[v4,4/8] tpm: redefine read_log() to handle ACPI/OF at runtime

Commit Message

Nayna Sept. 28, 2016, 8:34 a.m. UTC

Currently, read_log() has two implementations: one for ACPI platforms
and the other for OF platforms. The proper one is selected at compile
time using Kconfig and #ifdef in the Makefile, which is not the
recommended approach.

This patch removes the #ifdef in the Makefile by defining a single
read_log() method, which checks for ACPI/OF event log properties at
runtime.

Suggested-by: Jason Gunthorpe <[e-mail]>
Signed-off-by: Nayna Jain <[e-mail]>
Reviewed-by: Jason Gunthorpe <[e-mail]>
---
 drivers/char/tpm/Makefile       | 14 ++++----------
 drivers/char/tpm/tpm_acpi.c     |  9 ++-------
 drivers/char/tpm/tpm_eventlog.c | 18 ++++++++++++++++++
 drivers/char/tpm/tpm_eventlog.h | 22 +++++++++++++---------
 drivers/char/tpm/tpm_of.c       |  8 ++------
 5 files changed, 39 insertions(+), 32 deletions(-)

Comments

Jarkko Sakkinen Sept. 30, 2016, 7:05 p.m. UTC | #1

On Wed, Sep 28, 2016 at 04:34:38AM -0400, Nayna Jain wrote:
> Currently, read_log() has two implementations: one for ACPI platforms
> and the other for OF platforms. The proper one is selected at compile
> time using Kconfig and #ifdef in the Makefile, which is not the
> recommended approach.
> 
> This patch removes the #ifdef in the Makefile by defining a single
> read_log() method, which checks for ACPI/OF event log properties at
> runtime.
> 
> Suggested-by: Jason Gunthorpe <[e-mail]>
> Signed-off-by: Nayna Jain <[e-mail]>
> Reviewed-by: Jason Gunthorpe <[e-mail]>
> ---
>  drivers/char/tpm/Makefile       | 14 ++++----------
>  drivers/char/tpm/tpm_acpi.c     |  9 ++-------
>  drivers/char/tpm/tpm_eventlog.c | 18 ++++++++++++++++++
>  drivers/char/tpm/tpm_eventlog.h | 22 +++++++++++++---------
>  drivers/char/tpm/tpm_of.c       |  8 ++------
>  5 files changed, 39 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
> index a385fb8..a05b1eb 100644
> --- a/drivers/char/tpm/Makefile
> +++ b/drivers/char/tpm/Makefile
> @@ -2,16 +2,10 @@
>  # Makefile for the kernel tpm device drivers.
>  #
>  obj-$(CONFIG_TCG_TPM) += tpm.o
> -tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
> -tpm-$(CONFIG_ACPI) += tpm_ppi.o
> -
> -ifdef CONFIG_ACPI
> -	tpm-y += tpm_eventlog.o tpm_acpi.o
> -else
> -ifdef CONFIG_TCG_IBMVTPM
> -	tpm-y += tpm_eventlog.o tpm_of.o
> -endif
> -endif
> +tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
> +		tpm_eventlog.o
> +tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
> +tpm-$(CONFIG_OF) += tpm_of.o
>  obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
>  obj-$(CONFIG_TCG_TIS) += tpm_tis.o
>  obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
> diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
> index 4d6c2d7..859bdba 100644
> --- a/drivers/char/tpm/tpm_acpi.c
> +++ b/drivers/char/tpm/tpm_acpi.c
> @@ -6,6 +6,7 @@
>   *	Stefan Berger <[e-mail]>
>   *	Reiner Sailer <[e-mail]>
>   *	Kylene Hall <[e-mail]>
> + *	Nayna Jain <[e-mail]>
>   *
>   * Maintained by: <[e-mail]>
>   *
> @@ -45,7 +46,7 @@ struct acpi_tcpa {
>  };
>  
>  /* read binary bios log */
> -int read_log(struct tpm_chip *chip)
> +int read_log_acpi(struct tpm_chip *chip)
>  {
>  	struct acpi_tcpa *buff;
>  	acpi_status status;
> @@ -54,12 +55,6 @@ int read_log(struct tpm_chip *chip)
>  	struct tpm_bios_log *log;
>  
>  	log = &chip->log;
> -	if (log->bios_event_log != NULL) {
> -		printk(KERN_ERR
> -		       "%s: ERROR - Eventlog already initialized\n",
> -		       __func__);
> -		return -EFAULT;
> -	}
>  
>  	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
>  	status = acpi_get_table(ACPI_SIG_TCPA, 1,
> diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
> index a8cd4a1..c327089 100644
> --- a/drivers/char/tpm/tpm_eventlog.c
> +++ b/drivers/char/tpm/tpm_eventlog.c
> @@ -346,6 +346,24 @@ static int is_bad(void *p)
>  	return 0;
>  }
>  
> +int read_log(struct tpm_chip *chip)
> +{
> +	int rc;
> +
> +	if (chip->log.bios_event_log != NULL) {
> +		dev_dbg(&chip->dev, "%s: ERROR - Eventlog already initialized\n",
> +			__func__);
> +		return -EFAULT;
> +	}
> +
> +	rc = read_log_acpi(chip);
> +	if ((rc == 0) || (rc == -ENOMEM))
> +		return rc;
> +	rc = read_log_of(chip);
> +	return rc;
> +
> +}

