From e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb Mon Sep 17 00:00:00 2001 From: Yang Zhang Date: Fri, 28 Aug 2015 09:58:54 +0800 Subject: Add qemu 2.4.0 Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang --- qemu/docs/specs/acpi_cpu_hotplug.txt | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 qemu/docs/specs/acpi_cpu_hotplug.txt (limited to 'qemu/docs/specs/acpi_cpu_hotplug.txt') diff --git a/qemu/docs/specs/acpi_cpu_hotplug.txt b/qemu/docs/specs/acpi_cpu_hotplug.txt new file mode 100644 index 000000000..340b751a9 --- /dev/null +++ b/qemu/docs/specs/acpi_cpu_hotplug.txt @@ -0,0 +1,24 @@ +QEMU<->ACPI BIOS CPU hotplug interface +-------------------------------------- + +QEMU supports CPU hotplug via ACPI. This document +describes the interface between QEMU and the ACPI BIOS. + +ACPI GPE block (IO ports 0xafe0-0xafe3, byte access): +----------------------------------------- + +Generic ACPI GPE block. Bit 2 (GPE.2) used to notify CPU +hot-add/remove event to ACPI BIOS, via SCI interrupt. + +CPU present bitmap for: + ICH9-LPC (IO port 0x0cd8-0xcf7, 1-byte access) + PIIX-PM (IO port 0xaf00-0xaf1f, 1-byte access) +--------------------------------------------------------------- +One bit per CPU. Bit position reflects corresponding CPU APIC ID. +Read-only. + +CPU hot-add/remove notification: +----------------------------------------------------- +QEMU sets/clears corresponding CPU bit on hot-add/remove event. +CPU present map read by ACPI BIOS GPE.2 handler to notify OS of CPU +hot-(un)plug events. -- cgit 1.2.3-korg