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[v2,00/15] UFS: Add OPP and interconnect support

Message ID 20230720054100.9940-1-manivannan.sadhasivam@linaro.org (mailing list archive)
Headers show
Series UFS: Add OPP and interconnect support | expand

Message

Manivannan Sadhasivam July 20, 2023, 5:40 a.m. UTC
Hi,

This series adds OPP (Operating Points) support to UFSHCD driver and
interconnect support to Qcom UFS driver.

Motivation behind adding OPP support is to scale both clocks as well as
regulators/performance state dynamically. Currently, UFSHCD just scales
clock frequency during runtime with the help of "freq-table-hz" property
defined in devicetree. With the addition of OPP tables in devicetree (as
done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
both clocks and performance state of power domain which helps in power
saving.

For the addition of OPP support to UFSHCD, there are changes required to
the OPP framework and devfreq drivers which are also added in this series.

Finally, interconnect support is added to Qcom UFS driver for scaling the
interconnect path dynamically. This is required to avoid boot crash in
recent SoCs and also to save power during runtime. More information is
available in patch 13/13.

Credits
=======

This series is a continuation of previous work by Krzysztof Kozlowski [1]
and Brian Masney [2]. Ideally, this could've split into two series (OPP
and interconnect) but since there will be a dependency in the devicetree,
I decided to keep them in a single series.

Testing
=======

This series is tested on 96Boards RB3 (SDM845 SoC) and RB5 (SM8250 SoC)
development boards.

Merging Strategy
================

An immutable branch might be required between OPP and SCSI trees because of
the API dependency (devfreq too). And I leave it up to the maintainers to
decide.

Thanks,
Mani

[1] https://lore.kernel.org/all/20220513061347.46480-1-krzysztof.kozlowski@linaro.org/
[2] https://lore.kernel.org/all/20221117104957.254648-1-bmasney@redhat.com/

Changes in v2:

* Added more description to the bindings patch 2/15
* Fixed dev_pm_opp_put() usage in patch 10/15
* Added a new patch for adding enums for UFS lanes 14/15
* Changed the icc variables to mem_bw and cfg_bw and used
  the enums for gears and lanes in bw_table
* Collected review tags
* Added SCSI list and folks
* Removed duplicate patches

Krzysztof Kozlowski (2):
  dt-bindings: ufs: common: add OPP table
  arm64: dts: qcom: sdm845: Add OPP table support to UFSHC

Manivannan Sadhasivam (13):
  dt-bindings: opp: Increase maxItems for opp-hz property
  arm64: dts: qcom: sdm845: Add missing RPMh power domain to GCC
  arm64: dts: qcom: sdm845: Fix the min frequency of "ice_core_clk"
  arm64: dts: qcom: sm8250: Add OPP table support to UFSHC
  OPP: Introduce dev_pm_opp_find_freq_{ceil/floor}_indexed() APIs
  OPP: Introduce dev_pm_opp_get_freq_indexed() API
  PM / devfreq: Switch to dev_pm_opp_find_freq_{ceil/floor}_indexed()
    APIs
  scsi: ufs: core: Add OPP support for scaling clocks and regulators
  scsi: ufs: host: Add support for parsing OPP
  arm64: dts: qcom: sdm845: Add interconnect paths to UFSHC
  arm64: dts: qcom: sm8250: Add interconnect paths to UFSHC
  scsi: ufs: core: Add enums for UFS lanes
  scsi: ufs: qcom: Add support for scaling interconnects

 .../devicetree/bindings/opp/opp-v2-base.yaml  |   2 +-
 .../devicetree/bindings/ufs/ufs-common.yaml   |  34 +++-
 arch/arm64/boot/dts/qcom/sdm845.dtsi          |  47 ++++--
 arch/arm64/boot/dts/qcom/sm8250.dtsi          |  43 +++--
 drivers/devfreq/devfreq.c                     |  14 +-
 drivers/opp/core.c                            |  76 +++++++++
 drivers/ufs/core/ufshcd.c                     | 148 +++++++++++++-----
 drivers/ufs/host/ufs-qcom.c                   | 131 +++++++++++++++-
 drivers/ufs/host/ufs-qcom.h                   |   3 +
 drivers/ufs/host/ufshcd-pltfrm.c              | 120 +++++++++++++-
 include/linux/pm_opp.h                        |  26 +++
 include/ufs/ufshcd.h                          |   4 +
 include/ufs/unipro.h                          |   6 +
 13 files changed, 586 insertions(+), 68 deletions(-)

Comments

Bart Van Assche July 20, 2023, 4:44 p.m. UTC | #1
On 7/19/23 22:40, Manivannan Sadhasivam wrote:
> This series adds OPP (Operating Points) support to UFSHCD driver and
> interconnect support to Qcom UFS driver.
> 
> Motivation behind adding OPP support is to scale both clocks as well as
> regulators/performance state dynamically. Currently, UFSHCD just scales
> clock frequency during runtime with the help of "freq-table-hz" property
> defined in devicetree. With the addition of OPP tables in devicetree (as
> done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> both clocks and performance state of power domain which helps in power
> saving.
> 
> For the addition of OPP support to UFSHCD, there are changes required to
> the OPP framework and devfreq drivers which are also added in this series.
> 
> Finally, interconnect support is added to Qcom UFS driver for scaling the
> interconnect path dynamically. This is required to avoid boot crash in
> recent SoCs and also to save power during runtime. More information is
> available in patch 13/13.

