From: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
To: <qemu-devel@nongnu.org>, <qemu-arm@nongnu.org>,
<eric.auger@redhat.com>, <imammedo@redhat.com>
Cc: peter.maydell@linaro.org, sameo@linux.intel.com,
ard.biesheuvel@linaro.org, linuxarm@huawei.com,
xuwei5@hisilicon.com, shannon.zhaosl@gmail.com,
sebastien.boeuf@intel.com, lersek@redhat.com
Subject: [Qemu-devel] [PATCH-for-4.2 v9 10/12] docs/specs: Add ACPI GED documentation
Date: Tue, 13 Aug 2019 22:05:37 +0100 [thread overview]
Message-ID: <20190813210539.31164-11-shameerali.kolothum.thodi@huawei.com> (raw)
In-Reply-To: <20190813210539.31164-1-shameerali.kolothum.thodi@huawei.com>
Documents basic concepts of ACPI Generic Event device(GED)
and interface between QEMU and the ACPI BIOS.
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
---
docs/specs/acpi_hw_reduced_hotplug.txt | 60 ++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
create mode 100644 docs/specs/acpi_hw_reduced_hotplug.txt
diff --git a/docs/specs/acpi_hw_reduced_hotplug.txt b/docs/specs/acpi_hw_reduced_hotplug.txt
new file mode 100644
index 0000000000..46839be5ff
--- /dev/null
+++ b/docs/specs/acpi_hw_reduced_hotplug.txt
@@ -0,0 +1,60 @@
+QEMU<->ACPI BIOS Generic Event Device interface
+
+The ACPI Generic Event Device (GED) is a HW reduced platform
+specific device introduced in ACPI v6.1 that handles all platform
+events, including the hotplug ones. GED is modelled as a device
+in the namespace with a _HID defined to be ACPI0013. This document
+describes the interface between QEMU and the ACPI BIOS.
+
+GED allows HW reduced platforms to handle interrupts in ACPI ASL
+statements. It follows a very similar approach like the _EVT method
+from GPIO events. All interrupts are listed in _CRS and the handler
+is written in _EVT method. However, Qemu implementation uses a single
+interrupt for the GED device, relying on IO memory region to communicate
+the type of device affected by the interrupt. This way, we can support
+up to 32 events with a unique interrupt.
+
+Here is an example.
+
+Device (\_SB.GED)
+{
+ Name (_HID, "ACPI0013")
+ Name (_UID, Zero)
+ Name (_CRS, ResourceTemplate ()
+ {
+ Interrupt (ResourceConsumer, Edge, ActiveHigh, Exclusive, ,, )
+ {
+ 0x00000029,
+ }
+ })
+ OperationRegion (EREG, SystemMemory, 0x09080000, 0x04)
+ Field (EREG, DWordAcc, NoLock, WriteAsZeros)
+ {
+ ESEL, 32
+ }
+ Method (_EVT, 1, Serialized)
+ {
+ Local0 = ESEL // ESEL = IO memory region which specifies the
+ // device type.
+ If (((Local0 & One) == One))
+ {
+ MethodEvent1()
+ }
+ If ((Local0 & 0x2) == 0x2)
+ {
+ MethodEvent2()
+ }
+ ...
+ }
+}
+
+GED IO interface (4 byte access):
+read access:
+ [0x0-0x3] Event selector bit field(32 bit) set by Qemu.
+ bits:
+ 1: Memory hotplug event
+ 2: System power down event
+ 3-31: Reserved
+
+write_access:
+ Nothing is expected to be written into GED IO memory
--
2.17.1
next prev parent reply other threads:[~2019-08-13 21:12 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-13 21:05 [Qemu-devel] [PATCH-for-4.2 v9 00/12] ARM virt: ACPI memory hotplug support Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 01/12] hw/acpi: Make ACPI IO address space configurable Shameer Kolothum
2019-08-15 8:42 ` Shameerali Kolothum Thodi
2019-08-29 8:45 ` Igor Mammedov
2019-08-29 11:04 ` Shameerali Kolothum Thodi
2019-08-29 12:38 ` Igor Mammedov
2019-08-29 13:45 ` Shameerali Kolothum Thodi
2019-09-01 11:17 ` Auger Eric
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 02/12] hw/acpi: Do not create memory hotplug method when handler is not defined Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 03/12] hw/acpi: Add ACPI Generic Event Device Support Shameer Kolothum
2019-09-01 11:17 ` Auger Eric
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 04/12] hw/arm/virt: Add memory hotplug framework Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 05/12] hw/arm/virt: Add 4.2 machine type Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 06/12] hw/arm/virt: Enable device memory cold/hot plug with ACPI boot Shameer Kolothum
2019-09-01 11:18 ` Auger Eric
2019-09-01 11:22 ` Auger Eric
2019-09-02 9:34 ` Shameerali Kolothum Thodi
2019-09-02 9:21 ` Shameerali Kolothum Thodi
2019-09-02 9:32 ` Auger Eric
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 07/12] hw/arm/virt-acpi-build: Add PC-DIMM in SRAT Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 08/12] hw/arm: Factor out powerdown notifier from GPIO Shameer Kolothum
2019-09-02 7:37 ` Auger Eric
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 09/12] hw/arm: Use GED for system_powerdown event Shameer Kolothum
2019-09-02 7:37 ` Auger Eric
2019-08-13 21:05 ` Shameer Kolothum [this message]
2019-09-01 11:20 ` [Qemu-devel] [PATCH-for-4.2 v9 10/12] docs/specs: Add ACPI GED documentation Auger Eric
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 11/12] tests: add dummy ACPI tables for arm/virt board Shameer Kolothum
2019-08-13 21:05 ` [Qemu-devel] [PATCH-for-4.2 v9 12/12] tests: Add bios tests to arm/virt Shameer Kolothum
2019-08-14 6:46 ` [Qemu-devel] [PATCH-for-4.2 v9 00/12] ARM virt: ACPI memory hotplug support no-reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190813210539.31164-11-shameerali.kolothum.thodi@huawei.com \
--to=shameerali.kolothum.thodi@huawei.com \
--cc=ard.biesheuvel@linaro.org \
--cc=eric.auger@redhat.com \
--cc=imammedo@redhat.com \
--cc=lersek@redhat.com \
--cc=linuxarm@huawei.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-arm@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=sameo@linux.intel.com \
--cc=sebastien.boeuf@intel.com \
--cc=shannon.zhaosl@gmail.com \
--cc=xuwei5@hisilicon.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).