DRM drivers can use this to determine whether they can be enabled or not.
For now it's just a wrapper around drm_modeset_disabled() but having the
indirection level will allow to add other conditions besides "nomodeset".
Suggested-by: Thomas Zimmermann <[email protected]>
Signed-off-by: Javier Martinez Canillas <[email protected]>
---
drivers/gpu/drm/drm_drv.c | 21 +++++++++++++++++++++
include/drm/drm_drv.h | 1 +
2 files changed, 22 insertions(+)
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 8214a0b1ab7f..70ef08941e06 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -975,6 +975,27 @@ int drm_dev_set_unique(struct drm_device *dev, const char *name)
}
EXPORT_SYMBOL(drm_dev_set_unique);
+/**
+ * drm_drv_enabled - Checks if a DRM driver can be enabled
+ * @driver: DRM driver to check
+ *
+ * Checks whether a DRM driver can be enabled or not. This may be the case
+ * if the "nomodeset" kernel command line parameter is used.
+ *
+ * Returns:
+ * True if the DRM driver is enabled and false otherwise.
+ */
+bool drm_drv_enabled(const struct drm_driver *driver)
+{
+ if (drm_modeset_disabled()) {
+ DRM_INFO("%s driver is disabled\n", driver->name);
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(drm_drv_enabled);
+
/*
* DRM Core
* The DRM core module initializes all global DRM objects and makes them
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 0cd95953cdf5..48f2b6eec012 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -598,5 +598,6 @@ static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
int drm_dev_set_unique(struct drm_device *dev, const char *name);
+bool drm_drv_enabled(const struct drm_driver *driver);
#endif
--
2.33.1
On Wed, 03 Nov 2021, Javier Martinez Canillas <[email protected]> wrote:
> DRM drivers can use this to determine whether they can be enabled or not.
>
> For now it's just a wrapper around drm_modeset_disabled() but having the
> indirection level will allow to add other conditions besides "nomodeset".
>
> Suggested-by: Thomas Zimmermann <[email protected]>
> Signed-off-by: Javier Martinez Canillas <[email protected]>
Can't see i915 trivially using this due to the drm_driver
parameter. Please let's not merge helpers like this without actual
users.
BR,
Jani.
> ---
>
> drivers/gpu/drm/drm_drv.c | 21 +++++++++++++++++++++
> include/drm/drm_drv.h | 1 +
> 2 files changed, 22 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 8214a0b1ab7f..70ef08941e06 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -975,6 +975,27 @@ int drm_dev_set_unique(struct drm_device *dev, const char *name)
> }
> EXPORT_SYMBOL(drm_dev_set_unique);
>
> +/**
> + * drm_drv_enabled - Checks if a DRM driver can be enabled
> + * @driver: DRM driver to check
> + *
> + * Checks whether a DRM driver can be enabled or not. This may be the case
> + * if the "nomodeset" kernel command line parameter is used.
> + *
> + * Returns:
> + * True if the DRM driver is enabled and false otherwise.
> + */
> +bool drm_drv_enabled(const struct drm_driver *driver)
> +{
> + if (drm_modeset_disabled()) {
> + DRM_INFO("%s driver is disabled\n", driver->name);
> + return false;
> + }
> +
> + return true;
> +}
> +EXPORT_SYMBOL(drm_drv_enabled);
> +
> /*
> * DRM Core
> * The DRM core module initializes all global DRM objects and makes them
> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
> index 0cd95953cdf5..48f2b6eec012 100644
> --- a/include/drm/drm_drv.h
> +++ b/include/drm/drm_drv.h
> @@ -598,5 +598,6 @@ static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
>
> int drm_dev_set_unique(struct drm_device *dev, const char *name);
>
> +bool drm_drv_enabled(const struct drm_driver *driver);
>
> #endif
--
Jani Nikula, Intel Open Source Graphics Center
Hi
Am 03.11.21 um 14:41 schrieb Jani Nikula:
> On Wed, 03 Nov 2021, Javier Martinez Canillas <[email protected]> wrote:
>> DRM drivers can use this to determine whether they can be enabled or not.