I'm wondering if it is a better idea to leverage tpm_class_ops? This
would be kind of cool idea to implement this because then the decision
to support event log could be leveraged to the driver level.

If the event_log pointer is NULL, then event log is not supported.

/Jarkko

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Nayna Oct. 6, 2016, 8:38 p.m. UTC | #2

On 10/01/2016 12:35 AM, Jarkko Sakkinen wrote:
> On Wed, Sep 28, 2016 at 04:34:38AM -0400, Nayna Jain wrote:
>> Currently, read_log() has two implementations: one for ACPI platforms
>> and the other for OF platforms. The proper one is selected at compile
>> time using Kconfig and #ifdef in the Makefile, which is not the
>> recommended approach.
>>
>> This patch removes the #ifdef in the Makefile by defining a single
>> read_log() method, which checks for ACPI/OF event log properties at
>> runtime.
>>
>> Suggested-by: Jason Gunthorpe <[e-mail]>
>> Signed-off-by: Nayna Jain <[e-mail]>
>> Reviewed-by: Jason Gunthorpe <[e-mail]>
>> ---
>>   drivers/char/tpm/Makefile       | 14 ++++----------
>>   drivers/char/tpm/tpm_acpi.c     |  9 ++-------
>>   drivers/char/tpm/tpm_eventlog.c | 18 ++++++++++++++++++
>>   drivers/char/tpm/tpm_eventlog.h | 22 +++++++++++++---------
>>   drivers/char/tpm/tpm_of.c       |  8 ++------
>>   5 files changed, 39 insertions(+), 32 deletions(-)
>>
>> diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
>> index a385fb8..a05b1eb 100644
>> --- a/drivers/char/tpm/Makefile
>> +++ b/drivers/char/tpm/Makefile
>> @@ -2,16 +2,10 @@
>>   # Makefile for the kernel tpm device drivers.
>>   #
>>   obj-$(CONFIG_TCG_TPM) += tpm.o
>> -tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
>> -tpm-$(CONFIG_ACPI) += tpm_ppi.o
>> -
>> -ifdef CONFIG_ACPI
>> -	tpm-y += tpm_eventlog.o tpm_acpi.o
>> -else
>> -ifdef CONFIG_TCG_IBMVTPM
>> -	tpm-y += tpm_eventlog.o tpm_of.o
>> -endif
>> -endif
>> +tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
>> +		tpm_eventlog.o
>> +tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
>> +tpm-$(CONFIG_OF) += tpm_of.o
>>   obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
>>   obj-$(CONFIG_TCG_TIS) += tpm_tis.o
>>   obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
>> diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
>> index 4d6c2d7..859bdba 100644
>> --- a/drivers/char/tpm/tpm_acpi.c
>> +++ b/drivers/char/tpm/tpm_acpi.c
>> @@ -6,6 +6,7 @@
>>    *	Stefan Berger <[e-mail]>
>>    *	Reiner Sailer <[e-mail]>
>>    *	Kylene Hall <[e-mail]>
>> + *	Nayna Jain <[e-mail]>
>>    *
>>    * Maintained by: <[e-mail]>
>>    *
>> @@ -45,7 +46,7 @@ struct acpi_tcpa {
>>   };
>>
>>   /* read binary bios log */
>> -int read_log(struct tpm_chip *chip)
>> +int read_log_acpi(struct tpm_chip *chip)
>>   {
>>   	struct acpi_tcpa *buff;
>>   	acpi_status status;
>> @@ -54,12 +55,6 @@ int read_log(struct tpm_chip *chip)
>>   	struct tpm_bios_log *log;
>>
>>   	log = &chip->log;
>> -	if (log->bios_event_log != NULL) {
>> -		printk(KERN_ERR
>> -		       "%s: ERROR - Eventlog already initialized\n",
>> -		       __func__);
>> -		return -EFAULT;
>> -	}
>>
>>   	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
>>   	status = acpi_get_table(ACPI_SIG_TCPA, 1,
>> diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
>> index a8cd4a1..c327089 100644
>> --- a/drivers/char/tpm/tpm_eventlog.c
>> +++ b/drivers/char/tpm/tpm_eventlog.c
>> @@ -346,6 +346,24 @@ static int is_bad(void *p)
>>   	return 0;
>>   }
>>
>> +int read_log(struct tpm_chip *chip)
>> +{
>> +	int rc;
>> +
>> +	if (chip->log.bios_event_log != NULL) {
>> +		dev_dbg(&chip->dev, "%s: ERROR - Eventlog already initialized\n",
>> +			__func__);
>> +		return -EFAULT;
>> +	}
>> +
>> +	rc = read_log_acpi(chip);
>> +	if ((rc == 0) || (rc == -ENOMEM))
>> +		return rc;
>> +	rc = read_log_of(chip);
>> +	return rc;
>> +
>> +}
>
> I'm wondering if it is a better idea to leverage tpm_class_ops? This
> would be kind of cool idea to implement this because then the decision
> to support event log could be leveraged to the driver level.

