diff mbox series

[v4,5/6] soc: qcom: Add LLCC support for multi channel DDR

Message ID 20230623141806.13388-6-quic_kbajaj@quicinc.com
State New
Headers
Series soc: qcom: llcc: Add support for QDU1000/QRU1000 |

Commit Message

Komal Bajaj June 23, 2023, 2:18 p.m. UTC 
  Add LLCC support for multi channel DDR configuration
based on a feature register. Reading DDR channel
confiuration uses nvmem framework, so select the
dependency in Kconfig. Without this, there will be
errors while building the driver with COMPILE_TEST only.

Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
---
 drivers/soc/qcom/Kconfig     |  2 ++
 drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
 2 files changed, 32 insertions(+), 3 deletions(-)

Comments

Dmitry Baryshkov June 23, 2023, 2:26 p.m. UTC | #1 
On Fri, 23 Jun 2023 at 17:19, Komal Bajaj <quic_kbajaj@quicinc.com> wrote:
>
> Add LLCC support for multi channel DDR configuration
> based on a feature register. Reading DDR channel
> confiuration uses nvmem framework, so select the
> dependency in Kconfig. Without this, there will be
> errors while building the driver with COMPILE_TEST only.
>
> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
> ---
>  drivers/soc/qcom/Kconfig     |  2 ++
>  drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>  2 files changed, 32 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index a491718f8064..cc9ad41c63aa 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -64,6 +64,8 @@ config QCOM_LLCC
>         tristate "Qualcomm Technologies, Inc. LLCC driver"
>         depends on ARCH_QCOM || COMPILE_TEST
>         select REGMAP_MMIO
> +       select NVMEM

No need to select NVMEM. The used functions are stubbed if NVMEM is disabled

> +       select QCOM_SCM
>         help
>           Qualcomm Technologies, Inc. platform specific
>           Last Level Cache Controller(LLCC) driver for platforms such as,
> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
> index 6cf373da5df9..3c29612da1c5 100644
> --- a/drivers/soc/qcom/llcc-qcom.c
> +++ b/drivers/soc/qcom/llcc-qcom.c
> @@ -12,6 +12,7 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
> +#include <linux/nvmem-consumer.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/regmap.h>
> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>         return ret;
>  }
>
> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
> +{
> +       int ret;
> +
> +       ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
> +       if (ret == -ENOENT) {

|| ret == -EOPNOTSUPP ?

> +               *cfg_index = 0;
> +               return 0;
> +       }
> +
> +       return ret;
> +}
> +
>  static int qcom_llcc_remove(struct platform_device *pdev)
>  {
>         /* Set the global pointer to a error code to avoid referencing it */
> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>         struct device *dev = &pdev->dev;
>         int ret, i;
>         struct platform_device *llcc_edac;
> -       const struct qcom_llcc_config *cfg;
> +       const struct qcom_llcc_config *cfg, *entry;
>         const struct llcc_slice_config *llcc_cfg;
>         u32 sz;
> +       u8 cfg_index;
>         u32 version;
>         struct regmap *regmap;
> +       u32 num_entries = 0;
>
>         drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>         if (!drv_data) {
> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>
>         drv_data->version = version;
>
> -       llcc_cfg = cfg[0]->sct_data;
> -       sz = cfg[0]->size;
> +       ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
> +       if (ret)
> +               goto err;
> +
> +       for (entry = cfg; entry->sct_data; entry++, num_entries++)
> +               ;

Please add num_cfgs to the configuration data instead.

> +       if (cfg_index >= num_entries || cfg_index < 0) {

cfg_index is unsigned, so it can not be less than 0.

