diff mbox series

[V3,04/15] cpufreq: mediatek: Record previous target vproc value

Message ID 20220415055916.28350-5-rex-bc.chen@mediatek.com (mailing list archive)
State New, archived
Headers show
Series cpufreq: mediatek: Cleanup and support MT8183 and MT8186 | expand

Commit Message

Rex-BC Chen (陳柏辰) April 15, 2022, 5:59 a.m. UTC
From: Jia-Wei Chang <jia-wei.chang@mediatek.com>

We found the buck voltage may not be exactly the same with what we set
because CPU may share the same buck with other module.
Therefore, we need to record the previous desired value instead of reading
it from regulators.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

Comments

AngeloGioacchino Del Regno April 15, 2022, 12:24 p.m. UTC | #1
Il 15/04/22 07:59, Rex-BC Chen ha scritto:
> From: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> 
> We found the buck voltage may not be exactly the same with what we set
> because CPU may share the same buck with other module.
> Therefore, we need to record the previous desired value instead of reading
> it from regulators.
> 
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
> ---
>   drivers/cpufreq/mediatek-cpufreq.c | 17 +++++++++++++----
>   1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
> index ff27f77e8ee6..fa8b193bf27b 100644
> --- a/drivers/cpufreq/mediatek-cpufreq.c
> +++ b/drivers/cpufreq/mediatek-cpufreq.c
> @@ -40,6 +40,7 @@ struct mtk_cpu_dvfs_info {
>   	struct list_head list_head;
>   	int intermediate_voltage;
>   	bool need_voltage_tracking;
> +	int pre_vproc;
>   };
>   
>   static LIST_HEAD(dvfs_info_list);
> @@ -191,11 +192,17 @@ static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
>   
>   static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc)
>   {
> +	int ret;
> +
>   	if (info->need_voltage_tracking)
> -		return mtk_cpufreq_voltage_tracking(info, vproc);
> +		ret = mtk_cpufreq_voltage_tracking(info, vproc);
>   	else
> -		return regulator_set_voltage(info->proc_reg, vproc,
> -					     vproc + VOLT_TOL);
> +		ret = regulator_set_voltage(info->proc_reg, vproc,
> +					    MAX_VOLT_LIMIT);
> +	if (!ret)
> +		info->pre_vproc = vproc;
> +
> +	return ret;
>   }
>   
>   static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
> @@ -213,7 +220,9 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
>   	inter_vproc = info->intermediate_voltage;
>   
>   	pre_freq_hz = clk_get_rate(cpu_clk);
> -	pre_vproc = regulator_get_voltage(info->proc_reg);
> +	pre_vproc = info->pre_vproc;
> +	if (pre_vproc <= 0)
> +		pre_vproc = regulator_get_voltage(info->proc_reg);

I would do it like that, instead:

	if (unlikely(info->pre_vproc <= 0))
		pre_vproc = regulator_get_voltage(info->proc_reg);
	else
		pre_vproc = info->pre_vproc;

....as even though it is indeed possible that info->pre_vproc is <= 0, it is
very unlikely to happen ;-)
This also solves a 'pre_vproc' double assignment issue, by the way.