Can you please explain me this bit more ?

For eg, when we say driver level.. does that mean to the level of tis, 
nuvoton ?

And what type of decision ? I mean like decision to create securityfs 
setup for userspace to read eventlog ? or there are other things ?

>
> If the event_log pointer is NULL, then event log is not supported.

Yeah, sure will fix this.

Thanks & Regards,
     - Nayna
>
> /Jarkko
>


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Nayna Oct. 9, 2016, 11:29 a.m. UTC | #3

On 10/07/2016 02:08 AM, Nayna wrote:
>
>
> On 10/01/2016 12:35 AM, Jarkko Sakkinen wrote:
>> On Wed, Sep 28, 2016 at 04:34:38AM -0400, Nayna Jain wrote:
>>> Currently, read_log() has two implementations: one for ACPI platforms
>>> and the other for OF platforms. The proper one is selected at compile
>>> time using Kconfig and #ifdef in the Makefile, which is not the
>>> recommended approach.
>>>
>>> This patch removes the #ifdef in the Makefile by defining a single
>>> read_log() method, which checks for ACPI/OF event log properties at
>>> runtime.
>>>
>>> Suggested-by: Jason Gunthorpe <[e-mail]>
>>> Signed-off-by: Nayna Jain <[e-mail]>
>>> Reviewed-by: Jason Gunthorpe <[e-mail]>
>>> ---
>>>    drivers/char/tpm/Makefile       | 14 ++++----------
>>>    drivers/char/tpm/tpm_acpi.c     |  9 ++-------
>>>    drivers/char/tpm/tpm_eventlog.c | 18 ++++++++++++++++++
>>>    drivers/char/tpm/tpm_eventlog.h | 22 +++++++++++++---------
>>>    drivers/char/tpm/tpm_of.c       |  8 ++------
>>>    5 files changed, 39 insertions(+), 32 deletions(-)
>>>
>>> diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
>>> index a385fb8..a05b1eb 100644
>>> --- a/drivers/char/tpm/Makefile
>>> +++ b/drivers/char/tpm/Makefile
>>> @@ -2,16 +2,10 @@
>>>    # Makefile for the kernel tpm device drivers.
>>>    #
>>>    obj-$(CONFIG_TCG_TPM) += tpm.o
>>> -tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
>>> -tpm-$(CONFIG_ACPI) += tpm_ppi.o
>>> -
>>> -ifdef CONFIG_ACPI
>>> -	tpm-y += tpm_eventlog.o tpm_acpi.o
>>> -else
>>> -ifdef CONFIG_TCG_IBMVTPM
>>> -	tpm-y += tpm_eventlog.o tpm_of.o
>>> -endif
>>> -endif
>>> +tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
>>> +		tpm_eventlog.o
>>> +tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
>>> +tpm-$(CONFIG_OF) += tpm_of.o
>>>    obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
>>>    obj-$(CONFIG_TCG_TIS) += tpm_tis.o
>>>    obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
>>> diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
>>> index 4d6c2d7..859bdba 100644
>>> --- a/drivers/char/tpm/tpm_acpi.c
>>> +++ b/drivers/char/tpm/tpm_acpi.c
>>> @@ -6,6 +6,7 @@
>>>     *	Stefan Berger <[e-mail]>
>>>     *	Reiner Sailer <[e-mail]>
>>>     *	Kylene Hall <[e-mail]>
>>> + *	Nayna Jain <[e-mail]>
>>>     *
>>>     * Maintained by: <[e-mail]>
>>>     *
>>> @@ -45,7 +46,7 @@ struct acpi_tcpa {
>>>    };
>>>
>>>    /* read binary bios log */
>>> -int read_log(struct tpm_chip *chip)
>>> +int read_log_acpi(struct tpm_chip *chip)
>>>    {
>>>    	struct acpi_tcpa *buff;
>>>    	acpi_status status;
>>> @@ -54,12 +55,6 @@ int read_log(struct tpm_chip *chip)
>>>    	struct tpm_bios_log *log;
>>>
>>>    	log = &chip->log;
>>> -	if (log->bios_event_log != NULL) {
>>> -		printk(KERN_ERR
>>> -		       "%s: ERROR - Eventlog already initialized\n",
>>> -		       __func__);
>>> -		return -EFAULT;
>>> -	}
>>>
>>>    	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
>>>    	status = acpi_get_table(ACPI_SIG_TCPA, 1,
>>> diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
>>> index a8cd4a1..c327089 100644
>>> --- a/drivers/char/tpm/tpm_eventlog.c
>>> +++ b/drivers/char/tpm/tpm_eventlog.c
>>> @@ -346,6 +346,24 @@ static int is_bad(void *p)
>>>    	return 0;
>>>    }
>>>
>>> +int read_log(struct tpm_chip *chip)
>>> +{
>>> +	int rc;
>>> +
>>> +	if (chip->log.bios_event_log != NULL) {
>>> +		dev_dbg(&chip->dev, "%s: ERROR - Eventlog already initialized\n",
>>> +			__func__);
>>> +		return -EFAULT;
>>> +	}
>>> +
>>> +	rc = read_log_acpi(chip);
>>> +	if ((rc == 0) || (rc == -ENOMEM))
>>> +		return rc;
>>> +	rc = read_log_of(chip);
>>> +	return rc;
>>> +
>>> +}
>>
>> I'm wondering if it is a better idea to leverage tpm_class_ops? This
>> would be kind of cool idea to implement this because then the decision
>> to support event log could be leveraged to the driver level.
>
> Can you please explain me this bit more ?
>
> For eg, when we say driver level.. does that mean to the level of tis,
> nuvoton ?
>
> And what type of decision ? I mean like decision to create securityfs
> setup for userspace to read eventlog ? or there are other things ?
>

Jarkko, can you please also help me to understand here more ?

