[PATCH v4 0/6] cpufreq: qcom-nvmem: support apq8064 cpufreq scaling

[PATCH v4 0/6] cpufreq: qcom-nvmem: support apq8064 cpufreq scaling

[Dmitry Baryshkov]

This is a split of APQ8064 cpufreq series, as requested by Viresh. This
series includes only opp and cpufreq parts, with the DT and soc parts
being split to a separate patchset.

Each core has independent power and frequency control. Additionally the
L2 cache is scaled to follow the CPU frequencies (failure to do so
results in strange semi-random crashes).

Core voltage is controlled through the SAW2 devices, one for each core.
The L2 has two regulators, vdd-mem and vdd-dig.

Dmitry Baryshkov (6):
  dt-bindings: opp: opp-v2-kryo-cpu: support Qualcomm Krait SoCs
  cpufreq: qcom-nvmem: create L2 cache device
  cpufreq: qcom-nvmem: also accept operating-points-v2-krait-cpu
  cpufreq: qcom-nvmem: drop pvs_ver for format a fuses
  cpufreq: qcom-nvmem: provide separate configuration data for apq8064
  cpufreq: qcom-nvmem: enable core voltage scaling for MSM8960

 .../bindings/opp/opp-v2-kryo-cpu.yaml         | 12 ++-
 drivers/cpufreq/qcom-cpufreq-nvmem.c          | 80 +++++++++++++++++--
 2 files changed, 81 insertions(+), 11 deletions(-)

-- 
2.39.2

[PATCH v4 1/6] dt-bindings: opp: opp-v2-kryo-cpu: support Qualcomm Krait SoCs

[Dmitry Baryshkov]

Exted the opp-v2-kryo-cpu.yaml to support defining OPP tables for the
previous generation of Qualcomm CPUs, 32-bit Krait-based platforms.

It makes no sense to use 'operating-points-v2-kryo-cpu' compatibility
node for the Krait cores. Add support for the Krait-specific
'operating-points-v2-krait-cpu' compatibility string and the relevant
opp-microvolt subclasses properties.

The listed opp-supported-hw values are applicable only to msm8996 /
msm8996pro platforms. Remove the enum as other platforms will use other
bit values. It makes little sense to list all possible values for all
the platforms here.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../devicetree/bindings/opp/opp-v2-kryo-cpu.yaml     | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml b/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
index bbbad31ae4ca..4e84d06d5ff9 100644
--- a/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
+++ b/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
@@ -26,7 +26,9 @@ description: |
 
 properties:
   compatible:
-    const: operating-points-v2-kryo-cpu
+    enum:
+      - operating-points-v2-krait-cpu
+      - operating-points-v2-kryo-cpu
 
   nvmem-cells:
     description: |
@@ -63,14 +65,16 @@ patternProperties:
           5:  MSM8996SG, speedbin 1
           6:  MSM8996SG, speedbin 2
           7-31:  unused
-        enum: [0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
-               0x9, 0xd, 0xe, 0xf,
-               0x10, 0x20, 0x30, 0x70]
+
+          Other platforms use bits directly corresponding to speedbin index.
 
       clock-latency-ns: true
 
       required-opps: true
 
+    patternProperties:
+      '^opp-microvolt-speed[0-9]+-pvs[0-9]+$': true
+
     required:
       - opp-hz
 
-- 
2.39.2

[PATCH v4 2/6] cpufreq: qcom-nvmem: create L2 cache device

[Dmitry Baryshkov]

Scaling the frequencies on some of Qualcomm Krait platforms (e.g.
APQ8064) also requires scaling of the L2 cache frequency. As the
l2-cache device node is places under /cpus/ path, it is not created by
default by the OF code. Create corresponding device here.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-nvmem.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index 84d7033e5efe..f4c196ba4432 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -22,6 +22,7 @@
 #include <linux/module.h>
 #include <linux/nvmem-consumer.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_opp.h>
@@ -377,6 +378,7 @@ static int __init qcom_cpufreq_init(void)
 {
 	struct device_node *np = of_find_node_by_path("/");
 	const struct of_device_id *match;
+	unsigned int cpu;
 	int ret;
 
 	if (!np)
@@ -387,6 +389,25 @@ static int __init qcom_cpufreq_init(void)
 	if (!match)
 		return -ENODEV;
 