> +               ret = -EINVAL;
> +               goto err;
> +       }
> +
> +       llcc_cfg = cfg[cfg_index].sct_data;
> +       sz = cfg[cfg_index].size;
>
>         for (i = 0; i < sz; i++)
>                 if (llcc_cfg[i].slice_id > drv_data->max_slices)
> --
> 2.40.1
>
Konrad Dybcio June 23, 2023, 2:58 p.m. UTC | #2 
On 23.06.2023 16:18, Komal Bajaj wrote:
> Add LLCC support for multi channel DDR configuration
> based on a feature register. Reading DDR channel
> confiuration uses nvmem framework, so select the
> dependency in Kconfig. Without this, there will be
> errors while building the driver with COMPILE_TEST only.
> 
> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
> ---
>  drivers/soc/qcom/Kconfig     |  2 ++
>  drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>  2 files changed, 32 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index a491718f8064..cc9ad41c63aa 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -64,6 +64,8 @@ config QCOM_LLCC
>  	tristate "Qualcomm Technologies, Inc. LLCC driver"
>  	depends on ARCH_QCOM || COMPILE_TEST
>  	select REGMAP_MMIO
> +	select NVMEM
> +	select QCOM_SCM
>  	help
>  	  Qualcomm Technologies, Inc. platform specific
>  	  Last Level Cache Controller(LLCC) driver for platforms such as,
> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
> index 6cf373da5df9..3c29612da1c5 100644
> --- a/drivers/soc/qcom/llcc-qcom.c
> +++ b/drivers/soc/qcom/llcc-qcom.c
> @@ -12,6 +12,7 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
> +#include <linux/nvmem-consumer.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/regmap.h>
> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>  	return ret;
>  }
>  
> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
> +{
> +	int ret;
> +
> +	ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
> +	if (ret == -ENOENT) {
> +		*cfg_index = 0;
> +		return 0;
> +	}
> +
> +	return ret;
> +}
> +
>  static int qcom_llcc_remove(struct platform_device *pdev)
>  {
>  	/* Set the global pointer to a error code to avoid referencing it */
> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>  	struct device *dev = &pdev->dev;
>  	int ret, i;
>  	struct platform_device *llcc_edac;
> -	const struct qcom_llcc_config *cfg;
> +	const struct qcom_llcc_config *cfg, *entry;
>  	const struct llcc_slice_config *llcc_cfg;
>  	u32 sz;
> +	u8 cfg_index;
>  	u32 version;
>  	struct regmap *regmap;
> +	u32 num_entries = 0;
>  
>  	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>  	if (!drv_data) {
> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>  
>  	drv_data->version = version;
>  
> -	llcc_cfg = cfg[0]->sct_data;
> -	sz = cfg[0]->size;
> +	ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
> +	if (ret)
> +		goto err;
> +


> +	for (entry = cfg; entry->sct_data; entry++, num_entries++)
> +		;
> +	if (cfg_index >= num_entries || cfg_index < 0) {
cfg_index is an unsigned variable, it can never be < 0

> +		ret = -EINVAL;
> +		goto err;
> +	}
> +
if (cfg_index >= entry->size)? With that, you can also keep the config
entries non-0-terminated in the previous patch, saving a whole lot of RAM.

Konrad
> +	llcc_cfg = cfg[cfg_index].sct_data;
> +	sz = cfg[cfg_index].size;
>  
>  	for (i = 0; i < sz; i++)
>  		if (llcc_cfg[i].slice_id > drv_data->max_slices)
Komal Bajaj June 28, 2023, 8:52 a.m. UTC | #3 
On 6/23/2023 8:28 PM, Konrad Dybcio wrote:
> On 23.06.2023 16:18, Komal Bajaj wrote:
>> Add LLCC support for multi channel DDR configuration
>> based on a feature register. Reading DDR channel
>> confiuration uses nvmem framework, so select the
>> dependency in Kconfig. Without this, there will be
>> errors while building the driver with COMPILE_TEST only.
>>
>> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
>> ---
>>   drivers/soc/qcom/Kconfig     |  2 ++
>>   drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>>   2 files changed, 32 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>> index a491718f8064..cc9ad41c63aa 100644
>> --- a/drivers/soc/qcom/Kconfig
>> +++ b/drivers/soc/qcom/Kconfig
>> @@ -64,6 +64,8 @@ config QCOM_LLCC
>>   	tristate "Qualcomm Technologies, Inc. LLCC driver"
>>   	depends on ARCH_QCOM || COMPILE_TEST
>>   	select REGMAP_MMIO
>> +	select NVMEM
>> +	select QCOM_SCM
>>   	help
>>   	  Qualcomm Technologies, Inc. platform specific
>>   	  Last Level Cache Controller(LLCC) driver for platforms such as,
>> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
>> index 6cf373da5df9..3c29612da1c5 100644
>> --- a/drivers/soc/qcom/llcc-qcom.c
>> +++ b/drivers/soc/qcom/llcc-qcom.c
>> @@ -12,6 +12,7 @@
>>   #include <linux/kernel.h>
>>   #include <linux/module.h>
>>   #include <linux/mutex.h>
>> +#include <linux/nvmem-consumer.h>
>>   #include <linux/of.h>
>>   #include <linux/of_device.h>
>>   #include <linux/regmap.h>
>> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>>   	return ret;
>>   }
>>   
>> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
>> +{
>> +	int ret;
>> +
>> +	ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
>> +	if (ret == -ENOENT) {
>> +		*cfg_index = 0;
>> +		return 0;
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>>   static int qcom_llcc_remove(struct platform_device *pdev)
>>   {
>>   	/* Set the global pointer to a error code to avoid referencing it */
>> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>   	struct device *dev = &pdev->dev;
>>   	int ret, i;
>>   	struct platform_device *llcc_edac;
>> -	const struct qcom_llcc_config *cfg;
>> +	const struct qcom_llcc_config *cfg, *entry;
>>   	const struct llcc_slice_config *llcc_cfg;
>>   	u32 sz;
>> +	u8 cfg_index;
>>   	u32 version;
>>   	struct regmap *regmap;
>> +	u32 num_entries = 0;
>>   
>>   	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>>   	if (!drv_data) {
>> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>   
>>   	drv_data->version = version;
>>   
>> -	llcc_cfg = cfg[0]->sct_data;
>> -	sz = cfg[0]->size;
>> +	ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
>> +	if (ret)
>> +		goto err;
>> +
>
>> +	for (entry = cfg; entry->sct_data; entry++, num_entries++)
>> +		;
>> +	if (cfg_index >= num_entries || cfg_index < 0) {
> cfg_index is an unsigned variable, it can never be < 0

Okay, will remove this condition.