Thanks & Regards,
   - Nayna

>>
>> If the event_log pointer is NULL, then event log is not supported.
>
> Yeah, sure will fix this.
>
> Thanks & Regards,
>       - Nayna
>>
>> /Jarkko
>>
>
>
> ------------------------------------------------------------------------------
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> _______________________________________________
> tpmdd-devel mailing list
> [e-mail]
> https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
>


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Jarkko Sakkinen Oct. 9, 2016, 12:05 p.m. UTC | #4

On Sun, Oct 09, 2016 at 04:59:15PM +0530, Nayna wrote:
> 
> 
> On 10/07/2016 02:08 AM, Nayna wrote:
> >
> >
> >On 10/01/2016 12:35 AM, Jarkko Sakkinen wrote:
> >>On Wed, Sep 28, 2016 at 04:34:38AM -0400, Nayna Jain wrote:
> >>>Currently, read_log() has two implementations: one for ACPI platforms
> >>>and the other for OF platforms. The proper one is selected at compile
> >>>time using Kconfig and #ifdef in the Makefile, which is not the
> >>>recommended approach.
> >>>
> >>>This patch removes the #ifdef in the Makefile by defining a single
> >>>read_log() method, which checks for ACPI/OF event log properties at
> >>>runtime.
> >>>
> >>>Suggested-by: Jason Gunthorpe <[e-mail]>
> >>>Signed-off-by: Nayna Jain <[e-mail]>
> >>>Reviewed-by: Jason Gunthorpe <[e-mail]>
> >>>---
> >>>   drivers/char/tpm/Makefile       | 14 ++++----------
> >>>   drivers/char/tpm/tpm_acpi.c     |  9 ++-------
> >>>   drivers/char/tpm/tpm_eventlog.c | 18 ++++++++++++++++++
> >>>   drivers/char/tpm/tpm_eventlog.h | 22 +++++++++++++---------
> >>>   drivers/char/tpm/tpm_of.c       |  8 ++------
> >>>   5 files changed, 39 insertions(+), 32 deletions(-)
> >>>
> >>>diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
> >>>index a385fb8..a05b1eb 100644
> >>>--- a/drivers/char/tpm/Makefile
> >>>+++ b/drivers/char/tpm/Makefile
> >>>@@ -2,16 +2,10 @@
> >>>   # Makefile for the kernel tpm device drivers.
> >>>   #
> >>>   obj-$(CONFIG_TCG_TPM) += tpm.o
> >>>-tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
> >>>-tpm-$(CONFIG_ACPI) += tpm_ppi.o
> >>>-
> >>>-ifdef CONFIG_ACPI
> >>>-	tpm-y += tpm_eventlog.o tpm_acpi.o
> >>>-else
> >>>-ifdef CONFIG_TCG_IBMVTPM
> >>>-	tpm-y += tpm_eventlog.o tpm_of.o
> >>>-endif
> >>>-endif
> >>>+tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
> >>>+		tpm_eventlog.o
> >>>+tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
> >>>+tpm-$(CONFIG_OF) += tpm_of.o
