Modern high-end servers may support advanced RAS features, such as system device dynamic reconfiguration. On x86 and IA64 platforms, system device means processor(CPU), memory device, PCI host bridge and even computer node. The ACPI specifications have provided standard interfaces between firmware and OS to support device dynamic reconfiguraiton at runtime. This patch series introduces a new framework for system device dynamic reconfiguration based on ACPI specification, which will replace current existing system device hotplug logic embedded in ACPI processor/memory/container device drivers. The new ACPI based hotplug framework is modelled after the PCI hotplug architecture and target to achieve following goals: 1) Optimize device configuration order to achieve best performance for hot-added system devices. For best perforamnce, system device should be configured in order of memory -> CPU -> IOAPIC/IOMMU -> PCI HB. 2) Resolve dependencies among hotplug slots. You need first to remove the memory device before removing a physical processor if a hotpluggable memory device is connected to a hotpluggable physical processor. 3) Provide interface to cancel ongoing hotplug operations. It may take a very long time to remove a memory device, so provide interface to cancel the inprogress hotplug operations. 4) Support new advanced RAS features, such as socket/memory migration. 5) Provide better user interfaces to access the hotplug functionalities. 6) Provide a mechanism to detect hotplug slots by checking existence of ACPI _EJ0 method or by other hardware platform specific methods. 7) Unify the way to enumerate ACPI based hotplug slots. All hotplug slots will be enumerated by the enumeration driver (acpihp_slot), instead of by individual ACPI device drivers. 8) Unify the way to handle ACPI hotplug events. All ACPI hotplug events for system devices will be handled by a generic ACPI hotplug driver (acpihp_drv) instead of by individual ACPI device drivers. 9) Provide better error handling and error recovery. 10) Trigger hotplug events/operations by software. This feature is useful for hardware fault management and/or power saving. The new framework is composed up of three major components: 1) A system device hotplug slot enumerator driver, which enumerates hotplug slots in the system and provides platform specific methods to control those slots. 2) A system device hotplug driver, which is a platform independent driver to manage all hotplug slots created by the slot enumerator. The hotplug driver implements a state machine for hotplug slots and provides user interfaces to manage hotplug slots. 3) Several ACPI device drivers to configure/unconfigure system devices at runtime. And the whole patchset will be split into 7 parts: 1) the hotplug slot enumeration driver (acpihp_slot) 2) the system device hotplug driver (acpihp_drv) 3) enhance ACPI container driver to support new framework 4) enhance ACPI processor driver to support new framework 5) enhance ACPI memory driver to support new framework 6) enhance ACPI host bridge driver to support new framework 7) enhancments and cleanups to the ACPI core This is the first part of hotplug slot enumeration driver (acpihp_slot). And you may pull from: https://github.com/jiangliu/linux.git acpihp_slot On loading, it will scan ACPI hotplug slots for system device hotplug. For example, Intel Emerald Ridge/Quantum S4R platform has 1) 4 hotpluggable physical processors 2) 8 hotpluggable memory boards (each processor has two memory boards) 3) 1 hotpluggable IOH and 1 non-hotpluggable legacy IOH #modprobe acpihp_slot #cd /sys/bus/acpi/slots #ls -l total 0 lrwxrwxrwx CPU00 -> ../../../devices/LNXSYSTM:00/acpihp/CPU00 lrwxrwxrwx CPU01 -> ../../../devices/LNXSYSTM:00/acpihp/CPU01 lrwxrwxrwx CPU02 -> ../../../devices/LNXSYSTM:00/acpihp/CPU02 lrwxrwxrwx CPU03 -> ../../../devices/LNXSYSTM:00/acpihp/CPU03 lrwxrwxrwx IOX01 -> ../../../devices/LNXSYSTM:00/acpihp/IOX01 lrwxrwxrwx MEM00 -> ../../../devices/LNXSYSTM:00/acpihp/CPU00/MEM00 lrwxrwxrwx MEM01 -> ../../../devices/LNXSYSTM:00/acpihp/CPU00/MEM01 lrwxrwxrwx MEM02 -> ../../../devices/LNXSYSTM:00/acpihp/CPU01/MEM02 lrwxrwxrwx MEM03 -> ../../../devices/LNXSYSTM:00/acpihp/CPU01/MEM03 lrwxrwxrwx MEM04 -> ../../../devices/LNXSYSTM:00/acpihp/CPU02/MEM04 lrwxrwxrwx MEM05 -> ../../../devices/LNXSYSTM:00/acpihp/CPU02/MEM05 lrwxrwxrwx MEM06 -> ../../../devices/LNXSYSTM:00/acpihp/CPU03/MEM06 lrwxrwxrwx MEM07 -> ../../../devices/LNXSYSTM:00/acpihp/CPU03/MEM07 For each hotplug slots, it provides following sysfs interfaces: # cd CPU00/ # ls ; MEM00, MEM01 are child hotplug slots MEM00 MEM01 capabilities device object power state status subsystem uevent # cat capabilities ; show slot RAS capabilities online,offline,poweroff,hotplug # cat object ; show ACPI object corresponding to this slot \_SB_.SCK0 # cat state ; show slot state machine state configured # cat status ; show devie health status ok Jiang Liu (4): ACPIHP: introduce a framework for ACPI based system device hotplug ACPIHP: introduce acpihp_slot driver to enumerate hotplug slots ACPIHP: detect ACPI hotplug slots by checking ACPI _EJ0 method ACPIHP: implement a fake ACPI system device hotplug slot enumerator drivers/acpi/Kconfig | 42 +++ drivers/acpi/Makefile | 2 + drivers/acpi/hotplug/Makefile | 11 + drivers/acpi/hotplug/acpihp.h | 36 +++ drivers/acpi/hotplug/core.c | 543 ++++++++++++++++++++++++++++++++++++++ drivers/acpi/hotplug/slot.c | 421 +++++++++++++++++++++++++++++ drivers/acpi/hotplug/slot_ej0.c | 143 ++++++++++ drivers/acpi/hotplug/slot_fake.c | 180 +++++++++++++ include/acpi/acpi_hotplug.h | 208 +++++++++++++++ 9 files changed, 1586 insertions(+) create mode 100644 drivers/acpi/hotplug/Makefile create mode 100644 drivers/acpi/hotplug/acpihp.h create mode 100644 drivers/acpi/hotplug/core.c create mode 100644 drivers/acpi/hotplug/slot.c create mode 100644 drivers/acpi/hotplug/slot_ej0.c create mode 100644 drivers/acpi/hotplug/slot_fake.c create mode 100644 include/acpi/acpi_hotplug.h -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