>
>> +		ret = -EINVAL;
>> +		goto err;
>> +	}
>> +
> if (cfg_index >= entry->size)? With that, you can also keep the config
> entries non-0-terminated in the previous patch, saving a whole lot of RAM.

entry->size represents the size of sct table whereas num_entries 
represents the number
of sct tables that we can have. And by this check we are validating the 
value read from the
fuse register. Am I understanding your comment correctly?

>
> Konrad
>> +	llcc_cfg = cfg[cfg_index].sct_data;
>> +	sz = cfg[cfg_index].size;
>>   
>>   	for (i = 0; i < sz; i++)
>>   		if (llcc_cfg[i].slice_id > drv_data->max_slices)
Konrad Dybcio June 28, 2023, 11:13 a.m. UTC | #4 
On 28.06.2023 10:52, Komal Bajaj wrote:
> 
> 
> On 6/23/2023 8:28 PM, Konrad Dybcio wrote:
>> On 23.06.2023 16:18, Komal Bajaj wrote:
>>> Add LLCC support for multi channel DDR configuration
>>> based on a feature register. Reading DDR channel
>>> confiuration uses nvmem framework, so select the
>>> dependency in Kconfig. Without this, there will be
>>> errors while building the driver with COMPILE_TEST only.
>>>
>>> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
>>> ---
>>>   drivers/soc/qcom/Kconfig     |  2 ++
>>>   drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>>>   2 files changed, 32 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>>> index a491718f8064..cc9ad41c63aa 100644
>>> --- a/drivers/soc/qcom/Kconfig
>>> +++ b/drivers/soc/qcom/Kconfig
>>> @@ -64,6 +64,8 @@ config QCOM_LLCC
>>>       tristate "Qualcomm Technologies, Inc. LLCC driver"
>>>       depends on ARCH_QCOM || COMPILE_TEST
>>>       select REGMAP_MMIO
>>> +    select NVMEM
>>> +    select QCOM_SCM
>>>       help
>>>         Qualcomm Technologies, Inc. platform specific
>>>         Last Level Cache Controller(LLCC) driver for platforms such as,
>>> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
>>> index 6cf373da5df9..3c29612da1c5 100644
>>> --- a/drivers/soc/qcom/llcc-qcom.c
>>> +++ b/drivers/soc/qcom/llcc-qcom.c
>>> @@ -12,6 +12,7 @@
>>>   #include <linux/kernel.h>
>>>   #include <linux/module.h>
>>>   #include <linux/mutex.h>
>>> +#include <linux/nvmem-consumer.h>
>>>   #include <linux/of.h>
>>>   #include <linux/of_device.h>
>>>   #include <linux/regmap.h>
>>> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>>>       return ret;
>>>   }
>>>   +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
>>> +{
>>> +    int ret;
>>> +
>>> +    ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
>>> +    if (ret == -ENOENT) {
>>> +        *cfg_index = 0;
>>> +        return 0;
>>> +    }
>>> +
>>> +    return ret;
>>> +}
>>> +
>>>   static int qcom_llcc_remove(struct platform_device *pdev)
>>>   {
>>>       /* Set the global pointer to a error code to avoid referencing it */
>>> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>       struct device *dev = &pdev->dev;
>>>       int ret, i;
>>>       struct platform_device *llcc_edac;
>>> -    const struct qcom_llcc_config *cfg;
>>> +    const struct qcom_llcc_config *cfg, *entry;
>>>       const struct llcc_slice_config *llcc_cfg;
>>>       u32 sz;
>>> +    u8 cfg_index;
>>>       u32 version;
>>>       struct regmap *regmap;
>>> +    u32 num_entries = 0;
>>>         drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>>>       if (!drv_data) {
>>> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>         drv_data->version = version;
>>>   -    llcc_cfg = cfg[0]->sct_data;
>>> -    sz = cfg[0]->size;
>>> +    ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
>>> +    if (ret)
>>> +        goto err;
>>> +
>>
>>> +    for (entry = cfg; entry->sct_data; entry++, num_entries++)
>>> +        ;
>>> +    if (cfg_index >= num_entries || cfg_index < 0) {
>> cfg_index is an unsigned variable, it can never be < 0
> 
> Okay, will remove this condition.
> 
>>
>>> +        ret = -EINVAL;
>>> +        goto err;
>>> +    }
>>> +
>> if (cfg_index >= entry->size)? With that, you can also keep the config
>> entries non-0-terminated in the previous patch, saving a whole lot of RAM.
> 
> entry->size represents the size of sct table whereas num_entries represents the number
> of sct tables that we can have. And by this check we are validating the value read from the
> fuse register. Am I understanding your comment correctly?
Oh you're right.