+	for_each_possible_cpu(cpu) {
+		struct device *dev = get_cpu_device(cpu);
+		struct device_node *cache;
+		struct platform_device *pdev;
+
+		cache = of_find_next_cache_node(dev->of_node);
+		if (!cache)
+			continue;
+
+		if (of_device_is_compatible(cache, "qcom,krait-l2-cache")) {
+			pdev = of_platform_device_create(cache, NULL, NULL);
+			if (IS_ERR(pdev))
+				pr_err("%s: %pe, failed to create L2 cache node\n", __func__, pdev);
+			/* the error is not fatal */
+		}
+
+		of_node_put(cache);
+	}
+
 	ret = platform_driver_register(&qcom_cpufreq_driver);
 	if (unlikely(ret < 0))
 		return ret;
-- 
2.39.2

[PATCH v4 3/6] cpufreq: qcom-nvmem: also accept operating-points-v2-krait-cpu

[Dmitry Baryshkov]

the qcom-cpufreq-nvmem driver attempts to support both Qualcomm Kryo
(newer 64-bit ARMv8 cores) and Krait (older 32-bit ARMv7 cores). It
makes no sense to use 'operating-points-v2-kryo-cpu' compatibility node
for the Krait cores. Add support for 'operating-points-v2-krait-cpu'
compatibility string.

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-nvmem.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index f4c196ba4432..04329ef61150 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -238,7 +238,8 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
 	if (!np)
 		return -ENOENT;
 
-	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu");
+	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu") ||
+	      of_device_is_compatible(np, "operating-points-v2-krait-cpu");
 	if (!ret) {
 		of_node_put(np);
 		return -ENOENT;
-- 
2.39.2

[PATCH v4 4/6] cpufreq: qcom-nvmem: drop pvs_ver for format a fuses

[Dmitry Baryshkov]

The fuses used on msm8960 / apq8064 / ipq806x families of devices do not
have the pvs version. Drop this argument from parsing function.

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-nvmem.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index 04329ef61150..81c080b854fe 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -50,7 +50,7 @@ struct qcom_cpufreq_drv {
 static struct platform_device *cpufreq_dt_pdev, *cpufreq_pdev;
 
 static void get_krait_bin_format_a(struct device *cpu_dev,
-					  int *speed, int *pvs, int *pvs_ver,
+					  int *speed, int *pvs,
 					  u8 *buf)
 {
 	u32 pte_efuse;
@@ -181,8 +181,7 @@ static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
 
 	switch (len) {
 	case 4:
-		get_krait_bin_format_a(cpu_dev, &speed, &pvs, &pvs_ver,
-				       speedbin);
+		get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
 		break;
 	case 8:
 		get_krait_bin_format_b(cpu_dev, &speed, &pvs, &pvs_ver,
-- 
2.39.2

[PATCH v4 5/6] cpufreq: qcom-nvmem: provide separate configuration data for apq8064

[Dmitry Baryshkov]

APQ8064 can scale core voltage according to the frequency needs. Rather
than reusing the A/B format multiplexer, use a simple fuse parsing
function and configure required regulator.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-nvmem.c | 49 ++++++++++++++++++++++++++--
 1 file changed, 47 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index 81c080b854fe..35e2610c9526 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -26,6 +26,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_opp.h>
+#include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/soc/qcom/smem.h>
 
@@ -39,6 +40,7 @@ struct qcom_cpufreq_match_data {
 			   char **pvs_name,
 			   struct qcom_cpufreq_drv *drv);
 	const char **genpd_names;
+	const char * const *regulator_names;
 };
 
 struct qcom_cpufreq_drv {
@@ -203,6 +205,34 @@ static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
 	return ret;
 }
 
