1 files changed, 283 insertions, 92 deletions

diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index afffc1547e20..1ea6579a760f 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -32,11 +32,9 @@
 #include <linux/io.h>
 #include <linux/math64.h>
 #include <linux/module.h>
-#include <linux/of_address.h>
-#include <linux/slab.h>
-#include <linux/string.h>
 
-#include "clkc.h"
+#include "clk-regmap.h"
+#include "clk-pll.h"
 
 static inline struct meson_clk_pll_data *
 meson_clk_pll_data(struct clk_regmap *clk)
@@ -44,21 +42,31 @@ meson_clk_pll_data(struct clk_regmap *clk)
 	return (struct meson_clk_pll_data *)clk->data;
 }
 
+static int __pll_round_closest_mult(struct meson_clk_pll_data *pll)
+{
+	if ((pll->flags & CLK_MESON_PLL_ROUND_CLOSEST) &&
+	    !MESON_PARM_APPLICABLE(&pll->frac))
+		return 1;
+
+	return 0;
+}
+
 static unsigned long __pll_params_to_rate(unsigned long parent_rate,
-					  const struct pll_params_table *pllt,
-					  u16 frac,
+					  unsigned int m, unsigned int n,
+					  unsigned int frac,
 					  struct meson_clk_pll_data *pll)
 {
-	u64 rate = (u64)parent_rate * pllt->m;
+	u64 rate = (u64)parent_rate * m;
+	unsigned int frac_max = pll->frac_max ? pll->frac_max :
+						(1 << pll->frac.width);
 
 	if (frac && MESON_PARM_APPLICABLE(&pll->frac)) {
 		u64 frac_rate = (u64)parent_rate * frac;
 
-		rate += DIV_ROUND_UP_ULL(frac_rate,
-					 (1 << pll->frac.width));
+		rate += DIV_ROUND_UP_ULL(frac_rate, frac_max);
 	}
 
-	return DIV_ROUND_UP_ULL(rate, pllt->n);
+	return DIV_ROUND_UP_ULL(rate, n);
 }
 
 static unsigned long meson_clk_pll_recalc_rate(struct clk_hw *hw,
@@ -66,35 +74,49 @@ static unsigned long meson_clk_pll_recalc_rate(struct clk_hw *hw,
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
-	struct pll_params_table pllt;
-	u16 frac;
+	unsigned int m, n, frac;
+
+	n = meson_parm_read(clk->map, &pll->n);
+
+	/*
+	 * On some HW, N is set to zero on init. This value is invalid as
+	 * it would result in a division by zero. The rate can't be
+	 * calculated in this case
+	 */
+	if (n == 0)
+		return 0;
 
-	pllt.n = meson_parm_read(clk->map, &pll->n);
-	pllt.m = meson_parm_read(clk->map, &pll->m);
+	m = meson_parm_read(clk->map, &pll->m);
 
 	frac = MESON_PARM_APPLICABLE(&pll->frac) ?
 		meson_parm_read(clk->map, &pll->frac) :
 		0;
 
-	return __pll_params_to_rate(parent_rate, &pllt, frac, pll);
+	return __pll_params_to_rate(parent_rate, m, n, frac, pll);
 }
 
-static u16 __pll_params_with_frac(unsigned long rate,
-				  unsigned long parent_rate,
-				  const struct pll_params_table *pllt,
-				  struct meson_clk_pll_data *pll)
+static unsigned int __pll_params_with_frac(unsigned long rate,
+					   unsigned long parent_rate,
+					   unsigned int m,
+					   unsigned int n,
+					   struct meson_clk_pll_data *pll)
 {
-	u16 frac_max = (1 << pll->frac.width);
-	u64 val = (u64)rate * pllt->n;
+	unsigned int frac_max = pll->frac_max ? pll->frac_max :
+						(1 << pll->frac.width);
+	u64 val = (u64)rate * n;
+
+	/* Bail out if we are already over the requested rate */
+	if (rate < parent_rate * m / n)
+		return 0;
 
 	if (pll->flags & CLK_MESON_PLL_ROUND_CLOSEST)
 		val = DIV_ROUND_CLOSEST_ULL(val * frac_max, parent_rate);
 	else
 		val = div_u64(val * frac_max, parent_rate);
 
