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[3/5] clk: samsung: Add set_rate() clk_ops for PLL35XX

Message ID 1369371177-5413-4-git-send-email-vikas.sajjan@linaro.org
State New
Headers show

Commit Message

Vikas C Sajjan May 24, 2013, 4:52 a.m. UTC 
From: Yadwinder Singh Brar <yadi.brar@samsung.com>

Adds set_rate() and round_rate() clk_ops for PLL35XX

The round_rate() implemenation as of now is dummy, it returns the same rate
which is passed as input.

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
---
 drivers/clk/samsung/clk-pll.c |   95 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 94 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index b8c0260..291cc9e 100644
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -11,6 +11,7 @@ 
 
 #include <linux/errno.h>
 #include <linux/sort.h>
+#include <linux/bsearch.h>
 #include "clk.h"
 #include "clk-pll.h"
 
@@ -36,6 +37,21 @@  static int samsung_compare_rate(const void *_a, const void *_b)
 	return a->rate - b->rate;
 }
 
+static struct samsung_pll_rate_table *samsung_get_pll_settings(
+				struct samsung_clk_pll *pll, unsigned long rate)
+{
+	struct samsung_pll_rate_table req_rate, *tmp;
+
+	req_rate.rate = rate;
+	tmp = bsearch(&req_rate, pll->rate_table, pll->rate_count,
+			sizeof(struct samsung_pll_rate_table),
+			samsung_compare_rate);
+	if (tmp)
+		return tmp;
+
+	return NULL;
+}
+
 /*
  * PLL35xx Clock Type
  */
@@ -46,9 +62,15 @@  static int samsung_compare_rate(const void *_a, const void *_b)
 #define PLL35XX_MDIV_MASK       (0x3FF)
 #define PLL35XX_PDIV_MASK       (0x3F)
 #define PLL35XX_SDIV_MASK       (0x7)
+#define PLL35XX_LOCK_STAT_MASK  (0x1)
 #define PLL35XX_MDIV_SHIFT      (16)
 #define PLL35XX_PDIV_SHIFT      (8)
 #define PLL35XX_SDIV_SHIFT      (0)
+#define PLL35XX_LOCK_STAT_SHIFT (29)
+
+#define PLL35XX_MDIV(_tmp) ((_tmp) & (PLL35XX_MDIV_MASK << PLL35XX_MDIV_SHIFT))
+#define PLL35XX_PDIV(_tmp) ((_tmp) & (PLL35XX_PDIV_MASK << PLL35XX_PDIV_SHIFT))
+#define PLL35XX_SDIV(_tmp) ((_tmp) & (PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT))
 
 static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw,
 				unsigned long parent_rate)
@@ -68,8 +90,76 @@  static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw,
 	return (unsigned long)fvco;
 }
 
-static const struct clk_ops samsung_pll35xx_clk_ops = {
+static inline bool samsung_pll35xx_mp_change(u32 mdiv, u32 pdiv, u32 pll_con)
+{
+	if ((mdiv != PLL35XX_MDIV(pll_con)) || (pdiv != PLL35XX_PDIV(pll_con)))
+		return 1;
+	else
+		return 0;
+}
+
+static int samsung_pll35xx_set_rate(struct clk_hw *hw, unsigned long drate,
+					unsigned long prate)
+{
+	struct samsung_clk_pll *pll = to_clk_pll(hw);
+	struct samsung_pll_rate_table *rate;
+
+	u32 tmp, mdiv, pdiv, sdiv;
+
+	/* Get required rate settings from table */
+	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;
+	}
+
+	mdiv = PLL35XX_MDIV(rate->pll_con0);
+	pdiv = PLL35XX_PDIV(rate->pll_con0);
+	sdiv = PLL35XX_SDIV(rate->pll_con0);
+
+	tmp = pll_readl(pll, PLL35XX_CON0_OFFSET);
+
+	if (!(samsung_pll35xx_mp_change(mdiv, pdiv, tmp))) {
+		/* If only s change, change just s value only*/
+		tmp &= ~(PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT);
+		tmp |= sdiv;
+		pll_writel(pll, tmp, PLL35XX_CON0_OFFSET);
+	} else {
+		/* Set PLL lock time.
+		   Maximum lock time can be 270 * PDIV cycles */
+		pll_writel(pll, (pdiv >> PLL35XX_PDIV_SHIFT) * 270,
+				PLL35XX_LOCK_OFFSET);
+
+		/* Change PLL PMS values */
+		tmp &= ~((PLL35XX_MDIV_MASK << PLL35XX_MDIV_SHIFT) |
+				(PLL35XX_PDIV_MASK << PLL35XX_PDIV_SHIFT) |
+				(PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT));
+		tmp |= mdiv | pdiv | sdiv;
+		pll_writel(pll, tmp, PLL35XX_CON0_OFFSET);
+
+		/* wait_lock_time */
+		do {
+			cpu_relax();
+			tmp = pll_readl(pll, PLL35XX_CON0_OFFSET);
+		} while (!(tmp & (PLL35XX_LOCK_STAT_MASK
+				<< PLL35XX_LOCK_STAT_SHIFT)));
+	}
+
+	return 0;
+}
+
+static long samsung_pll35xx_round_rate(struct clk_hw *hw,
+			unsigned long drate, unsigned long *prate)
+{
+	/* Clock framework cries without this, so implemented dummy */
+	return drate;
+}
+
+static struct clk_ops samsung_pll35xx_clk_ops = {
 	.recalc_rate = samsung_pll35xx_recalc_rate,
+	.round_rate = samsung_pll35xx_round_rate,
+	.set_rate = samsung_pll35xx_set_rate,
 };
 
 struct clk * __init samsung_clk_register_pll35xx(const char *name,
@@ -102,6 +192,9 @@  struct clk * __init samsung_clk_register_pll35xx(const char *name,
 		sort(pll->rate_table, pll->rate_count,
 			sizeof(struct samsung_pll_rate_table),
 			samsung_compare_rate, NULL);
+	} else {
+		samsung_pll35xx_clk_ops.round_rate = NULL;
+		samsung_pll35xx_clk_ops.set_rate = NULL;
 	}
 
 	clk = clk_register(NULL, &pll->hw);