[Intel-gfx] [v2] drm/i915/display: Add a wrapper function for vga decode setup

[Shankar, Uma]

> -----Original Message-----
> From: Nikula, Jani <jani.nikula at intel.com>
> Sent: Tuesday, September 26, 2023 4:26 PM
> To: Shankar, Uma <uma.shankar at intel.com>; intel-gfx at lists.freedesktop.org
> Cc: Shankar, Uma <uma.shankar at intel.com>
> Subject: Re: [v2] drm/i915/display: Add a wrapper function for vga decode setup
> 
> On Tue, 26 Sep 2023, Jani Nikula <jani.nikula at intel.com> wrote:
> > On Mon, 25 Sep 2023, Uma Shankar <uma.shankar at intel.com> wrote:
> >> Some of the VGA functionality is not needed by the proposed Intel Xe
> >> driver, while this will be utilized by i915.
> >> Adding a wrapper function for VGA decode setup.
> 
> I guess "wrapper function" is now a misnomer? There's no wrapping here?

Yeah, will re-phrase it.

Regards,
Uma Shankar

> >
> > So, this duplicates intel_vga_set_decode() without removing the old
> > one. Is that the intention?
> >
> > I guess the idea here is that xe doesn't build intel_gmch, so you can
> > add a nop version there?
> >
> > BR,
> > Jani.
> >
> >
> >
> >>
> >> v2: Addressed Jani Nikula's review comments.
> >>
> >> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/display/intel_vga.c |  2 --
> >>  drivers/gpu/drm/i915/soc/intel_gmch.c    | 14 ++++++++++++++
> >>  drivers/gpu/drm/i915/soc/intel_gmch.h    |  2 ++
> >>  3 files changed, 16 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/display/intel_vga.c
> >> b/drivers/gpu/drm/i915/display/intel_vga.c
> >> index 286a0bdd28c6..0f65ce115035 100644
> >> --- a/drivers/gpu/drm/i915/display/intel_vga.c
> >> +++ b/drivers/gpu/drm/i915/display/intel_vga.c
> >> @@ -3,11 +3,9 @@
> >>   * Copyright © 2019 Intel Corporation
> >>   */
> >>
> >> -#include <linux/pci.h>
> >>  #include <linux/vgaarb.h>
> >>
> >>  #include <video/vga.h>
> >> -
> >>  #include "soc/intel_gmch.h"
> >>
> >>  #include "i915_drv.h"
> >> diff --git a/drivers/gpu/drm/i915/soc/intel_gmch.c
> >> b/drivers/gpu/drm/i915/soc/intel_gmch.c
> >> index 49c7fb16e934..f32e9f78770a 100644
> >> --- a/drivers/gpu/drm/i915/soc/intel_gmch.c
> >> +++ b/drivers/gpu/drm/i915/soc/intel_gmch.c
> >> @@ -5,6 +5,7 @@
> >>
> >>  #include <linux/pci.h>
> >>  #include <linux/pnp.h>
> >> +#include <linux/vgaarb.h>
> >>
> >>  #include <drm/drm_managed.h>
> >>  #include <drm/i915_drm.h>
> >> @@ -167,3 +168,16 @@ int intel_gmch_vga_set_state(struct
> >> drm_i915_private *i915, bool enable_decode)
> >>
> >>  	return 0;
> >>  }
> >> +
> >> +unsigned int intel_gmch_vga_set_decode(struct pci_dev *pdev, bool
> >> +enable_decode) {
> >> +	struct drm_i915_private *i915 = pdev_to_i915(pdev);
> >> +
> >> +	intel_gmch_vga_set_state(i915, enable_decode);
> >> +
> >> +	if (enable_decode)
> >> +		return VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
> >> +		       VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
> >> +	else
> >> +		return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; }
> >> diff --git a/drivers/gpu/drm/i915/soc/intel_gmch.h
> >> b/drivers/gpu/drm/i915/soc/intel_gmch.h
> >> index d0133eedc720..23be2d113afd 100644
> >> --- a/drivers/gpu/drm/i915/soc/intel_gmch.h
> >> +++ b/drivers/gpu/drm/i915/soc/intel_gmch.h
> >> @@ -8,11 +8,13 @@
> >>
> >>  #include <linux/types.h>
> >>
> >> +struct pci_dev;
> >>  struct drm_i915_private;
> >>
> >>  int intel_gmch_bridge_setup(struct drm_i915_private *i915);  void
> >> intel_gmch_bar_setup(struct drm_i915_private *i915);  void
> >> intel_gmch_bar_teardown(struct drm_i915_private *i915);  int
> >> intel_gmch_vga_set_state(struct drm_i915_private *i915, bool
> >> enable_decode);
> >> +unsigned int intel_gmch_vga_set_decode(struct pci_dev *pdev, bool
> >> +enable_decode);
> >>
> >>  #endif /* __INTEL_GMCH_H__ */
> 
> --
> Jani Nikula, Intel