2017-04-20 12:40:01

by Peter De Schrijver

Subject: [PATCH] clk: tegra: fix SS control on PLL enable/disable

PLL SS was only controlled when setting the PLL rate, not when the PLL
itself is enabled or disabled. This means that if the PLL rate was set
before the PLL is enabled, SS will not be enabled, even when configured.

Signed-off-by: Peter De Schrijver <[email protected]>
---
drivers/clk/tegra/clk-pll.c | 44 ++++++++++++++++++++++++--------------------
1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 159a854..e9bdb16 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -418,6 +418,26 @@ static void _clk_pll_disable(struct clk_hw *hw)
}
}

+static void pll_clk_start_ss(struct tegra_clk_pll *pll)
+{
+ if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
+ u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
+
+ val |= pll->params->ssc_ctrl_en_mask;
+ pll_writel(val, pll->params->ssc_ctrl_reg, pll);
+ }
+}
+
+static void pll_clk_stop_ss(struct tegra_clk_pll *pll)
+{
+ if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
+ u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
+
+ val &= ~pll->params->ssc_ctrl_en_mask;
+ pll_writel(val, pll->params->ssc_ctrl_reg, pll);
+ }
+}
+
static int clk_pll_enable(struct clk_hw *hw)
{
struct tegra_clk_pll *pll = to_clk_pll(hw);
@@ -431,6 +451,8 @@ static int clk_pll_enable(struct clk_hw *hw)

ret = clk_pll_wait_for_lock(pll);

+ pll_clk_start_ss(pll);
+
if (pll->lock)
spin_unlock_irqrestore(pll->lock, flags);

@@ -445,6 +467,8 @@ static void clk_pll_disable(struct clk_hw *hw)
if (pll->lock)
spin_lock_irqsave(pll->lock, flags);

+ pll_clk_stop_ss(pll);
+
_clk_pll_disable(hw);

if (pll->lock)
@@ -716,26 +740,6 @@ static void _update_pll_cpcon(struct tegra_clk_pll *pll,
pll_writel_misc(val, pll);
}

-static void pll_clk_start_ss(struct tegra_clk_pll *pll)
-{
- if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
- u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
-
- val |= pll->params->ssc_ctrl_en_mask;
- pll_writel(val, pll->params->ssc_ctrl_reg, pll);
- }
-}
-
-static void pll_clk_stop_ss(struct tegra_clk_pll *pll)
-{
- if (pll->params->defaults_set && pll->params->ssc_ctrl_reg) {
- u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
-
- val &= ~pll->params->ssc_ctrl_en_mask;
- pll_writel(val, pll->params->ssc_ctrl_reg, pll);
- }
-}
-
static int _program_pll(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
unsigned long rate)
{
--
1.9.1

2017-04-22 02:38:53

by Stephen Boyd

Subject: Re: [PATCH] clk: tegra: fix SS control on PLL enable/disable

On 04/20, Peter De Schrijver wrote:
> PLL SS was only controlled when setting the PLL rate, not when the PLL
> itself is enabled or disabled. This means that if the PLL rate was set
> before the PLL is enabled, SS will not be enabled, even when configured.
>
> Signed-off-by: Peter De Schrijver <[email protected]>

Fixes tag? Or this isn't a problem right now, just future fix?

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project