ARM: 6703/1: SPEAr: update clk API support

- Add support for divisor per parent clock
- Add ENABLED_ON_INIT feature in clk
- Add clk_set_rate(), round_rate_index & clk_round_rate()
- Simplify clk_recalc functions
- Add/update clock definitions

Reviewed-by: Stanley Miao <stanley.miao@windriver.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: shiraz hashim <shiraz.hashim@st.com>
Signed-off-by: Rajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 649 insertions, 150 deletions

diff --git a/arch/arm/plat-spear/clock.c b/arch/arm/plat-spear/clock.c
index f1cf832e4e3..7e7ab606dc4 100644
--- a/arch/arm/plat-spear/clock.c
+++ b/arch/arm/plat-spear/clock.c
@@ -12,6 +12,7 @@
  */
 
 #include <linux/bug.h>
+#include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/list.h>
@@ -22,7 +23,7 @@
 static DEFINE_SPINLOCK(clocks_lock);
 static LIST_HEAD(root_clks);
 
-static void propagate_rate(struct list_head *);
+static void propagate_rate(struct clk *, int on_init);
 
 static int generic_clk_enable(struct clk *clk)
 {
@@ -64,6 +65,100 @@ static struct clkops generic_clkops = {
 	.disable = generic_clk_disable,
 };
 
+/* returns current programmed clocks clock info structure */
+static struct pclk_info *pclk_info_get(struct clk *clk)
+{
+	unsigned int val, i;
+	struct pclk_info *info = NULL;
+
+	val = (readl(clk->pclk_sel->pclk_sel_reg) >> clk->pclk_sel_shift)
+		& clk->pclk_sel->pclk_sel_mask;
+
+	for (i = 0; i < clk->pclk_sel->pclk_count; i++) {
+		if (clk->pclk_sel->pclk_info[i].pclk_val == val)
+			info = &clk->pclk_sel->pclk_info[i];
+	}
+
+	return info;
+}
+
+/*
+ * Set Update pclk, and pclk_info of clk and add clock sibling node to current
+ * parents children list
+ */
+static void clk_reparent(struct clk *clk, struct pclk_info *pclk_info)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	list_del(&clk->sibling);
+	list_add(&clk->sibling, &pclk_info->pclk->children);
+
+	clk->pclk = pclk_info->pclk;
+	spin_unlock_irqrestore(&clocks_lock, flags);
+}
+
+static void do_clk_disable(struct clk *clk)
+{
+	if (!clk)
+		return;
+
+	if (!clk->usage_count) {
+		WARN_ON(1);
+		return;
+	}
+
+	clk->usage_count--;
+
+	if (clk->usage_count == 0) {
+		/*
+		 * Surely, there are no active childrens or direct users
+		 * of this clock
+		 */
+		if (clk->pclk)
+			do_clk_disable(clk->pclk);
+
+		if (clk->ops && clk->ops->disable)
+			clk->ops->disable(clk);
+	}
+}
+
+static int do_clk_enable(struct clk *clk)
+{
+	int ret = 0;
+
+	if (!clk)
+		return -EFAULT;
+
+	if (clk->usage_count == 0) {
+		if (clk->pclk) {
+			ret = do_clk_enable(clk->pclk);
+			if (ret)
+				goto err;
+		}
+		if (clk->ops && clk->ops->enable) {
+			ret = clk->ops->enable(clk);
+			if (ret) {
+				if (clk->pclk)
+					do_clk_disable(clk->pclk);
+				goto err;
+			}
+		}
+		/*
+		 * Since the clock is going to be used for the first
+		 * time please reclac
+		 */
+		if (clk->recalc) {
+			ret = clk->recalc(clk);
+			if (ret)
+				goto err;
+		}
+	}
+	clk->usage_count++;
+err:
+	return ret;
+}
+
 /*
  * clk_enable - inform the system when the clock source should be running.
  * @clk: clock source
@@ -77,17 +172,9 @@ int clk_enable(struct clk *clk)
 	unsigned long flags;
 	int ret = 0;
 
-	if (!clk || IS_ERR(clk))
-		return -EFAULT;
-
 	spin_lock_irqsave(&clocks_lock, flags);
-	if (clk->usage_count == 0) {
-		if (clk->ops && clk->ops->enable)
-			ret = clk->ops->enable(clk);
-	}
-	clk->usage_count++;
+	ret = do_clk_enable(clk);
 	spin_unlock_irqrestore(&clocks_lock, flags);
-
 	return ret;
 }
 EXPORT_SYMBOL(clk_enable);
@@ -108,17 +195,8 @@ void clk_disable(struct clk *clk)
 {
 	unsigned long flags;
 
