCMU_CLK(hdmiclk,	0x0, 21, HDMICLK);
+static DEFINE_PRCMU_CLK(apeatclk,	0x0, 22, APEATCLK);
+static DEFINE_PRCMU_CLK(apetraceclk,	0x0, 23, APETRACECLK);
+static DEFINE_PRCMU_CLK(mcdeclk,	0x0, 24, MCDECLK);
+static DEFINE_PRCMU_CLK(ipi2clk,	0x0, 25, IPI2CCLK);
+static DEFINE_PRCMU_CLK(dsialtclk,	0x0, 26, DSIALTCLK); /* v1 */
+static DEFINE_PRCMU_CLK(dmaclk,		0x0, 27, DMACLK);
+static DEFINE_PRCMU_CLK(b2r2clk,	0x0, 28, B2R2CLK);
+static DEFINE_PRCMU_CLK(tvclk,		0x0, 29, TVCLK);
+static DEFINE_PRCMU_CLK(uniproclk,	0x0, 30, UNIPROCLK); /* v1 */
+static DEFINE_PRCMU_CLK_RATE(sspclk,	0x0, 31, SSPCLK, 48000000); /* v1 */
+
+/* Bank 1 */
+static DEFINE_PRCMU_CLK(rngclk,		0x4, 0, RNGCLK); /* v1 */
+static DEFINE_PRCMU_CLK(uiccclk,	0x4, 1, UICCCLK); /* v1 */
+
+/*
+ * PRCC level clock gating
+ * Format: per#, clk, PCKEN bit, KCKEN bit, parent
+ */
+
+/* Peripheral Cluster #1 */
+static DEFINE_PRCC_CLK(1, i2c4,		10, 9, &clk_i2cclk);
+static DEFINE_PRCC_CLK(1, gpio0,	9, -1, NULL);
+static DEFINE_PRCC_CLK(1, slimbus0,	8,  8, &clk_slimclk);
+static DEFINE_PRCC_CLK(1, spi3,		7, -1, NULL);
+static DEFINE_PRCC_CLK(1, i2c2,		6,  6, &clk_i2cclk);
+static DEFINE_PRCC_CLK(1, sdi0,		5,  5, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(1, msp1,		4,  4, &clk_msp1clk);
+static DEFINE_PRCC_CLK(1, msp0,		3,  3, &clk_msp02clk);
+static DEFINE_PRCC_CLK(1, i2c1,		2,  2, &clk_i2cclk);
+static DEFINE_PRCC_CLK(1, uart1,	1,  1, &clk_uartclk);
+static DEFINE_PRCC_CLK(1, uart0,	0,  0, &clk_uartclk);
+
+/* Peripheral Cluster #2 */
+static DEFINE_PRCC_CLK(2, gpio1,	11, -1, NULL);
+static DEFINE_PRCC_CLK(2, ssitx,	10,  7, NULL);
+static DEFINE_PRCC_CLK(2, ssirx,	 9,  6, NULL);
+static DEFINE_PRCC_CLK(2, spi0,		8, -1, NULL);
+static DEFINE_PRCC_CLK(2, sdi3,		7,  5, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(2, sdi1,		6,  4, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(2, msp2,		5,  3, &clk_msp02clk);
+static DEFINE_PRCC_CLK(2, sdi4,		4,  2, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(2, pwl,		3,  1, NULL);
+static DEFINE_PRCC_CLK(2, spi1,		2, -1, NULL);
+static DEFINE_PRCC_CLK(2, spi2,		1, -1, NULL);
+static DEFINE_PRCC_CLK(2, i2c3,		0,  0, &clk_i2cclk);
+
+/* Peripheral Cluster #3 */
+static DEFINE_PRCC_CLK(3, gpio2,	8, -1, NULL);
+static DEFINE_PRCC_CLK(3, sdi5,		7,  7, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(3, uart2,	6,  6, &clk_uartclk);
+static DEFINE_PRCC_CLK(3, ske,		5,  5, &clk_32khz);
+static DEFINE_PRCC_CLK(3, sdi2,		4,  4, &clk_sdmmcclk);
+static DEFINE_PRCC_CLK(3, i2c0,		3,  3, &clk_i2cclk);
+static DEFINE_PRCC_CLK(3, ssp1,		2,  2, &clk_sspclk);
+static DEFINE_PRCC_CLK(3, ssp0,		1,  1, &clk_sspclk);
+static DEFINE_PRCC_CLK(3, fsmc,		0, -1, NULL);
+
+/* Peripheral Cluster #4 is in the always on domain */