-	val -= pllt->m * frac_max;
+	val -= m * frac_max;
 
-	return min((u16)val, (u16)(frac_max - 1));
+	return min((unsigned int)val, (frac_max - 1));
 }
 
 static bool meson_clk_pll_is_better(unsigned long rate,
@@ -102,115 +124,233 @@ static bool meson_clk_pll_is_better(unsigned long rate,
 				    unsigned long now,
 				    struct meson_clk_pll_data *pll)
 {
-	if (!(pll->flags & CLK_MESON_PLL_ROUND_CLOSEST) ||
-	    MESON_PARM_APPLICABLE(&pll->frac)) {
-		/* Round down */
-		if (now < rate && best < now)
-			return true;
-	} else {
+	if (__pll_round_closest_mult(pll)) {
 		/* Round Closest */
 		if (abs(now - rate) < abs(best - rate))
 			return true;
+	} else {
+		/* Round down */
+		if (now <= rate && best < now)
+			return true;
 	}
 
 	return false;
 }
 
-static const struct pll_params_table *
-meson_clk_get_pll_settings(unsigned long rate,
-			   unsigned long parent_rate,
-			   struct meson_clk_pll_data *pll)
+static int meson_clk_get_pll_table_index(unsigned int index,
+					 unsigned int *m,
+					 unsigned int *n,
+					 struct meson_clk_pll_data *pll)
 {
-	const struct pll_params_table *table = pll->table;
-	unsigned long best = 0, now = 0;
-	unsigned int i, best_i = 0;
+	if (!pll->table[index].n)
+		return -EINVAL;
 
-	if (!table)
-		return NULL;
+	*m = pll->table[index].m;
+	*n = pll->table[index].n;
 
-	for (i = 0; table[i].n; i++) {
-		now = __pll_params_to_rate(parent_rate, &table[i], 0, pll);
+	return 0;
+}
+
+static unsigned int meson_clk_get_pll_range_m(unsigned long rate,
+					      unsigned long parent_rate,
+					      unsigned int n,
+					      struct meson_clk_pll_data *pll)
+{
+	u64 val = (u64)rate * n;
+
+	if (__pll_round_closest_mult(pll))
+		return DIV_ROUND_CLOSEST_ULL(val, parent_rate);
+
+	return div_u64(val,  parent_rate);
+}
 
-		/* If we get an exact match, don't bother any further */
-		if (now == rate) {
-			return &table[i];
-		} else if (meson_clk_pll_is_better(rate, best, now, pll)) {
+static int meson_clk_get_pll_range_index(unsigned long rate,
+					 unsigned long parent_rate,
+					 unsigned int index,
+					 unsigned int *m,
+					 unsigned int *n,
+					 struct meson_clk_pll_data *pll)
+{
+	*n = index + 1;
+
+	/* Check the predivider range */
+	if (*n >= (1 << pll->n.width))
+		return -EINVAL;
+
+	if (*n == 1) {
+		/* Get the boundaries out the way */
+		if (rate <= pll->range->min * parent_rate) {
+			*m = pll->range->min;
+			return -ENODATA;
+		} else if (rate >= pll->range->max * parent_rate) {
+			*m = pll->range->max;
+			return -ENODATA;
+		}
+	}
+
+	*m = meson_clk_get_pll_range_m(rate, parent_rate, *n, pll);
+
+	/* the pre-divider gives a multiplier too big - stop */
+	if (*m >= (1 << pll->m.width))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int meson_clk_get_pll_get_index(unsigned long rate,
+				       unsigned long parent_rate,
+				       unsigned int index,
+				       unsigned int *m,
+				       unsigned int *n,
+				       struct meson_clk_pll_data *pll)
+{
+	if (pll->range)
+		return meson_clk_get_pll_range_index(rate, parent_rate,
+						     index, m, n, pll);
+	else if (pll->table)
+		return meson_clk_get_pll_table_index(index, m, n, pll);
+
+	return -EINVAL;
+}
+
+static int meson_clk_get_pll_settings(unsigned long rate,
+				      unsigned long parent_rate,
+				      unsigned int *best_m,
+				      unsigned int *best_n,
+				      struct meson_clk_pll_data *pll)
+{
+	unsigned long best = 0, now = 0;
+	unsigned int i, m, n;
+	int ret;
+
+	for (i = 0, ret = 0; !ret; i++) {
+		ret = meson_clk_get_pll_get_index(rate, parent_rate,
+						  i, &m, &n, pll);
+		if (ret == -EINVAL)
+			break;
+
+		now = __pll_params_to_rate(parent_rate, m, n, 0, pll);
+		if (meson_clk_pll_is_better(rate, best, now, pll)) {
 			best = now;
-			best_i = i;
+			*best_m = m;
+			*best_n = n;
+
+			if (now == rate)
+				break;
 		}
 	}
 