I still see room for improvement, though.

For example, you duplicate assigning need_llcc_cfg, reg_offset
and edac_reg_offset. You can add a new struct, like "sct_config" and add
a pointer to sct_config[] & the length of this array to qcom_llcc_config.

Konrad

> 
>>
>> Konrad
>>> +    llcc_cfg = cfg[cfg_index].sct_data;
>>> +    sz = cfg[cfg_index].size;
>>>         for (i = 0; i < sz; i++)
>>>           if (llcc_cfg[i].slice_id > drv_data->max_slices)
>
Dmitry Baryshkov June 28, 2023, 1:14 p.m. UTC | #5 
On 28/06/2023 11:45, Komal Bajaj wrote:

No HTML emails on public mailing lists, please.

> 
> 
> On 6/23/2023 7:56 PM, Dmitry Baryshkov wrote:
>> On Fri, 23 Jun 2023 at 17:19, Komal Bajaj<quic_kbajaj@quicinc.com>  wrote:
>>> Add LLCC support for multi channel DDR configuration
>>> based on a feature register. Reading DDR channel
>>> confiuration uses nvmem framework, so select the
>>> dependency in Kconfig. Without this, there will be
>>> errors while building the driver with COMPILE_TEST only.
>>>
>>> Signed-off-by: Komal Bajaj<quic_kbajaj@quicinc.com>
>>> ---
>>>   drivers/soc/qcom/Kconfig     |  2 ++
>>>   drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>>>   2 files changed, 32 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>>> index a491718f8064..cc9ad41c63aa 100644
>>> --- a/drivers/soc/qcom/Kconfig
>>> +++ b/drivers/soc/qcom/Kconfig
>>> @@ -64,6 +64,8 @@ config QCOM_LLCC
>>>          tristate "Qualcomm Technologies, Inc. LLCC driver"
>>>          depends on ARCH_QCOM || COMPILE_TEST
>>>          select REGMAP_MMIO
>>> +       select NVMEM
>> No need to select NVMEM. The used functions are stubbed if NVMEM is disabled
> 
> With the previous patch, where this config was not selected, below error 
> was flagged by kernel test robot -
> 
>     drivers/soc/qcom/llcc-qcom.c: In function 'qcom_llcc_get_cfg_index':
>      >> drivers/soc/qcom/llcc-qcom.c:951:15: error: implicit declaration
>     of function 'nvmem_cell_read_u8'; did you mean
>     'nvmem_cell_read_u64'? [-Werror=implicit-function-declaration]
>           951 |         ret = nvmem_cell_read_u8(&pdev->dev,
>     "multi_chan_ddr", cfg_index);
>               |               ^~~~~~~~~~~~~~~~~~
>               |               nvmem_cell_read_u64
>         cc1: some warnings being treated as errors

Judging from the rest of nvmem-consumer.h, it appears that not having 
stubs for this function is an omission. Please fix the header instead.

> 
>>> +       select QCOM_SCM
>>>          help
>>>            Qualcomm Technologies, Inc. platform specific
>>>            Last Level Cache Controller(LLCC) driver for platforms such as,
>>> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
>>> index 6cf373da5df9..3c29612da1c5 100644
>>> --- a/drivers/soc/qcom/llcc-qcom.c
>>> +++ b/drivers/soc/qcom/llcc-qcom.c
>>> @@ -12,6 +12,7 @@
>>>   #include <linux/kernel.h>
>>>   #include <linux/module.h>
>>>   #include <linux/mutex.h>
>>> +#include <linux/nvmem-consumer.h>
>>>   #include <linux/of.h>
>>>   #include <linux/of_device.h>
>>>   #include <linux/regmap.h>
>>> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>>>          return ret;
>>>   }
>>>
>>> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
>>> +{
>>> +       int ret;
>>> +
>>> +       ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
>>> +       if (ret == -ENOENT) {
>> || ret == -EOPNOTSUPP ?
> 
> Okay
> 
>>> +               *cfg_index = 0;
>>> +               return 0;
>>> +       }
>>> +
>>> +       return ret;
>>> +}
>>> +
>>>   static int qcom_llcc_remove(struct platform_device *pdev)
>>>   {
>>>          /* Set the global pointer to a error code to avoid referencing it */
>>> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>          struct device *dev = &pdev->dev;
>>>          int ret, i;
>>>          struct platform_device *llcc_edac;
>>> -       const struct qcom_llcc_config *cfg;
>>> +       const struct qcom_llcc_config *cfg, *entry;
>>>          const struct llcc_slice_config *llcc_cfg;
>>>          u32 sz;
>>> +       u8 cfg_index;
>>>          u32 version;
>>>          struct regmap *regmap;
>>> +       u32 num_entries = 0;
>>>
>>>          drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>>>          if (!drv_data) {
>>> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>
>>>          drv_data->version = version;
>>>
>>> -       llcc_cfg = cfg[0]->sct_data;
>>> -       sz = cfg[0]->size;
>>> +       ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
>>> +       if (ret)
>>> +               goto err;
>>> +
>>> +       for (entry = cfg; entry->sct_data; entry++, num_entries++)
>>> +               ;
>> Please add num_cfgs to the configuration data instead.
> 
> Shall I create a new wrapper struct having a field num_cfg and a pointer 
> to those cfgs
> because configuration data is itself an instance of "struct 
> qcom_llcc_config" and
> we can have multiple instances of it.

