From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
[ Upstream commit 08b1c19606b5fc7f895dae4d43d507b4da4a83bf ]
The static MCFG table tells us the base of ECAM space, but it does not
reserve the space -- the reservation should be done via a device in the
ACPI namespace whose _CRS includes the ECAM region.
Use acpi_resource_consumer() to check whether the ECAM space is reserved by
an ACPI namespace device. If it is, emit a message showing which device
reserves it. If not, emit a "[Firmware Bug]" warning.
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
arch/arm64/kernel/pci.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 409abc4..ac4509d 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -124,8 +124,9 @@ pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root)
struct device *dev = &root->device->dev;
struct resource *bus_res = &root->secondary;
u16 seg = root->segment;
- struct pci_config_window *cfg;
struct resource cfgres;
+ struct acpi_device *adev;
+ struct pci_config_window *cfg;
unsigned int bsz;
/* Use address from _CBA if present, otherwise lookup MCFG */
@@ -141,6 +142,15 @@ pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root)
cfgres.start = root->mcfg_addr + bus_res->start * bsz;
cfgres.end = cfgres.start + resource_size(bus_res) * bsz - 1;
cfgres.flags = IORESOURCE_MEM;
+
+ adev = acpi_resource_consumer(&cfgres);
+ if (adev)
+ dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres,
+ dev_name(&adev->dev));
+ else
+ dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n",
+ &cfgres);
+
cfg = pci_ecam_create(dev, &cfgres, bus_res, &pci_generic_ecam_ops);
if (IS_ERR(cfg)) {
dev_err(dev, "%04x:%pR error %ld mapping ECAM\n", seg, bus_res,
--
2.9.3