-	if (!clk || IS_ERR(clk))
-		return;
-
-	WARN_ON(clk->usage_count == 0);
-
 	spin_lock_irqsave(&clocks_lock, flags);
-	clk->usage_count--;
-	if (clk->usage_count == 0) {
-		if (clk->ops && clk->ops->disable)
-			clk->ops->disable(clk);
-	}
+	do_clk_disable(clk);
 	spin_unlock_irqrestore(&clocks_lock, flags);
 }
 EXPORT_SYMBOL(clk_disable);
@@ -152,15 +230,14 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
 	int i, found = 0, val = 0;
 	unsigned long flags;
 
-	if (!clk || IS_ERR(clk) || !parent || IS_ERR(parent))
+	if (!clk || !parent)
 		return -EFAULT;
-	if (clk->usage_count)
-		return -EBUSY;
-	if (!clk->pclk_sel)
-		return -EPERM;
 	if (clk->pclk == parent)
 		return 0;
+	if (!clk->pclk_sel)
+		return -EPERM;
 
+	/* check if requested parent is in clk parent list */
 	for (i = 0; i < clk->pclk_sel->pclk_count; i++) {
 		if (clk->pclk_sel->pclk_info[i].pclk == parent) {
 			found = 1;
@@ -175,13 +252,14 @@ int clk_set_parent(struct clk *clk, struct clk *parent)
 	/* reflect parent change in hardware */
 	val = readl(clk->pclk_sel->pclk_sel_reg);
 	val &= ~(clk->pclk_sel->pclk_sel_mask << clk->pclk_sel_shift);
-	val |= clk->pclk_sel->pclk_info[i].pclk_mask << clk->pclk_sel_shift;
+	val |= clk->pclk_sel->pclk_info[i].pclk_val << clk->pclk_sel_shift;
 	writel(val, clk->pclk_sel->pclk_sel_reg);
 	spin_unlock_irqrestore(&clocks_lock, flags);
 
 	/* reflect parent change in software */
-	clk->recalc(clk);
-	propagate_rate(&clk->children);
+	clk_reparent(clk, &clk->pclk_sel->pclk_info[i]);
+
+	propagate_rate(clk, 0);
 	return 0;
 }
 EXPORT_SYMBOL(clk_set_parent);
@@ -195,19 +273,37 @@ EXPORT_SYMBOL(clk_set_parent);
  */
 int clk_set_rate(struct clk *clk, unsigned long rate)
 {
-	/* TODO */
-	return -EINVAL;
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	if (!clk || !rate)
+		return -EFAULT;
+
+	if (clk->set_rate) {
+		spin_lock_irqsave(&clocks_lock, flags);
+		ret = clk->set_rate(clk, rate);
+		if (!ret)
+			/* if successful -> propagate */
+			propagate_rate(clk, 0);
+		spin_unlock_irqrestore(&clocks_lock, flags);
+	} else if (clk->pclk) {
+		u32 mult = clk->div_factor ? clk->div_factor : 1;
+		ret = clk_set_rate(clk->pclk, mult * rate);
+	}
+
+	return ret;
 }
 EXPORT_SYMBOL(clk_set_rate);
 
 /* registers clock in platform clock framework */
 void clk_register(struct clk_lookup *cl)
 {
-	struct clk *clk = cl->clk;
+	struct clk *clk;
 	unsigned long flags;
 
-	if (!clk || IS_ERR(clk))
+	if (!cl || !cl->clk)
 		return;
+	clk = cl->clk;
 
 	spin_lock_irqsave(&clocks_lock, flags);
 
@@ -220,15 +316,24 @@ void clk_register(struct clk_lookup *cl)
 	/* root clock don't have any parents */
 	if (!clk->pclk && !clk->pclk_sel) {
 		list_add(&clk->sibling, &root_clks);
-		/* add clocks with only one parent to parent's children list */
 	} else if (clk->pclk && !clk->pclk_sel) {
+		/* add clocks with only one parent to parent's children list */
 		list_add(&clk->sibling, &clk->pclk->children);
 	} else {
-		/* add clocks with > 1 parent to 1st parent's children list */
-		clk->pclk = clk->pclk_sel->pclk_info[0].pclk;
-		list_add(&clk->sibling,
-			 &clk->pclk_sel->pclk_info[0].pclk->children);
+		/* clocks with more than one parent */
+		struct pclk_info *pclk_info;
+
+		pclk_info = pclk_info_get(clk);
+		if (!pclk_info) {
+			pr_err("CLKDEV: invalid pclk info of clk with"
+					" %s dev_id and %s con_id\n",
+					cl->dev_id, cl->con_id);
+		} else {
+			clk->pclk = pclk_info->pclk;
+			list_add(&clk->sibling, &pclk_info->pclk->children);
+		}
 	}
+
 	spin_unlock_irqrestore(&clocks_lock, flags);
 
