1 files changed, 305 insertions, 5 deletions

diff --git a/drivers/clk/at91/clk-master.c b/drivers/clk/at91/clk-master.c
index e7e0ba652de1..bd0d8a69a2cf 100644
--- a/drivers/clk/at91/clk-master.c
+++ b/drivers/clk/at91/clk-master.c
@@ -17,30 +17,49 @@
 #define MASTER_DIV_SHIFT	8
 #define MASTER_DIV_MASK		0x3
 
+#define PMC_MCR			0x30
+#define PMC_MCR_ID_MSK		GENMASK(3, 0)
+#define PMC_MCR_CMD		BIT(7)
+#define PMC_MCR_DIV		GENMASK(10, 8)
+#define PMC_MCR_CSS		GENMASK(20, 16)
+#define PMC_MCR_CSS_SHIFT	(16)
+#define PMC_MCR_EN		BIT(28)
+
+#define PMC_MCR_ID(x)		((x) & PMC_MCR_ID_MSK)
+
+#define MASTER_MAX_ID		4
+
 #define to_clk_master(hw) container_of(hw, struct clk_master, hw)
 
 struct clk_master {
 	struct clk_hw hw;
 	struct regmap *regmap;
+	spinlock_t *lock;
 	const struct clk_master_layout *layout;
 	const struct clk_master_characteristics *characteristics;
+	u32 *mux_table;
 	u32 mckr;
+	int chg_pid;
+	u8 id;
+	u8 parent;
+	u8 div;
 };
 
-static inline bool clk_master_ready(struct regmap *regmap)
+static inline bool clk_master_ready(struct clk_master *master)
 {
+	unsigned int bit = master->id ? AT91_PMC_MCKXRDY : AT91_PMC_MCKRDY;
 	unsigned int status;
 
-	regmap_read(regmap, AT91_PMC_SR, &status);
+	regmap_read(master->regmap, AT91_PMC_SR, &status);
 
-	return status & AT91_PMC_MCKRDY ? 1 : 0;
+	return !!(status & bit);
 }
 
 static int clk_master_prepare(struct clk_hw *hw)
 {
 	struct clk_master *master = to_clk_master(hw);
 
-	while (!clk_master_ready(master->regmap))
+	while (!clk_master_ready(master))
 		cpu_relax();
 
 	return 0;
@@ -50,7 +69,7 @@ static int clk_master_is_prepared(struct clk_hw *hw)
 {
 	struct clk_master *master = to_clk_master(hw);
 
-	return clk_master_ready(master->regmap);
+	return clk_master_ready(master);
 }
 
 static unsigned long clk_master_recalc_rate(struct clk_hw *hw,
@@ -143,6 +162,287 @@ at91_clk_register_master(struct regmap *regmap,
 	return hw;
 }
 
