[PATCH v2 4/5] clk: samsung: Add set_rate() clk_ops for PLL36xx

Vikas Sajjan vikas.sajjan at linaro.org
Wed May 29 09:37:56 EDT 2013


This patch adds set_rate and round_rate clk_ops for PLL36xx

Signed-off-by: Vikas Sajjan <vikas.sajjan at linaro.org>
---
 drivers/clk/samsung/clk-pll.c |   59 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index 1fba7ef..3872161 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -210,6 +210,9 @@ struct clk * __init samsung_clk_register_pll35xx(const char *name,
 #define PLL36XX_CON0_OFFSET             0x100
 #define PLL36XX_CON1_OFFSET             0x104
 
+/* Maximum lock time can be 3000 * PDIV cycles */
+#define PLL36XX_LOCK_FACTOR	3000
+
 #define PLL36XX_KDIV_MASK	(0xFFFF)
 #define PLL36XX_MDIV_MASK	(0x1FF)
 #define PLL36XX_PDIV_MASK	(0x3F)
@@ -217,6 +220,8 @@ struct clk * __init samsung_clk_register_pll35xx(const char *name,
 #define PLL36XX_MDIV_SHIFT	(16)
 #define PLL36XX_PDIV_SHIFT	(8)
 #define PLL36XX_SDIV_SHIFT	(0)
+#define PLL36XX_KDIV_SHIFT	(0)
+#define PLL36XX_LOCK_STAT_SHIFT (29)
 
 static unsigned long samsung_pll36xx_recalc_rate(struct clk_hw *hw,
 				unsigned long parent_rate)
@@ -239,8 +244,57 @@ static unsigned long samsung_pll36xx_recalc_rate(struct clk_hw *hw,
 	return (unsigned long)fvco;
 }
 
+static int samsung_pll36xx_set_rate(struct clk_hw *hw, unsigned long drate,
+					unsigned long parent_rate)
+{
+	struct samsung_clk_pll *pll = to_clk_pll(hw);
+	u32 tmp, pll_con0, pll_con1;
+	const struct samsung_pll_rate_table *rate;
+
+	rate = samsung_get_pll_settings(pll, drate);
+	if (!rate) {
+		pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
+			drate, __clk_get_name(hw->clk));
+		return -EINVAL;
+	}
+
+	pll_con0 = pll_readl(pll, PLL36XX_CON0_OFFSET);
+	pll_con1 = pll_readl(pll, PLL36XX_CON1_OFFSET);
+
+	/* Set PLL lock time. */
+	pll_writel(pll, (rate->pdiv * PLL36XX_LOCK_FACTOR),
+			PLL36XX_LOCK_OFFSET);
+
+	 /* Change PLL PMS values */
+	pll_con0 &= ~((PLL36XX_MDIV_MASK << PLL36XX_MDIV_SHIFT) |
+			(PLL36XX_PDIV_MASK << PLL36XX_PDIV_SHIFT) |
+			(PLL36XX_SDIV_MASK << PLL36XX_SDIV_SHIFT));
+	pll_con0 |= (rate->mdiv << PLL36XX_MDIV_SHIFT) |
+			(rate->pdiv << PLL36XX_PDIV_SHIFT) |
+			(rate->sdiv << PLL36XX_SDIV_SHIFT);
+	pll_writel(pll, pll_con0, PLL36XX_CON0_OFFSET);
+
+	pll_con1 &= ~(PLL36XX_KDIV_MASK << PLL36XX_KDIV_SHIFT);
+	pll_con1 |= rate->kdiv << PLL36XX_KDIV_SHIFT;
+	pll_writel(pll, pll_con1, PLL36XX_CON1_OFFSET);
+
+	/* wait_lock_time */
+	do {
+		cpu_relax();
+		tmp = pll_readl(pll, PLL36XX_CON0_OFFSET);
+	} while (!(tmp & (1 << PLL36XX_LOCK_STAT_SHIFT)));
+
+	return 0;
+}
+
 static const struct clk_ops samsung_pll36xx_clk_ops = {
 	.recalc_rate = samsung_pll36xx_recalc_rate,
+	.set_rate = samsung_pll36xx_set_rate,
+	.round_rate = samsung_pll_round_rate,
+};
+
+static const struct clk_ops samsung_pll36xx_clk_min_ops = {
+	.recalc_rate = samsung_pll36xx_recalc_rate,
 };
 
 struct clk * __init samsung_clk_register_pll36xx(const char *name,
@@ -264,6 +318,11 @@ struct clk * __init samsung_clk_register_pll36xx(const char *name,
 	init.parent_names = &pname;
 	init.num_parents = 1;
 
+	if (rate_table && rate_count)
+		init.ops = &samsung_pll36xx_clk_ops;
+	else
+		init.ops = &samsung_pll36xx_clk_min_ops;
+
 	pll->hw.init = &init;
 	pll->base = base;
 	pll->rate_table = rate_table;
-- 
1.7.9.5




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