Re: [Intel-gfx] [PATCH 03/16] drm/i915: add initial runtime info into device info

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Mon, Jun 20, 2022 at 11:38:02AM +0300, Jani Nikula wrote:
> Add initial runtime info that we can copy to runtime info at i915
> creation time. This lets us define the initial values for runtime info
> statically while making it possible to change them runtime. This will be
> the new home for the current "const" device info members that are
> modified runtime anyway.
> 
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_driver.c       |  7 +++-
>  drivers/gpu/drm/i915/intel_device_info.h | 41 +++++++++++++-----------
>  2 files changed, 29 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
> index 0b00a05f1a74..5969cc7805d3 100644
> --- a/drivers/gpu/drm/i915/i915_driver.c
> +++ b/drivers/gpu/drm/i915/i915_driver.c
> @@ -796,6 +796,7 @@ 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;
>  
>  	i915 = devm_drm_dev_alloc(&pdev->dev, &i915_drm_driver,
> @@ -811,7 +812,11 @@ i915_driver_create(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	/* Setup the write-once "constant" device info */
>  	device_info = mkwrite_device_info(i915);
>  	memcpy(device_info, match_info, sizeof(*device_info));
> -	RUNTIME_INFO(i915)->device_id = pdev->device;
> +
> +	/* Initialize initial runtime info from static const data and pdev. */
> +	runtime = RUNTIME_INFO(i915);
> +	memcpy(runtime, &INTEL_INFO(i915)->__runtime, sizeof(*runtime));
> +	runtime->device_id = pdev->device;
>  
>  	return i915;
>  }
> diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
> index b86f68866e35..85385c98b9f4 100644
> --- a/drivers/gpu/drm/i915/intel_device_info.h
> +++ b/drivers/gpu/drm/i915/intel_device_info.h
> @@ -197,6 +197,27 @@ struct ip_version {
>  	u8 rel;
>  };
>  
> +struct intel_runtime_info {
> +	/*
> +	 * Platform mask is used for optimizing or-ed IS_PLATFORM calls into
> +	 * into single runtime conditionals, and also to provide groundwork
> +	 * for future per platform, or per SKU build optimizations.
> +	 *
> +	 * Array can be extended when necessary if the corresponding
> +	 * BUILD_BUG_ON is hit.
> +	 */
> +	u32 platform_mask[2];
> +
> +	u16 device_id;
> +
> +	u8 num_sprites[I915_MAX_PIPES];
> +	u8 num_scalers[I915_MAX_PIPES];

I was just thinking about moving these out from runtime init,
and perhaps converting to something a bit less funky (eg. plane
bitmask or somesuch thing). But then I got lost trying to parse
my way through the macro hell in i915_pci.c...

> +
> +	u32 rawclk_freq;
> +
> +	struct intel_step_info step;
> +};
> +
>  struct intel_device_info {
>  	struct ip_version graphics;
>  	struct ip_version media;
> @@ -252,27 +273,11 @@ struct intel_device_info {
>  		u32 degamma_lut_tests;
>  		u32 gamma_lut_tests;
>  	} color;
> -};
>  
> -struct intel_runtime_info {
>  	/*
> -	 * Platform mask is used for optimizing or-ed IS_PLATFORM calls into
> -	 * into single runtime conditionals, and also to provide groundwork
> -	 * for future per platform, or per SKU build optimizations.
> -	 *
> -	 * Array can be extended when necessary if the corresponding
> -	 * BUILD_BUG_ON is hit.
> +	 * Initial runtime info. Do not access outside of i915_driver_create().
>  	 */
> -	u32 platform_mask[2];
> -
> -	u16 device_id;
> -
> -	u8 num_sprites[I915_MAX_PIPES];
> -	u8 num_scalers[I915_MAX_PIPES];
> -
> -	u32 rawclk_freq;
> -
> -	struct intel_step_info step;
> +	const struct intel_runtime_info __runtime;
>  };
>  
>  struct intel_driver_caps {
> -- 
> 2.30.2

-- 
Ville Syrjälä
Intel