The qxl device supports only a single active framebuffer ("primary
surface" in spice terminology). In multihead configurations are handled
by defining rectangles within the primary surface for each head/crtc.
Userspace which uses the qxl ioctl interface (xorg qxl driver) is aware
of this limitation and will setup framebuffers and crtcs accordingly.
Userspace which uses dumb framebuffers (xorg modesetting driver,
wayland) is not aware of this limitation and tries to use two
framebuffers (one for each crtc) instead.
The qxl kms driver already has the dumb bo separated from the primary
surface, by using a (shared) shadow bo as primary surface. This is
needed to support pageflips without having to re-create the primary
surface. The qxl driver will blit from the dumb bo to the shadow bo
instead.
So we can extend the shadow logic: Maintain a global shadow bo (aka
primary surface), make it big enough that dumb bo's for all crtcs fit in
side-by-side. Adjust the pageflip blits to place the heads next to each
other in the shadow.
With this patch in place multihead qxl works with wayland.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20190118122020.27596-15-kraxel@redhat.com
Lots of code can be removed by relying on fb-helper:
- "struct drm_framebuffer" moves to fb_helper.fb.
- "struct drm_gem_object" moves to fb_helper.obj[0].
- "struct qxl_device" can be inferred as drm_fb_helper is embedded.
- qxl_user_framebuffer_create -> drm_gem_fb_create.
- qxl_user_framebuffer_destroy -> drm_gem_fb_destroy.
- qxl_fbdev_destroy -> drm_fb_helper_fbdev_teardown + vfree(shadow).
Remove unused code:
- qxl_fbdev_qobj_is_fb, qxl_fbdev_set_suspend.
- Unused fields of qxl_fbdev: delayed_ops, delayed_ops_lock, size.
Misc notes:
- The dirty callback is preserved as it is necessary to trigger update
commands in the hw (the screen stays black otherwise).
- No idea when .create_handle in drm_framebuffer_funcs is used, but use
the same drm_gem_fb_create_handle to match drm_gem_fb_funcs.
- I don't know why qxl_fb_find_or_create_single used to check for an
existing framebuffer and removed that check to match other drivers.
- Use of drm_fb_helper_fbdev_teardown also requires "info->fbdefio" to
be dynamically allocated. Replace the existing defio config by
drm_fb_helper_defio_init to accomodate this.
Testing results: startx with fbdev, modesetting and qxl all seems to
work. Tested also with CONFIG_DRM_FBDEV_EMULATION=n, fbdev obviously
fails but others are fine. QEMU -spice and QEMU -spice with vdagent and
multiple (resized) displays (via remote-viewer) also works.
unbind vtconsole and rmmod has *not* regressed (i.e. it still trips on a
use-after-free in qxl_check_idle via qxl_ttm_fini).
Ideally setup/teardown is replaced by drm_fbdev_generic_setup as that
would result in further code reduction, improve error handling (like not
leaking shadow memory), but unfortunately QXL has no implementation for
qxl_gem_prime_vmap.
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Link: http://patchwork.freedesktop.org/patch/msgid/20180910132156.23201-1-peter@lekensteyn.nl
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
GCC doesn't complain about this but my static checker does. We're
passing "drawable" before initializing it. It's not actually used so
it's harmless and I just removed it.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160711084716.GB31411@mwanda
The recent addition of lockdep support to reservations and their subsequent
use by TTM showed up a number of potential problems with the way qxl was using
TTM objects.
a) it was allocating objects, and reserving them later without validating
underneath the reservation, which meant in extreme conditions the objects could
be evicted before the reservation ever used them.
b) it was reserving objects straight after allocating them, but with no
ability to back off should the reservations fail. It now allocates the necessary
objects then does a complete reservation pass on them to avoid deadlocks.
c) it had two lists per release tracking objects, unnecessary complicating
the reservation process.
This patch removes the dual object tracking, adds reservations ticket support
to the release and fence object handling. It then ports the internal fb
drawing code and the userspace facing ioctl to use the new interfaces properly,
along with cleanup up the error path handling in some codepaths.
Signed-off-by: Dave Airlie <airlied@redhat.com>
QXL is a paravirtual graphics device used by the Spice virtual desktop
interface.
The drivers uses GEM and TTM to manage memory, the qxl hw fencing however
is quite different than normal TTM expects, we have to keep track of a number
of non-linear fence ids per bo that we need to have released by the hardware.
The releases are freed from a workqueue that wakes up and processes the
release ring.
releases are suballocated from a BO, there are 3 release categories, drawables,
surfaces and cursor cmds. The hw also has 3 rings for commands, cursor and release handling.
The hardware also have a surface id tracking mechnaism and the driver encapsulates it completely inside the kernel, userspace never sees the actual hw surface
ids.
This requires a newer version of the QXL userspace driver, so shouldn't be
enabled until that has been placed into your distro of choice.
Authors: Dave Airlie, Alon Levy
v1.1: fixup some issues in the ioctl interface with padding
v1.2: add module device table
v1.3: fix nomodeset, fbcon leak, dumb bo create, release ring irq,
don't try flush release ring (broken hw), fix -modesetting.
v1.4: fbcon cpu usage reduction + suitable accel flags.
Signed-off-by: Alon Levy <alevy@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