How much power can OPP save? I'm asking this since I'm wondering whether
the power saved by OPP outweighs the complexity added by this patch series.

Thanks,

Bart.
Manivannan Sadhasivam July 20, 2023, 4:57 p.m. UTC | #2
On Thu, Jul 20, 2023 at 09:44:38AM -0700, Bart Van Assche wrote:
> On 7/19/23 22:40, Manivannan Sadhasivam wrote:
> > This series adds OPP (Operating Points) support to UFSHCD driver and
> > interconnect support to Qcom UFS driver.
> > 
> > Motivation behind adding OPP support is to scale both clocks as well as
> > regulators/performance state dynamically. Currently, UFSHCD just scales
> > clock frequency during runtime with the help of "freq-table-hz" property
> > defined in devicetree. With the addition of OPP tables in devicetree (as
> > done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> > both clocks and performance state of power domain which helps in power
> > saving.
> > 
> > For the addition of OPP support to UFSHCD, there are changes required to
> > the OPP framework and devfreq drivers which are also added in this series.
> > 
> > Finally, interconnect support is added to Qcom UFS driver for scaling the
> > interconnect path dynamically. This is required to avoid boot crash in
> > recent SoCs and also to save power during runtime. More information is
> > available in patch 13/13.
> 
> How much power can OPP save? I'm asking this since I'm wondering whether
> the power saved by OPP outweighs the complexity added by this patch series.
> 

I haven't had a chance to do proper power measurements with this series due to
lack of access to tools. But it won't be optimal to run the clocks at high/low
frequencies without changing the associated regulator/power domain state.

Atleast on Qcom platforms, the clock frequencies are tied to RPMh (power
management entity) performance states for the peripherals. So both have to go
hand in hand. Till now, only UFS among the other peripherals is not doing it
right and hence this series.

- Mani

> Thanks,
> 
> Bart.
Viresh Kumar July 21, 2023, 9:42 a.m. UTC | #3
On 20-07-23, 11:10, Manivannan Sadhasivam wrote:
> Hi,
> 
> This series adds OPP (Operating Points) support to UFSHCD driver and
> interconnect support to Qcom UFS driver.
> 
> Motivation behind adding OPP support is to scale both clocks as well as
> regulators/performance state dynamically. Currently, UFSHCD just scales
> clock frequency during runtime with the help of "freq-table-hz" property
> defined in devicetree. With the addition of OPP tables in devicetree (as
> done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> both clocks and performance state of power domain which helps in power
> saving.
> 
> For the addition of OPP support to UFSHCD, there are changes required to
> the OPP framework and devfreq drivers which are also added in this series.
> 
> Finally, interconnect support is added to Qcom UFS driver for scaling the
> interconnect path dynamically. This is required to avoid boot crash in
> recent SoCs and also to save power during runtime. More information is
> available in patch 13/13.

Hi Mani,

I have picked the OPP related patches from here (apart from DT one)
and sent them separately in a series, along with few changes from me.
Also pushed them in my linux-next branch.

Thanks.
Manivannan Sadhasivam July 21, 2023, 11:54 a.m. UTC | #4
On Fri, Jul 21, 2023 at 03:12:06PM +0530, Viresh Kumar wrote:
> On 20-07-23, 11:10, Manivannan Sadhasivam wrote:
> > Hi,
> > 
> > This series adds OPP (Operating Points) support to UFSHCD driver and
> > interconnect support to Qcom UFS driver.
> > 
> > Motivation behind adding OPP support is to scale both clocks as well as
> > regulators/performance state dynamically. Currently, UFSHCD just scales
> > clock frequency during runtime with the help of "freq-table-hz" property
> > defined in devicetree. With the addition of OPP tables in devicetree (as
> > done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> > both clocks and performance state of power domain which helps in power
> > saving.
> > 
> > For the addition of OPP support to UFSHCD, there are changes required to
> > the OPP framework and devfreq drivers which are also added in this series.
> > 
> > Finally, interconnect support is added to Qcom UFS driver for scaling the
> > interconnect path dynamically. This is required to avoid boot crash in
> > recent SoCs and also to save power during runtime. More information is
> > available in patch 13/13.
> 
> Hi Mani,
> 
> I have picked the OPP related patches from here (apart from DT one)
> and sent them separately in a series, along with few changes from me.
> Also pushed them in my linux-next branch.
> 

Thanks Viresh! For patch 8/15, Kbuild bot has identified one potential null ptr
dereference issue. Could you please fix that in your branch?

