[PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Alok Chauhan]

Get the interconnect paths for I2C based Serial Engine device
and vote accordingly based on maximum supported I2C frequency.

Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
---
 drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index db075bc..e8fe63a 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -14,6 +14,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/qcom-geni-se.h>
 #include <linux/spinlock.h>
+#include <linux/interconnect.h>
 
 #define SE_I2C_TX_TRANS_LEN		0x26c
 #define SE_I2C_RX_TRANS_LEN		0x270
@@ -508,6 +509,15 @@ static int geni_i2c_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* Set the bus quota to a reasonable value */
+	gi2c->se.avg_bw = Bps_to_icc(1000);
+	gi2c->se.peak_bw = Bps_to_icc(76800000);
+	ret = geni_interconnect_init(&gi2c->se);
+	if (ret) {
+		dev_err(&pdev->dev, "interconnect_init failed %d\n", ret);
+		return ret;
+	}
+
 	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
 							&gi2c->clk_freq_out);
 	if (ret) {
@@ -611,6 +621,8 @@ static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
 		gi2c->suspended = 1;
 	}
 
+	geni_icc_update_bw(&gi2c->se, false);
+
 	return 0;
 }
 
@@ -619,6 +631,7 @@ static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
 	int ret;
 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
 
+	geni_icc_update_bw(&gi2c->se, true);
 	ret = geni_se_resources_on(&gi2c->se);
 	if (ret)
 		return ret;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Alok Chauhan]

Get the interconnect paths for I2C based Serial Engine device
and vote accordingly based on maximum supported I2C frequency.

Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
---
 drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index db075bc..e8fe63a 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -14,6 +14,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/qcom-geni-se.h>
 #include <linux/spinlock.h>
+#include <linux/interconnect.h>
 
 #define SE_I2C_TX_TRANS_LEN		0x26c
 #define SE_I2C_RX_TRANS_LEN		0x270
@@ -508,6 +509,15 @@ static int geni_i2c_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* Set the bus quota to a reasonable value */
+	gi2c->se.avg_bw = Bps_to_icc(1000);
+	gi2c->se.peak_bw = Bps_to_icc(76800000);
+	ret = geni_interconnect_init(&gi2c->se);
+	if (ret) {
+		dev_err(&pdev->dev, "interconnect_init failed %d\n", ret);
+		return ret;
+	}
+
 	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
 							&gi2c->clk_freq_out);
 	if (ret) {
@@ -611,6 +621,8 @@ static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
 		gi2c->suspended = 1;
 	}
 
+	geni_icc_update_bw(&gi2c->se, false);
+
 	return 0;
 }
 
@@ -619,6 +631,7 @@ static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
 	int ret;
 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
 
+	geni_icc_update_bw(&gi2c->se, true);
 	ret = geni_se_resources_on(&gi2c->se);
 	if (ret)
 		return ret;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[alokc]

Please don't review this patch. I've resend patches after adding all the 
mailing list.
Sorry for inconvenience. Please review patches with spi/i2c/uart/kernel 
mailing list added.

On 2019-01-21 16:51, Alok Chauhan wrote:
> Get the interconnect paths for I2C based Serial Engine device
> and vote accordingly based on maximum supported I2C frequency.
> 
> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
> ---
>  drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c
> b/drivers/i2c/busses/i2c-qcom-geni.c
> index db075bc..e8fe63a 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -14,6 +14,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/qcom-geni-se.h>
>  #include <linux/spinlock.h>
> +#include <linux/interconnect.h>
> 
>  #define SE_I2C_TX_TRANS_LEN		0x26c
>  #define SE_I2C_RX_TRANS_LEN		0x270
> @@ -508,6 +509,15 @@ static int geni_i2c_probe(struct platform_device 
> *pdev)
>  		return ret;
>  	}
> 
> +	/* Set the bus quota to a reasonable value */
> +	gi2c->se.avg_bw = Bps_to_icc(1000);
> +	gi2c->se.peak_bw = Bps_to_icc(76800000);
> +	ret = geni_interconnect_init(&gi2c->se);
> +	if (ret) {
> +		dev_err(&pdev->dev, "interconnect_init failed %d\n", ret);
> +		return ret;
> +	}
> +
>  	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
>  							&gi2c->clk_freq_out);
>  	if (ret) {
> @@ -611,6 +621,8 @@ static int __maybe_unused
> geni_i2c_runtime_suspend(struct device *dev)
>  		gi2c->suspended = 1;
>  	}
> 
> +	geni_icc_update_bw(&gi2c->se, false);
> +
>  	return 0;
>  }
> 
> @@ -619,6 +631,7 @@ static int __maybe_unused
> geni_i2c_runtime_resume(struct device *dev)
>  	int ret;
>  	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
> 
> +	geni_icc_update_bw(&gi2c->se, true);
>  	ret = geni_se_resources_on(&gi2c->se);
>  	if (ret)
>  		return ret;

