iommu/rockchip: Clear stale page faults before enabling stall

Boot firmware can leave an IOMMU bank in PAGE_FAULT_ACTIVE before the
driver has configured paging:

  PAGE_FAULT_ACTIVE=1  STALL_ACTIVE=0  IDLE=1

Such a bank ignores CMD_ENABLE_STALL and never reaches STALL_ACTIVE, so
rk_iommu_enable_stall()'s readx_poll_timeout() spins until it times out
(seen on the RK3576 NPU, whose MMUs share this poll across banks).

Rather than special-casing these banks in the stall path, acknowledge the
stale fault with CMD_PAGE_FAULT_DONE before enabling stall, so every bank
starts from a clean state and the normal stall sequence applies to all of
them.  Banks without a pending fault are untouched.

Signed-off-by: Jiaxing Hu <gahing@gahingwoo.com>
Signed-off-by: Will Deacon <will@kernel.org>

0 files changed, 0 insertions, 0 deletions