 	/* add clock to arm clockdev framework */
@@ -236,56 +341,142 @@ void clk_register(struct clk_lookup *cl)
 }
 
 /**
- * propagate_rate - recalculate and propagate all clocks in list head
+ * propagate_rate - recalculate and propagate all clocks to children
+ * @pclk: parent clock required to be propogated
+ * @on_init: flag for enabling clocks which are ENABLED_ON_INIT.
  *
- * Recalculates all root clocks in list head, which if the clock's .recalc is
- * set correctly, should also propagate their rates.
+ * Recalculates all children clocks
  */
-static void propagate_rate(struct list_head *lhead)
+void propagate_rate(struct clk *pclk, int on_init)
 {
-	struct clk *clkp, *_temp;
+	struct clk *clk, *_temp;
+	int ret = 0;
+
+	list_for_each_entry_safe(clk, _temp, &pclk->children, sibling) {
+		if (clk->recalc) {
+			ret = clk->recalc(clk);
+			/*
+			 * recalc will return error if clk out is not programmed
+			 * In this case configure default rate.
+			 */
+			if (ret && clk->set_rate)
+				clk->set_rate(clk, 0);
+		}
+		propagate_rate(clk, on_init);
+
+		if (!on_init)
+			continue;
 
-	list_for_each_entry_safe(clkp, _temp, lhead, sibling) {
-		if (clkp->recalc)
-			clkp->recalc(clkp);
-		propagate_rate(&clkp->children);
+		/* Enable clks enabled on init, in software view */
+		if (clk->flags & ENABLED_ON_INIT)
+			do_clk_enable(clk);
 	}
 }
 
-/* returns current programmed clocks clock info structure */
-static struct pclk_info *pclk_info_get(struct clk *clk)
+/**
+ * round_rate_index - return closest programmable rate index in rate_config tbl
+ * @clk: ptr to clock structure
+ * @drate: desired rate
+ * @rate: final rate will be returned in this variable only.
+ *
+ * Finds index in rate_config for highest clk rate which is less than
+ * requested rate. If there is no clk rate lesser than requested rate then
+ * -EINVAL is returned. This routine assumes that rate_config is written
+ * in incrementing order of clk rates.
+ * If drate passed is zero then default rate is programmed.
+ */
+static int
+round_rate_index(struct clk *clk, unsigned long drate, unsigned long *rate)
 {
-	unsigned int mask, i;
-	unsigned long flags;
-	struct pclk_info *info = NULL;
+	unsigned long tmp = 0, prev_rate = 0;
+	int index;
 
-	spin_lock_irqsave(&clocks_lock, flags);
-	mask = (readl(clk->pclk_sel->pclk_sel_reg) >> clk->pclk_sel_shift)
-			& clk->pclk_sel->pclk_sel_mask;
+	if (!clk->calc_rate)
+		return -EFAULT;
 
-	for (i = 0; i < clk->pclk_sel->pclk_count; i++) {
-		if (clk->pclk_sel->pclk_info[i].pclk_mask == mask)
-			info = &clk->pclk_sel->pclk_info[i];
+	if (!drate)
+		return -EINVAL;
+
+	/*
+	 * This loops ends on two conditions:
+	 * - as soon as clk is found with rate greater than requested rate.
+	 * - if all clks in rate_config are smaller than requested rate.
+	 */
+	for (index = 0; index < clk->rate_config.count; index++) {
+		prev_rate = tmp;
+		tmp = clk->calc_rate(clk, index);
+		if (drate < tmp) {
+			index--;
+			break;
+		}
 	}
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	/* return if can't find suitable clock */
+	if (index < 0) {
+		index = -EINVAL;
+		*rate = 0;
+	} else if (index == clk->rate_config.count) {
+		/* program with highest clk rate possible */
+		index = clk->rate_config.count - 1;
+		*rate = tmp;
+	} else
+		*rate = prev_rate;
 
-	return info;
+	return index;
 }
 
-/*
- * Set pclk as cclk's parent and add clock sibling node to current parents
- * children list
+/**
+ * clk_round_rate - adjust a rate to the exact rate a clock can provide
+ * @clk: clock source
+ * @rate: desired clock rate in Hz
+ *
+ * Returns rounded clock rate in Hz, or negative errno.
  */
-static void change_parent(struct clk *cclk, struct clk *pclk)
+long clk_round_rate(struct clk *clk, unsigned long drate)
 {
-	unsigned long flags;
+	long rate = 0;
+	int index;
+
+	/*
+	 * propagate call to parent who supports calc_rate. Similar approach is
+	 * used in clk_set_rate.
+	 */
+	if (!clk->calc_rate) {
+		u32 mult;
+		if (!clk->pclk)
+			return clk->rate;
+
+		mult = clk->div_factor ? clk->div_factor : 1;
+		return clk_round_rate(clk->pclk, mult * drate) / mult;
+	}
 