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

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Wolfram Sang]

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On Tue, Jan 22, 2019 at 12:03:33PM +0530, Alok Chauhan wrote:
> Get the interconnect paths for I2C based Serial Engine device
> and vote accordingly based on maximum supported I2C frequency.
> 
> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>

Acked-by: Wolfram Sang <wsa@the-dreams.de>


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Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Peter Rosin]

On 2019-01-22 07:33, Alok Chauhan wrote:
> Get the interconnect paths for I2C based Serial Engine device
> and vote accordingly based on maximum supported I2C frequency.
> 
> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
> ---
>  drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index db075bc..e8fe63a 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -14,6 +14,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/qcom-geni-se.h>
>  #include <linux/spinlock.h>
> +#include <linux/interconnect.h>

Please keep the includes sorted. Probably applies for the other patches
in the series as well?

Cheers,
Peter

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[alokc]

On 2019-01-22 14:43, Peter Rosin wrote:
> On 2019-01-22 07:33, Alok Chauhan wrote:
>> Get the interconnect paths for I2C based Serial Engine device
>> and vote accordingly based on maximum supported I2C frequency.
>> 
>> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
>> ---
>>  drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
>>  1 file changed, 13 insertions(+)
>> 
>> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c 
>> b/drivers/i2c/busses/i2c-qcom-geni.c
>> index db075bc..e8fe63a 100644
>> --- a/drivers/i2c/busses/i2c-qcom-geni.c
>> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
>> @@ -14,6 +14,7 @@
>>  #include <linux/pm_runtime.h>
>>  #include <linux/qcom-geni-se.h>
>>  #include <linux/spinlock.h>
>> +#include <linux/interconnect.h>
> 
> Please keep the includes sorted. Probably applies for the other patches
> in the series as well?
> 
> Cheers,
> Peter

Sure, will do. Thanks for your comment.

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

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Evan Green]

On Mon, Jan 21, 2019 at 10:34 PM Alok Chauhan <alokc@codeaurora.org> wrote:
>
> Get the interconnect paths for I2C based Serial Engine device
> and vote accordingly based on maximum supported I2C frequency.
>
> Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
> ---
>  drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
>
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index db075bc..e8fe63a 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -14,6 +14,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/qcom-geni-se.h>
>  #include <linux/spinlock.h>
> +#include <linux/interconnect.h>
>
>  #define SE_I2C_TX_TRANS_LEN            0x26c
>  #define SE_I2C_RX_TRANS_LEN            0x270
> @@ -508,6 +509,15 @@ static int geni_i2c_probe(struct platform_device *pdev)
>                 return ret;
>         }
>
> +       /* Set the bus quota to a reasonable value */
> +       gi2c->se.avg_bw = Bps_to_icc(1000);
> +       gi2c->se.peak_bw = Bps_to_icc(76800000);

Can you compute a real bandwidth based on the i2c bus speed, rather
than some max vote?

[PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Akash Asthana]

Get the interconnect paths for I2C based Serial Engine device
and vote according to the bus speed of the driver.

