ACPI/IORT: Do not blindly trust DMA masks from firmware

mainline inclusion
from mainline-v5.11-rc6
commit a1df829e
category: bugfix
bugzilla: https://gitee.com/openeuler/qemu/issues/I4WE3Y


CVE: NA

--------------------------------

Address issue observed on real world system with suboptimal IORT table
where DMA masks of PCI devices would get set to 0 as result.

iort_dma_setup() would query the root complex'/named component IORT
entry for a DMA mask, and use that over the one the device has been
configured with earlier.

Ideally we want to use the minimum mask of what the IORT contains for
the root complex and what the device was configured with.

Fixes: 5ac65e8c ("ACPI/IORT: Support address size limit for root complexes")
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20210122012419.95010-1-mdf@kernel.org


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

 Conflicts:
	drivers/acpi/arm64/iort.c
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>