Re: [PATCH 10/19] drm/i915/de: Simplify intel_de_read8()

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 08 Dec 2025, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> intel_de_read8() is only needed for VGA register MMIO access
> by the CRT code on gen2/3. Remove the redundant wakelock stuff,
> and add a platform check to make sure this won't get used on
> any platform where MMIO VGA register accesses don't work.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Not a fan of adding the extra dep on drm_print.h as I've tried hard to
remove it from headers all over the place to uncover the implicit
dependencies.

Oh well, maybe this will be addressed in the upcoming mmio series?

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> ---
>  drivers/gpu/drm/i915/display/intel_de.h | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_de.h b/drivers/gpu/drm/i915/display/intel_de.h
> index a7ce3b875e06..5c1b37d30045 100644
> --- a/drivers/gpu/drm/i915/display/intel_de.h
> +++ b/drivers/gpu/drm/i915/display/intel_de.h
> @@ -6,6 +6,8 @@
>  #ifndef __INTEL_DE_H__
>  #define __INTEL_DE_H__
>  
> +#include <drm/drm_print.h>
> +
>  #include "intel_display_core.h"
>  #include "intel_dmc_wl.h"
>  #include "intel_dsb.h"
> @@ -34,15 +36,10 @@ intel_de_read(struct intel_display *display, i915_reg_t reg)
>  static inline u8
>  intel_de_read8(struct intel_display *display, i915_reg_t reg)
>  {
> -	u8 val;
> +	/* this is only used on VGA registers (possible on pre-g4x) */
> +	drm_WARN_ON(display->drm, DISPLAY_VER(display) >= 5 || display->platform.g4x);
>  
> -	intel_dmc_wl_get(display, reg);
> -
> -	val = intel_uncore_read8(__to_uncore(display), reg);
> -
> -	intel_dmc_wl_put(display, reg);
> -
> -	return val;
> +	return intel_uncore_read8(__to_uncore(display), reg);
>  }
>  
>  static inline u64

-- 
Jani Nikula, Intel