+static int qcom_cpufreq_apq8064_name_version(struct device *cpu_dev,
+					     struct nvmem_cell *speedbin_nvmem,
+					     char **pvs_name,
+					     struct qcom_cpufreq_drv *drv)
+{
+	int speed = 0, pvs = 0;
+	u8 *speedbin;
+	size_t len;
+	int ret = 0;
+
+	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
+	if (IS_ERR(speedbin))
+		return PTR_ERR(speedbin);
+
+	if (len != 4)
+		return -EINVAL;
+
+	get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
+
+	snprintf(*pvs_name, sizeof("speedXX-pvsXX"), "speed%d-pvs%d",
+		 speed, pvs);
+
+	drv->versions = (1 << speed);
+
+	kfree(speedbin);
+	return ret;
+}
+
 static const struct qcom_cpufreq_match_data match_data_kryo = {
 	.get_version = qcom_cpufreq_kryo_name_version,
 };
@@ -217,6 +247,16 @@ static const struct qcom_cpufreq_match_data match_data_qcs404 = {
 	.genpd_names = qcs404_genpd_names,
 };
 
+static const char * apq8064_regulator_names[] = {
+	"vdd-core",
+	NULL
+};
+
+static const struct qcom_cpufreq_match_data match_data_apq8064 = {
+	.get_version = qcom_cpufreq_apq8064_name_version,
+	.regulator_names = apq8064_regulator_names,
+};
+
 static int qcom_cpufreq_probe(struct platform_device *pdev)
 {
 	struct qcom_cpufreq_drv *drv;
@@ -304,7 +344,12 @@ static int qcom_cpufreq_probe(struct platform_device *pdev)
 			config.virt_devs = NULL;
 		}
 
-		if (config.supported_hw || config.genpd_names) {
+		if (drv->data->regulator_names)
+			config.regulator_names = drv->data->regulator_names;
+
+		if (config.supported_hw ||
+		    config.genpd_names ||
+		    config.regulator_names) {
 			drv->opp_tokens[cpu] = dev_pm_opp_set_config(cpu_dev, &config);
 			if (drv->opp_tokens[cpu] < 0) {
 				ret = drv->opp_tokens[cpu];
@@ -361,7 +406,7 @@ static const struct of_device_id qcom_cpufreq_match_list[] __initconst = {
 	{ .compatible = "qcom,msm8996", .data = &match_data_kryo },
 	{ .compatible = "qcom,qcs404", .data = &match_data_qcs404 },
 	{ .compatible = "qcom,ipq8064", .data = &match_data_krait },
-	{ .compatible = "qcom,apq8064", .data = &match_data_krait },
+	{ .compatible = "qcom,apq8064", .data = &match_data_apq8064 },
 	{ .compatible = "qcom,msm8974", .data = &match_data_krait },
 	{ .compatible = "qcom,msm8960", .data = &match_data_krait },
 	{},
-- 
2.39.2

[PATCH v4 6/6] cpufreq: qcom-nvmem: enable core voltage scaling for MSM8960

[Dmitry Baryshkov]

Reuse APQ8064 config for MSM8960 to enable core voltage scaling.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-nvmem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
index 35e2610c9526..2590c673cd3b 100644
--- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -408,7 +408,7 @@ static const struct of_device_id qcom_cpufreq_match_list[] __initconst = {
 	{ .compatible = "qcom,ipq8064", .data = &match_data_krait },
 	{ .compatible = "qcom,apq8064", .data = &match_data_apq8064 },
 	{ .compatible = "qcom,msm8974", .data = &match_data_krait },
-	{ .compatible = "qcom,msm8960", .data = &match_data_krait },
+	{ .compatible = "qcom,msm8960", .data = &match_data_apq8064 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, qcom_cpufreq_match_list);
-- 
2.39.2

Re: [PATCH v4 0/6] cpufreq: qcom-nvmem: support apq8064 cpufreq scaling

[Konrad Dybcio]

On 27.08.2023 05:27, Dmitry Baryshkov wrote:
> This is a split of APQ8064 cpufreq series, as requested by Viresh. This
> series includes only opp and cpufreq parts, with the DT and soc parts
> being split to a separate patchset.
> 
> Each core has independent power and frequency control. Additionally the
> L2 cache is scaled to follow the CPU frequencies (failure to do so
> results in strange semi-random crashes).
> 
> Core voltage is controlled through the SAW2 devices, one for each core.
> The L2 has two regulators, vdd-mem and vdd-dig.
> 
No changelog?