Signed-off-by: Akash Asthana <akashast-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
---
 drivers/i2c/busses/i2c-qcom-geni.c | 84 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 80 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index 17abf60c..5de10a1 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -163,6 +163,44 @@ static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
 	writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
 }
 
+static int geni_i2c_icc_get(struct geni_se *se)
+{
+	if (!se)
+		return -EINVAL;
+
+	se->icc_path[GENI_TO_CORE] = of_icc_get(se->dev, "qup-core");
+	if (IS_ERR(se->icc_path[GENI_TO_CORE]))
+		return PTR_ERR(se->icc_path[GENI_TO_CORE]);
+
+	se->icc_path[CPU_TO_GENI] = of_icc_get(se->dev, "qup-config");
+	if (IS_ERR(se->icc_path[CPU_TO_GENI])) {
+		icc_put(se->icc_path[GENI_TO_CORE]);
+		se->icc_path[GENI_TO_CORE] = NULL;
+		return PTR_ERR(se->icc_path[CPU_TO_GENI]);
+	}
+
+	se->icc_path[GENI_TO_DDR] = of_icc_get(se->dev, "qup-memory");
+	if (IS_ERR(se->icc_path[GENI_TO_DDR])) {
+		icc_put(se->icc_path[GENI_TO_CORE]);
+		se->icc_path[GENI_TO_CORE] = NULL;
+		icc_put(se->icc_path[CPU_TO_GENI]);
+		se->icc_path[CPU_TO_GENI] = NULL;
+		return PTR_ERR(se->icc_path[GENI_TO_DDR]);
+	}
+
+	return 0;
+}
+
+void geni_i2c_icc_put(struct geni_se *se)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(se->icc_path); i++) {
+		icc_put(se->icc_path[i]);
+		se->icc_path[i] = NULL;
+	}
+}
+
 static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
 {
 	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
@@ -563,17 +601,34 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	gi2c->adap.dev.of_node = pdev->dev.of_node;
 	strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
 
+	ret = geni_i2c_icc_get(&gi2c->se);
+	if (ret)
+		return ret;
+	/* Set the bus quota to a reasonable value */
+	gi2c->se.avg_bw_core = Bps_to_icc(1000);
+	gi2c->se.peak_bw_core = Bps_to_icc(CORE_2X_100_MHZ);
+	gi2c->se.avg_bw_cpu = Bps_to_icc(1000);
+	gi2c->se.peak_bw_cpu = Bps_to_icc(1000);
+	gi2c->se.avg_bw_ddr = Bps_to_icc(gi2c->clk_freq_out);
+	gi2c->se.peak_bw_ddr = Bps_to_icc(2 * gi2c->clk_freq_out);
+
+	/* Vote for core clocks and CPU for register access */
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], gi2c->se.avg_bw_core,
+				gi2c->se.peak_bw_core);
+	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], gi2c->se.avg_bw_cpu,
+				gi2c->se.peak_bw_cpu);
 	ret = geni_se_resources_on(&gi2c->se);
 	if (ret) {
 		dev_err(&pdev->dev, "Error turning on resources %d\n", ret);
-		return ret;
+		goto geni_i2c_put_icc;
 	}
 	proto = geni_se_read_proto(&gi2c->se);
 	tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
 	if (proto != GENI_SE_I2C) {
 		dev_err(&pdev->dev, "Invalid proto %d\n", proto);
 		geni_se_resources_off(&gi2c->se);
-		return -ENXIO;
+		ret = -ENXIO;
+		goto geni_i2c_put_icc;
 	}
 	gi2c->tx_wm = tx_depth - 1;
 	geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth);
@@ -582,8 +637,11 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	ret = geni_se_resources_off(&gi2c->se);
 	if (ret) {
 		dev_err(&pdev->dev, "Error turning off resources %d\n", ret);
-		return ret;
+		goto geni_i2c_put_icc;
 	}
+	/* Remove vote from core clocks and CPU */
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], 0, 0);
+	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], 0, 0);
 
 	dev_dbg(&pdev->dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
 
@@ -597,12 +655,16 @@ static int geni_i2c_probe(struct platform_device *pdev)
 	if (ret) {
 		dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
 		pm_runtime_disable(gi2c->se.dev);
-		return ret;
+		goto geni_i2c_put_icc;
 	}
 
 	dev_dbg(&pdev->dev, "Geni-I2C adaptor successfully added\n");
 
 	return 0;
+
+geni_i2c_put_icc:
+	geni_i2c_icc_put(&gi2c->se);
+	return ret;
 }
 
 static int geni_i2c_remove(struct platform_device *pdev)
@@ -611,6 +673,7 @@ static int geni_i2c_remove(struct platform_device *pdev)
 
 	i2c_del_adapter(&gi2c->adap);
 	pm_runtime_disable(gi2c->se.dev);
+	geni_i2c_icc_put(&gi2c->se);
 	return 0;
 }
 