A wrapper struct is a better approach in my opinion.

> 
> 
>>> +       if (cfg_index >= num_entries || cfg_index < 0) {
>> cfg_index is unsigned, so it can not be less than 0.
> 
> Okay.
> 
>>> +               ret = -EINVAL;
>>> +               goto err;
>>> +       }
>>> +
>>> +       llcc_cfg = cfg[cfg_index].sct_data;
>>> +       sz = cfg[cfg_index].size;
>>>
>>>          for (i = 0; i < sz; i++)
>>>                  if (llcc_cfg[i].slice_id > drv_data->max_slices)
>>> --
>>> 2.40.1
>>>
>
Komal Bajaj June 30, 2023, 1:51 p.m. UTC | #6 
On 6/28/2023 4:43 PM, Konrad Dybcio wrote:
> On 28.06.2023 10:52, Komal Bajaj wrote:
>>
>> On 6/23/2023 8:28 PM, Konrad Dybcio wrote:
>>> On 23.06.2023 16:18, Komal Bajaj wrote:
>>>> Add LLCC support for multi channel DDR configuration
>>>> based on a feature register. Reading DDR channel
>>>> confiuration uses nvmem framework, so select the
>>>> dependency in Kconfig. Without this, there will be
>>>> errors while building the driver with COMPILE_TEST only.
>>>>
>>>> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
>>>> ---
>>>>    drivers/soc/qcom/Kconfig     |  2 ++
>>>>    drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>>>>    2 files changed, 32 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>>>> index a491718f8064..cc9ad41c63aa 100644
>>>> --- a/drivers/soc/qcom/Kconfig
>>>> +++ b/drivers/soc/qcom/Kconfig
>>>> @@ -64,6 +64,8 @@ config QCOM_LLCC
>>>>        tristate "Qualcomm Technologies, Inc. LLCC driver"
>>>>        depends on ARCH_QCOM || COMPILE_TEST
>>>>        select REGMAP_MMIO
>>>> +    select NVMEM
>>>> +    select QCOM_SCM
>>>>        help
>>>>          Qualcomm Technologies, Inc. platform specific
>>>>          Last Level Cache Controller(LLCC) driver for platforms such as,
>>>> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
>>>> index 6cf373da5df9..3c29612da1c5 100644
>>>> --- a/drivers/soc/qcom/llcc-qcom.c
>>>> +++ b/drivers/soc/qcom/llcc-qcom.c
>>>> @@ -12,6 +12,7 @@
>>>>    #include <linux/kernel.h>
>>>>    #include <linux/module.h>
>>>>    #include <linux/mutex.h>
>>>> +#include <linux/nvmem-consumer.h>
>>>>    #include <linux/of.h>
>>>>    #include <linux/of_device.h>
>>>>    #include <linux/regmap.h>
>>>> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>>>>        return ret;
>>>>    }
>>>>    +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
>>>> +{
>>>> +    int ret;
>>>> +
>>>> +    ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
>>>> +    if (ret == -ENOENT) {
>>>> +        *cfg_index = 0;
>>>> +        return 0;
>>>> +    }
>>>> +
>>>> +    return ret;
>>>> +}
>>>> +
>>>>    static int qcom_llcc_remove(struct platform_device *pdev)
>>>>    {
>>>>        /* Set the global pointer to a error code to avoid referencing it */
>>>> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>>        struct device *dev = &pdev->dev;
>>>>        int ret, i;
>>>>        struct platform_device *llcc_edac;
>>>> -    const struct qcom_llcc_config *cfg;
>>>> +    const struct qcom_llcc_config *cfg, *entry;
>>>>        const struct llcc_slice_config *llcc_cfg;
>>>>        u32 sz;
>>>> +    u8 cfg_index;
>>>>        u32 version;
>>>>        struct regmap *regmap;
>>>> +    u32 num_entries = 0;
>>>>          drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>>>>        if (!drv_data) {
>>>> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>>>>          drv_data->version = version;
>>>>    -    llcc_cfg = cfg[0]->sct_data;
>>>> -    sz = cfg[0]->size;
>>>> +    ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
>>>> +    if (ret)
>>>> +        goto err;
>>>> +
>>>> +    for (entry = cfg; entry->sct_data; entry++, num_entries++)
>>>> +        ;
>>>> +    if (cfg_index >= num_entries || cfg_index < 0) {
>>> cfg_index is an unsigned variable, it can never be < 0
>> Okay, will remove this condition.
>>
>>>> +        ret = -EINVAL;
>>>> +        goto err;
>>>> +    }
>>>> +
>>> if (cfg_index >= entry->size)? With that, you can also keep the config
>>> entries non-0-terminated in the previous patch, saving a whole lot of RAM.
>> entry->size represents the size of sct table whereas num_entries represents the number
>> of sct tables that we can have. And by this check we are validating the value read from the
>> fuse register. Am I understanding your comment correctly?
> Oh you're right.
>
> I still see room for improvement, though.
>
> For example, you duplicate assigning need_llcc_cfg, reg_offset
> and edac_reg_offset. You can add a new struct, like "sct_config" and add
> a pointer to sct_config[] & the length of this array to qcom_llcc_config.
>
> Konrad

