8 files changed, 233 insertions, 92 deletions

diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 4998aee59267..89a48a7bd5df 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -9,3 +9,4 @@ obj-y += clk-system.o clk-peripheral.o clk-programmable.o
 obj-$(CONFIG_HAVE_AT91_UTMI)		+= clk-utmi.o
 obj-$(CONFIG_HAVE_AT91_USB_CLK)		+= clk-usb.o
 obj-$(CONFIG_HAVE_AT91_SMD)		+= clk-smd.o
+obj-$(CONFIG_HAVE_AT91_H32MX)		+= clk-h32mx.o
diff --git a/drivers/clk/at91/clk-h32mx.c b/drivers/clk/at91/clk-h32mx.c
new file mode 100644
index 000000000000..152dcb3f7b5f
--- /dev/null
+++ b/drivers/clk/at91/clk-h32mx.c
@@ -0,0 +1,123 @@
+/*
+ * clk-h32mx.c
+ *
+ *  Copyright (C) 2014 Atmel
+ *
+ * Alexandre Belloni <alexandre.belloni@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#include "pmc.h"
+
+#define H32MX_MAX_FREQ	90000000
+
+struct clk_sama5d4_h32mx {
+	struct clk_hw hw;
+	struct at91_pmc *pmc;
+};
+
+#define to_clk_sama5d4_h32mx(hw) container_of(hw, struct clk_sama5d4_h32mx, hw)
+
+static unsigned long clk_sama5d4_h32mx_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct clk_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw);
+
+	if (pmc_read(h32mxclk->pmc, AT91_PMC_MCKR) & AT91_PMC_H32MXDIV)
+		return parent_rate / 2;
+
+	if (parent_rate > H32MX_MAX_FREQ)
+		pr_warn("H32MX clock is too fast\n");
+	return parent_rate;
+}
+
+static long clk_sama5d4_h32mx_round_rate(struct clk_hw *hw, unsigned long rate,
+				       unsigned long *parent_rate)
+{
+	unsigned long div;
+
+	if (rate > *parent_rate)
+		return *parent_rate;
+	div = *parent_rate / 2;
+	if (rate < div)
+		return div;
+
+	if (rate - div < *parent_rate - rate)
+		return div;
+
+	return *parent_rate;
+}
+
+static int clk_sama5d4_h32mx_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct clk_sama5d4_h32mx *h32mxclk = to_clk_sama5d4_h32mx(hw);
+	struct at91_pmc *pmc = h32mxclk->pmc;
+	u32 tmp;
+
+	if (parent_rate != rate && (parent_rate / 2) != rate)
+		return -EINVAL;
+
+	pmc_lock(pmc);
+	tmp = pmc_read(pmc, AT91_PMC_MCKR) & ~AT91_PMC_H32MXDIV;
+	if ((parent_rate / 2) == rate)
+		tmp |= AT91_PMC_H32MXDIV;
+	pmc_write(pmc, AT91_PMC_MCKR, tmp);
+	pmc_unlock(pmc);
+
+	return 0;
+}
+
+static const struct clk_ops h32mx_ops = {
+	.recalc_rate = clk_sama5d4_h32mx_recalc_rate,
+	.round_rate = clk_sama5d4_h32mx_round_rate,
+	.set_rate = clk_sama5d4_h32mx_set_rate,
+};
+
+void __init of_sama5d4_clk_h32mx_setup(struct device_node *np,
+				     struct at91_pmc *pmc)
+{
+	struct clk_sama5d4_h32mx *h32mxclk;
+	struct clk_init_data init;
+	const char *parent_name;
+	struct clk *clk;
+
+	h32mxclk = kzalloc(sizeof(*h32mxclk), GFP_KERNEL);
+	if (!h32mxclk)
+		return;
+
+	parent_name = of_clk_get_parent_name(np, 0);
+
+	init.name = np->name;
+	init.ops = &h32mx_ops;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+	init.flags = CLK_SET_RATE_GATE;
+
+	h32mxclk->hw.init = &init;
+	h32mxclk->pmc = pmc;
+
+	clk = clk_register(NULL, &h32mxclk->hw);
+	if (!clk)
+		return;
+
+	of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
diff --git a/drivers/clk/at91/clk-pll.c b/drivers/clk/at91/clk-pll.c
index cf6ed023504c..6ec79dbc0840 100644
--- a/drivers/clk/at91/clk-pll.c
+++ b/drivers/clk/at91/clk-pll.c
@@ -15,6 +15,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/io.h>
+#include <linux/kernel.h>
 #include <linux/wait.h>
 #include <linux/sched.h>
 #include <linux/interrupt.h>
@@ -29,9 +30,12 @@
 #define PLL_DIV(reg)		((reg) & PLL_DIV_MASK)
 #define PLL_MUL(reg, layout)	(((reg) >> (layout)->mul_shift) & \
 				 (layout)->mul_mask)
+#define PLL_MUL_MIN		2
+#define PLL_MUL_MASK(layout)	((layout)->mul_mask)
+#define PLL_MUL_MAX(layout)	(PLL_MUL_MASK(layout) + 1)
 #define PLL_ICPR_SHIFT(id)	((id) * 16)
 #define PLL_ICPR_MASK(id)	(0xffff << PLL_ICPR_SHIFT(id))
-#define PLL_MAX_COUNT		0x3ff
+#define PLL_MAX_COUNT		0x3f
 #define PLL_COUNT_SHIFT		8
 #define PLL_OUT_SHIFT		14
 #define PLL_MAX_ID		1
@@ -147,115 +151,113 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
 					 unsigned long parent_rate)
 {
 	struct clk_pll *pll = to_clk_pll(hw);
-	const struct clk_pll_layout *layout = pll->layout;
-	struct at91_pmc *pmc = pll->pmc;
-	int offset = PLL_REG(pll->id);
-	u32 tmp = pmc_read(pmc, offset) & layout->pllr_mask;
-	u8 div = PLL_DIV(tmp);
-	u16 mul = PLL_MUL(tmp, layout);
-	if (!div || !mul)
+
+	if (!pll->div || !pll->mul)
 		return 0;
 