Konrad

Re: [PATCH v4 0/6] cpufreq: qcom-nvmem: support apq8064 cpufreq scaling

[Dmitry Baryshkov]

On Mon, 28 Aug 2023 at 12:43, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>
> On 27.08.2023 05:27, Dmitry Baryshkov wrote:
> > This is a split of APQ8064 cpufreq series, as requested by Viresh. This
> > series includes only opp and cpufreq parts, with the DT and soc parts
> > being split to a separate patchset.
> >
> > Each core has independent power and frequency control. Additionally the
> > L2 cache is scaled to follow the CPU frequencies (failure to do so
> > results in strange semi-random crashes).
> >
> > Core voltage is controlled through the SAW2 devices, one for each core.
> > The L2 has two regulators, vdd-mem and vdd-dig.
> >
> No changelog?

Missed it while performing the split.

Changes since v3:
- Unrolled loops in krait_l2_config_regulators() (Konrad)

-- 
With best wishes
Dmitry

Re: [PATCH v4 5/6] cpufreq: qcom-nvmem: provide separate configuration data for apq8064

[Konrad Dybcio]

On 27.08.2023 05:28, Dmitry Baryshkov wrote:
> APQ8064 can scale core voltage according to the frequency needs. Rather
> than reusing the A/B format multiplexer, use a simple fuse parsing
> function and configure required regulator.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/cpufreq/qcom-cpufreq-nvmem.c | 49 ++++++++++++++++++++++++++--
>  1 file changed, 47 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> index 81c080b854fe..35e2610c9526 100644
> --- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
> +++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> @@ -26,6 +26,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_opp.h>
> +#include <linux/regulator/consumer.h>
>  #include <linux/slab.h>
>  #include <linux/soc/qcom/smem.h>
>  
> @@ -39,6 +40,7 @@ struct qcom_cpufreq_match_data {
>  			   char **pvs_name,
>  			   struct qcom_cpufreq_drv *drv);
>  	const char **genpd_names;
> +	const char * const *regulator_names;
>  };
>  
>  struct qcom_cpufreq_drv {
> @@ -203,6 +205,34 @@ static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
>  	return ret;
>  }
>  
> +static int qcom_cpufreq_apq8064_name_version(struct device *cpu_dev,
> +					     struct nvmem_cell *speedbin_nvmem,
> +					     char **pvs_name,
> +					     struct qcom_cpufreq_drv *drv)
> +{
> +	int speed = 0, pvs = 0;
> +	u8 *speedbin;
> +	size_t len;
> +	int ret = 0;
Unused, just return 0

> +
> +	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
> +	if (IS_ERR(speedbin))
> +		return PTR_ERR(speedbin);
> +
> +	if (len != 4)
> +		return -EINVAL;
> +
> +	get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
> +
> +	snprintf(*pvs_name, sizeof("speedXX-pvsXX"), "speed%d-pvs%d",
> +		 speed, pvs);
speed and pvs are both one hex digit long at best (see masking in
get_krait_bin_format_a)

Konrad

Re: [PATCH v4 2/6] cpufreq: qcom-nvmem: create L2 cache device

[Konrad Dybcio]