+
+/* Peripheral Cluster #5 */
+static DEFINE_PRCC_CLK(5, gpio3,	1, -1, NULL);
+static DEFINE_PRCC_CLK(5, usb,		0,  0, NULL);
+
+/* Peripheral Cluster #6 */
+
+/* MTU ID in data */
+static DEFINE_PRCC_CLK_CUSTOM(6, mtu1, 8, -1, NULL, clk_mtu_get_rate, 1);
+static DEFINE_PRCC_CLK_CUSTOM(6, mtu0, 7, -1, NULL, clk_mtu_get_rate, 0);
+static DEFINE_PRCC_CLK(6, cfgreg,	6,  6, NULL);
+static DEFINE_PRCC_CLK(6, hash1,	5, -1, NULL);
+static DEFINE_PRCC_CLK(6, unipro,	4,  1, &clk_uniproclk);
+static DEFINE_PRCC_CLK(6, pka,		3, -1, NULL);
+static DEFINE_PRCC_CLK(6, hash0,	2, -1, NULL);
+static DEFINE_PRCC_CLK(6, cryp0,	1, -1, NULL);
+static DEFINE_PRCC_CLK(6, rng,	0,  0, &clk_rngclk);
+
+static struct clk clk_dummy_apb_pclk = {
+	.name = "apb_pclk",
+};
+
+static struct clk_lookup u8500_clks[] = {
+	CLK(dummy_apb_pclk, NULL,	"apb_pclk"),
+
+	/* Peripheral Cluster #1 */
+	CLK(gpio0,	"gpio.0",	NULL),
+	CLK(gpio0,	"gpio.1",	NULL),
+	CLK(slimbus0,	"slimbus0",	NULL),
+	CLK(i2c2,	"nmk-i2c.2",	NULL),
+	CLK(sdi0,	"sdi0",		NULL),
+	CLK(msp0,	"msp0",		NULL),
+	CLK(i2c1,	"nmk-i2c.1",	NULL),
+	CLK(uart1,	"uart1",	NULL),
+	CLK(uart0,	"uart0",	NULL),
+
+	/* Peripheral Cluster #3 */
+	CLK(gpio2,	"gpio.2",	NULL),
+	CLK(gpio2,	"gpio.3",	NULL),
+	CLK(gpio2,	"gpio.4",	NULL),
+	CLK(gpio2,	"gpio.5",	NULL),
+	CLK(sdi5,	"sdi5",		NULL),
+	CLK(uart2,	"uart2",	NULL),
+	CLK(ske,	"ske",		NULL),
+	CLK(ske,	"nmk-ske-keypad",	NULL),
+	CLK(sdi2,	"sdi2",		NULL),
+	CLK(i2c0,	"nmk-i2c.0",	NULL),
+	CLK(fsmc,	"fsmc",		NULL),
+
+	/* Peripheral Cluster #5 */
+	CLK(gpio3,	"gpio.8",	NULL),
+
+	/* Peripheral Cluster #6 */
+	CLK(hash1,	"hash1",	NULL),
+	CLK(pka,	"pka",		NULL),
+	CLK(hash0,	"hash0",	NULL),
+	CLK(cryp0,	"cryp0",	NULL),
+
+	/* PRCMU level clock gating */
+
+	/* Bank 0 */
+	CLK(svaclk,	"sva",		NULL),
+	CLK(siaclk,	"sia",		NULL),
+	CLK(sgaclk,	"sga",		NULL),
+	CLK(slimclk,	"slim",		NULL),
+	CLK(lcdclk,	"lcd",		NULL),
+	CLK(bmlclk,	"bml",		NULL),
+	CLK(hsitxclk,	"stm-hsi.0",	NULL),
+	CLK(hsirxclk,	"stm-hsi.1",	NULL),
+	CLK(hdmiclk,	"hdmi",		NULL),
+	CLK(apeatclk,	"apeat",	NULL),
+	CLK(apetraceclk,	"apetrace",	NULL),
+	CLK(mcdeclk,	"mcde",		NULL),
+	CLK(ipi2clk,	"ipi2",		NULL),
+	CLK(dmaclk,	"dma40.0",	NULL),
+	CLK(b2r2clk,	"b2r2",		NULL),
+	CLK(tvclk,	"tv",		NULL),
+
+	/* Peripheral Cluster #1 */
+	CLK(i2c4,	"nmk-i2c.4",	NULL),
+	CLK(spi3,	"spi3",		NULL),
+	CLK(msp1,	"msp1",		NULL),
+
+	/* Peripheral Cluster #2 */
+	CLK(gpio1,	"gpio.6",	NULL),
+	CLK(gpio1,	"gpio.7",	NULL),
+	CLK(ssitx,	"ssitx",	NULL),
+	CLK(ssirx,	"ssirx",	NULL),
+	CLK(spi0,	"spi0",		NULL),
+	CLK(sdi3,	"sdi3",		NULL),
+	CLK(sdi1,	"sdi1",		NULL),
+	CLK(msp2,	"msp2",		NULL),
+	CLK(sdi4,	"sdi4",		NULL),
+	CLK(pwl,	"pwl",		NULL),
+	CLK(spi1,	"spi1",		NULL),