Okay, will follow this approach.

>
>>> Konrad
>>>> +    llcc_cfg = cfg[cfg_index].sct_data;
>>>> +    sz = cfg[cfg_index].size;
>>>>          for (i = 0; i < sz; i++)
>>>>            if (llcc_cfg[i].slice_id > drv_data->max_slices)
Komal Bajaj June 30, 2023, 1:54 p.m. UTC | #7 
On 6/28/2023 6:44 PM, Dmitry Baryshkov wrote:
> On 28/06/2023 11:45, Komal Bajaj wrote:
>
> No HTML emails on public mailing lists, please.
>
>>
>>
>> On 6/23/2023 7:56 PM, Dmitry Baryshkov wrote:
>>> On Fri, 23 Jun 2023 at 17:19, Komal Bajaj<quic_kbajaj@quicinc.com>  
>>> wrote:
>>>> Add LLCC support for multi channel DDR configuration
>>>> based on a feature register. Reading DDR channel
>>>> confiuration uses nvmem framework, so select the
>>>> dependency in Kconfig. Without this, there will be
>>>> errors while building the driver with COMPILE_TEST only.
>>>>
>>>> Signed-off-by: Komal Bajaj<quic_kbajaj@quicinc.com>
>>>> ---
>>>>   drivers/soc/qcom/Kconfig     |  2 ++
>>>>   drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>>>>   2 files changed, 32 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>>>> index a491718f8064..cc9ad41c63aa 100644
>>>> --- a/drivers/soc/qcom/Kconfig
>>>> +++ b/drivers/soc/qcom/Kconfig
>>>> @@ -64,6 +64,8 @@ config QCOM_LLCC
>>>>          tristate "Qualcomm Technologies, Inc. LLCC driver"
>>>>          depends on ARCH_QCOM || COMPILE_TEST
>>>>          select REGMAP_MMIO
>>>> +       select NVMEM
>>> No need to select NVMEM. The used functions are stubbed if NVMEM is 
>>> disabled
>>
>> With the previous patch, where this config was not selected, below 
>> error was flagged by kernel test robot -
>>
>>     drivers/soc/qcom/llcc-qcom.c: In function 'qcom_llcc_get_cfg_index':
>>      >> drivers/soc/qcom/llcc-qcom.c:951:15: error: implicit declaration
>>     of function 'nvmem_cell_read_u8'; did you mean
>>     'nvmem_cell_read_u64'? [-Werror=implicit-function-declaration]
>>           951 |         ret = nvmem_cell_read_u8(&pdev->dev,
>>     "multi_chan_ddr", cfg_index);
>>               |               ^~~~~~~~~~~~~~~~~~
>>               |               nvmem_cell_read_u64
>>         cc1: some warnings being treated as errors
>
> Judging from the rest of nvmem-consumer.h, it appears that not having 
> stubs for this function is an omission. Please fix the header instead.

Okay, I will add the stub for this function in the header.