-	spin_lock_irqsave(&clocks_lock, flags);
-	list_del(&cclk->sibling);
-	list_add(&cclk->sibling, &pclk->children);
+	index = round_rate_index(clk, drate, &rate);
+	if (index >= 0)
+		return rate;
+	else
+		return index;
+}
+EXPORT_SYMBOL(clk_round_rate);
 
-	cclk->pclk = pclk;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+/*All below functions are called with lock held */
+
+/*
+ * Calculates pll clk rate for specific value of mode, m, n and p
+ *
+ * In normal mode
+ * rate = (2 * M[15:8] * Fin)/(N * 2^P)
+ *
+ * In Dithered mode
+ * rate = (2 * M[15:0] * Fin)/(256 * N * 2^P)
+ */
+unsigned long pll_calc_rate(struct clk *clk, int index)
+{
+	unsigned long rate = clk->pclk->rate;
+	struct pll_rate_tbl *tbls = clk->rate_config.tbls;
+	unsigned int mode;
+
+	mode = tbls[index].mode ? 256 : 1;
+	return (((2 * rate / 10000) * tbls[index].m) /
+			(mode * tbls[index].n * (1 << tbls[index].p))) * 10000;
 }
 
 /*
@@ -297,13 +488,11 @@ static void change_parent(struct clk *cclk, struct clk *pclk)
  * In Dithered mode
  * rate = (2 * M[15:0] * Fin)/(256 * N * 2^P)
  */
-void pll_clk_recalc(struct clk *clk)
+int pll_clk_recalc(struct clk *clk)
 {
 	struct pll_clk_config *config = clk->private_data;
 	unsigned int num = 2, den = 0, val, mode = 0;
-	unsigned long flags;
 
-	spin_lock_irqsave(&clocks_lock, flags);
 	mode = (readl(config->mode_reg) >> config->masks->mode_shift) &
 		config->masks->mode_mask;
 
@@ -325,22 +514,120 @@ void pll_clk_recalc(struct clk *clk)
 		den *= 256;
 	}
 
+	if (!den)
+		return -EINVAL;
+
 	clk->rate = (((clk->pclk->rate/10000) * num) / den) * 10000;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
+}
+
+/*
+ * Configures new clock rate of pll
+ */
+int pll_clk_set_rate(struct clk *clk, unsigned long desired_rate)
+{
+	struct pll_rate_tbl *tbls = clk->rate_config.tbls;
+	struct pll_clk_config *config = clk->private_data;
+	unsigned long val, rate;
+	int i;
+
+	i = round_rate_index(clk, desired_rate, &rate);
+	if (i < 0)
+		return i;
+
+	val = readl(config->mode_reg) &
+		~(config->masks->mode_mask << config->masks->mode_shift);
+	val |= (tbls[i].mode & config->masks->mode_mask) <<
+		config->masks->mode_shift;
+	writel(val, config->mode_reg);
+
+	val = readl(config->cfg_reg) &
+		~(config->masks->div_p_mask << config->masks->div_p_shift);
+	val |= (tbls[i].p & config->masks->div_p_mask) <<
+		config->masks->div_p_shift;
+	val &= ~(config->masks->div_n_mask << config->masks->div_n_shift);
+	val |= (tbls[i].n & config->masks->div_n_mask) <<
+		config->masks->div_n_shift;
+	val &= ~(config->masks->dith_fdbk_m_mask <<
+			config->masks->dith_fdbk_m_shift);
+	if (tbls[i].mode)
+		val |= (tbls[i].m & config->masks->dith_fdbk_m_mask) <<
+			config->masks->dith_fdbk_m_shift;
+	else
+		val |= (tbls[i].m & config->masks->norm_fdbk_m_mask) <<
+			config->masks->norm_fdbk_m_shift;
+
+	writel(val, config->cfg_reg);
+
+	clk->rate = rate;
+
+	return 0;
+}
+
+/*
+ * Calculates ahb, apb clk rate for specific value of div
+ */
+unsigned long bus_calc_rate(struct clk *clk, int index)
+{
+	unsigned long rate = clk->pclk->rate;
+	struct bus_rate_tbl *tbls = clk->rate_config.tbls;
+
+	return rate / (tbls[index].div + 1);
 }
 
 /* calculates current programmed rate of ahb or apb bus */
-void bus_clk_recalc(struct clk *clk)
+int bus_clk_recalc(struct clk *clk)
 {
 	struct bus_clk_config *config = clk->private_data;
 	unsigned int div;
-	unsigned long flags;
 
