On 2020-06-23 22:55, Mathieu Poirier wrote:
On Tue, Jun 16, 2020 at 10:26:23AM +0530, Sai Prakash Ranjan wrote:
Implement a shutdown callback to ensure ETR hardware is properly shutdown in reboot/shutdown path. This is required for ETR which has SMMU address translation enabled like on SC7180 SoC and few others. If the hardware is still accessing memory after SMMU translation is disabled as part of SMMU shutdown callback in system reboot or shutdown path, then IOVAs(I/O virtual address) which it was using will go on the bus as the physical addresses which might result in unknown crashes (NoC/interconnect errors). So we make sure from this shutdown callback that the ETR is shutdown before SMMU translation is disabled and device_link in SMMU driver will take care of ordering of shutdown callbacks such that SMMU shutdown callback is not called before any of its consumer shutdown callbacks.
Signed-off-by: Sai Prakash Ranjan saiprakash.ranjan@codeaurora.org
I have applied your patch.
Thanks Mathieu.