drm/nouveau/bar: switch to instanced constructor

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drm/nouveau/bar: modify interface to bar2 vmm mapping

Match API with the BAR1 version.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: modify interface to bar1 vmm mapping

Upcoming changes will remove the nvkm_vmm pointer from nvkm_vma, instead
requiring it to be explicitly specified on each operation.

It's not currently possible to get this information for BAR1 mappings,
so let's fix that ahead of time.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: expose interface to bar2 teardown

Will prevent spurious MMU fault interrupts if something decides to touch
BAR1 after we've unloaded the driver.

Exposed external to BAR so that INSTMEM can use it to better control the
suspend/resume fast-path access.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: expose interface to bar2 initialisation

If we want to be able to hit the instmem fast-path in a few trickier cases,
we need to be more flexible with when we can initialise BAR2 access.

There's probably a decent case to be made for merging BAR/INSTMEM into BUS,
but that's something to ponder another day.

Flushes have been added after the write to bind the instance block,
as later commits will reveal the need for them.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: implement bar1 teardown

Will prevent spurious MMU fault interrupts if something decides to touch
BAR1 after we've unloaded the driver.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: move bar1 initialisation into its own function

BAR2 being done for practical reasons, this is just for consistency.

Flushes have been added after the write to bind the instance block,
as later commits will reveal the need for them.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/bar: convert to new-style nvkm_subdev

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>