-	spin_lock_irqsave(&clocks_lock, flags);
 	div = ((readl(config->reg) >> config->masks->shift) &
 			config->masks->mask) + 1;
+
+	if (!div)
+		return -EINVAL;
+
 	clk->rate = (unsigned long)clk->pclk->rate / div;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
+}
+
+/* Configures new clock rate of AHB OR APB bus */
+int bus_clk_set_rate(struct clk *clk, unsigned long desired_rate)
+{
+	struct bus_rate_tbl *tbls = clk->rate_config.tbls;
+	struct bus_clk_config *config = clk->private_data;
+	unsigned long val, rate;
+	int i;
+
+	i = round_rate_index(clk, desired_rate, &rate);
+	if (i < 0)
+		return i;
+
+	val = readl(config->reg) &
+		~(config->masks->mask << config->masks->shift);
+	val |= (tbls[i].div & config->masks->mask) << config->masks->shift;
+	writel(val, config->reg);
+
+	clk->rate = rate;
+
+	return 0;
+}
+
+/*
+ * gives rate for different values of eq, x and y
+ *
+ * Fout from synthesizer can be given from two equations:
+ * Fout1 = (Fin * X/Y)/2		EQ1
+ * Fout2 = Fin * X/Y			EQ2
+ */
+unsigned long aux_calc_rate(struct clk *clk, int index)
+{
+	unsigned long rate = clk->pclk->rate;
+	struct aux_rate_tbl *tbls = clk->rate_config.tbls;
+	u8 eq = tbls[index].eq ? 1 : 2;
+
+	return (((rate/10000) * tbls[index].xscale) /
+			(tbls[index].yscale * eq)) * 10000;
 }
 
 /*
@@ -353,47 +640,76 @@ void bus_clk_recalc(struct clk *clk)
  *
  * Selection of eqn 1 or 2 is programmed in register
  */
-void aux_clk_recalc(struct clk *clk)
+int aux_clk_recalc(struct clk *clk)
 {
 	struct aux_clk_config *config = clk->private_data;
-	struct pclk_info *pclk_info = NULL;
 	unsigned int num = 1, den = 1, val, eqn;
-	unsigned long flags;
 
-	/* get current programmed parent */
-	pclk_info = pclk_info_get(clk);
-	if (!pclk_info) {
-		spin_lock_irqsave(&clocks_lock, flags);
-		clk->pclk = NULL;
-		clk->rate = 0;
-		spin_unlock_irqrestore(&clocks_lock, flags);
-		return;
-	}
+	val = readl(config->synth_reg);
 
-	change_parent(clk, pclk_info->pclk);
+	eqn = (val >> config->masks->eq_sel_shift) &
+		config->masks->eq_sel_mask;
+	if (eqn == config->masks->eq1_mask)
+		den *= 2;
 
-	spin_lock_irqsave(&clocks_lock, flags);
-	if (pclk_info->scalable) {
-		val = readl(config->synth_reg);
-
-		eqn = (val >> config->masks->eq_sel_shift) &
-			config->masks->eq_sel_mask;
-		if (eqn == config->masks->eq1_mask)
-			den *= 2;
-
-		/* calculate numerator */
-		num = (val >> config->masks->xscale_sel_shift) &
-			config->masks->xscale_sel_mask;
-
-		/* calculate denominator */
-		den *= (val >> config->masks->yscale_sel_shift) &
-			config->masks->yscale_sel_mask;
-		val = (((clk->pclk->rate/10000) * num) / den) * 10000;
-	} else
-		val = clk->pclk->rate;
+	/* calculate numerator */
+	num = (val >> config->masks->xscale_sel_shift) &
+		config->masks->xscale_sel_mask;
 
-	clk->rate = val;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	/* calculate denominator */
+	den *= (val >> config->masks->yscale_sel_shift) &
+		config->masks->yscale_sel_mask;
+
+	if (!den)
+		return -EINVAL;
+
+	clk->rate = (((clk->pclk->rate/10000) * num) / den) * 10000;
+	return 0;
+}
+
+/* Configures new clock rate of auxiliary synthesizers used by: UART, FIRDA*/
+int aux_clk_set_rate(struct clk *clk, unsigned long desired_rate)
+{
+	struct aux_rate_tbl *tbls = clk->rate_config.tbls;
+	struct aux_clk_config *config = clk->private_data;
+	unsigned long val, rate;
+	int i;
+
+	i = round_rate_index(clk, desired_rate, &rate);
+	if (i < 0)
+		return i;
+
+	val = readl(config->synth_reg) &
+		~(config->masks->eq_sel_mask << config->masks->eq_sel_shift);
+	val |= (tbls[i].eq & config->masks->eq_sel_mask) <<
+		config->masks->eq_sel_shift;
+	val &= ~(config->masks->xscale_sel_mask <<
+			config->masks->xscale_sel_shift);
+	val |= (tbls[i].xscale & config->masks->xscale_sel_mask) <<
+		config->masks->xscale_sel_shift;
+	val &= ~(config->masks->yscale_sel_mask <<
+			config->masks->yscale_sel_shift);
+	val |= (tbls[i].yscale & config->masks->yscale_sel_mask) <<
+		config->masks->yscale_sel_shift;
+	writel(val, config->synth_reg);
+
+	clk->rate = rate;
+
+	return 0;
+}
+
+/*
+ * Calculates gpt clk rate for different values of mscale and nscale
+ *
+ * Fout= Fin/((2 ^ (N+1)) * (M+1))
+ */
+unsigned long gpt_calc_rate(struct clk *clk, int index)
+{
+	unsigned long rate = clk->pclk->rate;
+	struct gpt_rate_tbl *tbls = clk->rate_config.tbls;
+
+	return rate / ((1 << (tbls[index].nscale + 1)) *
+			(tbls[index].mscale + 1));
 }
 