On 27.08.2023 05:27, Dmitry Baryshkov wrote:
> Scaling the frequencies on some of Qualcomm Krait platforms (e.g.
> APQ8064) also requires scaling of the L2 cache frequency. As the
> l2-cache device node is places under /cpus/ path, it is not created by
> default by the OF code. Create corresponding device here.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/cpufreq/qcom-cpufreq-nvmem.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> index 84d7033e5efe..f4c196ba4432 100644
> --- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
> +++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
> @@ -22,6 +22,7 @@
>  #include <linux/module.h>
>  #include <linux/nvmem-consumer.h>
>  #include <linux/of.h>
> +#include <linux/of_platform.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_opp.h>
> @@ -377,6 +378,7 @@ static int __init qcom_cpufreq_init(void)
>  {
>  	struct device_node *np = of_find_node_by_path("/");
>  	const struct of_device_id *match;
> +	unsigned int cpu;
>  	int ret;
>  
>  	if (!np)
> @@ -387,6 +389,25 @@ static int __init qcom_cpufreq_init(void)
>  	if (!match)
>  		return -ENODEV;
>  
> +	for_each_possible_cpu(cpu) {
> +		struct device *dev = get_cpu_device(cpu);
> +		struct device_node *cache;
> +		struct platform_device *pdev;
Aaaalmost reverse-Christmas-tree :D

> +
> +		cache = of_find_next_cache_node(dev->of_node);
> +		if (!cache)
> +			continue;
> +
> +		if (of_device_is_compatible(cache, "qcom,krait-l2-cache")) {
> +			pdev = of_platform_device_create(cache, NULL, NULL);
> +			if (IS_ERR(pdev))
> +				pr_err("%s: %pe, failed to create L2 cache node\n", __func__, pdev);
The return value should be null-checked instead


> +			/* the error is not fatal */
"This error"?

Konrad

Re: [PATCH v4 5/6] cpufreq: qcom-nvmem: provide separate configuration data for apq8064

[Dmitry Baryshkov]

On 28/08/2023 14:04, Konrad Dybcio wrote:
> On 27.08.2023 05:28, Dmitry Baryshkov wrote:
>> APQ8064 can scale core voltage according to the frequency needs. Rather
>> than reusing the A/B format multiplexer, use a simple fuse parsing
>> function and configure required regulator.
>>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> ---
>>   drivers/cpufreq/qcom-cpufreq-nvmem.c | 49 ++++++++++++++++++++++++++--
>>   1 file changed, 47 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/cpufreq/qcom-cpufreq-nvmem.c b/drivers/cpufreq/qcom-cpufreq-nvmem.c
>> index 81c080b854fe..35e2610c9526 100644
>> --- a/drivers/cpufreq/qcom-cpufreq-nvmem.c
>> +++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
>> @@ -26,6 +26,7 @@
>>   #include <linux/platform_device.h>
>>   #include <linux/pm_domain.h>
>>   #include <linux/pm_opp.h>
>> +#include <linux/regulator/consumer.h>
>>   #include <linux/slab.h>
>>   #include <linux/soc/qcom/smem.h>
>>   
>> @@ -39,6 +40,7 @@ struct qcom_cpufreq_match_data {
>>   			   char **pvs_name,
>>   			   struct qcom_cpufreq_drv *drv);
>>   	const char **genpd_names;
>> +	const char * const *regulator_names;
>>   };
>>   
>>   struct qcom_cpufreq_drv {
>> @@ -203,6 +205,34 @@ static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
>>   	return ret;
>>   }
>>   
>> +static int qcom_cpufreq_apq8064_name_version(struct device *cpu_dev,
>> +					     struct nvmem_cell *speedbin_nvmem,
>> +					     char **pvs_name,
>> +					     struct qcom_cpufreq_drv *drv)
>> +{
>> +	int speed = 0, pvs = 0;
>> +	u8 *speedbin;
>> +	size_t len;
>> +	int ret = 0;
> Unused, just return 0
> 
>> +
>> +	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
>> +	if (IS_ERR(speedbin))
>> +		return PTR_ERR(speedbin);
>> +
>> +	if (len != 4)
>> +		return -EINVAL;
>> +
>> +	get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
>> +
>> +	snprintf(*pvs_name, sizeof("speedXX-pvsXX"), "speed%d-pvs%d",
>> +		 speed, pvs);
> speed and pvs are both one hex digit long at best (see masking in
> get_krait_bin_format_a)

One hex translates to two decimal digits (0xf = 15).

> 
> Konrad

-- 
With best wishes
Dmitry