[PATCH 12/13] clk: qcom: support for 2 bit PLL post divider

From: Abhishek Sahu
Date: Thu Sep 28 2017 - 13:52:07 EST


Current PLL driver only supports 4 bit PLL post divider so
modified the PLL divider operations to support 2 bit PLL
post divider.

Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
---
drivers/clk/qcom/clk-alpha-pll.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
index c682387..62b84fa 100644
--- a/drivers/clk/qcom/clk-alpha-pll.c
+++ b/drivers/clk/qcom/clk-alpha-pll.c
@@ -39,7 +39,6 @@
# define PLL_LOCK_DET BIT(31)

# define PLL_POST_DIV_SHIFT 8
-# define PLL_POST_DIV_MASK 0xf
# define PLL_ALPHA_EN BIT(24)
# define PLL_ALPHA_MODE BIT(25)
# define PLL_VCO_SHIFT 20
@@ -822,7 +821,7 @@ static int clk_alpha_pll_hwfsm_is_enabled(struct clk_hw *hw)
&ctl);

ctl >>= PLL_POST_DIV_SHIFT;
- ctl &= PLL_POST_DIV_MASK;
+ ctl &= BIT(pll->width) - 1;

return parent_rate >> fls(ctl);
}
@@ -836,13 +835,26 @@ static int clk_alpha_pll_hwfsm_is_enabled(struct clk_hw *hw)
{ }
};

+static const struct clk_div_table clk_alpha_2bit_div_table[] = {
+ { 0x0, 1 },
+ { 0x1, 2 },
+ { 0x3, 4 },
+ { }
+};
+
static long
clk_alpha_pll_postdiv_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);
+ const struct clk_div_table *table;

- return divider_round_rate(hw, rate, prate, clk_alpha_div_table,
+ if (pll->width == 2)
+ table = clk_alpha_2bit_div_table;
+ else
+ table = clk_alpha_div_table;
+
+ return divider_round_rate(hw, rate, prate, table,
pll->width, CLK_DIVIDER_POWER_OF_TWO);
}

@@ -857,7 +869,7 @@ static int clk_alpha_pll_postdiv_set_rate(struct clk_hw *hw, unsigned long rate,

return regmap_update_bits(pll->clkr.regmap, pll->offset +
pll_user_ctl(pll->pll_type),
- PLL_POST_DIV_MASK << PLL_POST_DIV_SHIFT,
+ (BIT(pll->width) - 1) << PLL_POST_DIV_SHIFT,
div << PLL_POST_DIV_SHIFT);
}

--
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