[PATCH V1 0/2] Add SDHC interconnect bandwidth scaling

[PATCH V1 0/2] Add SDHC interconnect bandwidth scaling

[Pradeep P V K]

Add interconnect bandwidths for SDHC driver using OPP framework that
is required by SDHC driver based on the clock frequency and bus width
of the card. Otherwise, the system clocks may run at minimum clock
speed and thus affecting the performance.

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

[2] [Patch v3 09/17] mmc: sdhci-msm: Fix error handling
for dev_pm_opp_of_add_table()
(https://lkml.org/lkml/2020/5/5/491)

[3] [RFC v6 2/2] dt-bindings: mmc: sdhci-msm: Add interconnect BW
scaling strings
(https://lkml.org/lkml/2020/3/23/409)

as there were no extra changes made on [3], retaining the Acked-by and
Reviewed-by sign-off from [3].

Pradeep P V K (2):
  mmc: sdhci-msm: Add interconnect bandwidth scaling support
  dt-bindings: mmc: sdhci-msm: Add interconnect BW scaling strings

 Documentation/devicetree/bindings/mmc/sdhci-msm.txt | 18 ++++++++++++++++++
 drivers/mmc/host/sdhci-msm.c                        | 16 ++++++++++++++++
 2 files changed, 34 insertions(+)

-- 
1.9.1

[PATCH V1 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[Pradeep P V K]

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 <ppvk@codeaurora.org>
---
 drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index b277dd7..bf95484 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"
@@ -1999,6 +2000,7 @@ static int sdhci_msm_probe(struct platform_device *pdev)
 	struct sdhci_pltfm_host *pltfm_host;
 	struct sdhci_msm_host *msm_host;
 	struct clk *clk;
+	struct icc_path *sdhc_path;
 	int ret;
 	u16 host_version, core_minor;
 	u32 core_version, config;
@@ -2070,6 +2072,20 @@ 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.
+	 */
+	sdhc_path = of_icc_get(&pdev->dev, NULL);
+	ret = PTR_ERR_OR_ZERO(sdhc_path);
+	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;
+	}
+	icc_put(sdhc_path);
+
 	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

[PATCH V1 2/2] dt-bindings: mmc: sdhci-msm: Add interconnect BW scaling strings

[Pradeep P V K]

Add interconnect bandwidth scaling supported strings for qcom-sdhci
controller.

Signed-off-by: Pradeep P V K <ppvk@codeaurora.org>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---
 Documentation/devicetree/bindings/mmc/sdhci-msm.txt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
index b8e1d2b..3b602fd 100644
--- a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
+++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt
@@ -54,6 +54,21 @@ Required properties:
 - qcom,dll-config: Chipset and Platform specific value. Use this field to
 	specify the DLL_CONFIG register value as per Hardware Programming Guide.
 
+Optional Properties:
+* Following bus parameters are required for interconnect bandwidth scaling:
+- interconnects: Pairs of phandles and interconnect provider specifier
+		 to denote the edge source and destination ports of
+		 the interconnect path.
+
+- interconnect-names: For sdhc, we have two main paths.
+		1. Data path : sdhc to ddr
+		2. Config path : cpu to sdhc
+		For Data interconnect path the name supposed to be
+		is "sdhc-ddr" and for config interconnect path it is
+		"cpu-sdhc".
+		Please refer to Documentation/devicetree/bindings/
+		interconnect/ for more details.
+
 Example:
 
 	sdhc_1: sdhci@f9824900 {
@@ -71,6 +86,9 @@ Example:
 
 		clocks = <&gcc GCC_SDCC1_APPS_CLK>, <&gcc GCC_SDCC1_AHB_CLK>;
 		clock-names = "core", "iface";
+		interconnects = <&qnoc MASTER_SDCC_ID &qnoc SLAVE_DDR_ID>,
+				<&qnoc MASTER_CPU_ID &qnoc SLAVE_SDCC_ID>;
+		interconnect-names = "sdhc-ddr","cpu-sdhc";
 
 		qcom,dll-config = <0x000f642c>;
 		qcom,ddr-config = <0x80040868>;
-- 
1.9.1

Re: [PATCH V1 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[Sibi Sankar]

Hey Pradeep,
Thanks for the patch.

On 2020-06-03 14:39, 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 <ppvk@codeaurora.org>
> ---
>  drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c 
> b/drivers/mmc/host/sdhci-msm.c
> index b277dd7..bf95484 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"
> @@ -1999,6 +2000,7 @@ static int sdhci_msm_probe(struct platform_device 
> *pdev)
>  	struct sdhci_pltfm_host *pltfm_host;
>  	struct sdhci_msm_host *msm_host;
>  	struct clk *clk;
> +	struct icc_path *sdhc_path;
>  	int ret;
>  	u16 host_version, core_minor;
>  	u32 core_version, config;
> @@ -2070,6 +2072,20 @@ 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.
> +	 */
> +	sdhc_path = of_icc_get(&pdev->dev, NULL);
> +	ret = PTR_ERR_OR_ZERO(sdhc_path);
> +	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;
> +	}
> +	icc_put(sdhc_path);

ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);

since there are multiple paths
described in the bindings you
should use ^^ instead and you
can drop temporary path as well.