>
>>
>>>> +       select QCOM_SCM
>>>>          help
>>>>            Qualcomm Technologies, Inc. platform specific
>>>>            Last Level Cache Controller(LLCC) driver for platforms 
>>>> such as,
>>>> diff --git a/drivers/soc/qcom/llcc-qcom.c 
>>>> b/drivers/soc/qcom/llcc-qcom.c
>>>> index 6cf373da5df9..3c29612da1c5 100644
>>>> --- a/drivers/soc/qcom/llcc-qcom.c
>>>> +++ b/drivers/soc/qcom/llcc-qcom.c
>>>> @@ -12,6 +12,7 @@
>>>>   #include <linux/kernel.h>
>>>>   #include <linux/module.h>
>>>>   #include <linux/mutex.h>
>>>> +#include <linux/nvmem-consumer.h>
>>>>   #include <linux/of.h>
>>>>   #include <linux/of_device.h>
>>>>   #include <linux/regmap.h>
>>>> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct 
>>>> platform_device *pdev,
>>>>          return ret;
>>>>   }
>>>>
>>>> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, 
>>>> u8 *cfg_index)
>>>> +{
>>>> +       int ret;
>>>> +
>>>> +       ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", 
>>>> cfg_index);
>>>> +       if (ret == -ENOENT) {
>>> || ret == -EOPNOTSUPP ?
>>
>> Okay
>>
>>>> +               *cfg_index = 0;
>>>> +               return 0;
>>>> +       }
>>>> +
>>>> +       return ret;
>>>> +}
>>>> +
>>>>   static int qcom_llcc_remove(struct platform_device *pdev)
>>>>   {
>>>>          /* Set the global pointer to a error code to avoid 
>>>> referencing it */
>>>> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct 
>>>> platform_device *pdev)
>>>>          struct device *dev = &pdev->dev;
>>>>          int ret, i;
>>>>          struct platform_device *llcc_edac;
>>>> -       const struct qcom_llcc_config *cfg;
>>>> +       const struct qcom_llcc_config *cfg, *entry;
>>>>          const struct llcc_slice_config *llcc_cfg;
>>>>          u32 sz;
>>>> +       u8 cfg_index;
>>>>          u32 version;
>>>>          struct regmap *regmap;
>>>> +       u32 num_entries = 0;
>>>>
>>>>          drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>>>>          if (!drv_data) {
>>>> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct 
>>>> platform_device *pdev)
>>>>
>>>>          drv_data->version = version;
>>>>
>>>> -       llcc_cfg = cfg[0]->sct_data;
>>>> -       sz = cfg[0]->size;
>>>> +       ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
>>>> +       if (ret)
>>>> +               goto err;
>>>> +
>>>> +       for (entry = cfg; entry->sct_data; entry++, num_entries++)
>>>> +               ;
>>> Please add num_cfgs to the configuration data instead.
>>
>> Shall I create a new wrapper struct having a field num_cfg and a 
>> pointer to those cfgs
>> because configuration data is itself an instance of "struct 
>> qcom_llcc_config" and
>> we can have multiple instances of it.
>
> A wrapper struct is a better approach in my opinion.

Okay, will follow this approach then.

Thanks
Komal
>
>>
>>
>>>> +       if (cfg_index >= num_entries || cfg_index < 0) {
>>> cfg_index is unsigned, so it can not be less than 0.
>>
>> Okay.
>>
>>>> +               ret = -EINVAL;
>>>> +               goto err;
>>>> +       }
>>>> +
>>>> +       llcc_cfg = cfg[cfg_index].sct_data;
>>>> +       sz = cfg[cfg_index].size;
>>>>
>>>>          for (i = 0; i < sz; i++)
>>>>                  if (llcc_cfg[i].slice_id > drv_data->max_slices)
>>>> -- 
>>>> 2.40.1
>>>>
>>
>
Bjorn Andersson June 30, 2023, 8:40 p.m. UTC | #8 
On Fri, Jun 23, 2023 at 07:48:05PM +0530, Komal Bajaj wrote:
> Add LLCC support for multi channel DDR configuration
> based on a feature register. Reading DDR channel
> confiuration uses nvmem framework, so select the
> dependency in Kconfig. Without this, there will be
> errors while building the driver with COMPILE_TEST only.

You may drop the last sentence, I don't think it's entirely correct.

> 
> Signed-off-by: Komal Bajaj <quic_kbajaj@quicinc.com>
> ---
>  drivers/soc/qcom/Kconfig     |  2 ++
>  drivers/soc/qcom/llcc-qcom.c | 33 ++++++++++++++++++++++++++++++---
>  2 files changed, 32 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index a491718f8064..cc9ad41c63aa 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -64,6 +64,8 @@ config QCOM_LLCC
>  	tristate "Qualcomm Technologies, Inc. LLCC driver"
>  	depends on ARCH_QCOM || COMPILE_TEST
>  	select REGMAP_MMIO
> +	select NVMEM
> +	select QCOM_SCM

I don't see anything your patch that warrants adding QCOM_SCM here,
is it needed, should it be a separate commit?

