diff mbox series

[RFC,v1,3/3] clk: meson: pll: switch to determine_rate for the PLL ops

Message ID 20210517203724.1006254-4-martin.blumenstingl@googlemail.com (mailing list archive)
State Superseded
Delegated to: Neil Armstrong
Headers show
Series clk: meson: rounding for fast clocks on 32-bit SoCs | expand

Commit Message

Martin Blumenstingl May 17, 2021, 8:37 p.m. UTC
This increases the maxmium supported frequency on 32-bit systems from
2^31 (signed long as used by clk_ops.round_rate, maximum value:
approx. 2.14GHz) to 2^32 (unsigned long as used by
clk_ops.determine_rate, maximum value: approx. 4.29GHz).
On Meson8/8b/8m2 the HDMI PLL and it's OD (post-dividers) are
capable of running at up to 2.97GHz. So switch the divider
implementation in clk-regmap to clk_ops.determine_rate to support these
higher frequencies on 32-bit systems.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
 drivers/clk/meson/clk-pll.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

Comments

Jerome Brunet May 18, 2021, 7:50 a.m. UTC | #1
On Mon 17 May 2021 at 22:37, Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote:

> This increases the maxmium supported frequency on 32-bit systems from
> 2^31 (signed long as used by clk_ops.round_rate, maximum value:
> approx. 2.14GHz) to 2^32 (unsigned long as used by
> clk_ops.determine_rate, maximum value: approx. 4.29GHz).
> On Meson8/8b/8m2 the HDMI PLL and it's OD (post-dividers) are
> capable of running at up to 2.97GHz. So switch the divider
> implementation in clk-regmap to clk_ops.determine_rate to support these
> higher frequencies on 32-bit systems.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

Looks good. I see no reason to keep this one as RFC.
I can take it directly if this is OK with you ?

> ---
>  drivers/clk/meson/clk-pll.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
> index 49f27fe53213..9e55617bc3b4 100644
> --- a/drivers/clk/meson/clk-pll.c
> +++ b/drivers/clk/meson/clk-pll.c
> @@ -242,8 +242,8 @@ static int meson_clk_get_pll_settings(unsigned long rate,
>  	return best ? 0 : -EINVAL;
>  }
>  
> -static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
> -				     unsigned long *parent_rate)
> +static int meson_clk_pll_determine_rate(struct clk_hw *hw,
> +					struct clk_rate_request *req)
>  {
>  	struct clk_regmap *clk = to_clk_regmap(hw);
>  	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
> @@ -251,22 +251,26 @@ static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
>  	unsigned long round;
>  	int ret;
>  
> -	ret = meson_clk_get_pll_settings(rate, *parent_rate, &m, &n, pll);
> +	ret = meson_clk_get_pll_settings(req->rate, req->best_parent_rate,
> +					 &m, &n, pll);
>  	if (ret)
> -		return meson_clk_pll_recalc_rate(hw, *parent_rate);
> +		return ret;
>  
> -	round = __pll_params_to_rate(*parent_rate, m, n, 0, pll);
> +	round = __pll_params_to_rate(req->best_parent_rate, m, n, 0, pll);
>  
> -	if (!MESON_PARM_APPLICABLE(&pll->frac) || rate == round)
> -		return round;
> +	if (!MESON_PARM_APPLICABLE(&pll->frac) || req->rate == round) {
> +		req->rate = round;
> +		return 0;
> +	}
>  
>  	/*
>  	 * The rate provided by the setting is not an exact match, let's
>  	 * try to improve the result using the fractional parameter
>  	 */
> -	frac = __pll_params_with_frac(rate, *parent_rate, m, n, pll);
> +	frac = __pll_params_with_frac(req->rate, req->best_parent_rate, m, n, pll);
> +	req->rate = __pll_params_to_rate(req->best_parent_rate, m, n, frac, pll);
>  
> -	return __pll_params_to_rate(*parent_rate, m, n, frac, pll);
> +	return 0;
>  }
>  
>  static int meson_clk_pll_wait_lock(struct clk_hw *hw)
> @@ -419,7 +423,7 @@ static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
>   */
>  const struct clk_ops meson_clk_pcie_pll_ops = {
>  	.recalc_rate	= meson_clk_pll_recalc_rate,
> -	.round_rate	= meson_clk_pll_round_rate,
> +	.determine_rate	= meson_clk_pll_determine_rate,
>  	.is_enabled	= meson_clk_pll_is_enabled,
>  	.enable		= meson_clk_pcie_pll_enable,
>  	.disable	= meson_clk_pll_disable
> @@ -429,7 +433,7 @@ EXPORT_SYMBOL_GPL(meson_clk_pcie_pll_ops);
>  const struct clk_ops meson_clk_pll_ops = {
>  	.init		= meson_clk_pll_init,
>  	.recalc_rate	= meson_clk_pll_recalc_rate,
> -	.round_rate	= meson_clk_pll_round_rate,
> +	.determine_rate	= meson_clk_pll_determine_rate,
>  	.set_rate	= meson_clk_pll_set_rate,
>  	.is_enabled	= meson_clk_pll_is_enabled,
>  	.enable		= meson_clk_pll_enable,
Martin Blumenstingl May 18, 2021, 8:17 p.m. UTC | #2
Hi Jerome,

On Tue, May 18, 2021 at 9:50 AM Jerome Brunet <jbrunet@baylibre.com> wrote:
>
>
> On Mon 17 May 2021 at 22:37, Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote:
>
> > This increases the maxmium supported frequency on 32-bit systems from
> > 2^31 (signed long as used by clk_ops.round_rate, maximum value:
> > approx. 2.14GHz) to 2^32 (unsigned long as used by
> > clk_ops.determine_rate, maximum value: approx. 4.29GHz).
> > On Meson8/8b/8m2 the HDMI PLL and it's OD (post-dividers) are
> > capable of running at up to 2.97GHz. So switch the divider
> > implementation in clk-regmap to clk_ops.determine_rate to support these
> > higher frequencies on 32-bit systems.
> >
> > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
>
> Looks good. I see no reason to keep this one as RFC.
Great, thanks for checking!