> >>>   obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
> >>>   obj-$(CONFIG_TCG_TIS) += tpm_tis.o
> >>>   obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
> >>>diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
> >>>index 4d6c2d7..859bdba 100644
> >>>--- a/drivers/char/tpm/tpm_acpi.c
> >>>+++ b/drivers/char/tpm/tpm_acpi.c
> >>>@@ -6,6 +6,7 @@
> >>>    *	Stefan Berger <[e-mail]>
> >>>    *	Reiner Sailer <[e-mail]>
> >>>    *	Kylene Hall <[e-mail]>
> >>>+ *	Nayna Jain <[e-mail]>
> >>>    *
> >>>    * Maintained by: <[e-mail]>
> >>>    *
> >>>@@ -45,7 +46,7 @@ struct acpi_tcpa {
> >>>   };
> >>>
> >>>   /* read binary bios log */
> >>>-int read_log(struct tpm_chip *chip)
> >>>+int read_log_acpi(struct tpm_chip *chip)
> >>>   {
> >>>   	struct acpi_tcpa *buff;
> >>>   	acpi_status status;
> >>>@@ -54,12 +55,6 @@ int read_log(struct tpm_chip *chip)
> >>>   	struct tpm_bios_log *log;
> >>>
> >>>   	log = &chip->log;
> >>>-	if (log->bios_event_log != NULL) {
> >>>-		printk(KERN_ERR
> >>>-		       "%s: ERROR - Eventlog already initialized\n",
> >>>-		       __func__);
> >>>-		return -EFAULT;
> >>>-	}
> >>>
> >>>   	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
> >>>   	status = acpi_get_table(ACPI_SIG_TCPA, 1,
> >>>diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
> >>>index a8cd4a1..c327089 100644
> >>>--- a/drivers/char/tpm/tpm_eventlog.c
> >>>+++ b/drivers/char/tpm/tpm_eventlog.c
> >>>@@ -346,6 +346,24 @@ static int is_bad(void *p)
> >>>   	return 0;
> >>>   }
> >>>
> >>>+int read_log(struct tpm_chip *chip)
> >>>+{
> >>>+	int rc;
> >>>+
> >>>+	if (chip->log.bios_event_log != NULL) {
> >>>+		dev_dbg(&chip->dev, "%s: ERROR - Eventlog already initialized\n",
> >>>+			__func__);
> >>>+		return -EFAULT;
> >>>+	}
> >>>+
> >>>+	rc = read_log_acpi(chip);
> >>>+	if ((rc == 0) || (rc == -ENOMEM))
> >>>+		return rc;
> >>>+	rc = read_log_of(chip);
> >>>+	return rc;
> >>>+
> >>>+}
> >>
> >>I'm wondering if it is a better idea to leverage tpm_class_ops? This
> >>would be kind of cool idea to implement this because then the decision
> >>to support event log could be leveraged to the driver level.
> >
> >Can you please explain me this bit more ?
> >
> >For eg, when we say driver level.. does that mean to the level of tis,
> >nuvoton ?
> >
> >And what type of decision ? I mean like decision to create securityfs
> >setup for userspace to read eventlog ? or there are other things ?
> >
> 
> Jarkko, can you please also help me to understand here more ?