-	return (struct pll_params_table *)&table[best_i];
+	return best ? 0 : -EINVAL;
 }
 
-static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
-				     unsigned long *parent_rate)
+static int meson_clk_pll_determine_rate(struct clk_hw *hw,
+					struct clk_rate_request *req)
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
-	const struct pll_params_table *pllt =
-		meson_clk_get_pll_settings(rate, *parent_rate, pll);
+	unsigned int m, n, frac;
 	unsigned long round;
-	u16 frac;
+	int ret;
 
-	if (!pllt)
-		return meson_clk_pll_recalc_rate(hw, *parent_rate);
+	ret = meson_clk_get_pll_settings(req->rate, req->best_parent_rate,
+					 &m, &n, pll);
+	if (ret)
+		return ret;
 
-	round = __pll_params_to_rate(*parent_rate, pllt, 0, pll);
+	round = __pll_params_to_rate(req->best_parent_rate, m, n, 0, pll);
 
-	if (!MESON_PARM_APPLICABLE(&pll->frac) || rate == round)
-		return round;
+	if (!MESON_PARM_APPLICABLE(&pll->frac) || req->rate == round) {
+		req->rate = round;
+		return 0;
+	}
 
 	/*
 	 * The rate provided by the setting is not an exact match, let's
 	 * try to improve the result using the fractional parameter
 	 */
-	frac = __pll_params_with_frac(rate, *parent_rate, pllt, pll);
+	frac = __pll_params_with_frac(req->rate, req->best_parent_rate, m, n, pll);
+	req->rate = __pll_params_to_rate(req->best_parent_rate, m, n, frac, pll);
 
-	return __pll_params_to_rate(*parent_rate, pllt, frac, pll);
+	return 0;
 }
 
 static int meson_clk_pll_wait_lock(struct clk_hw *hw)
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
-	int delay = 24000000;
+	int delay = 5000;
 
 	do {
-		/* Is the clock locked now ? */
+		/* Is the clock locked now ? Time out after 100ms. */
 		if (meson_parm_read(clk->map, &pll->l))
 			return 0;
 
-		delay--;
-	} while (delay > 0);
+		udelay(20);
+	} while (--delay);
 
