diff mbox series

[v2,2/6] clk: qcom: clk-alpha-pll: Update set_rate for Zonda PLL

Message ID 20240702-camcc-support-sm8150-v2-2-4baf54ec7333@quicinc.com (mailing list archive)
State Changes Requested, archived
Headers show
Series clk: qcom: sm8150: Add camera clock controller support for SM8150 | expand

Commit Message

Satya Priya Kakitapalli July 2, 2024, 3:50 p.m. UTC
The Zonda PLL has a 16 bit signed alpha and in the cases where the alpha
value is greater than 0.5, the L value needs to be adjusted accordingly.
Thus update the logic for the same.

Also, fix zonda set_rate failure when PLL is disabled. Currently,
clk_zonda_pll_set_rate polls for the PLL to lock even if the PLL is
disabled. However, if the PLL is disabled then LOCK_DET will never
assert and we'll return an error. There is no reason to poll LOCK_DET
if the PLL is already disabled, so skip polling in this case.

Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
---
 drivers/clk/qcom/clk-alpha-pll.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Comments

Dmitry Baryshkov July 3, 2024, 10:02 a.m. UTC | #1
On Tue, Jul 02, 2024 at 09:20:40PM GMT, Satya Priya Kakitapalli wrote:
> The Zonda PLL has a 16 bit signed alpha and in the cases where the alpha
> value is greater than 0.5, the L value needs to be adjusted accordingly.
> Thus update the logic for the same.
> 
> Also, fix zonda set_rate failure when PLL is disabled. Currently,
> clk_zonda_pll_set_rate polls for the PLL to lock even if the PLL is
> disabled. However, if the PLL is disabled then LOCK_DET will never
> assert and we'll return an error. There is no reason to poll LOCK_DET
> if the PLL is already disabled, so skip polling in this case.

Two separate commits, missing Fixes tags.

> 
> Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
> ---
>  drivers/clk/qcom/clk-alpha-pll.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
diff mbox series

Patch

diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
index 6107c144c0f5..d2bef078588f 100644
--- a/drivers/clk/qcom/clk-alpha-pll.c
+++ b/drivers/clk/qcom/clk-alpha-pll.c
@@ -2061,6 +2061,18 @@  static void clk_zonda_pll_disable(struct clk_hw *hw)
 	regmap_write(regmap, PLL_OPMODE(pll), 0x0);
 }
 
+static void zonda_pll_adjust_l_val(unsigned long rate, unsigned long prate, u32 *l)
+{
+	u64 remainder, quotient;
+
+	quotient = rate;
+	remainder = do_div(quotient, prate);
+	*l = quotient;
+
+	if ((remainder * 2) / prate)
+		*l = *l + 1;
+}
+
 static int clk_zonda_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long prate)
 {
@@ -2077,9 +2089,15 @@  static int clk_zonda_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (ret < 0)
 		return ret;
 
+	if (a & BIT(15))
+		zonda_pll_adjust_l_val(rate, prate, &l);
+
 	regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL(pll), a);
 	regmap_write(pll->clkr.regmap, PLL_L_VAL(pll), l);
 
+	if (!clk_hw_is_enabled(hw))
+		return 0;
+
 	/* Wait before polling for the frequency latch */
 	udelay(5);