[Intel-gfx] [PATCH 16/16] drm/i915: make device info a pointer to static const data

[Maarten Lankhorst]

Op 20-06-2022 om 10:49 schreef Jani Nikula:
> Now that the device info is no longer modified runtime, we don't need to
> make a copy of it, and we can convert i915->__info into a pointer to
> static const data. Also remove mkwrite_device_info().
>
> This does increase the text size slightly.
>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
>
> ---
>
> An alternative is to keep copying device info, but casting away the
> const only once at the copy time, removing mkwrite_device_info().
> ---
>  drivers/gpu/drm/i915/i915_driver.c |  8 ++------
>  drivers/gpu/drm/i915/i915_drv.h    | 11 ++---------
>  2 files changed, 4 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
> index 5969cc7805d3..9c9c492e97a8 100644
> --- a/drivers/gpu/drm/i915/i915_driver.c
> +++ b/drivers/gpu/drm/i915/i915_driver.c
> @@ -793,9 +793,6 @@ static void i915_welcome_messages(struct drm_i915_private *dev_priv)
>  static struct drm_i915_private *
>  i915_driver_create(struct pci_dev *pdev, const struct pci_device_id *ent)
>  {
> -	const struct intel_device_info *match_info =
> -		(struct intel_device_info *)ent->driver_data;
> -	struct intel_device_info *device_info;
>  	struct intel_runtime_info *runtime;
>  	struct drm_i915_private *i915;
>  
> @@ -809,9 +806,8 @@ i915_driver_create(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	/* Device parameters start as a copy of module parameters. */
>  	i915_params_copy(&i915->params, &i915_modparams);
>  
> -	/* Setup the write-once "constant" device info */
> -	device_info = mkwrite_device_info(i915);
> -	memcpy(device_info, match_info, sizeof(*device_info));
> +	/* Static const device info. */
> +	i915->__info = (const struct intel_device_info *)ent->driver_data;
>  
>  	/* Initialize initial runtime info from static const data and pdev. */
>  	runtime = RUNTIME_INFO(i915);
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 89472440947c..a2a57f07c5be 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -380,7 +380,7 @@ struct drm_i915_private {
>  	/* i915 device parameters */
>  	struct i915_params params;
>  
> -	const struct intel_device_info __info; /* Use INTEL_INFO() to access. */
> +	const struct intel_device_info *__info; /* Use INTEL_INFO() to access. */
>  	struct intel_runtime_info __runtime; /* Use RUNTIME_INFO() to access. */
>  	struct intel_driver_caps caps;
>  
> @@ -848,7 +848,7 @@ static inline struct intel_gt *to_gt(struct drm_i915_private *i915)
>  	GENMASK(INTEL_FRONTBUFFER_BITS_PER_PIPE * ((pipe) + 1) - 1, \
>  		INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe))
>  
> -#define INTEL_INFO(dev_priv)	(&(dev_priv)->__info)
> +#define INTEL_INFO(__i915)	(__i915->__info)
>  #define RUNTIME_INFO(dev_priv)	(&(dev_priv)->__runtime)
>  #define DRIVER_CAPS(dev_priv)	(&(dev_priv)->caps)
>  
> @@ -1432,13 +1432,6 @@ void i915_gem_driver_release(struct drm_i915_private *dev_priv);
>  
>  int i915_gem_open(struct drm_i915_private *i915, struct drm_file *file);
>  
> -/* intel_device_info.c */
> -static inline struct intel_device_info *
> -mkwrite_device_info(struct drm_i915_private *dev_priv)
> -{
> -	return (struct intel_device_info *)INTEL_INFO(dev_priv);
> -}
> -
>  static inline enum i915_map_type
>  i915_coherent_map_type(struct drm_i915_private *i915,
>  		       struct drm_i915_gem_object *obj, bool always_coherent)

I think just moving around things is safest in this case. I believe all should be moved to the new display sub-struct, but this is a start of making that easier.

For the series, except patch 5:

Reviewed-by: Maarten Lankhort <maarten.lankhorst at linux.intel.com>