linux-imx

ice: fix issue where host reboots on unload when iommu=on

Currently if the kernel has the intel_iommu=on parameter set, on some
platforms removing the driver causes a system reboot. In initialization
we associate the control queue interrupts with the pf->hw_oicr_idx and
enable the interrupts by setting the CAUSE_ENA bit. The problem comes
on teardown because we are not clearing the CAUSE_ENA bit for the
control queues, but the vector at pf->hw_oicr_idx (miscellaneous
interrupt vector) gets disabled.

Fix this by clearing the CAUSE_ENA bit in the appropriate control queue
registers on when freeing the miscellaneous interrupt vector. Also,
move the call to ice_free_irq_msix_misc() to after ice_deinit_sw() in
ice_remove() because ice_deinit_sw() makes an AQ call, but
ice_free_irq_msix_misc() disables the miscellaneous vector and it's
associated interrupts.

Also, create two small helper functions to enable and disable the
control queue interrupts respectively.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>