acpi: DSDT/SSDT runtime patching

Here's an updated revision of acpi runtime patching patchset. Lightly tested.

changes in v4:
- split PCI hotplug handling out to a separate SSDT

Changes in v3:
- change ssdt generation code to get rid of hardcoded offsets
- enhancements to acpi_extract: add more extract methods ACPI_EXTRACT_NAME_WORD_CONST - extract a Word Const object from Name() ACPI_EXTRACT_NAME_BYTE_CONST - extract a Byte Const object from Name() ACPI_EXTRACT_PROCESSOR_START - start of Processor() block ACPI_EXTRACT_PROCESSOR_STRING - extract a NameString from Processor() ACPI_EXTRACT_PROCESSOR_END - offset at last byte of Processor() + 1

Changes in v2:
- tools rewritten in python
- Original ASL retains _EJ0 methods, BIOS patches that to EJ0_
- generic ACP_EXTRACT infrastructure that can match Method and Name Operators
- instead of matching specific method name, insert tags in original DSL source and match that to AML

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Here's a bug: guest thinks it can eject VGA device and ISA bridge.

[root@dhcp74-172 ~]#lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02) 00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II] 00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II] 00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:02.0 VGA compatible controller: Cirrus Logic GD 5446
00:03.0 PCI bridge: Red Hat, Inc. Device 0001
00:04.0 Ethernet controller: Qumranet, Inc. Virtio network device
00:05.0 SCSI storage controller: Qumranet, Inc. Virtio block device
01:00.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 03)

[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/1/
adapter address attention latch module power
[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/2/
adapter address attention latch module power

[root@dhcp74-172 ~]# echo 0 > /sys/bus/pci/slots/2/power
[root@dhcp74-172 ~]# lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02) 00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II] 00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II] 00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:03.0 PCI bridge: Red Hat, Inc. Device 0001
00:04.0 Ethernet controller: Qumranet, Inc. Virtio network device
00:05.0 SCSI storage controller: Qumranet, Inc. Virtio block device
01:00.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 03)

This is wrong because slots 1 and 2 are marked as not hotpluggable in qemu.

The reason is that our acpi tables declare both _RMV with value 0, and _EJ0 method for these slots. What happens in this case is undocumented by ACPI spec, so linux ignores _RMV, and windows seems to ignore _EJ0.

The correct way to suppress hotplug is not to have _EJ0, so this is what this patch does: it probes PIIX and modifies DSDT to match.

With these patches applied, we get:

[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/1/
address
[root@dhcp74-172 ~]# ls /sys/bus/pci/slots/2/
address

Michael S. Tsirkin (3):
acpi: add ssdt for pci hotplug
acpi: EJ0 method name patching
acpi: remove _RMV

 Makefile           |    2 +-
 src/acpi-dsdt.dsl  |  132 +--------------------------------------------------
 src/acpi.c         |   40 ++++++++++++++++
 src/ssdt-pcihp.dsl |   98 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 142 insertions(+), 130 deletions(-)
 create mode 100644 src/ssdt-pcihp.dsl

1.7.5.53.gc233e