[PATCH] clk: tegra: pllc and pllxc should use pdiv_map

[Peter De Schrijver]

The pllc and pllxc code weren't always using the correct pdiv_map to
map between the post divider value and the hw p field. This could result
in illegal values being programmed in the hw.

Signed-off-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
---
 drivers/clk/tegra/clk-pll.c |  162 ++++++++++++++++++++++---------------------
 1 files changed, 82 insertions(+), 80 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 17c2cc0..85bec1d 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -143,24 +143,6 @@
 #define divn_max(p) (divn_mask(p))
 #define divp_max(p) (1 << (divp_mask(p)))
 
-
-#ifdef CONFIG_ARCH_TEGRA_114_SOC
-/* PLLXC has 4-bit PDIV, but entry 15 is not allowed in h/w */
-#define PLLXC_PDIV_MAX			14
-
-/* non-monotonic mapping below is not a typo */
-static u8 pllxc_p[PLLXC_PDIV_MAX + 1] = {
-	/* PDIV: 0, 1, 2, 3, 4, 5, 6,  7,  8,  9, 10, 11, 12, 13, 14 */
-	/* p: */ 1, 2, 3, 4, 5, 6, 8, 10, 12, 16, 12, 16, 20, 24, 32
-};
-
-#define PLLCX_PDIV_MAX 7
-static u8 pllcx_p[PLLCX_PDIV_MAX + 1] = {
-	/* PDIV: 0, 1, 2, 3, 4, 5,  6,  7 */
-	/* p: */ 1, 2, 3, 4, 6, 8, 12, 16
-};
-#endif
-
 static void clk_pll_enable_lock(struct tegra_clk_pll *pll)
 {
 	u32 val;
@@ -297,6 +279,39 @@ static void clk_pll_disable(struct clk_hw *hw)
 		spin_unlock_irqrestore(pll->lock, flags);
 }
 
+static int _p_div_to_hw(struct clk_hw *hw, u8 p_div)
+{
+	struct tegra_clk_pll *pll = to_clk_pll(hw);
+	struct pdiv_map *p_tohw = pll->params->pdiv_tohw;
+
+	if (p_tohw) {
+		while (p_tohw->pdiv) {
+			if (p_div <= p_tohw->pdiv)
+				return p_tohw->hw_val;
+			p_tohw++;
+		}
+		return -EINVAL;
+	}
+	return -EINVAL;
+}
+
+static int _hw_to_p_div(struct clk_hw *hw, u8 p_div_hw)
+{
+	struct tegra_clk_pll *pll = to_clk_pll(hw);
+	struct pdiv_map *p_tohw = pll->params->pdiv_tohw;
+
+	if (p_tohw) {
+		while (p_tohw->pdiv) {
+			if (p_div_hw == p_tohw->hw_val)
+				return p_tohw->pdiv;
+			p_tohw++;
+		}
+		return -EINVAL;
+	}
+
+	return 1 << p_div_hw;
+}
+
 static int _get_table_rate(struct clk_hw *hw,
 			   struct tegra_clk_pll_freq_table *cfg,
 			   unsigned long rate, unsigned long parent_rate)
@@ -326,9 +341,9 @@ static int _calc_rate(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
 		      unsigned long rate, unsigned long parent_rate)
 {
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
-	struct pdiv_map *p_tohw = pll->params->pdiv_tohw;
 	unsigned long cfreq;
 	u32 p_div = 0;
+	int ret;
 
 	switch (parent_rate) {
 	case 12000000:
@@ -369,20 +384,16 @@ static int _calc_rate(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
 	    || cfg->output_rate > pll->params->vco_max) {
 		pr_err("%s: Failed to set %s rate %lu\n",
 		       __func__, __clk_get_name(hw->clk), rate);
+		WARN_ON(1);
 		return -EINVAL;
 	}
 
-	if (p_tohw) {
-		p_div = 1 << p_div;
-		while (p_tohw->pdiv) {
-			if (p_div <= p_tohw->pdiv) {
-				cfg->p = p_tohw->hw_val;
-				break;
-			}
-			p_tohw++;
-		}
-		if (!p_tohw->pdiv)
-			return -EINVAL;
+	if (pll->params->pdiv_tohw) {
+		ret = _p_div_to_hw(hw, 1 << p_div);
+		if (ret < 0)
+			return ret;
+		else
+			cfg->p = ret;
 	} else
 		cfg->p = p_div;
 