@@ -629,6 +692,11 @@ static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
 		gi2c->suspended = 1;
 	}
 
+	/* Remove BW votes */
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], 0, 0);
+	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], 0, 0);
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_DDR], 0, 0);
+
 	return 0;
 }
 
@@ -637,6 +705,14 @@ static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
 	int ret;
 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
 
+	/* Vote on Core, DDR and CPU path respectively */
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], gi2c->se.avg_bw_core,
+		gi2c->se.peak_bw_core);
+	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], gi2c->se.avg_bw_cpu,
+		gi2c->se.peak_bw_cpu);
+	icc_set_bw(gi2c->se.icc_path[GENI_TO_DDR], gi2c->se.avg_bw_ddr,
+		gi2c->se.peak_bw_ddr);
+
 	ret = geni_se_resources_on(&gi2c->se);
 	if (ret)
 		return ret;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,\na Linux Foundation Collaborative Project

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Matthias Kaehlcke]

On Mon, Feb 17, 2020 at 07:00:02PM +0530, Akash Asthana wrote:
> Get the interconnect paths for I2C based Serial Engine device
> and vote according to the bus speed of the driver.
> 
> Signed-off-by: Akash Asthana <akashast-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
> ---
>  drivers/i2c/busses/i2c-qcom-geni.c | 84 ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 80 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index 17abf60c..5de10a1 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -163,6 +163,44 @@ static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
>  	writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
>  }
>  
> +static int geni_i2c_icc_get(struct geni_se *se)
> +{
> +	if (!se)
> +		return -EINVAL;

check is not needed

> +
> +	se->icc_path[GENI_TO_CORE] = of_icc_get(se->dev, "qup-core");
> +	if (IS_ERR(se->icc_path[GENI_TO_CORE]))
> +		return PTR_ERR(se->icc_path[GENI_TO_CORE]);
> +
> +	se->icc_path[CPU_TO_GENI] = of_icc_get(se->dev, "qup-config");
> +	if (IS_ERR(se->icc_path[CPU_TO_GENI])) {
> +		icc_put(se->icc_path[GENI_TO_CORE]);
> +		se->icc_path[GENI_TO_CORE] = NULL;

echoing Bjorn's comments on 'tty: serial: qcom_geni_serial: Add
interconnect support', resetting is not needed since _probe() will
fail.

> +		return PTR_ERR(se->icc_path[CPU_TO_GENI]);
> +	}
> +
> +	se->icc_path[GENI_TO_DDR] = of_icc_get(se->dev, "qup-memory");
> +	if (IS_ERR(se->icc_path[GENI_TO_DDR])) {
> +		icc_put(se->icc_path[GENI_TO_CORE]);
> +		se->icc_path[GENI_TO_CORE] = NULL;

ditto

> +		icc_put(se->icc_path[CPU_TO_GENI]);
> +		se->icc_path[CPU_TO_GENI] = NULL;

ditto

> +		return PTR_ERR(se->icc_path[GENI_TO_DDR]);
> +	}
> +
> +	return 0;
> +}
> +
> +void geni_i2c_icc_put(struct geni_se *se)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(se->icc_path); i++) {
> +		icc_put(se->icc_path[i]);
> +		se->icc_path[i] = NULL;

