Per the PCI Firmware spec, r3.2, sec 4.5.1, the OS can request control of AER via bit 3 of the _OSC Control Field. In the returned value of the Control Field: The firmware sets [bit 3] to 1 to grant control over PCI Express Advanced Error Reporting. ... after control is transferred to the operating system, firmware must not modify the Advanced Error Reporting Capability. If control of this feature was requested and denied or was not requested, firmware returns this bit set to 0. Previously the pci_root driver looked at the HEST FIRMWARE_FIRST bit to determine whether to request ownership of the AER Capability. This was based on ACPI spec v6.3, sec 18.3.2.4, and similar sections, which say things like: Bit [0] - FIRMWARE_FIRST: If set, indicates that system firmware will handle errors from this source first. Bit [1] - GLOBAL: If set, indicates that the settings contained in this structure apply globally to all PCI Express Devices. These ACPI references don't say anything about ownership of the AER Capability. Remove use of the FIRMWARE_FIRST bit and rely only on the _OSC bit to determine whether we have control of the AER Capability.
Showing the changes to include/linux (1 of 3 files). Show all
Unified · Split
| @@ -125,10 +125,4 @@ static inline void acpi_pci_add_bus(struct pci_bus *bus) { } · 124 unmodified lines | |||
| 125 | static inline void acpi_pci_remove_bus(struct pci_bus *bus) { } | 125 | static inline void acpi_pci_remove_bus(struct pci_bus *bus) { } |
| 126 | #endif /* CONFIG_ACPI */ | 126 | #endif /* CONFIG_ACPI */ |
| 127 | 127 | ||
| 128 | #ifdef CONFIG_ACPI_APEI | ||
| 129 | extern bool aer_acpi_firmware_first(void); | ||
| 130 | #else | ||
| 131 | static inline bool aer_acpi_firmware_first(void) { return false; } | ||
| 132 | #endif | ||
| 133 | |||
| 134 | #endif /* _PCI_ACPI_H_ */ | 128 | #endif /* _PCI_ACPI_H_ */ |