APEI is currently implemented so that it depends on x86 hardware. The primary dependency is that GHES uses the x86 NMI for hardware error notification and MCE for memory error handling. These patches remove that dependency.
Other APEI features such as error reporting via external IRQ, error serialization, or error injection, do not require changes to use them on non-x86 architectures.
The following patch set eliminates the APEI Kconfig x86 dependency by making these changes: - treat NMI notification as GHES architecture - HAVE_ACPI_APEI_NMI - group and wrap around #ifdef CONFIG_HAVE_ACPI_APEI_NMI code which is used only for NMI path - identify architectural boxes and abstract it accordingly (tlb flush and MCE) - rework ioremap for both IRQ and NMI context
NMI code is kept in ghes.c file since NMI and IRQ context are tightly coupled.
Note, these patches introduce no functional changes for x86. The NMI notification feature is hard selected for x86. Architectures that want to use this feature should also provide NMI code infrastructure.
V1->V2 - address Borislav's comment - abstract arch-specific calls instead of wrapping into the #ifdef
V2->V3 - address Robert's comment - disable ACPI_APEI_NMI selection so that it is hard selected by arch Kconfig - rename ACPI_APEI_NMI to ARCH_HAS_ACPI_APEI_NMI
V3->V4 - do not abstract NMI calls for archs which do not support it - merge some of patches to make review process easier
Tomasz Nowicki (3): apei, mce: Factor out APEI architecture specific MCE calls. acpi, apei, ghes: Make NMI error notification to be GHES architecture extension. acpi, apei, ghes: Factor out ioremap virtual memory for IRQ and NMI context.
arch/x86/Kconfig | 2 + arch/x86/kernel/acpi/Makefile | 1 + arch/x86/kernel/acpi/apei.c | 62 +++++++++++++++ drivers/acpi/apei/Kconfig | 8 +- drivers/acpi/apei/apei-base.c | 13 ++++ drivers/acpi/apei/ghes.c | 173 ++++++++++++++++++++++++++--------------- drivers/acpi/apei/hest.c | 29 +------ include/acpi/apei.h | 4 + include/linux/nmi.h | 4 + 9 files changed, 204 insertions(+), 92 deletions(-) create mode 100644 arch/x86/kernel/acpi/apei.c