2020-06-04 11:21:59

by Pradeep P V K

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Subject: [PATCH V2 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

Interconnect bandwidth scaling support is now added as a
part of OPP [1]. So, make sure interconnect driver is ready
before handling interconnect scaling.

This change is based on
[1] [Patch v8] Introduce OPP bandwidth bindings
(https://lkml.org/lkml/2020/5/12/493)

[2] [Patch v3] mmc: sdhci-msm: Fix error handling
for dev_pm_opp_of_add_table()
(https://lkml.org/lkml/2020/5/5/491)

Signed-off-by: Pradeep P V K <[email protected]>
---
drivers/mmc/host/sdhci-msm.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index b277dd7..a13ff1b 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -14,6 +14,7 @@
#include <linux/slab.h>
#include <linux/iopoll.h>
#include <linux/regulator/consumer.h>
+#include <linux/interconnect.h>

#include "sdhci-pltfm.h"
#include "cqhci.h"
@@ -2070,6 +2071,18 @@ static int sdhci_msm_probe(struct platform_device *pdev)
}
msm_host->bulk_clks[0].clk = clk;

+ /* Make sure that ICC driver is ready for interconnect bandwdith
+ * scaling before registering the device for OPP.
+ */
+ ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
+ if (ret) {
+ if (ret == -EPROBE_DEFER)
+ dev_info(&pdev->dev, "defer icc path: %d\n", ret);
+ else
+ dev_err(&pdev->dev, "failed to get icc path:%d\n", ret);
+ goto bus_clk_disable;
+ }
+
msm_host->opp_table = dev_pm_opp_set_clkname(&pdev->dev, "core");
if (IS_ERR(msm_host->opp_table)) {
ret = PTR_ERR(msm_host->opp_table);
--
1.9.1


2020-06-04 18:58:23

by Matthias Kaehlcke

[permalink] [raw]
Subject: Re: [PATCH V2 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

On Thu, Jun 04, 2020 at 04:44:42PM +0530, Pradeep P V K wrote:
> Interconnect bandwidth scaling support is now added as a
> part of OPP [1]. So, make sure interconnect driver is ready
> before handling interconnect scaling.
>
> This change is based on
> [1] [Patch v8] Introduce OPP bandwidth bindings
> (https://lkml.org/lkml/2020/5/12/493)
>
> [2] [Patch v3] mmc: sdhci-msm: Fix error handling
> for dev_pm_opp_of_add_table()
> (https://lkml.org/lkml/2020/5/5/491)
>
> Signed-off-by: Pradeep P V K <[email protected]>
> ---
> drivers/mmc/host/sdhci-msm.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index b277dd7..a13ff1b 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -14,6 +14,7 @@
> #include <linux/slab.h>
> #include <linux/iopoll.h>
> #include <linux/regulator/consumer.h>
> +#include <linux/interconnect.h>
>
> #include "sdhci-pltfm.h"
> #include "cqhci.h"
> @@ -2070,6 +2071,18 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> }
> msm_host->bulk_clks[0].clk = clk;
>
> + /* Make sure that ICC driver is ready for interconnect bandwdith
> + * scaling before registering the device for OPP.
> + */
> + ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
> + if (ret) {
> + if (ret == -EPROBE_DEFER)
> + dev_info(&pdev->dev, "defer icc path: %d\n", ret);

I already commented on this on v1:

This log seems to add little more than noise, or are there particular reasons
why it is useful in this driver? Most drivers just return silently in case of
deferred probing.

If you think the log is really needed please explain why.

2020-06-04 22:24:36

by Sibi Sankar

[permalink] [raw]
Subject: Re: [PATCH V2 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