 /*
@@ -401,49 +717,142 @@ void aux_clk_recalc(struct clk *clk)
  * Fout from synthesizer can be given from below equations:
  * Fout= Fin/((2 ^ (N+1)) * (M+1))
  */
-void gpt_clk_recalc(struct clk *clk)
+int gpt_clk_recalc(struct clk *clk)
 {
 	struct gpt_clk_config *config = clk->private_data;
-	struct pclk_info *pclk_info = NULL;
 	unsigned int div = 1, val;
-	unsigned long flags;
 
-	pclk_info = pclk_info_get(clk);
-	if (!pclk_info) {
-		spin_lock_irqsave(&clocks_lock, flags);
-		clk->pclk = NULL;
-		clk->rate = 0;
-		spin_unlock_irqrestore(&clocks_lock, flags);
-		return;
-	}
+	val = readl(config->synth_reg);
+	div += (val >> config->masks->mscale_sel_shift) &
+		config->masks->mscale_sel_mask;
+	div *= 1 << (((val >> config->masks->nscale_sel_shift) &
+				config->masks->nscale_sel_mask) + 1);
 
-	change_parent(clk, pclk_info->pclk);
-
-	spin_lock_irqsave(&clocks_lock, flags);
-	if (pclk_info->scalable) {
-		val = readl(config->synth_reg);
-		div += (val >> config->masks->mscale_sel_shift) &
-			config->masks->mscale_sel_mask;
-		div *= 1 << (((val >> config->masks->nscale_sel_shift) &
-					config->masks->nscale_sel_mask) + 1);
-	}
+	if (!div)
+		return -EINVAL;
 
 	clk->rate = (unsigned long)clk->pclk->rate / div;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
+}
+
+/* Configures new clock rate of gptiliary synthesizers used by: UART, FIRDA*/
+int gpt_clk_set_rate(struct clk *clk, unsigned long desired_rate)
+{
+	struct gpt_rate_tbl *tbls = clk->rate_config.tbls;
+	struct gpt_clk_config *config = clk->private_data;
+	unsigned long val, rate;
+	int i;
+
+	i = round_rate_index(clk, desired_rate, &rate);
+	if (i < 0)
+		return i;
+
+	val = readl(config->synth_reg) & ~(config->masks->mscale_sel_mask <<
+			config->masks->mscale_sel_shift);
+	val |= (tbls[i].mscale & config->masks->mscale_sel_mask) <<
+		config->masks->mscale_sel_shift;
+	val &= ~(config->masks->nscale_sel_mask <<
+			config->masks->nscale_sel_shift);
+	val |= (tbls[i].nscale & config->masks->nscale_sel_mask) <<
+		config->masks->nscale_sel_shift;
+	writel(val, config->synth_reg);
+
+	clk->rate = rate;
+
+	return 0;
+}
+
+/*
+ * Calculates clcd clk rate for different values of div
+ *
+ * Fout from synthesizer can be given from below equation:
+ * Fout= Fin/2*div (division factor)
+ * div is 17 bits:-
+ *	0-13 (fractional part)
+ *	14-16 (integer part)
+ * To calculate Fout we left shift val by 14 bits and divide Fin by
+ * complete div (including fractional part) and then right shift the
+ * result by 14 places.
+ */
+unsigned long clcd_calc_rate(struct clk *clk, int index)
+{
+	unsigned long rate = clk->pclk->rate;
+	struct clcd_rate_tbl *tbls = clk->rate_config.tbls;
+
+	rate /= 1000;
+	rate <<= 12;
+	rate /= (2 * tbls[index].div);
+	rate >>= 12;
+	rate *= 1000;
+
+	return rate;
+}
+
+/*
+ * calculates current programmed rate of clcd synthesizer
+ * Fout from synthesizer can be given from below equation:
+ * Fout= Fin/2*div (division factor)
+ * div is 17 bits:-
+ *	0-13 (fractional part)
+ *	14-16 (integer part)
+ * To calculate Fout we left shift val by 14 bits and divide Fin by
+ * complete div (including fractional part) and then right shift the
+ * result by 14 places.
+ */
+int clcd_clk_recalc(struct clk *clk)
+{
+	struct clcd_clk_config *config = clk->private_data;
+	unsigned int div = 1;
+	unsigned long prate;
+	unsigned int val;
+
+	val = readl(config->synth_reg);
+	div = (val >> config->masks->div_factor_shift) &
+		config->masks->div_factor_mask;
+
+	if (!div)
+		return -EINVAL;
+
+	prate = clk->pclk->rate / 1000; /* first level division, make it KHz */
+
+	clk->rate = (((unsigned long)prate << 12) / (2 * div)) >> 12;
+	clk->rate *= 1000;
+	return 0;
+}
+
+/* Configures new clock rate of auxiliary synthesizers used by: UART, FIRDA*/
+int clcd_clk_set_rate(struct clk *clk, unsigned long desired_rate)
+{
+	struct clcd_rate_tbl *tbls = clk->rate_config.tbls;
+	struct clcd_clk_config *config = clk->private_data;
+	unsigned long val, rate;
+	int i;
+
+	i = round_rate_index(clk, desired_rate, &rate);
+	if (i < 0)
+		return i;
+
+	val = readl(config->synth_reg) & ~(config->masks->div_factor_mask <<
+			config->masks->div_factor_shift);
+	val |= (tbls[i].div & config->masks->div_factor_mask) <<
+		config->masks->div_factor_shift;
+	writel(val, config->synth_reg);
+
+	clk->rate = rate;
+
+	return 0;
 }
 
