From 08b1c19606b5fc7f895dae4d43d507b4da4a83bf Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 30 Nov 2016 14:48:33 -0600 Subject: [PATCH] arm64: PCI: Search ACPI namespace to ensure ECAM space is reserved 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 Acked-by: Lorenzo Pieralisi --- 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 8183c9803206..216dff6c5877 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, -- 2.39.5