Sorry, I missed your original response.

Umh, it was more like an open question and I'm not sure if it even
makes sense. Maybe you can just ignore it until the next revision.

/Jarkko

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Jason Gunthorpe Oct. 10, 2016, 3:24 a.m. UTC | #5

On Sun, Oct 09, 2016 at 03:05:53PM +0300, Jarkko Sakkinen wrote:

> > Jarkko, can you please also help me to understand here more ?
> 
> Sorry, I missed your original response.
> 
> Umh, it was more like an open question and I'm not sure if it even
> makes sense. Maybe you can just ignore it until the next revision.

For now we two standard ways to find the log that do not require
intervention of the low level driver, so I'd leave it as is until
something changes.

Jason

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Patch

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index a385fb8..a05b1eb 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -2,16 +2,10 @@ 
 # Makefile for the kernel tpm device drivers.
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
-tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
-tpm-$(CONFIG_ACPI) += tpm_ppi.o
-
-ifdef CONFIG_ACPI
-	tpm-y += tpm_eventlog.o tpm_acpi.o
-else
-ifdef CONFIG_TCG_IBMVTPM
-	tpm-y += tpm_eventlog.o tpm_of.o
-endif
-endif
+tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \
+		tpm_eventlog.o
+tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_acpi.o
+tpm-$(CONFIG_OF) += tpm_of.o
 obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
 obj-$(CONFIG_TCG_TIS) += tpm_tis.o
 obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
index 4d6c2d7..859bdba 100644
--- a/drivers/char/tpm/tpm_acpi.c
+++ b/drivers/char/tpm/tpm_acpi.c
@@ -6,6 +6,7 @@ 
  *	Stefan Berger <[e-mail]>
  *	Reiner Sailer <[e-mail]>
  *	Kylene Hall <[e-mail]>
+ *	Nayna Jain <[e-mail]>
  *
  * Maintained by: <[e-mail]>
  *
@@ -45,7 +46,7 @@  struct acpi_tcpa {
 };
 