 	return -ETIMEDOUT;
 }
 
-static void meson_clk_pll_init(struct clk_hw *hw)
+static int meson_clk_pll_is_enabled(struct clk_hw *hw)
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
+	if (MESON_PARM_APPLICABLE(&pll->rst) &&
+	    meson_parm_read(clk->map, &pll->rst))
+		return 0;
+
+	if (!meson_parm_read(clk->map, &pll->en) ||
+	    !meson_parm_read(clk->map, &pll->l))
+		return 0;
+
+	return 1;
+}
+
+static int meson_clk_pll_init(struct clk_hw *hw)
+{
+	struct clk_regmap *clk = to_clk_regmap(hw);
+	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
+	int ret;
+
+	ret = clk_regmap_init(hw);
+	if (ret)
+		return ret;
+
+	/*
+	 * Keep the clock running, which was already initialized and enabled
+	 * from the bootloader stage, to avoid any glitches.
+	 */
+	if ((pll->flags & CLK_MESON_PLL_NOINIT_ENABLED) &&
+	    meson_clk_pll_is_enabled(hw))
+		return 0;
+
 	if (pll->init_count) {
-		meson_parm_write(clk->map, &pll->rst, 1);
+		if (MESON_PARM_APPLICABLE(&pll->rst))
+			meson_parm_write(clk->map, &pll->rst, 1);
+
 		regmap_multi_reg_write(clk->map, pll->init_regs,
 				       pll->init_count);
-		meson_parm_write(clk->map, &pll->rst, 0);
+
+		if (MESON_PARM_APPLICABLE(&pll->rst))
+			meson_parm_write(clk->map, &pll->rst, 0);
 	}
+
+	return 0;
 }
 
-static int meson_clk_pll_is_enabled(struct clk_hw *hw)
+static int meson_clk_pcie_pll_enable(struct clk_hw *hw)
 {
-	struct clk_regmap *clk = to_clk_regmap(hw);
-	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
+	int retries = 10;
 
-	if (meson_parm_read(clk->map, &pll->rst) ||
-	    !meson_parm_read(clk->map, &pll->en) ||
-	    !meson_parm_read(clk->map, &pll->l))
-		return 0;
+	do {
+		meson_clk_pll_init(hw);
+		if (!meson_clk_pll_wait_lock(hw))
+			return 0;
+		pr_info("Retry enabling PCIe PLL clock\n");
+	} while (--retries);
 
-	return 1;
+	return -EIO;
 }
 
 static int meson_clk_pll_enable(struct clk_hw *hw)
@@ -223,13 +363,34 @@ static int meson_clk_pll_enable(struct clk_hw *hw)
 		return 0;
 
 	/* Make sure the pll is in reset */
-	meson_parm_write(clk->map, &pll->rst, 1);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 1);
 
 	/* Enable the pll */
 	meson_parm_write(clk->map, &pll->en, 1);
 
 	/* Take the pll out reset */
-	meson_parm_write(clk->map, &pll->rst, 0);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 0);
+
+	/*
+	 * Compared with the previous SoCs, self-adaption current module
+	 * is newly added for A1, keep the new power-on sequence to enable the
+	 * PLL. The sequence is:
+	 * 1. enable the pll, delay for 10us
+	 * 2. enable the pll self-adaption current module, delay for 40us
+	 * 3. enable the lock detect module
+	 */
+	if (MESON_PARM_APPLICABLE(&pll->current_en)) {
+		udelay(10);
+		meson_parm_write(clk->map, &pll->current_en, 1);
+		udelay(40);
+	}
+
+	if (MESON_PARM_APPLICABLE(&pll->l_detect)) {
+		meson_parm_write(clk->map, &pll->l_detect, 1);
+		meson_parm_write(clk->map, &pll->l_detect, 0);
+	}
 
 	if (meson_clk_pll_wait_lock(hw))
 		return -EIO;
@@ -243,10 +404,15 @@ static void meson_clk_pll_disable(struct clk_hw *hw)
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
 
 	/* Put the pll is in reset */
-	meson_parm_write(clk->map, &pll->rst, 1);
+	if (MESON_PARM_APPLICABLE(&pll->rst))
+		meson_parm_write(clk->map, &pll->rst, 1);
 
 	/* Disable the pll */
 	meson_parm_write(clk->map, &pll->en, 0);
+
+	/* Disable PLL internal self-adaption current module */
+	if (MESON_PARM_APPLICABLE(&pll->current_en))
+		meson_parm_write(clk->map, &pll->current_en, 0);
 }
 
 static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
@@ -254,30 +420,28 @@ static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
-	const struct pll_params_table *pllt;
-	unsigned int enabled;
+	unsigned int enabled, m, n, frac = 0;
 	unsigned long old_rate;
-	u16 frac = 0;
+	int ret;
 
 	if (parent_rate == 0 || rate == 0)
 		return -EINVAL;
 
