PCI: xgene: Fix IB window setup

stable inclusion
from stable-v5.10.94
commit 6cbe8f8deb6286a33937b9b95204c6f77b232796
bugzilla: https://gitee.com/openeuler/kernel/issues/I531X9

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6cbe8f8deb6286a33937b9b95204c6f77b232796

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

commit c7a75d07 upstream.

Commit 6dce5aa5 ("PCI: xgene: Use inbound resources for setup")
broke PCI support on XGene. The cause is the IB resources are now sorted
in address order instead of being in DT dma-ranges order. The result is
which inbound registers are used for each region are swapped. I don't
know the details about this h/w, but it appears that IB region 0
registers can't handle a size greater than 4GB. In any case, limiting
the size for region 0 is enough to get back to the original assignment
of dma-ranges to regions.

Link: https://lore.kernel.org/all/CA+enf=v9rY_xnZML01oEgKLmvY1NGBUUhnSJaETmXtDtXfaczA@mail.gmail.com/
Link: https://lore.kernel.org/r/20211129173637.303201-1-robh@kernel.org
Fixes: 6dce5aa5 ("PCI: xgene: Use inbound resources for setup")
Reported-by: NStéphane Graber <stgraber@ubuntu.com>
Tested-by: NStéphane Graber <stgraber@ubuntu.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NKrzysztof Wilczyński <kw@linux.com>
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/pci/controller/pci-xgene.c

@@ -467,7 +467,7 @@ static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
 		return 1;
 	}
 
-	if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
+	if ((size > SZ_1K) && (size < SZ_4G) && !(*ib_reg_mask & (1 << 0))) {
 		*ib_reg_mask |= (1 << 0);
 		return 0;
 	}