+static unsigned long
+clk_sama7g5_master_recalc_rate(struct clk_hw *hw,
+			       unsigned long parent_rate)
+{
+	struct clk_master *master = to_clk_master(hw);
+
+	return DIV_ROUND_CLOSEST_ULL(parent_rate, (1 << master->div));
+}
+
+static void clk_sama7g5_master_best_diff(struct clk_rate_request *req,
+					 struct clk_hw *parent,
+					 unsigned long parent_rate,
+					 long *best_rate,
+					 long *best_diff,
+					 u32 div)
+{
+	unsigned long tmp_rate, tmp_diff;
+
+	if (div == MASTER_PRES_MAX)
+		tmp_rate = parent_rate / 3;
+	else
+		tmp_rate = parent_rate >> div;
+
+	tmp_diff = abs(req->rate - tmp_rate);
+
+	if (*best_diff < 0 || *best_diff >= tmp_diff) {
+		*best_rate = tmp_rate;
+		*best_diff = tmp_diff;
+		req->best_parent_rate = parent_rate;
+		req->best_parent_hw = parent;
+	}
+}
+
+static int clk_sama7g5_master_determine_rate(struct clk_hw *hw,
+					     struct clk_rate_request *req)
+{
+	struct clk_master *master = to_clk_master(hw);
+	struct clk_rate_request req_parent = *req;
+	struct clk_hw *parent;
+	long best_rate = LONG_MIN, best_diff = LONG_MIN;
+	unsigned long parent_rate;
+	unsigned int div, i;
+
+	/* First: check the dividers of MCR. */
+	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
+		parent = clk_hw_get_parent_by_index(hw, i);
+		if (!parent)
+			continue;
+
+		parent_rate = clk_hw_get_rate(parent);
+		if (!parent_rate)
+			continue;
+
+		for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
+			clk_sama7g5_master_best_diff(req, parent, parent_rate,
+						     &best_rate, &best_diff,
+						     div);
+			if (!best_diff)
+				break;
+		}
+
+		if (!best_diff)
+			break;
+	}
+
+	/* Second: try to request rate form changeable parent. */
+	if (master->chg_pid < 0)
+		goto end;
+
+	parent = clk_hw_get_parent_by_index(hw, master->chg_pid);
+	if (!parent)
+		goto end;
+
+	for (div = 0; div < MASTER_PRES_MAX + 1; div++) {
+		if (div == MASTER_PRES_MAX)
+			req_parent.rate = req->rate * 3;
+		else
+			req_parent.rate = req->rate << div;
+
+		if (__clk_determine_rate(parent, &req_parent))
+			continue;
+
+		clk_sama7g5_master_best_diff(req, parent, req_parent.rate,
+					     &best_rate, &best_diff, div);
+
+		if (!best_diff)
+			break;
+	}
+
+end:
+	pr_debug("MCK: %s, best_rate = %ld, parent clk: %s @ %ld\n",
+		 __func__, best_rate,
+		 __clk_get_name((req->best_parent_hw)->clk),
+		req->best_parent_rate);
+
+	if (best_rate < 0)
+		return -EINVAL;
+
+	req->rate = best_rate;
+
+	return 0;
+}
+
+static u8 clk_sama7g5_master_get_parent(struct clk_hw *hw)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long flags;
+	u8 index;
+
+	spin_lock_irqsave(master->lock, flags);
+	index = clk_mux_val_to_index(&master->hw, master->mux_table, 0,
+				     master->parent);
+	spin_unlock_irqrestore(master->lock, flags);
+
+	return index;
+}
+
+static int clk_sama7g5_master_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long flags;
+
+	if (index >= clk_hw_get_num_parents(hw))
+		return -EINVAL;
+
+	spin_lock_irqsave(master->lock, flags);
+	master->parent = clk_mux_index_to_val(master->mux_table, 0, index);
+	spin_unlock_irqrestore(master->lock, flags);
+
+	return 0;
+}
+
+static int clk_sama7g5_master_enable(struct clk_hw *hw)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long flags;
+	unsigned int val, cparent;
+
+	spin_lock_irqsave(master->lock, flags);
+
+	regmap_write(master->regmap, PMC_MCR, PMC_MCR_ID(master->id));
+	regmap_read(master->regmap, PMC_MCR, &val);
+	regmap_update_bits(master->regmap, PMC_MCR,
+			   PMC_MCR_EN | PMC_MCR_CSS | PMC_MCR_DIV |
+			   PMC_MCR_CMD | PMC_MCR_ID_MSK,
+			   PMC_MCR_EN | (master->parent << PMC_MCR_CSS_SHIFT) |
+			   (master->div << MASTER_DIV_SHIFT) |