-	return (parent_rate * (mul + 1)) / div;
+	return (parent_rate / pll->div) * (pll->mul + 1);
 }
 
 static long clk_pll_get_best_div_mul(struct clk_pll *pll, unsigned long rate,
 				     unsigned long parent_rate,
 				     u32 *div, u32 *mul,
 				     u32 *index) {
-	unsigned long maxrate;
-	unsigned long minrate;
-	unsigned long divrate;
-	unsigned long bestdiv = 1;
-	unsigned long bestmul;
-	unsigned long tmpdiv;
-	unsigned long roundup;
-	unsigned long rounddown;
-	unsigned long remainder;
-	unsigned long bestremainder;
-	unsigned long maxmul;
-	unsigned long maxdiv;
-	unsigned long mindiv;
-	int i = 0;
 	const struct clk_pll_layout *layout = pll->layout;
 	const struct clk_pll_characteristics *characteristics =
 							pll->characteristics;
+	unsigned long bestremainder = ULONG_MAX;
+	unsigned long maxdiv, mindiv, tmpdiv;
+	long bestrate = -ERANGE;
+	unsigned long bestdiv;
+	unsigned long bestmul;
+	int i = 0;
 
-	/* Minimum divider = 1 */
-	/* Maximum multiplier = max_mul */
-	maxmul = layout->mul_mask + 1;
-	maxrate = (parent_rate * maxmul) / 1;
-
-	/* Maximum divider = max_div */
-	/* Minimum multiplier = 2 */
-	maxdiv = PLL_DIV_MAX;
-	minrate = (parent_rate * 2) / maxdiv;
-
+	/* Check if parent_rate is a valid input rate */
 	if (parent_rate < characteristics->input.min ||
-	    parent_rate < characteristics->input.max)
-		return -ERANGE;
-
-	if (parent_rate < minrate || parent_rate > maxrate)
+	    parent_rate > characteristics->input.max)
 		return -ERANGE;
 
