drm/i915: Allow switching away via vga-switcheroo if uninitialized

Always allow switching away via vga-switcheroo if the display is
uninitalized. Instead prevent switching to i915 if the device has
not been initialized.

This issue was introduced by commit 5df7bd130818 ("drm/i915: skip
display initialization when there is no display") protected, which
protects code paths from being executed on uninitialized devices.
In the case of vga-switcheroo, we want to allow a switch away from
i915's device. So run vga_switcheroo_process_delayed_switch() and
test in the switcheroo callbacks if the i915 device is available.

Fixes: 5df7bd130818 ("drm/i915: skip display initialization when there is no display")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: "Jouni Högander" <jouni.hogander@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: "José Roberto de Souza" <jose.souza@intel.com>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Cc: intel-gfx@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.14+
Link: https://patchwork.freedesktop.org/patch/msgid/20230116115425.13484-2-tzimmermann@suse.de

drm/i915/driver: add i915_driver_ prefix to functions

Add the i915_driver_ prefix to the switcheroo functions in
i915_driver.[ch].

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211111101304.13094-3-jani.nikula@intel.com

drm/i915/driver: rename i915_drv.c to i915_driver.c

This is more about trimming i915_drv.h than the renamed
i915_driver.[ch]. Split out i915_driver.[ch] out of i915_drv.h as a
feasible thing to do.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211111101304.13094-1-jani.nikula@intel.com

drm/i915: Remove references to struct drm_device.pdev

Using struct drm_device.pdev is deprecated. Convert i915 to struct
drm_device.dev. No functional changes.

v6:
* also remove assignment in selftests/ in a later patch (Chris)
v5:
* remove assignment in later patch (Chris)
v3:
* rebased
v2:
* move gt/ and gvt/ changes into separate patches

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210128133127.2311-2-tzimmermann@suse.de

drm/i915/switcheroo: use struct drm_device based logging

Convert all the pr_* logging macros to the struct drm_device based
macros to provide device specific logging.

No functional changes.

Cc: Wambui Karuga <wambui.karugax@gmail.com>
Reviewed-by: Wambui Karuga <wambui.karugax@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200402114819.17232-9-jani.nikula@intel.com

drm: Avoid drm_global_mutex for simple inc/dec of dev->open_count

Since drm_global_mutex is a true global mutex across devices, we don't
want to acquire it unless absolutely necessary. For maintaining the
device local open_count, we can use atomic operations on the counter
itself, except when making the transition to/from 0. Here, we tackle the
easy portion of delaying acquiring the drm_global_mutex for the final
release by using atomic_dec_and_mutex_lock(), leaving the global
serialisation across the device opens.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Thomas Hellström (VMware) <thomas_os@shipmail.org>
Reviewed-by: Thomas Hellström <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200124130107.125404-1-chris@chris-wilson.co.uk

drm/i915: split out i915_switcheroo.[ch] from i915_drv.c

Split out code related to vga switcheroo register/unregister and state
handling from i915_drv.c into new i915_switcheroo.[ch] files.

It's a bit difficult to draw the line how much to move to the new file
from i915_drv.c, but it seemed to me keeping i915_suspend_switcheroo()
and i915_resume_switcheroo() in place was the cleanest.

No functional changes.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004122019.12009-2-jani.nikula@intel.com