You just need to remove the opp dereference in dev_pm_opp_get_freq_indexed()
before the IS_ERR_OR_NULL() check as below:

```
diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 66dc0d0cfaed..683e6e61f80b 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -208,9 +208,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
  */
 unsigned long dev_pm_opp_get_freq_indexed(struct dev_pm_opp *opp, u32 index)
 {
-       struct opp_table *opp_table = opp->opp_table;
-
-       if (IS_ERR_OR_NULL(opp) || index >= opp_table->clk_count) {
+       if (IS_ERR_OR_NULL(opp) || index >= opp->opp_table->clk_count) {
                pr_err("%s: Invalid parameters\n", __func__);
                return 0;
        }
```

- Mani

> Thanks.
> 
> -- 
> viresh
Bjorn Andersson July 22, 2023, 5:17 a.m. UTC | #5
On Thu, 20 Jul 2023 11:10:45 +0530, Manivannan Sadhasivam wrote:
> This series adds OPP (Operating Points) support to UFSHCD driver and
> interconnect support to Qcom UFS driver.
> 
> Motivation behind adding OPP support is to scale both clocks as well as
> regulators/performance state dynamically. Currently, UFSHCD just scales
> clock frequency during runtime with the help of "freq-table-hz" property
> defined in devicetree. With the addition of OPP tables in devicetree (as
> done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> both clocks and performance state of power domain which helps in power
> saving.
> 
> [...]

Applied, thanks!

[03/15] arm64: dts: qcom: sdm845: Add missing RPMh power domain to GCC
        commit: 4b6ea15c0a1122422b44bf6c47a3c22fc8d46777
[04/15] arm64: dts: qcom: sdm845: Fix the min frequency of "ice_core_clk"
        commit: bbbef6e24bc4493602df68b052f6f48d48e3184a
[12/15] arm64: dts: qcom: sdm845: Add interconnect paths to UFSHC
        commit: 84e2e371f4f911337604e8ba9281e950230d1189
[13/15] arm64: dts: qcom: sm8250: Add interconnect paths to UFSHC
        commit: aeea56072cc8cb0af2b35798aa7d72047f4c8ffa

Best regards,
Viresh Kumar July 24, 2023, 7:52 a.m. UTC | #6
On 21-07-23, 17:24, Manivannan Sadhasivam wrote:
> On Fri, Jul 21, 2023 at 03:12:06PM +0530, Viresh Kumar wrote:
> > On 20-07-23, 11:10, Manivannan Sadhasivam wrote:
> > > Hi,
> > > 
> > > This series adds OPP (Operating Points) support to UFSHCD driver and
> > > interconnect support to Qcom UFS driver.
> > > 
> > > Motivation behind adding OPP support is to scale both clocks as well as
> > > regulators/performance state dynamically. Currently, UFSHCD just scales
> > > clock frequency during runtime with the help of "freq-table-hz" property
> > > defined in devicetree. With the addition of OPP tables in devicetree (as
> > > done for Qcom SDM845 and SM8250 SoCs in this series) UFSHCD can now scale
> > > both clocks and performance state of power domain which helps in power
> > > saving.
> > > 
> > > For the addition of OPP support to UFSHCD, there are changes required to
> > > the OPP framework and devfreq drivers which are also added in this series.
> > > 
> > > Finally, interconnect support is added to Qcom UFS driver for scaling the
> > > interconnect path dynamically. This is required to avoid boot crash in
> > > recent SoCs and also to save power during runtime. More information is
> > > available in patch 13/13.
> > 
> > Hi Mani,
> > 
> > I have picked the OPP related patches from here (apart from DT one)
> > and sent them separately in a series, along with few changes from me.
> > Also pushed them in my linux-next branch.
> > 
> 
> Thanks Viresh! For patch 8/15, Kbuild bot has identified one potential null ptr
> dereference issue. Could you please fix that in your branch?
> 
> You just need to remove the opp dereference in dev_pm_opp_get_freq_indexed()
> before the IS_ERR_OR_NULL() check as below:
> 
> ```
> diff --git a/drivers/opp/core.c b/drivers/opp/core.c
> index 66dc0d0cfaed..683e6e61f80b 100644
> --- a/drivers/opp/core.c
> +++ b/drivers/opp/core.c
> @@ -208,9 +208,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
>   */
>  unsigned long dev_pm_opp_get_freq_indexed(struct dev_pm_opp *opp, u32 index)
>  {
> -       struct opp_table *opp_table = opp->opp_table;
> -
> -       if (IS_ERR_OR_NULL(opp) || index >= opp_table->clk_count) {
> +       if (IS_ERR_OR_NULL(opp) || index >= opp->opp_table->clk_count) {
>                 pr_err("%s: Invalid parameters\n", __func__);
>                 return 0;
>         }

Fixed.