>>
>> For now it's just a wrapper around drm_modeset_disabled() but having the
>> indirection level will allow to add other conditions besides "nomodeset".
>>
>> Suggested-by: Thomas Zimmermann <[email protected]>
>> Signed-off-by: Javier Martinez Canillas <[email protected]>
>
> Can't see i915 trivially using this due to the drm_driver
> parameter. Please let's not merge helpers like this without actual
> users.
Can you explain?
This would be called on the top of the PCI probe function. The parameter
would allow to decide on a per-driver base (e.g., to ignore generic
drivers).
Best regards
Thomas
>
> BR,
> Jani.
>
>
>> ---
>>
>> drivers/gpu/drm/drm_drv.c | 21 +++++++++++++++++++++
>> include/drm/drm_drv.h | 1 +
>> 2 files changed, 22 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
>> index 8214a0b1ab7f..70ef08941e06 100644
>> --- a/drivers/gpu/drm/drm_drv.c
>> +++ b/drivers/gpu/drm/drm_drv.c
>> @@ -975,6 +975,27 @@ int drm_dev_set_unique(struct drm_device *dev, const char *name)
>> }
>> EXPORT_SYMBOL(drm_dev_set_unique);
>>
>> +/**
>> + * drm_drv_enabled - Checks if a DRM driver can be enabled
>> + * @driver: DRM driver to check
>> + *
>> + * Checks whether a DRM driver can be enabled or not. This may be the case
>> + * if the "nomodeset" kernel command line parameter is used.
>> + *
>> + * Returns:
>> + * True if the DRM driver is enabled and false otherwise.
>> + */
>> +bool drm_drv_enabled(const struct drm_driver *driver)
>> +{
>> + if (drm_modeset_disabled()) {
>> + DRM_INFO("%s driver is disabled\n", driver->name);
>> + return false;
>> + }
>> +
>> + return true;
>> +}
>> +EXPORT_SYMBOL(drm_drv_enabled);
>> +
>> /*
>> * DRM Core
>> * The DRM core module initializes all global DRM objects and makes them
>> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
>> index 0cd95953cdf5..48f2b6eec012 100644
>> --- a/include/drm/drm_drv.h
>> +++ b/include/drm/drm_drv.h
>> @@ -598,5 +598,6 @@ static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
>>
>> int drm_dev_set_unique(struct drm_device *dev, const char *name);
>>
>> +bool drm_drv_enabled(const struct drm_driver *driver);
>>
>> #endif
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
On Wed, 03 Nov 2021, Thomas Zimmermann <[email protected]> wrote:
> Hi
>
> Am 03.11.21 um 14:41 schrieb Jani Nikula:
>> On Wed, 03 Nov 2021, Javier Martinez Canillas <[email protected]> wrote:
>>> DRM drivers can use this to determine whether they can be enabled or not.
>>>
>>> For now it's just a wrapper around drm_modeset_disabled() but having the
>>> indirection level will allow to add other conditions besides "nomodeset".
>>>
>>> Suggested-by: Thomas Zimmermann <[email protected]>
>>> Signed-off-by: Javier Martinez Canillas <[email protected]>
>>
>> Can't see i915 trivially using this due to the drm_driver
>> parameter. Please let's not merge helpers like this without actual
>> users.
>
> Can you explain?
>
> This would be called on the top of the PCI probe function. The parameter
> would allow to decide on a per-driver base (e.g., to ignore generic
> drivers).
Where and how exactly? This is why we need to see the patch using the
function. A patch is worth a thousand words. ;)
See current vgacon_text_force() usage in i915/i915_module.c. It happens
way before anything related to pci or drm driver. Why bother with the
complicated setup and teardown of stuff if you can bail out earlier?
BR,
Jani.
>
> Best regards
> Thomas
>
>>
>> BR,
>> Jani.