+			   PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+	cparent = (val & PMC_MCR_CSS) >> PMC_MCR_CSS_SHIFT;
+
+	/* Wait here only if parent is being changed. */
+	while ((cparent != master->parent) && !clk_master_ready(master))
+		cpu_relax();
+
+	spin_unlock_irqrestore(master->lock, flags);
+
+	return 0;
+}
+
+static void clk_sama7g5_master_disable(struct clk_hw *hw)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long flags;
+
+	spin_lock_irqsave(master->lock, flags);
+
+	regmap_write(master->regmap, PMC_MCR, master->id);
+	regmap_update_bits(master->regmap, PMC_MCR,
+			   PMC_MCR_EN | PMC_MCR_CMD | PMC_MCR_ID_MSK,
+			   PMC_MCR_CMD | PMC_MCR_ID(master->id));
+
+	spin_unlock_irqrestore(master->lock, flags);
+}
+
+static int clk_sama7g5_master_is_enabled(struct clk_hw *hw)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long flags;
+	unsigned int val;
+
+	spin_lock_irqsave(master->lock, flags);
+
+	regmap_write(master->regmap, PMC_MCR, master->id);
+	regmap_read(master->regmap, PMC_MCR, &val);
+
+	spin_unlock_irqrestore(master->lock, flags);
+
+	return !!(val & PMC_MCR_EN);
+}
+
+static int clk_sama7g5_master_set_rate(struct clk_hw *hw, unsigned long rate,
+				       unsigned long parent_rate)
+{
+	struct clk_master *master = to_clk_master(hw);
+	unsigned long div, flags;
+
+	div = DIV_ROUND_CLOSEST(parent_rate, rate);
+	if ((div > (1 << (MASTER_PRES_MAX - 1))) || (div & (div - 1)))
+		return -EINVAL;
+
+	if (div == 3)
+		div = MASTER_PRES_MAX;
+	else
+		div = ffs(div) - 1;
+
+	spin_lock_irqsave(master->lock, flags);
+	master->div = div;
+	spin_unlock_irqrestore(master->lock, flags);
+
+	return 0;
+}
+
+static const struct clk_ops sama7g5_master_ops = {
+	.enable = clk_sama7g5_master_enable,
+	.disable = clk_sama7g5_master_disable,
+	.is_enabled = clk_sama7g5_master_is_enabled,
+	.recalc_rate = clk_sama7g5_master_recalc_rate,
+	.determine_rate = clk_sama7g5_master_determine_rate,
+	.set_rate = clk_sama7g5_master_set_rate,
+	.get_parent = clk_sama7g5_master_get_parent,
+	.set_parent = clk_sama7g5_master_set_parent,
+};
+
+struct clk_hw * __init
+at91_clk_sama7g5_register_master(struct regmap *regmap,
+				 const char *name, int num_parents,
+				 const char **parent_names,
+				 u32 *mux_table,
+				 spinlock_t *lock, u8 id,
+				 bool critical, int chg_pid)
+{
+	struct clk_master *master;
+	struct clk_hw *hw;
+	struct clk_init_data init;
+	unsigned long flags;
+	unsigned int val;
+	int ret;
+
+	if (!name || !num_parents || !parent_names || !mux_table ||
+	    !lock || id > MASTER_MAX_ID)
+		return ERR_PTR(-EINVAL);
+
+	master = kzalloc(sizeof(*master), GFP_KERNEL);
+	if (!master)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &sama7g5_master_ops;
+	init.parent_names = parent_names;
+	init.num_parents = num_parents;
+	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+	if (chg_pid >= 0)
+		init.flags |= CLK_SET_RATE_PARENT;
+	if (critical)
+		init.flags |= CLK_IS_CRITICAL;
+
+	master->hw.init = &init;
+	master->regmap = regmap;
+	master->id = id;
+	master->chg_pid = chg_pid;
+	master->lock = lock;
+	master->mux_table = mux_table;
+
+	spin_lock_irqsave(master->lock, flags);
+	regmap_write(master->regmap, PMC_MCR, master->id);
+	regmap_read(master->regmap, PMC_MCR, &val);
+	master->parent = (val & PMC_MCR_CSS) >> PMC_MCR_CSS_SHIFT;
+	master->div = (val & PMC_MCR_DIV) >> MASTER_DIV_SHIFT;
+	spin_unlock_irqrestore(master->lock, flags);
+
+	hw = &master->hw;
+	ret = clk_hw_register(NULL, &master->hw);
+	if (ret) {
+		kfree(master);
+		hw = ERR_PTR(ret);
+	}
+
+	return hw;
+}
+
 const struct clk_master_layout at91rm9200_master_layout = {
 	.mask = 0x31F,
 	.pres_shift = 2,