 /*
  * Used for clocks that always have value as the parent clock divided by a
  * fixed divisor
  */
-void follow_parent(struct clk *clk)
+int follow_parent(struct clk *clk)
 {
-	unsigned long flags;
 	unsigned int div_factor = (clk->div_factor < 1) ? 1 : clk->div_factor;
 
-	spin_lock_irqsave(&clocks_lock, flags);
 	clk->rate = clk->pclk->rate/div_factor;
-	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
 }
 
 /**
@@ -454,5 +863,25 @@ void follow_parent(struct clk *clk)
  */
 void recalc_root_clocks(void)
 {
-	propagate_rate(&root_clks);
+	struct clk *pclk;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	list_for_each_entry(pclk, &root_clks, sibling) {
+		if (pclk->recalc) {
+			ret = pclk->recalc(pclk);
+			/*
+			 * recalc will return error if clk out is not programmed
+			 * In this case configure default clock.
+			 */
+			if (ret && pclk->set_rate)
+				pclk->set_rate(pclk, 0);
+		}
+		propagate_rate(pclk, 1);
+		/* Enable clks enabled on init, in software view */
+		if (pclk->flags & ENABLED_ON_INIT)
+			do_clk_enable(pclk);
+	}
+	spin_unlock_irqrestore(&clocks_lock, flags);
 }
diff --git a/arch/arm/plat-spear/include/plat/clock.h b/arch/arm/plat-spear/include/plat/clock.h
index 863d9e98392..5a601d83097 100644
--- a/arch/arm/plat-spear/include/plat/clock.h
+++ b/arch/arm/plat-spear/include/plat/clock.h
@@ -21,6 +21,7 @@
 /* clk structure flags */
 #define	ALWAYS_ENABLED		(1 << 0) /* clock always enabled */
 #define	RESET_TO_ENABLE		(1 << 1) /* reset register bit to enable clk */
+#define	ENABLED_ON_INIT		(1 << 2) /* clocks enabled at init */
 
 /**
  * struct clkops - clock operations
@@ -35,13 +36,11 @@ struct clkops {
 /**
  * struct pclk_info - parents info
  * @pclk: pointer to parent clk
- * @pclk_mask: value to be written for selecting this parent
- * @scalable: Is parent scalable (1 - YES, 0 - NO)
+ * @pclk_val: value to be written for selecting this parent
  */
 struct pclk_info {
 	struct clk *pclk;
-	u8 pclk_mask;
-	u8 scalable;
+	u8 pclk_val;
 };
 
 /**
@@ -59,6 +58,18 @@ struct pclk_sel {
 };
 