On 2020-06-04 22:39, Matthias Kaehlcke wrote:
> On Thu, Jun 04, 2020 at 04:44:42PM +0530, Pradeep P V K wrote:
>> Interconnect bandwidth scaling support is now added as a
>> part of OPP [1]. So, make sure interconnect driver is ready
>> before handling interconnect scaling.
>>
>> This change is based on
>> [1] [Patch v8] Introduce OPP bandwidth bindings
>> (https://lkml.org/lkml/2020/5/12/493)
>>
>> [2] [Patch v3] mmc: sdhci-msm: Fix error handling
>> for dev_pm_opp_of_add_table()
>> (https://lkml.org/lkml/2020/5/5/491)
>>
>> Signed-off-by: Pradeep P V K <[email protected]>
>> ---
>> drivers/mmc/host/sdhci-msm.c | 13 +++++++++++++
>> 1 file changed, 13 insertions(+)
>>
>> diff --git a/drivers/mmc/host/sdhci-msm.c
>> b/drivers/mmc/host/sdhci-msm.c
>> index b277dd7..a13ff1b 100644
>> --- a/drivers/mmc/host/sdhci-msm.c
>> +++ b/drivers/mmc/host/sdhci-msm.c
>> @@ -14,6 +14,7 @@
>> #include <linux/slab.h>
>> #include <linux/iopoll.h>
>> #include <linux/regulator/consumer.h>
>> +#include <linux/interconnect.h>
>>
>> #include "sdhci-pltfm.h"
>> #include "cqhci.h"
>> @@ -2070,6 +2071,18 @@ static int sdhci_msm_probe(struct
>> platform_device *pdev)
>> }
>> msm_host->bulk_clks[0].clk = clk;
>>
>> + /* Make sure that ICC driver is ready for interconnect bandwdith
>> + * scaling before registering the device for OPP.
>> + */
>> + ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
>> + if (ret) {
>> + if (ret == -EPROBE_DEFER)
>> + dev_info(&pdev->dev, "defer icc path: %d\n", ret);
>
> I already commented on this on v1:
>
> This log seems to add little more than noise, or are there particular
> reasons
> why it is useful in this driver? Most drivers just return silently in
> case of
> deferred probing.
>
> If you think the log is really needed please explain why.

Both the err logs seem redundant.
EPROBE_DEFERS are rather readily
noticeable through the return val.
dev_.._find_icc_paths already prints
err messages when we fail to get icc
paths.


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

2020-06-05 08:11:12

by Pradeep P V K

[permalink] [raw]
Subject: Re: [PATCH V2 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

On 2020-06-05 00:04, Sibi Sankar wrote:
> On 2020-06-04 22:39, Matthias Kaehlcke wrote:
>> On Thu, Jun 04, 2020 at 04:44:42PM +0530, Pradeep P V K wrote:
>>> Interconnect bandwidth scaling support is now added as a
>>> part of OPP [1]. So, make sure interconnect driver is ready
>>> before handling interconnect scaling.
>>>
>>> This change is based on
>>> [1] [Patch v8] Introduce OPP bandwidth bindings
>>> (https://lkml.org/lkml/2020/5/12/493)
>>>
>>> [2] [Patch v3] mmc: sdhci-msm: Fix error handling
>>> for dev_pm_opp_of_add_table()
>>> (https://lkml.org/lkml/2020/5/5/491)
>>>
>>> Signed-off-by: Pradeep P V K <[email protected]>
>>> ---
>>> drivers/mmc/host/sdhci-msm.c | 13 +++++++++++++
>>> 1 file changed, 13 insertions(+)
>>>
>>> diff --git a/drivers/mmc/host/sdhci-msm.c
>>> b/drivers/mmc/host/sdhci-msm.c
>>> index b277dd7..a13ff1b 100644
>>> --- a/drivers/mmc/host/sdhci-msm.c
>>> +++ b/drivers/mmc/host/sdhci-msm.c
>>> @@ -14,6 +14,7 @@
>>> #include <linux/slab.h>
>>> #include <linux/iopoll.h>
>>> #include <linux/regulator/consumer.h>
>>> +#include <linux/interconnect.h>
>>>
>>> #include "sdhci-pltfm.h"
>>> #include "cqhci.h"
>>> @@ -2070,6 +2071,18 @@ static int sdhci_msm_probe(struct
>>> platform_device *pdev)
>>> }
>>> msm_host->bulk_clks[0].clk = clk;
>>>
>>> + /* Make sure that ICC driver is ready for interconnect bandwdith
>>> + * scaling before registering the device for OPP.
>>> + */
>>> + ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
>>> + if (ret) {
>>> + if (ret == -EPROBE_DEFER)
>>> + dev_info(&pdev->dev, "defer icc path: %d\n", ret);
>>
>> I already commented on this on v1:
>>
>> This log seems to add little more than noise, or are there
>> particular reasons
>> why it is useful in this driver? Most drivers just return silently
>> in case of
>> deferred probing.
>>
>> If you think the log is really needed please explain why.
>
Sorry. i forget to remove this print on V2. i will address this in my
next patch set.

> Both the err logs seem redundant.
> EPROBE_DEFERS are rather readily
> noticeable through the return val.
> dev_.._find_icc_paths already prints
> err messages when we fail to get icc
> paths.

True. i will remove this too in my next patch set.