 /* read binary bios log */
-int read_log(struct tpm_chip *chip)
+int read_log_acpi(struct tpm_chip *chip)
 {
 	struct acpi_tcpa *buff;
 	acpi_status status;
@@ -54,12 +55,6 @@  int read_log(struct tpm_chip *chip)
 	struct tpm_bios_log *log;
 
 	log = &chip->log;
-	if (log->bios_event_log != NULL) {
-		printk(KERN_ERR
-		       "%s: ERROR - Eventlog already initialized\n",
-		       __func__);
-		return -EFAULT;
-	}
 
 	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
 	status = acpi_get_table(ACPI_SIG_TCPA, 1,
diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
index a8cd4a1..c327089 100644
--- a/drivers/char/tpm/tpm_eventlog.c
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -346,6 +346,24 @@  static int is_bad(void *p)
 	return 0;
 }
 
+int read_log(struct tpm_chip *chip)
+{
+	int rc;
+
+	if (chip->log.bios_event_log != NULL) {
+		dev_dbg(&chip->dev, "%s: ERROR - Eventlog already initialized\n",
+			__func__);
+		return -EFAULT;
+	}
+
+	rc = read_log_acpi(chip);
+	if ((rc == 0) || (rc == -ENOMEM))
+		return rc;
+	rc = read_log_of(chip);
+	return rc;
+
+}
+
 int tpm_bios_log_setup(struct tpm_chip *chip)
 {
 	const char *name = dev_name(&chip->dev);
diff --git a/drivers/char/tpm/tpm_eventlog.h b/drivers/char/tpm/tpm_eventlog.h
index 7ea066c..9e95b7e 100644
--- a/drivers/char/tpm/tpm_eventlog.h
+++ b/drivers/char/tpm/tpm_eventlog.h
@@ -78,20 +78,24 @@  enum tcpa_pc_event_ids {
 	HOST_TABLE_OF_DEVICES,
 };
 
-int read_log(struct tpm_chip *chip);
-
-#if defined(CONFIG_TCG_IBMVTPM) || defined(CONFIG_TCG_IBMVTPM_MODULE) || \
-	defined(CONFIG_ACPI)
-extern int tpm_bios_log_setup(struct tpm_chip *chip);
-extern void tpm_bios_log_teardown(struct tpm_chip *chip);
+#if defined(CONFIG_ACPI)
+int read_log_acpi(struct tpm_chip *chip);
 #else
-static inline int tpm_bios_log_setup(struct tpm_chip *chip)
+static inline int read_log_acpi(struct tpm_chip *chip)
 {
-	return 0;
+	return -ENODEV;
 }
-static inline void tpm_bios_log_teardown(struct tpm_chip *chip)
+#endif
+#if defined(CONFIG_OF)
+int read_log_of(struct tpm_chip *chip);
+#else
+static inline int read_log_of(struct tpm_chip *chip)
 {
+	return -ENODEV;
 }
 #endif
 
+int tpm_bios_log_setup(struct tpm_chip *chip);
+void tpm_bios_log_teardown(struct tpm_chip *chip);
+
 #endif
diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
index 68d891a..7c30752 100644
--- a/drivers/char/tpm/tpm_of.c
+++ b/drivers/char/tpm/tpm_of.c
@@ -2,6 +2,7 @@ 
  * Copyright 2012 IBM Corporation
  *
  * Author: Ashley Lai <[e-mail]>
+ *         Nayna Jain <[e-mail]>
  *
  * Maintained by: <[e-mail]>
  *
@@ -20,7 +21,7 @@ 
 #include "tpm.h"
 #include "tpm_eventlog.h"
 
-int read_log(struct tpm_chip *chip)
+int read_log_of(struct tpm_chip *chip)
 {
 	struct device_node *np;
 	const u32 *sizep;
@@ -28,11 +29,6 @@  int read_log(struct tpm_chip *chip)
 	struct tpm_bios_log *log;
 
 	log = &chip->log;
-	if (log->bios_event_log != NULL) {
-		pr_err("%s: ERROR - Eventlog already initialized\n", __func__);
-		return -EFAULT;
-	}
-
 	np = of_find_node_by_name(NULL, "vtpm");
 	if (!np) {
 		pr_err("%s: ERROR - IBMVTPM not supported\n", __func__);