x86/PCI: Mark ATI SBx00 HPET BAR as IORESOURCE_PCI_FIXED
Bodo reported that on the Asrock M3A UCC, v3.12.6 hangs during boot unless he uses "pci=nocrs". This regression was caused by 7bc5e3f2 ("x86/PCI: use host bridge _CRS info by default on 2008 and newer machines"), which appeared in v2.6.34. The reason is that the HPET address appears in a PCI device BAR, and this address is not contained in any of the host bridge windows. Linux moves the PCI BAR into a window, but the original address was published via the HPET table and an ACPI device, so changing the BAR is a bad idea. Here's the dmesg info: ACPI: HPET id: 0x43538301 base: 0xfed00000 pci_root PNP0A03:00: host bridge window [mem 0xd0000000-0xdfffffff] pci_root PNP0A03:00: host bridge window [mem 0xf0000000-0xfebfffff] pci 0000:00:14.0: [1002:4385] type 0 class 0x000c05 pci 0000:00:14.0: reg 14: [mem 0xfed00000-0xfed003ff] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0, 0 pnp 00:06: Plug and Play ACPI device, IDs PNP0103 (active) pnp 00:06: [mem 0xfed00000-0xfed003ff] When we notice the BAR is not in a host bridge window, we try to move it, but that causes a hang shortly thereafter: pci 0000:00:14.0: no compatible bridge window for [mem 0xfed00000-0xfed003ff] pci 0000:00:14.0: BAR 1: assigned [mem 0xf0000000-0xf00003ff] This patch marks the BAR as IORESOURCE_PCI_FIXED to prevent Linux from moving it. This depends on a previous patch ("x86/PCI: Don't try to move IORESOURCE_PCI_FIXED resources") to check for this flag when pci_claim_resource() fails. Link: https://bugzilla.kernel.org/show_bug.cgi?id=68591 Reported-and-tested-by: Bodo Eggert <7eggert@gmx.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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