@@ -485,9 +496,10 @@ static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 	}
 
 	if (_get_table_rate(hw, &cfg, rate, parent_rate) &&
-	    _calc_rate(hw, &cfg, rate, parent_rate))
+	    _calc_rate(hw, &cfg, rate, parent_rate)) {
+		WARN_ON(1);
 		return -EINVAL;
-
+	}
 	if (pll->lock)
 		spin_lock_irqsave(pll->lock, flags);
 
@@ -507,7 +519,6 @@ static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 {
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
 	struct tegra_clk_pll_freq_table cfg;
-	u64 output_rate = *prate;
 
 	if (pll->flags & TEGRA_PLL_FIXED)
 		return pll->fixed_rate;
@@ -517,13 +528,12 @@ static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 		return __clk_get_rate(hw->clk);
 
 	if (_get_table_rate(hw, &cfg, rate, *prate) &&
-	    _calc_rate(hw, &cfg, rate, *prate))
+	    _calc_rate(hw, &cfg, rate, *prate)) {
+		WARN_ON(1);
 		return -EINVAL;
+	}
 
-	output_rate *= cfg.n;
-	do_div(output_rate, cfg.m * (1 << cfg.p));
-
-	return output_rate;
+	return cfg.output_rate;
 }
 
 static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
@@ -531,7 +541,6 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
 {
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
 	struct tegra_clk_pll_freq_table cfg;
-	struct pdiv_map *p_tohw = pll->params->pdiv_tohw;
 	u32 val;
 	u64 rate = parent_rate;
 	int pdiv;
@@ -553,21 +562,11 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
 
 	_get_pll_mnp(pll, &cfg);
 
-	if (p_tohw) {
-		while (p_tohw->pdiv) {
-			if (cfg.p == p_tohw->hw_val) {
-				pdiv = p_tohw->pdiv;
-				break;
-			}
-			p_tohw++;
-		}
-
-		if (!p_tohw->pdiv) {
-			WARN_ON(1);
-			pdiv = 1;
-		}
-	} else
-		pdiv = 1 << cfg.p;
+	pdiv = _hw_to_p_div(hw, cfg.p);
+	if (pdiv < 0) {
+		WARN_ON(1);
+		pdiv = 1;
+	}
 
 	cfg.m *= pdiv;
 
@@ -769,16 +768,22 @@ static int _calc_dynamic_ramp_rate(struct clk_hw *hw,
 {
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
 	unsigned int p;
+	int p_div;
 
 	if (!rate)
 		return -EINVAL;
 
 	p = DIV_ROUND_UP(pll->params->vco_min, rate);
 	cfg->m = _pll_fixed_mdiv(pll->params, parent_rate);
-	cfg->p = p;
-	cfg->output_rate = rate * cfg->p;
+	cfg->output_rate = rate * p;
 	cfg->n = cfg->output_rate * cfg->m / parent_rate;
 
+	p_div = _p_div_to_hw(hw, p);
+	if (p_div < 0)
+		return p_div;
+	else
+		cfg->p = p_div;
+
 	if (cfg->n > divn_max(pll) || cfg->output_rate > pll->params->vco_max)
 		return -EINVAL;
 
@@ -790,18 +795,25 @@ static int _pll_ramp_calc_pll(struct clk_hw *hw,
 			      unsigned long rate, unsigned long parent_rate)
 {
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
-	int err = 0;
+	int err = 0, p_div;
 
 	err = _get_table_rate(hw, cfg, rate, parent_rate);
 	if (err < 0)
 		err = _calc_dynamic_ramp_rate(hw, cfg, rate, parent_rate);
-	else if (cfg->m != _pll_fixed_mdiv(pll->params, parent_rate)) {
+	else {
+		if (cfg->m != _pll_fixed_mdiv(pll->params, parent_rate)) {
 			WARN_ON(1);
 			err = -EINVAL;
 			goto out;
+		}
+		p_div = _p_div_to_hw(hw, cfg->p);
+		if (p_div < 0)
+			return p_div;
+		else
+			cfg->p = p_div;
 	}
 