Cheers,
Angelo
Rex-BC Chen (陳柏辰) April 18, 2022, 1:37 a.m. UTC | #2
On Fri, 2022-04-15 at 14:24 +0200, AngeloGioacchino Del Regno wrote:
> Il 15/04/22 07:59, Rex-BC Chen ha scritto:
> > From: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> > 
> > We found the buck voltage may not be exactly the same with what we
> > set
> > because CPU may share the same buck with other module.
> > Therefore, we need to record the previous desired value instead of
> > reading
> > it from regulators.
> > 
> > Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> > Signed-off-by: Jia-Wei Chang <jia-wei.chang@mediatek.com>
> > Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
> > ---
> >   drivers/cpufreq/mediatek-cpufreq.c | 17 +++++++++++++----
> >   1 file changed, 13 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/cpufreq/mediatek-cpufreq.c
> > b/drivers/cpufreq/mediatek-cpufreq.c
> > index ff27f77e8ee6..fa8b193bf27b 100644
> > --- a/drivers/cpufreq/mediatek-cpufreq.c
> > +++ b/drivers/cpufreq/mediatek-cpufreq.c
> > @@ -40,6 +40,7 @@ struct mtk_cpu_dvfs_info {
> >   	struct list_head list_head;
> >   	int intermediate_voltage;
> >   	bool need_voltage_tracking;
> > +	int pre_vproc;
> >   };
> >   
> >   static LIST_HEAD(dvfs_info_list);
> > @@ -191,11 +192,17 @@ static int
> > mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
> >   
> >   static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info
> > *info, int vproc)
> >   {
> > +	int ret;
> > +
> >   	if (info->need_voltage_tracking)
> > -		return mtk_cpufreq_voltage_tracking(info, vproc);
> > +		ret = mtk_cpufreq_voltage_tracking(info, vproc);
> >   	else
> > -		return regulator_set_voltage(info->proc_reg, vproc,
> > -					     vproc + VOLT_TOL);
> > +		ret = regulator_set_voltage(info->proc_reg, vproc,
> > +					    MAX_VOLT_LIMIT);
> > +	if (!ret)
> > +		info->pre_vproc = vproc;
> > +
> > +	return ret;
> >   }
> >   
> >   static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
> > @@ -213,7 +220,9 @@ static int mtk_cpufreq_set_target(struct
> > cpufreq_policy *policy,
> >   	inter_vproc = info->intermediate_voltage;
> >   
> >   	pre_freq_hz = clk_get_rate(cpu_clk);
> > -	pre_vproc = regulator_get_voltage(info->proc_reg);
> > +	pre_vproc = info->pre_vproc;
> > +	if (pre_vproc <= 0)
> > +		pre_vproc = regulator_get_voltage(info->proc_reg);
> 
> I would do it like that, instead:
> 
> 	if (unlikely(info->pre_vproc <= 0))
> 		pre_vproc = regulator_get_voltage(info->proc_reg);
> 	else
> 		pre_vproc = info->pre_vproc;
> 
> ....as even though it is indeed possible that info->pre_vproc is <=
> 0, it is
> very unlikely to happen ;-)
> This also solves a 'pre_vproc' double assignment issue, by the way.
> 
> Cheers,
> Angelo
> 
> 
> 

Hello Angelo,

OK, I will add this in next version.
Thanks for your suggestion.

BRs,
Rex
diff mbox series

Patch

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index ff27f77e8ee6..fa8b193bf27b 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -40,6 +40,7 @@  struct mtk_cpu_dvfs_info {
 	struct list_head list_head;
 	int intermediate_voltage;
 	bool need_voltage_tracking;
+	int pre_vproc;
 };
 
 static LIST_HEAD(dvfs_info_list);
@@ -191,11 +192,17 @@  static int mtk_cpufreq_voltage_tracking(struct mtk_cpu_dvfs_info *info,
 
 static int mtk_cpufreq_set_voltage(struct mtk_cpu_dvfs_info *info, int vproc)
 {
+	int ret;
+
 	if (info->need_voltage_tracking)
-		return mtk_cpufreq_voltage_tracking(info, vproc);
+		ret = mtk_cpufreq_voltage_tracking(info, vproc);
 	else
-		return regulator_set_voltage(info->proc_reg, vproc,
-					     vproc + VOLT_TOL);
+		ret = regulator_set_voltage(info->proc_reg, vproc,
+					    MAX_VOLT_LIMIT);
+	if (!ret)
+		info->pre_vproc = vproc;
+
+	return ret;
 }
 
 static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
@@ -213,7 +220,9 @@  static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 	inter_vproc = info->intermediate_voltage;
 
 	pre_freq_hz = clk_get_rate(cpu_clk);
-	pre_vproc = regulator_get_voltage(info->proc_reg);
+	pre_vproc = info->pre_vproc;
+	if (pre_vproc <= 0)
+		pre_vproc = regulator_get_voltage(info->proc_reg);
 	if (pre_vproc < 0) {
 		dev_err(cpu_dev, "invalid Vproc value: %d\n", pre_vproc);
 		return pre_vproc;