+	CLK(spi2,	"spi2",		NULL),
+	CLK(i2c3,	"nmk-i2c.3",	NULL),
+
+	/* Peripheral Cluster #3 */
+	CLK(ssp1,	"ssp1",		NULL),
+	CLK(ssp0,	"ssp0",		NULL),
+
+	/* Peripheral Cluster #5 */
+	CLK(usb,	"musb-ux500.0",	"usb"),
+
+	/* Peripheral Cluster #6 */
+	CLK(mtu1,	"mtu1",		NULL),
+	CLK(mtu0,	"mtu0",		NULL),
+	CLK(cfgreg,	"cfgreg",	NULL),
+	CLK(hash1,	"hash1",	NULL),
+	CLK(unipro,	"unipro",	NULL),
+	CLK(rng,	"rng",		NULL),
+
+	/* PRCMU level clock gating */
+
+	/* Bank 0 */
+	CLK(uniproclk,	"uniproclk",	NULL),
+	CLK(dsialtclk,	"dsialt",	NULL),
+
+	/* Bank 1 */
+	CLK(rngclk,	"rng",		NULL),
+	CLK(uiccclk,	"uicc",		NULL),
+};
+
+#ifdef CONFIG_DEBUG_FS
+/*
+ *	debugfs support to trace clock tree hierarchy and attributes with
+ *	powerdebug
+ */
+static struct dentry *clk_debugfs_root;
+
+void __init clk_debugfs_add_table(struct clk_lookup *cl, size_t num)
+{
+	while (num--) {
+		/* Check that the clock has not been already registered */
+		if (!(cl->clk->list.prev != cl->clk->list.next))
+			list_add_tail(&cl->clk->list, &clk_list);
+
+		cl++;
+	}
+}
+
+static ssize_t usecount_dbg_read(struct file *file, char __user *buf,
+						  size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char cusecount[128];
+	unsigned int len;
+
+	len = sprintf(cusecount, "%u\n", clk->enabled);
+	return simple_read_from_buffer(buf, size, off, cusecount, len);
+}
+
+static ssize_t rate_dbg_read(struct file *file, char __user *buf,
+					  size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char crate[128];
+	unsigned int rate;
+	unsigned int len;
+
+	rate = clk_get_rate(clk);
+	len = sprintf(crate, "%u\n", rate);
+	return simple_read_from_buffer(buf, size, off, crate, len);
+}
+
+static const struct file_operations usecount_fops = {
+	.read = usecount_dbg_read,
+};
+
+static const struct file_operations set_rate_fops = {
+	.read = rate_dbg_read,
+};
+
+static struct dentry *clk_debugfs_register_dir(struct clk *c,
+						struct dentry *p_dentry)
+{
+	struct dentry *d, *clk_d;
+	const char *p = c->name;
+
+	if (!p)
+		p = "BUG";
+
+	clk_d = debugfs_create_dir(p, p_dentry);
+	if (!clk_d)
+		return NULL;
+
+	d = debugfs_create_file("usecount", S_IRUGO,
+				clk_d, c, &usecount_fops);
+	if (!d)
+		goto err_out;
+	d = debugfs_create_file("rate", S_IRUGO,
+				clk_d, c, &set_rate_fops);
+	if (!d)
+		goto err_out;
+	/*
+	 * TODO : not currently available in ux500
+	 * d = debugfs_create_x32("flags", S_IRUGO, clk_d, (u32 *)&c->flags);
+	 * if (!d)
+	 *	goto err_out;
+	 */
+
+	return clk_d;
+
+err_out:
+	debugfs_remove_recursive(clk_d);
+	return NULL;
+}
+
+static int clk_debugfs_register_one(struct clk *c)
+{
+	struct clk *pa = c->parent_periph;
+	struct clk *bpa = c->parent_cluster;
+
+	if (!(bpa && !pa)) {
+		c->dent = clk_debugfs_register_dir(c,
