clk: samsung: Add enable/disable support for PLL35XX clocks

Some PLLs might be disabled by default after turning off and then on
a power domain which they belongs to.  To avoid configuring a disabled
PLL, add proper code for handling PLL enable/disable.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c
index 9617825..5229089 100644 (file)
--- a/drivers/clk/samsung/clk-pll.c
+++ b/drivers/clk/samsung/clk-pll.c
@@ -136,11 +136,39 @@ static const struct clk_ops samsung_pll3000_clk_ops = {
 #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_ENABLE_SHIFT   (31)
+
+static int samsung_pll35xx_enable(struct clk_hw *hw)
+{
+       struct samsung_clk_pll *pll = to_clk_pll(hw);
+       u32 tmp;
+
+       tmp = readl_relaxed(pll->con_reg);
+       tmp |= BIT(PLL35XX_ENABLE_SHIFT);
+       writel_relaxed(tmp, pll->con_reg);
+
+       /* wait_lock_time */
+       do {
+               cpu_relax();
+               tmp = readl_relaxed(pll->con_reg);
+       } while (!(tmp & BIT(PLL35XX_LOCK_STAT_SHIFT)));
+
+       return 0;
+}
+
+static void samsung_pll35xx_disable(struct clk_hw *hw)
+{
+       struct samsung_clk_pll *pll = to_clk_pll(hw);
+       u32 tmp;
+
+       tmp = readl_relaxed(pll->con_reg);
+       tmp &= ~BIT(PLL35XX_ENABLE_SHIFT);
+       writel_relaxed(tmp, pll->con_reg);
+}
 
 static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw,
                                unsigned long parent_rate)
@@ -210,12 +238,13 @@ static int samsung_pll35xx_set_rate(struct clk_hw *hw, unsigned long drate,
                        (rate->sdiv << PLL35XX_SDIV_SHIFT);
        writel_relaxed(tmp, pll->con_reg);
 
-       /* wait_lock_time */
-       do {
-               cpu_relax();
-               tmp = readl_relaxed(pll->con_reg);
-       } while (!(tmp & (PLL35XX_LOCK_STAT_MASK
-                               << PLL35XX_LOCK_STAT_SHIFT)));
+       /* wait_lock_time if enabled */
+       if (tmp & BIT(PLL35XX_ENABLE_SHIFT)) {
+               do {
+                       cpu_relax();
+                       tmp = readl_relaxed(pll->con_reg);
+               } while (!(tmp & BIT(PLL35XX_LOCK_STAT_SHIFT)));
+       }
        return 0;
 }
 
@@ -223,6 +252,8 @@ static const struct clk_ops samsung_pll35xx_clk_ops = {
        .recalc_rate = samsung_pll35xx_recalc_rate,
        .round_rate = samsung_pll_round_rate,
        .set_rate = samsung_pll35xx_set_rate,
+       .enable = samsung_pll35xx_enable,
+       .disable = samsung_pll35xx_disable,
 };
 
 static const struct clk_ops samsung_pll35xx_clk_min_ops = {