>  	help
>  	  Qualcomm Technologies, Inc. platform specific
>  	  Last Level Cache Controller(LLCC) driver for platforms such as,
> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
> index 6cf373da5df9..3c29612da1c5 100644
> --- a/drivers/soc/qcom/llcc-qcom.c
> +++ b/drivers/soc/qcom/llcc-qcom.c
> @@ -12,6 +12,7 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
> +#include <linux/nvmem-consumer.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/regmap.h>
> @@ -943,6 +944,19 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
>  	return ret;
>  }
>  
> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
> +{
> +	int ret;
> +
> +	ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
> +	if (ret == -ENOENT) {
> +		*cfg_index = 0;
> +		return 0;
> +	}
> +
> +	return ret;
> +}
> +
>  static int qcom_llcc_remove(struct platform_device *pdev)
>  {
>  	/* Set the global pointer to a error code to avoid referencing it */
> @@ -975,11 +989,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>  	struct device *dev = &pdev->dev;
>  	int ret, i;
>  	struct platform_device *llcc_edac;
> -	const struct qcom_llcc_config *cfg;
> +	const struct qcom_llcc_config *cfg, *entry;
>  	const struct llcc_slice_config *llcc_cfg;
>  	u32 sz;
> +	u8 cfg_index;
>  	u32 version;
>  	struct regmap *regmap;
> +	u32 num_entries = 0;
>  
>  	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
>  	if (!drv_data) {
> @@ -1040,8 +1056,19 @@ static int qcom_llcc_probe(struct platform_device *pdev)
>  
>  	drv_data->version = version;
>  
> -	llcc_cfg = cfg[0]->sct_data;
> -	sz = cfg[0]->size;
> +	ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
> +	if (ret)
> +		goto err;
> +
> +	for (entry = cfg; entry->sct_data; entry++, num_entries++)
> +		;

This is still unnecessarily "clever":
"For each valid entry, do nothing, while incrementing num_entries".

How about just writing:
"For each valid entry, increment num_entries"

	for (entry = cfg; entry->sct_data; entry++)
		num_entries++;


> +	if (cfg_index >= num_entries || cfg_index < 0) {

cfg_index is an unsiged number, so it's unlikely to be negative.

Also, "cfg_index" and "num_entries" are values in the same domain, so
keeping their names related is beneficial - i.e. rename num_entries to
num_cfgs.

Regards,
Bjorn

> +		ret = -EINVAL;
> +		goto err;
> +	}
> +
> +	llcc_cfg = cfg[cfg_index].sct_data;
> +	sz = cfg[cfg_index].size;
>  
>  	for (i = 0; i < sz; i++)
>  		if (llcc_cfg[i].slice_id > drv_data->max_slices)
> -- 
> 2.40.1
>
diff mbox series

Patch

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index a491718f8064..cc9ad41c63aa 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -64,6 +64,8 @@  config QCOM_LLCC
 	tristate "Qualcomm Technologies, Inc. LLCC driver"
 	depends on ARCH_QCOM || COMPILE_TEST
 	select REGMAP_MMIO
+	select NVMEM
+	select QCOM_SCM
 	help
 	  Qualcomm Technologies, Inc. platform specific
 	  Last Level Cache Controller(LLCC) driver for platforms such as,
diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
index 6cf373da5df9..3c29612da1c5 100644
--- a/drivers/soc/qcom/llcc-qcom.c
+++ b/drivers/soc/qcom/llcc-qcom.c
@@ -12,6 +12,7 @@ 
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/nvmem-consumer.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/regmap.h>
@@ -943,6 +944,19 @@  static int qcom_llcc_cfg_program(struct platform_device *pdev,
 	return ret;
 }
 
+static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u8 *cfg_index)
+{
+	int ret;
+
+	ret = nvmem_cell_read_u8(&pdev->dev, "multi-chan-ddr", cfg_index);
+	if (ret == -ENOENT) {
+		*cfg_index = 0;
+		return 0;
+	}
+
+	return ret;
+}
+
 static int qcom_llcc_remove(struct platform_device *pdev)
 {
 	/* Set the global pointer to a error code to avoid referencing it */
@@ -975,11 +989,13 @@  static int qcom_llcc_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	int ret, i;
 	struct platform_device *llcc_edac;
-	const struct qcom_llcc_config *cfg;
+	const struct qcom_llcc_config *cfg, *entry;
 	const struct llcc_slice_config *llcc_cfg;
 	u32 sz;
+	u8 cfg_index;
 	u32 version;
 	struct regmap *regmap;
+	u32 num_entries = 0;
 
 	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
 	if (!drv_data) {
@@ -1040,8 +1056,19 @@  static int qcom_llcc_probe(struct platform_device *pdev)
 
 	drv_data->version = version;
 
-	llcc_cfg = cfg[0]->sct_data;
-	sz = cfg[0]->size;
+	ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
+	if (ret)
+		goto err;
+
+	for (entry = cfg; entry->sct_data; entry++, num_entries++)
+		;
+	if (cfg_index >= num_entries || cfg_index < 0) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	llcc_cfg = cfg[cfg_index].sct_data;
+	sz = cfg[cfg_index].size;
 
 	for (i = 0; i < sz; i++)
 		if (llcc_cfg[i].slice_id > drv_data->max_slices)