SZ_16M PEM resource size includes PEM-specific register and its children resources. Reservation of the whole SZ_16M range leads to child device driver failure when pcieport driver is requesting resources: pcieport 0004:1f:00.0: can't enable device: BAR 0 [mem 0x87e0c0f00000-0x87e0c0ffffff 64bit] not claimed So we cannot reserve full 16M here and instead we want to reserve PEM-specific register only which is SZ_64K. At the end increase PEM resource to SZ_16M since this is what thunder_pem_init() call expects for proper initialization. Fixes: 9abb27c7594a ("PCI: thunder-pem: Add legacy firmware support for Cavium ThunderX host controller") Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx> CC: stable@xxxxxxxxxxxxxxx # v4.10+ --- drivers/pci/host/pci-thunder-pem.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/pci/host/pci-thunder-pem.c b/drivers/pci/host/pci-thunder-pem.c index b89c373..6e031b5 100644 --- a/drivers/pci/host/pci-thunder-pem.c +++ b/drivers/pci/host/pci-thunder-pem.c @@ -375,7 +375,6 @@ static void thunder_pem_legacy_fw(struct acpi_pci_root *root, index -= node * PEM_MAX_DOM_IN_NODE; res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) | FIELD_PREP(PEM_INDX_MASK, index); - res_pem->end = res_pem->start + SZ_16M - 1; res_pem->flags = IORESOURCE_MEM; } @@ -399,8 +398,15 @@ static int thunder_pem_acpi_init(struct pci_config_window *cfg) */ if (ret) { thunder_pem_legacy_fw(root, res_pem); - /* Reserve PEM-specific resources and PCI configuration space */ + /* + * Reserve 64K size PEM specific resources. The full 16M range + * size is required for thunder_pem_init() call. + */ + res_pem->end = res_pem->start + SZ_64K - 1; thunder_pem_reserve_range(dev, root->segment, res_pem); + res_pem->end = res_pem->start + SZ_16M - 1; + + /* Reserve PCI configuration space as well. */ thunder_pem_reserve_range(dev, root->segment, &cfg->res); } -- 2.7.4