not needed

> +	}
> +}
> +
>  static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
>  {
>  	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
> @@ -563,17 +601,34 @@ static int geni_i2c_probe(struct platform_device *pdev)
>  	gi2c->adap.dev.of_node = pdev->dev.of_node;
>  	strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
>  
> +	ret = geni_i2c_icc_get(&gi2c->se);
> +	if (ret)
> +		return ret;
> +	/* Set the bus quota to a reasonable value */
> +	gi2c->se.avg_bw_core = Bps_to_icc(1000);
> +	gi2c->se.peak_bw_core = Bps_to_icc(CORE_2X_100_MHZ);
> +	gi2c->se.avg_bw_cpu = Bps_to_icc(1000);
> +	gi2c->se.peak_bw_cpu = Bps_to_icc(1000);
> +	gi2c->se.avg_bw_ddr = Bps_to_icc(gi2c->clk_freq_out);
> +	gi2c->se.peak_bw_ddr = Bps_to_icc(2 * gi2c->clk_freq_out);
> +
> +	/* Vote for core clocks and CPU for register access */
> +	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], gi2c->se.avg_bw_core,
> +				gi2c->se.peak_bw_core);
> +	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], gi2c->se.avg_bw_cpu,
> +				gi2c->se.peak_bw_cpu);

error handling needed?

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Akash Asthana]

Hi Matthias,

On 2/19/2020 4:17 AM, Matthias Kaehlcke wrote:
> On Mon, Feb 17, 2020 at 07:00:02PM +0530, Akash Asthana wrote:
>> Get the interconnect paths for I2C based Serial Engine device
>> and vote according to the bus speed of the driver.
>>
>> Signed-off-by: Akash Asthana <akashast@codeaurora.org>
>> ---
>>   drivers/i2c/busses/i2c-qcom-geni.c | 84 ++++++++++++++++++++++++++++++++++++--
>>   1 file changed, 80 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
>> index 17abf60c..5de10a1 100644
>> --- a/drivers/i2c/busses/i2c-qcom-geni.c
>> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
>> @@ -163,6 +163,44 @@ static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
>>   	writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
>>   }
>>   
>> +static int geni_i2c_icc_get(struct geni_se *se)
>> +{
>> +	if (!se)
>> +		return -EINVAL;
> check is not needed
ok, will remove.
>
>> +
>> +	se->icc_path[GENI_TO_CORE] = of_icc_get(se->dev, "qup-core");
>> +	if (IS_ERR(se->icc_path[GENI_TO_CORE]))
>> +		return PTR_ERR(se->icc_path[GENI_TO_CORE]);
>> +
>> +	se->icc_path[CPU_TO_GENI] = of_icc_get(se->dev, "qup-config");
>> +	if (IS_ERR(se->icc_path[CPU_TO_GENI])) {
>> +		icc_put(se->icc_path[GENI_TO_CORE]);
>> +		se->icc_path[GENI_TO_CORE] = NULL;
> echoing Bjorn's comments on 'tty: serial: qcom_geni_serial: Add
> interconnect support', resetting is not needed since _probe() will
> fail.
ok, will remove
>> +		return PTR_ERR(se->icc_path[CPU_TO_GENI]);
>> +	}
>> +
>> +	se->icc_path[GENI_TO_DDR] = of_icc_get(se->dev, "qup-memory");
>> +	if (IS_ERR(se->icc_path[GENI_TO_DDR])) {
>> +		icc_put(se->icc_path[GENI_TO_CORE]);
>> +		se->icc_path[GENI_TO_CORE] = NULL;
> ditto
ok
>> +		icc_put(se->icc_path[CPU_TO_GENI]);
>> +		se->icc_path[CPU_TO_GENI] = NULL;
> ditto
ok
>> +		return PTR_ERR(se->icc_path[GENI_TO_DDR]);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void geni_i2c_icc_put(struct geni_se *se)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < ARRAY_SIZE(se->icc_path); i++) {
>> +		icc_put(se->icc_path[i]);
>> +		se->icc_path[i] = NULL;
> not needed
ok, will remove
>> +	}
>> +}
>> +
>>   static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
>>   {
>>   	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
>> @@ -563,17 +601,34 @@ static int geni_i2c_probe(struct platform_device *pdev)
>>   	gi2c->adap.dev.of_node = pdev->dev.of_node;
>>   	strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
>>   
>> +	ret = geni_i2c_icc_get(&gi2c->se);
>> +	if (ret)
>> +		return ret;
>> +	/* Set the bus quota to a reasonable value */
>> +	gi2c->se.avg_bw_core = Bps_to_icc(1000);
>> +	gi2c->se.peak_bw_core = Bps_to_icc(CORE_2X_100_MHZ);
>> +	gi2c->se.avg_bw_cpu = Bps_to_icc(1000);
>> +	gi2c->se.peak_bw_cpu = Bps_to_icc(1000);
>> +	gi2c->se.avg_bw_ddr = Bps_to_icc(gi2c->clk_freq_out);
>> +	gi2c->se.peak_bw_ddr = Bps_to_icc(2 * gi2c->clk_freq_out);
>> +
>> +	/* Vote for core clocks and CPU for register access */
>> +	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], gi2c->se.avg_bw_core,
>> +				gi2c->se.peak_bw_core);
>> +	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], gi2c->se.avg_bw_cpu,
>> +				gi2c->se.peak_bw_cpu);
> error handling needed?