-	old_rate = rate;
+	old_rate = clk_hw_get_rate(hw);
 
-	pllt = meson_clk_get_pll_settings(rate, parent_rate, pll);
-	if (!pllt)
-		return -EINVAL;
+	ret = meson_clk_get_pll_settings(rate, parent_rate, &m, &n, pll);
+	if (ret)
+		return ret;
 
 	enabled = meson_parm_read(clk->map, &pll->en);
 	if (enabled)
 		meson_clk_pll_disable(hw);
 
-	meson_parm_write(clk->map, &pll->n, pllt->n);
-	meson_parm_write(clk->map, &pll->m, pllt->m);
-
+	meson_parm_write(clk->map, &pll->n, n);
+	meson_parm_write(clk->map, &pll->m, m);
 
 	if (MESON_PARM_APPLICABLE(&pll->frac)) {
-		frac = __pll_params_with_frac(rate, parent_rate, pllt, pll);
+		frac = __pll_params_with_frac(rate, parent_rate, m, n, pll);
 		meson_parm_write(clk->map, &pll->frac, frac);
 	}
 
@@ -285,9 +449,10 @@ static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (!enabled)
 		return 0;
 
-	if (meson_clk_pll_enable(hw)) {
-		pr_warn("%s: pll did not lock, trying to restore old rate %lu\n",
-			__func__, old_rate);
+	ret = meson_clk_pll_enable(hw);
+	if (ret) {
+		pr_warn("%s: pll %s didn't lock, trying to set old rate %lu\n",
+			__func__, clk_hw_get_name(hw), old_rate);
 		/*
 		 * FIXME: Do we really need/want this HACK ?
 		 * It looks unsafe. what happens if the clock gets into a
@@ -297,20 +462,46 @@ static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 		meson_clk_pll_set_rate(hw, old_rate, parent_rate);
 	}
 
-	return 0;
+	return ret;
 }
 
+/*
+ * The Meson G12A PCIE PLL is fined tuned to deliver a very precise
+ * 100MHz reference clock for the PCIe Analog PHY, and thus requires
+ * a strict register sequence to enable the PLL.
+ * To simplify, re-use the _init() op to enable the PLL and keep
+ * the other ops except set_rate since the rate is fixed.
+ */
+const struct clk_ops meson_clk_pcie_pll_ops = {
+	.init		= clk_regmap_init,
+	.recalc_rate	= meson_clk_pll_recalc_rate,
+	.determine_rate	= meson_clk_pll_determine_rate,
+	.is_enabled	= meson_clk_pll_is_enabled,
+	.enable		= meson_clk_pcie_pll_enable,
+	.disable	= meson_clk_pll_disable
+};
+EXPORT_SYMBOL_NS_GPL(meson_clk_pcie_pll_ops, "CLK_MESON");
+
 const struct clk_ops meson_clk_pll_ops = {
 	.init		= meson_clk_pll_init,
 	.recalc_rate	= meson_clk_pll_recalc_rate,
-	.round_rate	= meson_clk_pll_round_rate,
+	.determine_rate	= meson_clk_pll_determine_rate,
 	.set_rate	= meson_clk_pll_set_rate,
 	.is_enabled	= meson_clk_pll_is_enabled,
 	.enable		= meson_clk_pll_enable,
 	.disable	= meson_clk_pll_disable
 };
+EXPORT_SYMBOL_NS_GPL(meson_clk_pll_ops, "CLK_MESON");
 
 const struct clk_ops meson_clk_pll_ro_ops = {
+	.init		= clk_regmap_init,
 	.recalc_rate	= meson_clk_pll_recalc_rate,
 	.is_enabled	= meson_clk_pll_is_enabled,
 };
+EXPORT_SYMBOL_NS_GPL(meson_clk_pll_ro_ops, "CLK_MESON");
+
+MODULE_DESCRIPTION("Amlogic PLL driver");
+MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("CLK_MESON");