>>
>>
>>> ---
>>>
>>> drivers/gpu/drm/drm_drv.c | 21 +++++++++++++++++++++
>>> include/drm/drm_drv.h | 1 +
>>> 2 files changed, 22 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
>>> index 8214a0b1ab7f..70ef08941e06 100644
>>> --- a/drivers/gpu/drm/drm_drv.c
>>> +++ b/drivers/gpu/drm/drm_drv.c
>>> @@ -975,6 +975,27 @@ int drm_dev_set_unique(struct drm_device *dev, const char *name)
>>> }
>>> EXPORT_SYMBOL(drm_dev_set_unique);
>>>
>>> +/**
>>> + * drm_drv_enabled - Checks if a DRM driver can be enabled
>>> + * @driver: DRM driver to check
>>> + *
>>> + * Checks whether a DRM driver can be enabled or not. This may be the case
>>> + * if the "nomodeset" kernel command line parameter is used.
>>> + *
>>> + * Returns:
>>> + * True if the DRM driver is enabled and false otherwise.
>>> + */
>>> +bool drm_drv_enabled(const struct drm_driver *driver)
>>> +{
>>> + if (drm_modeset_disabled()) {
>>> + DRM_INFO("%s driver is disabled\n", driver->name);
>>> + return false;
>>> + }
>>> +
>>> + return true;
>>> +}
>>> +EXPORT_SYMBOL(drm_drv_enabled);
>>> +
>>> /*
>>> * DRM Core
>>> * The DRM core module initializes all global DRM objects and makes them
>>> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
>>> index 0cd95953cdf5..48f2b6eec012 100644
>>> --- a/include/drm/drm_drv.h
>>> +++ b/include/drm/drm_drv.h
>>> @@ -598,5 +598,6 @@ static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
>>>
>>> int drm_dev_set_unique(struct drm_device *dev, const char *name);
>>>
>>> +bool drm_drv_enabled(const struct drm_driver *driver);
>>>
>>> #endif
>>
--
Jani Nikula, Intel Open Source Graphics Center
Hello Jani,
On 11/4/21 12:10, Jani Nikula wrote:
> On Wed, 03 Nov 2021, Thomas Zimmermann <[email protected]> wrote:
>> Hi
>>
>> Am 03.11.21 um 14:41 schrieb Jani Nikula:
>>> On Wed, 03 Nov 2021, Javier Martinez Canillas <[email protected]> wrote:
>>>> DRM drivers can use this to determine whether they can be enabled or not.
>>>>
>>>> For now it's just a wrapper around drm_modeset_disabled() but having the
>>>> indirection level will allow to add other conditions besides "nomodeset".
>>>>
>>>> Suggested-by: Thomas Zimmermann <[email protected]>
>>>> Signed-off-by: Javier Martinez Canillas <[email protected]>
>>>
>>> Can't see i915 trivially using this due to the drm_driver
>>> parameter. Please let's not merge helpers like this without actual
>>> users.
>>
>> Can you explain?
>>
>> This would be called on the top of the PCI probe function. The parameter
>> would allow to decide on a per-driver base (e.g., to ignore generic
>> drivers).
>
> Where and how exactly? This is why we need to see the patch using the
> function. A patch is worth a thousand words. ;)
>
Thomas suggested to squash patches #4 and #5 so I'll do that when posting v2.
> See current vgacon_text_force() usage in i915/i915_module.c. It happens
> way before anything related to pci or drm driver. Why bother with the
> complicated setup and teardown of stuff if you can bail out earlier?
>
Yes, most drivers use vgacon_text_force() in their module init callback.
The ones that do in their probe function are drivers that don't have a
module init/exit but just use the module_platform_driver() macro.
I won't modify that and will keep the bail in the same place that the
drivers already do. I hope to have time and post a new revision today.
>
> BR,
> Jani.
>
Best regards,
--
Javier Martinez Canillas
Linux Engineering
Red Hat