> +
>  	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);

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

Re: [PATCH V1 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[Matthias Kaehlcke]

Hi Pradeep,

On Wed, Jun 03, 2020 at 02:39:35PM +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 <ppvk@codeaurora.org>
> ---
>  drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index b277dd7..bf95484 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"
> @@ -1999,6 +2000,7 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>  	struct sdhci_pltfm_host *pltfm_host;
>  	struct sdhci_msm_host *msm_host;
>  	struct clk *clk;
> +	struct icc_path *sdhc_path;

nit: The 'sdhc_' prefix doesn't provide any useful information, change it
to 'icc_path', which makes evident what it is?

>  	int ret;
>  	u16 host_version, core_minor;
>  	u32 core_version, config;
> @@ -2070,6 +2072,20 @@ 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.
> +	 */
> +	sdhc_path = of_icc_get(&pdev->dev, NULL);
> +	ret = PTR_ERR_OR_ZERO(sdhc_path);
> +	if (ret) {

nit: IMO it would be clearer to do this instead of using PTR_ERR_OR_ZERO()
(as for the OPP table below):

	if (IS_ERR(sdhc_path)) {
		ret = PTR_ERR(sdhc_path);

> +		if (ret == -EPROBE_DEFER)
> +			dev_info(&pdev->dev, "defer icc path: %d\n", ret);

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.

> +		else
> +			dev_err(&pdev->dev, "failed to get icc path:%d\n", ret);
> +		goto bus_clk_disable;
> +	}
> +	icc_put(sdhc_path);
> +
>  	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
> 

Re: [PATCH V1 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[ppvk]

Hi Sibi,

Thanks for the review!!

On 2020-06-03 17:22, Sibi Sankar wrote:
> Hey Pradeep,
> Thanks for the patch.
> 
> On 2020-06-03 14:39, 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 <ppvk@codeaurora.org>
>> ---
>>  drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++++
>>  1 file changed, 16 insertions(+)
>> 
>> diff --git a/drivers/mmc/host/sdhci-msm.c 
>> b/drivers/mmc/host/sdhci-msm.c
>> index b277dd7..bf95484 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"
>> @@ -1999,6 +2000,7 @@ static int sdhci_msm_probe(struct 
>> platform_device *pdev)
>>  	struct sdhci_pltfm_host *pltfm_host;
>>  	struct sdhci_msm_host *msm_host;
>>  	struct clk *clk;
>> +	struct icc_path *sdhc_path;
>>  	int ret;
>>  	u16 host_version, core_minor;
>>  	u32 core_version, config;
>> @@ -2070,6 +2072,20 @@ 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.
>> +	 */
>> +	sdhc_path = of_icc_get(&pdev->dev, NULL);
>> +	ret = PTR_ERR_OR_ZERO(sdhc_path);
>> +	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;
>> +	}
>> +	icc_put(sdhc_path);
> 
> ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
> 
> since there are multiple paths
> described in the bindings you
> should use ^^ instead and you
> can drop temporary path as well.
> 
Ok. of_icc_get() used above is only to test if ICC driver is ready or 
not. I'm not
really using the multiple paths here. Anyhow i will use 
dev_pm_opp_of_find_icc_paths()
to get rid of some extra lines of code.

>> +
>>  	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);

Re: [PATCH V1 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[Sibi Sankar]

On 2020-06-04 16:43, ppvk@codeaurora.org wrote:
> Hi Sibi,
> 
> Thanks for the review!!
> 
> On 2020-06-03 17:22, Sibi Sankar wrote:
>> Hey Pradeep,
>> Thanks for the patch.
>> 
>> On 2020-06-03 14:39, 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 <ppvk@codeaurora.org>
>>> ---
>>>  drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++++
>>>  1 file changed, 16 insertions(+)
>>> 
>>> diff --git a/drivers/mmc/host/sdhci-msm.c 
>>> b/drivers/mmc/host/sdhci-msm.c
>>> index b277dd7..bf95484 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"
>>> @@ -1999,6 +2000,7 @@ static int sdhci_msm_probe(struct 
>>> platform_device *pdev)
>>>  	struct sdhci_pltfm_host *pltfm_host;
>>>  	struct sdhci_msm_host *msm_host;
>>>  	struct clk *clk;
>>> +	struct icc_path *sdhc_path;
>>>  	int ret;
>>>  	u16 host_version, core_minor;
>>>  	u32 core_version, config;
>>> @@ -2070,6 +2072,20 @@ 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.
>>> +	 */
>>> +	sdhc_path = of_icc_get(&pdev->dev, NULL);
>>> +	ret = PTR_ERR_OR_ZERO(sdhc_path);
>>> +	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;
>>> +	}
>>> +	icc_put(sdhc_path);
>> 
>> ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
>> 
>> since there are multiple paths
>> described in the bindings you
>> should use ^^ instead and you
>> can drop temporary path as well.
>> 
> Ok. of_icc_get() used above is only to test if ICC driver is ready or
> not. I'm not
> really using the multiple paths here. Anyhow i will use
> dev_pm_opp_of_find_icc_paths()
> to get rid of some extra lines of code.

Using dev_pm_opp_of_find_icc_paths
with NULL passed acts as a way of
validating all the paths specified
in the device and also validates if
the opp-table has bw related bindings
as well.

> 
>>> +
>>>  	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);

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