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[V4,00/14] cpufreq: mediatek: Cleanup and support MT8183 and MT8186

Message ID 20220422075239.16437-1-rex-bc.chen@mediatek.com (mailing list archive)
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Series cpufreq: mediatek: Cleanup and support MT8183 and MT8186 | expand

Message

Rex-BC Chen (陳柏辰) April 22, 2022, 7:52 a.m. UTC
Cpufreq is a DVFS driver used for power saving to scale the clock frequency
and supply the voltage for CPUs. This series do some cleanup for MediaTek
cpufreq drivers and add support for MediaTek SVS[2] and MediaTek CCI
devfreq[3] which are supported in MT8183 and MT8186.

Changes for V4:
1. Revise drivers from reviewers' suggestion.
2. Fix name of opp table issue.

Changes for V3:
1. Rebased to linux-next-20220414.
2. Drop accepted patches.
3. Drop "cpufreq: mediatek: Use maximum voltage in init stage" because we
   make sure the voltage we set is safe for both mediatek cci and cpufreq.
4. Rename cci property to mediatek,cci.
5. Adjust order of cleanup patches.
6. Add new patches for cleanup, handle infinite loop and MT8183 dts.
7. Revise drivers from reviewers' suggestion.
8. Revise commit message of some patches to avoid confusion and misunderstand.
9. Revise "cpufreq: mediatek: Link CCI device to CPU".
   We do not return successful to pretend we set the target frequency done
   when cci is not ready. Instead, we find and set a safe voltage so that we
   can set the target cpufrequency.

Changes for V2:
1. Drop the modification of transforming cpufreq-mediatek into yaml and
   only add the MediaTek CCI property for MediaTek cpufreq.
2. Split the original patches into several patches.

Reference series:
[1]: V1 of this series is present by Jia-Wei Chang.
     message-id:20220307122151.11666-1-jia-wei.chang@mediatek.com

[2]: The MediaTek CCI devfreq driver is introduced in another series.
     message-id:20220408052150.22536-1-johnson.wang@mediatek.com

[3]: The MediaTek SVS driver is introduced in another series.
     message-id:20220221063939.14969-1-roger.lu@mediatek.com

Andrew-sh.Cheng (1):
  cpufreq: mediatek: Add opp notification support

Jia-Wei Chang (6):
  cpufreq: mediatek: Record previous target vproc value
  cpufreq: mediatek: Move voltage limits to platform data
  cpufreq: mediatek: Add .get function
  cpufreq: mediatek: Make sram regulator optional
  cpufreq: mediatek: Refine mtk_cpufreq_voltage_tracking()
  cpufreq: mediatek: Add support for MT8186

Rex-BC Chen (7):
  dt-bindings: cpufreq: mediatek: Add MediaTek CCI property
  cpufreq: mediatek: Use device print to show logs
  cpufreq: mediatek: Replace old_* with pre_*
  cpufreq: mediatek: Link CCI device to CPU
  arm64: dts: mediatek: Add opp table and clock property for MT8183 cpufreq
  arm64: dts: mediatek: Add MediaTek CCI node for MT8183
  arm64: dts: mediatek: Add mediatek,cci property for MT8183 cpufreq

 .../bindings/cpufreq/cpufreq-mediatek.txt     |   5 +
 arch/arm64/boot/dts/mediatek/mt8183-evb.dts   |  36 ++
 .../arm64/boot/dts/mediatek/mt8183-kukui.dtsi |   4 +
 arch/arm64/boot/dts/mediatek/mt8183.dtsi      | 285 ++++++++++
 drivers/cpufreq/mediatek-cpufreq.c            | 504 ++++++++++++------
 5 files changed, 670 insertions(+), 164 deletions(-)

Comments

Krzysztof Kozlowski April 22, 2022, 5:23 p.m. UTC | #1
On 22/04/2022 09:52, Rex-BC Chen wrote:
> 
> Reference series:
> [1]: V1 of this series is present by Jia-Wei Chang.
>      message-id:20220307122151.11666-1-jia-wei.chang@mediatek.com
> 
> [2]: The MediaTek CCI devfreq driver is introduced in another series.
>      message-id:20220408052150.22536-1-johnson.wang@mediatek.com
> 
> [3]: The MediaTek SVS driver is introduced in another series.
>      message-id:20220221063939.14969-1-roger.lu@mediatek.com

These are not proper links. Please use lore references.