 /**
+ * struct rate_config - clk rate configurations
+ * @tbls: array of device specific clk rate tables, in ascending order of rates
+ * @count: size of tbls array
+ * @default_index: default setting when originally disabled
+ */
+struct rate_config {
+	void *tbls;
+	u8 count;
+	u8 default_index;
+};
+
+/**
  * struct clk - clock structure
  * @usage_count: num of users who enabled this clock
  * @flags: flags for clock properties
@@ -67,7 +78,10 @@ struct pclk_sel {
  * @en_reg_bit: clk enable/disable bit
  * @ops: clk enable/disable ops - generic_clkops selected if NULL
  * @recalc: pointer to clock rate recalculate function
- * @div_factor: division factor to parent clock. Only for recalc = follow_parent
+ * @set_rate: pointer to clock set rate function
+ * @calc_rate: pointer to clock get rate function for index
+ * @rate_config: rate configuration information, used by set_rate
+ * @div_factor: division factor to parent clock.
  * @pclk: current parent clk
  * @pclk_sel: pointer to parent selection structure
  * @pclk_sel_shift: register shift for selecting parent of this clock
@@ -82,7 +96,10 @@ struct clk {
 	void __iomem *en_reg;
 	u8 en_reg_bit;
 	const struct clkops *ops;
-	void (*recalc) (struct clk *);
+	int (*recalc) (struct clk *);
+	int (*set_rate) (struct clk *, unsigned long rate);
+	unsigned long (*calc_rate)(struct clk *, int index);
+	struct rate_config rate_config;
 	unsigned int div_factor;
 
 	struct clk *pclk;
@@ -115,6 +132,14 @@ struct pll_clk_config {
 	struct pll_clk_masks *masks;
 };
 
+/* pll clk rate config structure */
+struct pll_rate_tbl {
+	u8 mode;
+	u16 m;
+	u8 n;
+	u8 p;
+};
+
 /* ahb and apb bus configuration structure */
 struct bus_clk_masks {
 	u32 mask;
@@ -126,6 +151,11 @@ struct bus_clk_config {
 	struct bus_clk_masks *masks;
 };
 
+/* ahb and apb clk bus rate config structure */
+struct bus_rate_tbl {
+	u8 div;
+};
+
 /* Aux clk configuration structure: applicable to UART and FIRDA */
 struct aux_clk_masks {
 	u32 eq_sel_mask;
@@ -143,6 +173,13 @@ struct aux_clk_config {
 	struct aux_clk_masks *masks;
 };
 
+/* aux clk rate config structure */
+struct aux_rate_tbl {
+	u16 xscale;
+	u16 yscale;
+	u8 eq;
+};
+
 /* GPT clk configuration structure */
 struct gpt_clk_masks {
 	u32 mscale_sel_mask;
@@ -156,15 +193,48 @@ struct gpt_clk_config {
 	struct gpt_clk_masks *masks;
 };
 
+/* gpt clk rate config structure */
+struct gpt_rate_tbl {
+	u16 mscale;
+	u16 nscale;
+};
+
+/* clcd clk configuration structure */
+struct clcd_synth_masks {
+	u32 div_factor_mask;
+	u32 div_factor_shift;
+};
+
+struct clcd_clk_config {
+	void __iomem *synth_reg;
+	struct clcd_synth_masks *masks;
+};
+
+/* clcd clk rate config structure */
+struct clcd_rate_tbl {
+	u16 div;
+};
+
 /* platform specific clock functions */
 void clk_register(struct clk_lookup *cl);
 void recalc_root_clocks(void);
 
-/* clock recalc functions */
-void follow_parent(struct clk *clk);
-void pll_clk_recalc(struct clk *clk);
-void bus_clk_recalc(struct clk *clk);
-void gpt_clk_recalc(struct clk *clk);
-void aux_clk_recalc(struct clk *clk);
+/* clock recalc & set rate functions */
+int follow_parent(struct clk *clk);
+unsigned long pll_calc_rate(struct clk *clk, int index);
+int pll_clk_recalc(struct clk *clk);
+int pll_clk_set_rate(struct clk *clk, unsigned long desired_rate);
+unsigned long bus_calc_rate(struct clk *clk, int index);
+int bus_clk_recalc(struct clk *clk);
+int bus_clk_set_rate(struct clk *clk, unsigned long desired_rate);
+unsigned long gpt_calc_rate(struct clk *clk, int index);
+int gpt_clk_recalc(struct clk *clk);
+int gpt_clk_set_rate(struct clk *clk, unsigned long desired_rate);
+unsigned long aux_calc_rate(struct clk *clk, int index);
+int aux_clk_recalc(struct clk *clk);
+int aux_clk_set_rate(struct clk *clk, unsigned long desired_rate);
+unsigned long clcd_calc_rate(struct clk *clk, int index);
+int clcd_clk_recalc(struct clk *clk);
+int clcd_clk_set_rate(struct clk *clk, unsigned long desired_rate);
 
 #endif /* __PLAT_CLOCK_H */