-	for (i = 0; i < characteristics->num_output; i++) {
-		if (parent_rate >= characteristics->output[i].min &&
-		    parent_rate <= characteristics->output[i].max)
-			break;
-	}
-
-	if (i >= characteristics->num_output)
-		return -ERANGE;
-
-	bestmul = rate / parent_rate;
-	rounddown = parent_rate % rate;
-	roundup = rate - rounddown;
-	bestremainder = roundup < rounddown ? roundup : rounddown;
-
-	if (!bestremainder) {
-		if (div)
-			*div = bestdiv;
-		if (mul)
-			*mul = bestmul;
-		if (index)
-			*index = i;
-		return rate;
-	}
-
-	maxdiv = 255 / (bestmul + 1);
-	if (parent_rate / maxdiv < characteristics->input.min)
-		maxdiv = parent_rate / characteristics->input.min;
-	mindiv = parent_rate / characteristics->input.max;
-	if (parent_rate % characteristics->input.max)
-		mindiv++;
-
-	for (tmpdiv = mindiv; tmpdiv < maxdiv; tmpdiv++) {
-		divrate = parent_rate / tmpdiv;
-
-		rounddown = rate % divrate;
-		roundup = divrate - rounddown;
-		remainder = roundup < rounddown ? roundup : rounddown;
-
+	/*
+	 * Calculate minimum divider based on the minimum multiplier, the
+	 * parent_rate and the requested rate.
+	 * Should always be 2 according to the input and output characteristics
+	 * of the PLL blocks.
+	 */
+	mindiv = (parent_rate * PLL_MUL_MIN) / rate;
+	if (!mindiv)
+		mindiv = 1;
+
+	/*
+	 * Calculate the maximum divider which is limited by PLL register
+	 * layout (limited by the MUL or DIV field size).
+	 */
+	maxdiv = DIV_ROUND_UP(parent_rate * PLL_MUL_MAX(layout), rate);
+	if (maxdiv > PLL_DIV_MAX)
+		maxdiv = PLL_DIV_MAX;
+
+	/*
+	 * Iterate over the acceptable divider values to find the best
+	 * divider/multiplier pair (the one that generates the closest
+	 * rate to the requested one).
+	 */
+	for (tmpdiv = mindiv; tmpdiv <= maxdiv; tmpdiv++) {
+		unsigned long remainder;
+		unsigned long tmprate;
+		unsigned long tmpmul;
+
+		/*
+		 * Calculate the multiplier associated with the current
+		 * divider that provide the closest rate to the requested one.
+		 */
+		tmpmul = DIV_ROUND_CLOSEST(rate, parent_rate / tmpdiv);
+		tmprate = (parent_rate / tmpdiv) * tmpmul;
+		if (tmprate > rate)
+			remainder = tmprate - rate;
+		else
+			remainder = rate - tmprate;
+
+		/*
+		 * Compare the remainder with the best remainder found until
+		 * now and elect a new best multiplier/divider pair if the
+		 * current remainder is smaller than the best one.
+		 */
 		if (remainder < bestremainder) {
 			bestremainder = remainder;
-			bestmul = rate / divrate;
 			bestdiv = tmpdiv;
+			bestmul = tmpmul;
+			bestrate = tmprate;
 		}
 
+		/*
+		 * We've found a perfect match!
+		 * Stop searching now and use this multiplier/divider pair.
+		 */
 		if (!remainder)
 			break;
 	}
 
-	rate = (parent_rate / bestdiv) * bestmul;
+	/* We haven't found any multiplier/divider pair => return -ERANGE */
+	if (bestrate < 0)
+		return bestrate;
+
+	/* Check if bestrate is a valid output rate  */
+	for (i = 0; i < characteristics->num_output; i++) {
+		if (bestrate >= characteristics->output[i].min &&
+		    bestrate <= characteristics->output[i].max)
+			break;
+	}
+
+	if (i >= characteristics->num_output)
+		return -ERANGE;
 
 	if (div)
 		*div = bestdiv;
 	if (mul)
-		*mul = bestmul;
+		*mul = bestmul - 1;
 	if (index)
 		*index = i;
 