Best regards,
Krzysztof
Viresh Kumar April 25, 2022, 5:20 a.m. UTC | #2
On 22-04-22, 15:52, Rex-BC Chen wrote:
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> 
> >From this opp notifier, cpufreq should listen to opp notification and do

Why the extra ">" here ?

> proper actions when receiving events of disable and voltage adjustment.
> 
> One of the user for this opp notifier is MediaTek SVS.
> The MediaTek Smart Voltage Scaling (SVS) is a hardware which calculates
> suitable SVS bank voltages to OPP voltage table.
> 
> 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>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  drivers/cpufreq/mediatek-cpufreq.c | 92 +++++++++++++++++++++++++++---
>  1 file changed, 84 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
> +static int mtk_cpufreq_opp_notifier(struct notifier_block *nb,
> +				    unsigned long event, void *data)
> +{
> +	struct dev_pm_opp *opp = data;
> +	struct dev_pm_opp *new_opp;
> +	struct mtk_cpu_dvfs_info *info;
> +	unsigned long freq, volt;
> +	struct cpufreq_policy *policy;
> +	int ret = 0;
> +
> +	info = container_of(nb, struct mtk_cpu_dvfs_info, opp_nb);
> +
> +	if (event == OPP_EVENT_ADJUST_VOLTAGE) {

I don't see any call to dev_pm_opp_adjust_voltage() for your platform, how is
this ever going to get called ?

> +		freq = dev_pm_opp_get_freq(opp);
> +
> +		mutex_lock(&info->reg_lock);
> +		if (info->opp_freq == freq) {
> +			volt = dev_pm_opp_get_voltage(opp);
> +			ret = mtk_cpufreq_set_voltage(info, volt);
> +			if (ret)
> +				dev_err(info->cpu_dev,
> +					"failed to scale voltage: %d\n", ret);
> +		}
> +		mutex_unlock(&info->reg_lock);
> +	} else if (event == OPP_EVENT_DISABLE) {
> +		freq = dev_pm_opp_get_freq(opp);
> +
> +		/* case of current opp item is disabled */
> +		if (info->opp_freq == freq) {
> +			freq = 1;
> +			new_opp = dev_pm_opp_find_freq_ceil(info->cpu_dev,
> +							    &freq);
> +			if (IS_ERR(new_opp)) {
> +				dev_err(info->cpu_dev,
> +					"all opp items are disabled\n");
> +				ret = PTR_ERR(new_opp);
> +				return notifier_from_errno(ret);
> +			}
> +
> +			dev_pm_opp_put(new_opp);
> +			policy = cpufreq_cpu_get(info->opp_cpu);
> +			if (policy) {
> +				cpufreq_driver_target(policy, freq / 1000,
> +						      CPUFREQ_RELATION_L);
> +				cpufreq_cpu_put(policy);

IIUC, then you are trying to change the frequency if a currently used OPP is
getting removed ? In that case, this problem is generic enough not to be fixed
in a end driver. This should be fixed in core somehow.
Rex-BC Chen (陳柏辰) April 25, 2022, 6:20 a.m. UTC | #3
On Fri, 2022-04-22 at 19:23 +0200, Krzysztof Kozlowski wrote:
> On 22/04/2022 09:52, Rex-BC Chen wrote:
> > 
> > Reference series:
> > [1]: V1 of this series is present by Jia-Wei Chang.
> >      message-id:20220307122151.11666-1-jia-wei.chang@mediatek.com
> > 
> > [2]: The MediaTek CCI devfreq driver is introduced in another
> > series.
> >      message-id:20220408052150.22536-1-johnson.wang@mediatek.com
> > 
> > [3]: The MediaTek SVS driver is introduced in another series.
> >      message-id:20220221063939.14969-1-roger.lu@mediatek.com
> 
> These are not proper links. Please use lore references.
> 
> 
> Best regards,
> Krzysztof

Hello Krzysztof,

I will use lore references in next version.
Thanks.

BRs,
Rex