+				pa ? pa->dent : clk_debugfs_root);
+		if (!c->dent)
+			return -ENOMEM;
+	}
+
+	if (bpa) {
+		c->dent_bus = clk_debugfs_register_dir(c,
+				bpa->dent_bus ? bpa->dent_bus : bpa->dent);
+		if ((!c->dent_bus) &&  (c->dent)) {
+			debugfs_remove_recursive(c->dent);
+			c->dent = NULL;
+			return -ENOMEM;
+		}
+	}
+	return 0;
+}
+
+static int clk_debugfs_register(struct clk *c)
+{
+	int err;
+	struct clk *pa = c->parent_periph;
+	struct clk *bpa = c->parent_cluster;
+
+	if (pa && (!pa->dent && !pa->dent_bus)) {
+		err = clk_debugfs_register(pa);
+		if (err)
+			return err;
+	}
+
+	if (bpa && (!bpa->dent && !bpa->dent_bus)) {
+		err = clk_debugfs_register(bpa);
+		if (err)
+			return err;
+	}
+
+	if ((!c->dent) && (!c->dent_bus)) {
+		err = clk_debugfs_register_one(c);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static int __init clk_debugfs_init(void)
+{
+	struct clk *c;
+	struct dentry *d;
+	int err;
+
+	d = debugfs_create_dir("clock", NULL);
+	if (!d)
+		return -ENOMEM;
+	clk_debugfs_root = d;
+
+	list_for_each_entry(c, &clk_list, list) {
+		err = clk_debugfs_register(c);
+		if (err)
+			goto err_out;
+	}
+	return 0;
+err_out:
+	debugfs_remove_recursive(clk_debugfs_root);
+	return err;
+}
+
+late_initcall(clk_debugfs_init);
+#endif /* defined(CONFIG_DEBUG_FS) */
+
+unsigned long clk_smp_twd_rate = 500000000;
+
+unsigned long clk_smp_twd_get_rate(struct clk *clk)
+{
+	return clk_smp_twd_rate;
+}
+
+static struct clk clk_smp_twd = {
+	.get_rate = clk_smp_twd_get_rate,
+	.name =  "smp_twd",
+};
+
+static struct clk_lookup clk_smp_twd_lookup = {
+	.dev_id = "smp_twd",
+	.clk = &clk_smp_twd,
+};
+
+#ifdef CONFIG_CPU_FREQ
+
+static int clk_twd_cpufreq_transition(struct notifier_block *nb,
+				      unsigned long state, void *data)
+{
+	struct cpufreq_freqs *f = data;
+
+	if (state == CPUFREQ_PRECHANGE) {
+		/* Save frequency in simple Hz */
+		clk_smp_twd_rate = (f->new * 1000) / 2;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block clk_twd_cpufreq_nb = {
+	.notifier_call = clk_twd_cpufreq_transition,
+};
+
+static int clk_init_smp_twd_cpufreq(void)
+{
+	return cpufreq_register_notifier(&clk_twd_cpufreq_nb,
+				  CPUFREQ_TRANSITION_NOTIFIER);
+}
+late_initcall(clk_init_smp_twd_cpufreq);
+
+#endif
+
+int __init clk_init(void)
+{
+	if (cpu_is_u5500()) {
+		/* Clock tree for U5500 not implemented yet */
+		clk_prcc_ops.enable = clk_prcc_ops.disable = NULL;
+		clk_prcmu_ops.enable = clk_prcmu_ops.disable = NULL;
+		clk_uartclk.rate = 36360000;
+		clk_sdmmcclk.rate = 99900000;
+	}
+
+	clkdev_add_table(u8500_clks, ARRAY_SIZE(u8500_clks));
+	clkdev_add(&clk_smp_twd_lookup);
+
+#ifdef CONFIG_DEBUG_FS
+	clk_debugfs_add_table(u8500_clks, ARRAY_SIZE(u8500_clks));
+#endif
+	return 0;
+}