I will add error handling for GENI_TO_CORE path in all the drivers. Will 
it be okay if we don't handle errors for CPU_TO_GENI and GENI_TO_DDR path

as CPU and DDR will be running at much higher frequency?

Regards,

Akash

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

Re: [PATCH 3/6] i2c: i2c-qcom-geni: Add interconnect support

[Matthias Kaehlcke]

Hi Akash,

On Wed, Feb 19, 2020 at 07:17:44PM +0530, Akash Asthana wrote:
> Hi Matthias,
> 
> On 2/19/2020 4:17 AM, Matthias Kaehlcke wrote:
> > On Mon, Feb 17, 2020 at 07:00:02PM +0530, Akash Asthana wrote:
> > > Get the interconnect paths for I2C based Serial Engine device
> > > and vote according to the bus speed of the driver.
> > > 
> > > Signed-off-by: Akash Asthana <akashast@codeaurora.org>
> > > ---
> > >   drivers/i2c/busses/i2c-qcom-geni.c | 84 ++++++++++++++++++++++++++++++++++++--
> > >   1 file changed, 80 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> > > index 17abf60c..5de10a1 100644
> > > --- a/drivers/i2c/busses/i2c-qcom-geni.c
> > > +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> > >
> > >   static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
> > >   {
> > >   	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
> > > @@ -563,17 +601,34 @@ static int geni_i2c_probe(struct platform_device *pdev)
> > >   	gi2c->adap.dev.of_node = pdev->dev.of_node;
> > >   	strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
> > > +	ret = geni_i2c_icc_get(&gi2c->se);
> > > +	if (ret)
> > > +		return ret;
> > > +	/* Set the bus quota to a reasonable value */
> > > +	gi2c->se.avg_bw_core = Bps_to_icc(1000);
> > > +	gi2c->se.peak_bw_core = Bps_to_icc(CORE_2X_100_MHZ);
> > > +	gi2c->se.avg_bw_cpu = Bps_to_icc(1000);
> > > +	gi2c->se.peak_bw_cpu = Bps_to_icc(1000);
> > > +	gi2c->se.avg_bw_ddr = Bps_to_icc(gi2c->clk_freq_out);
> > > +	gi2c->se.peak_bw_ddr = Bps_to_icc(2 * gi2c->clk_freq_out);
> > > +
> > > +	/* Vote for core clocks and CPU for register access */
> > > +	icc_set_bw(gi2c->se.icc_path[GENI_TO_CORE], gi2c->se.avg_bw_core,
> > > +				gi2c->se.peak_bw_core);
> > > +	icc_set_bw(gi2c->se.icc_path[CPU_TO_GENI], gi2c->se.avg_bw_cpu,
> > > +				gi2c->se.peak_bw_cpu);
> > error handling needed?
> 
> I will add error handling for GENI_TO_CORE path in all the drivers. Will it
> be okay if we don't handle errors for CPU_TO_GENI and GENI_TO_DDR path
> 
> as CPU and DDR will be running at much higher frequency?

It may still work, but you might never know that there was a problem. I
would be inclined to check the return value of all invocations of icc_set_bw()
- including runtime suspend/resume - and log a message if a problem is
detected. For runtime suspend/resume it would probably be wise to use
dev_err_ratelimited(), to avoid spamming the system log too much in case of
a persistent problem.

If others think that error checking all icc_set_bw() calls is overkill
please speak up :)

Thanks

Matthias