drm/i915: Reinstate the mmap ioctl for some platforms

Reinstate the mmap ioctl for all current integrated platforms.
The intention was really to have it disabled for discrete graphics
where we enforce a single mmap mode.

This was reported to break ADL-P with the media stack, which was not the
intention. Although longer term we do still plan to sunset this ioctl
even for integrated, in favour of using mmap_offset instead.

Fixes: 35cbd91e ("drm/i915: Disable mmap ioctl for gen12+")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624112914.311984-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit d3f3baa3)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/gem/i915_gem_mman.c

@@ -61,10 +61,11 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	struct drm_i915_gem_object *obj;
 	unsigned long addr;
 
-	/* mmap ioctl is disallowed for all platforms after TGL-LP.  This also
-	 * covers all platforms with local memory.
+	/*
+	 * mmap ioctl is disallowed for all discrete platforms,
+	 * and for all platforms with GRAPHICS_VER > 12.
 	 */
-	if (GRAPHICS_VER(i915) >= 12 && !IS_TIGERLAKE(i915))
+	if (IS_DGFX(i915) || GRAPHICS_VER(i915) > 12)
 		return -EOPNOTSUPP;
 
 	if (args->flags & ~(I915_MMAP_WC))