> I can take it directly if this is OK with you ?
That would be amazing.
Obviously no objections from my side :-)


Best regards,
Martin
Jerome Brunet May 19, 2021, 3:10 p.m. UTC | #3
On Tue 18 May 2021 at 22:17, Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote:

> Hi Jerome,
>
> On Tue, May 18, 2021 at 9:50 AM Jerome Brunet <jbrunet@baylibre.com> wrote:
>>
>>
>> On Mon 17 May 2021 at 22:37, Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote:
>>
>> > This increases the maxmium supported frequency on 32-bit systems from
>> > 2^31 (signed long as used by clk_ops.round_rate, maximum value:
>> > approx. 2.14GHz) to 2^32 (unsigned long as used by
>> > clk_ops.determine_rate, maximum value: approx. 4.29GHz).
>> > On Meson8/8b/8m2 the HDMI PLL and it's OD (post-dividers) are
>> > capable of running at up to 2.97GHz. So switch the divider
>> > implementation in clk-regmap to clk_ops.determine_rate to support these
>> > higher frequencies on 32-bit systems.
>> >
>> > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
>>
>> Looks good. I see no reason to keep this one as RFC.
> Great, thanks for checking!
>
>> I can take it directly if this is OK with you ?
> That would be amazing.
> Obviously no objections from my side :-)
>
>
> Best regards,
> Martin

Applied then. Thx
diff mbox series

Patch

diff --git a/drivers/clk/meson/clk-pll.c b/drivers/clk/meson/clk-pll.c
index 49f27fe53213..9e55617bc3b4 100644
--- a/drivers/clk/meson/clk-pll.c
+++ b/drivers/clk/meson/clk-pll.c
@@ -242,8 +242,8 @@  static int meson_clk_get_pll_settings(unsigned long rate,
 	return best ? 0 : -EINVAL;
 }
 
-static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
-				     unsigned long *parent_rate)
+static int meson_clk_pll_determine_rate(struct clk_hw *hw,
+					struct clk_rate_request *req)
 {
 	struct clk_regmap *clk = to_clk_regmap(hw);
 	struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
@@ -251,22 +251,26 @@  static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 	unsigned long round;
 	int ret;
 
-	ret = meson_clk_get_pll_settings(rate, *parent_rate, &m, &n, pll);
+	ret = meson_clk_get_pll_settings(req->rate, req->best_parent_rate,
+					 &m, &n, pll);
 	if (ret)
-		return meson_clk_pll_recalc_rate(hw, *parent_rate);
+		return ret;
 
-	round = __pll_params_to_rate(*parent_rate, m, n, 0, pll);
+	round = __pll_params_to_rate(req->best_parent_rate, m, n, 0, pll);
 
-	if (!MESON_PARM_APPLICABLE(&pll->frac) || rate == round)
-		return round;
+	if (!MESON_PARM_APPLICABLE(&pll->frac) || req->rate == round) {
+		req->rate = round;
+		return 0;
+	}
 
 	/*
 	 * The rate provided by the setting is not an exact match, let's
 	 * try to improve the result using the fractional parameter
 	 */
-	frac = __pll_params_with_frac(rate, *parent_rate, m, n, pll);
+	frac = __pll_params_with_frac(req->rate, req->best_parent_rate, m, n, pll);
+	req->rate = __pll_params_to_rate(req->best_parent_rate, m, n, frac, pll);
 
-	return __pll_params_to_rate(*parent_rate, m, n, frac, pll);
+	return 0;
 }
 
 static int meson_clk_pll_wait_lock(struct clk_hw *hw)
@@ -419,7 +423,7 @@  static int meson_clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
  */
 const struct clk_ops meson_clk_pcie_pll_ops = {
 	.recalc_rate	= meson_clk_pll_recalc_rate,
-	.round_rate	= meson_clk_pll_round_rate,
+	.determine_rate	= meson_clk_pll_determine_rate,
 	.is_enabled	= meson_clk_pll_is_enabled,
 	.enable		= meson_clk_pcie_pll_enable,
 	.disable	= meson_clk_pll_disable
@@ -429,7 +433,7 @@  EXPORT_SYMBOL_GPL(meson_clk_pcie_pll_ops);
 const struct clk_ops meson_clk_pll_ops = {
 	.init		= meson_clk_pll_init,
 	.recalc_rate	= meson_clk_pll_recalc_rate,
-	.round_rate	= meson_clk_pll_round_rate,
+	.determine_rate	= meson_clk_pll_determine_rate,
 	.set_rate	= meson_clk_pll_set_rate,
 	.is_enabled	= meson_clk_pll_is_enabled,
 	.enable		= meson_clk_pll_enable,