acpi: cpuhp: document CPHP_GET_CPU_ID_CMD command

Commit 3a61c8db9d25 introduced CPHP_GET_CPU_ID_CMD command but
did not sufficiently describe it. Fix it by adding missing command
documentation.

Fixes: 3a61c8db9d25 ("acpi: cpuhp: add CPHP_GET_CPU_ID_CMD command")
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <1580306781-228371-1-git-send-email-imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/docs/specs/acpi_cpu_hotplug.txt b/docs/specs/acpi_cpu_hotplug.txt
index a8ce5e74028fe0280ac71fdc1b58ff8e24cf45e2..9bb22d1270a902fca0f7e0e7564eac1de567475e 100644 (file)
--- a/docs/specs/acpi_cpu_hotplug.txt
+++ b/docs/specs/acpi_cpu_hotplug.txt
@@ -94,6 +94,8 @@ write access:
                register in QEMU
             2: following writes to 'Command data' register set OST status
                register in QEMU
+            3: following reads from 'Command data' and 'Command data 2' return
+               architecture specific CPU ID value for currently selected CPU.
             other values: reserved
     [0x6-0x7] reserved
     [0x8] Command data: (DWORD access)