-	if (!cfg->p || (cfg->p >  pll->params->max_p))
+	if (cfg->p >  pll->params->max_p)
 		err = -EINVAL;
 
 out:
@@ -815,7 +827,6 @@ static int clk_pllxc_set_rate(struct clk_hw *hw, unsigned long rate,
 	struct tegra_clk_pll_freq_table cfg, old_cfg;
 	unsigned long flags = 0;
 	int ret = 0;
-	u8 old_p;
 
 	ret = _pll_ramp_calc_pll(hw, &cfg, rate, parent_rate);
 	if (ret < 0)
@@ -826,11 +837,8 @@ static int clk_pllxc_set_rate(struct clk_hw *hw, unsigned long rate,
 
 	_get_pll_mnp(pll, &old_cfg);
 
-	old_p = pllxc_p[old_cfg.p];
-	if (old_cfg.m != cfg.m || old_cfg.n != cfg.n || old_p != cfg.p) {
-		cfg.p -= 1;
+	if (old_cfg.m != cfg.m || old_cfg.n != cfg.n || old_cfg.p != cfg.p)
 		ret = _program_pll(hw, &cfg, rate);
-	}
 
 	if (pll->lock)
 		spin_unlock_irqrestore(pll->lock, flags);
@@ -842,15 +850,19 @@ static long clk_pll_ramp_round_rate(struct clk_hw *hw, unsigned long rate,
 				unsigned long *prate)
 {
 	struct tegra_clk_pll_freq_table cfg;
-	int ret = 0;
+	int ret = 0, p_div;
 	u64 output_rate = *prate;
 
 	ret = _pll_ramp_calc_pll(hw, &cfg, rate, *prate);
 	if (ret < 0)
 		return ret;
 
+	p_div = _hw_to_p_div(hw, cfg.p);
+	if (p_div < 0)
+		return p_div;
+
 	output_rate *= cfg.n;
-	do_div(output_rate, cfg.m * cfg.p);
+	do_div(output_rate, cfg.m * p_div);
 
 	return output_rate;
 }
@@ -881,8 +893,6 @@ static int clk_pllm_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (ret < 0)
 		goto out;
 
-	cfg.p -= 1;
-
 	val = readl_relaxed(pll->pmc + PMC_PLLM_WB0_OVERRIDE);
 	if (val & PMC_PLLP_WB0_OVERRIDE_PLLM_OVERRIDE) {
 		val = readl_relaxed(pll->pmc + PMC_PLLM_WB0_OVERRIDE_2);
@@ -1010,13 +1020,10 @@ static int _pllcx_update_dynamic_coef(struct tegra_clk_pll *pll,
 static int clk_pllc_set_rate(struct clk_hw *hw, unsigned long rate,
 				unsigned long parent_rate)
 {
-	struct tegra_clk_pll_freq_table cfg;
+	struct tegra_clk_pll_freq_table cfg, old_cfg;
 	struct tegra_clk_pll *pll = to_clk_pll(hw);
 	unsigned long flags = 0;
 	int state, ret = 0;
-	u32 val;
-	u16 old_m, old_n;
-	u8 old_p;
 
 	if (pll->lock)
 		spin_lock_irqsave(pll->lock, flags);
@@ -1025,21 +1032,16 @@ static int clk_pllc_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (ret < 0)
 		goto out;
 
-	val = pll_readl_base(pll);
-	old_m = (val >> pll->divm_shift) & (divm_mask(pll));
-	old_n = (val >> pll->divn_shift) & (divn_mask(pll));
-	old_p = pllcx_p[(val >> pll->divp_shift) & (divp_mask(pll))];
+	_get_pll_mnp(pll, &old_cfg);
 
-	if (cfg.m != old_m) {
+	if (cfg.m != old_cfg.m) {
 		WARN_ON(1);
 		goto out;
 	}
 
-	if (old_n == cfg.n && old_p == cfg.p)
+	if (old_cfg.n == cfg.n && old_cfg.p == cfg.p)
 		goto out;
 
-	cfg.p -= 1;
-
 	state = clk_pll_is_enabled(hw);
 	if (state)
 		_clk_pllc_disable(hw);
-- 
1.7.7.rc0.72.g4b5ea.dirty

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