-	return rate;
+	return bestrate;
 }
 
 static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
diff --git a/drivers/clk/at91/clk-slow.c b/drivers/clk/at91/clk-slow.c
index 0300c46ee247..32f7c1b36204 100644
--- a/drivers/clk/at91/clk-slow.c
+++ b/drivers/clk/at91/clk-slow.c
@@ -447,7 +447,7 @@ void __init of_at91sam9260_clk_slow_setup(struct device_node *np,
 	int i;
 
 	num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells");
-	if (num_parents <= 0 || num_parents > 1)
+	if (num_parents != 2)
 		return;
 
 	for (i = 0; i < num_parents; ++i) {
diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c
index 8c96307d7363..a76d03fd577b 100644
--- a/drivers/clk/at91/clk-system.c
+++ b/drivers/clk/at91/clk-system.c
@@ -119,13 +119,7 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name,
 	init.ops = &system_ops;
 	init.parent_names = &parent_name;
 	init.num_parents = 1;
-	/*
-	 * CLK_IGNORE_UNUSED is used to avoid ddrck switch off.
-	 * TODO : we should implement a driver supporting at91 ddr controller
-	 * (see drivers/memory) which would request and enable the ddrck clock.
-	 * When this is done we will be able to remove CLK_IGNORE_UNUSED flag.
-	 */
-	init.flags = CLK_SET_RATE_PARENT | CLK_IGNORE_UNUSED;
+	init.flags = CLK_SET_RATE_PARENT;
 
 	sys->id = id;
 	sys->hw.init = &init;
diff --git a/drivers/clk/at91/clk-usb.c b/drivers/clk/at91/clk-usb.c
index 7d1d26a4bd04..24b5b020753a 100644
--- a/drivers/clk/at91/clk-usb.c
+++ b/drivers/clk/at91/clk-usb.c
@@ -238,16 +238,22 @@ static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
 					  unsigned long *parent_rate)
 {
 	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
+	struct clk *parent = __clk_get_parent(hw->clk);
 	unsigned long bestrate = 0;
 	int bestdiff = -1;
 	unsigned long tmprate;
 	int tmpdiff;
 	int i = 0;
 
-	for (i = 0; i < 4; i++) {
+	for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
+		unsigned long tmp_parent_rate;
+
 		if (!usb->divisors[i])
 			continue;
-		tmprate = *parent_rate / usb->divisors[i];
+
+		tmp_parent_rate = rate * usb->divisors[i];
+		tmp_parent_rate = __clk_round_rate(parent, tmp_parent_rate);
+		tmprate = tmp_parent_rate / usb->divisors[i];
 		if (tmprate < rate)
 			tmpdiff = rate - tmprate;
 		else
@@ -256,6 +262,7 @@ static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
 		if (bestdiff < 0 || bestdiff > tmpdiff) {
 			bestrate = tmprate;
 			bestdiff = tmpdiff;
+			*parent_rate = tmp_parent_rate;
 		}
 
 		if (!bestdiff)
@@ -272,10 +279,13 @@ static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
 	int i;
 	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
 	struct at91_pmc *pmc = usb->pmc;
-	unsigned long div = parent_rate / rate;
+	unsigned long div;
 
-	if (parent_rate % rate)
+	if (!rate || parent_rate % rate)
 		return -EINVAL;
+
+	div = parent_rate / rate;
+
 	for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
 		if (usb->divisors[i] == div) {
 			tmp = pmc_read(pmc, AT91_CKGR_PLLBR) &
@@ -311,7 +321,7 @@ at91rm9200_clk_register_usb(struct at91_pmc *pmc, const char *name,
 	init.ops = &at91rm9200_usb_ops;
 	init.parent_names = &parent_name;
 	init.num_parents = 1;
-	init.flags = 0;
+	init.flags = CLK_SET_RATE_PARENT;
 
 	usb->hw.init = &init;
 	usb->pmc = pmc;
diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
index 524196bb35a5..386999b4f8eb 100644
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -337,6 +337,12 @@ static const struct of_device_id pmc_clk_ids[] __initconst = {
 		.data = of_at91sam9x5_clk_smd_setup,
 	},
 #endif
+#if defined(CONFIG_HAVE_AT91_H32MX)
+	{
+		.compatible = "atmel,sama5d4-clk-h32mx",
+		.data = of_sama5d4_clk_h32mx_setup,
+	},
+#endif
 	{ /*sentinel*/ }
 };
 
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 6c7625976113..52d2041fa3f6 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -120,4 +120,9 @@ extern void __init of_at91sam9x5_clk_smd_setup(struct device_node *np,
 					       struct at91_pmc *pmc);
 #endif
 
+#if defined(CONFIG_HAVE_AT91_SMD)
+extern void __init of_sama5d4_clk_h32mx_setup(struct device_node *np,
+					      struct at91_pmc *pmc);
+#endif
+
 #endif /* __PMC_H_ */