Hello Shannon,
On 07/06/16 02:07, Shannon Zhao wrote:
On 2016/6/6 23:48, Julien Grall wrote:
On 06/06/16 13:26, Wei Liu wrote:
On Tue, May 31, 2016 at 01:02:52PM +0800, Shannon Zhao wrote:
From: Shannon Zhao <shannon.z...@linaro.org>
The design of this feature is described as below.
Firstly, the toolstack (libxl) generates the ACPI tables according the
number of vcpus and gic controller.
Then, it copies these ACPI tables to DomU memory space and passes
them to UEFI firmware through the "ARM multiboot" protocol.
At last, UEFI gets the ACPI tables through the "ARM multiboot" protocol
and installs these tables like the usual way and passes both ACPI and DT
information to the Xen DomU.
Currently libxl only generates RSDP, XSDT, GTDT, MADT, FADT, DSDT tables
since it's enough now.
This has been tested using guest kernel with the Dom0 ACPI support
patches which could be fetched from:
https://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/log/?h=efi/arm-xen
Shannon Zhao (14):
libxl/arm: Fix the function name in error log
libxl/arm: Factor out codes for generating DTB
libxc: Add placeholders for ACPI tables blob and size
tools: add ACPI tables relevant definitions
libxl/arm: Construct ACPI GTDT table
libxl/arm: Construct ACPI FADT table
libxl/arm: Construct ACPI DSDT table
libxl/arm: Construct ACPI MADT table
libxl/arm: Construct ACPI XSDT table
libxl/arm: Construct ACPI RSDP table
libxl/arm: Initialize domain param HVM_PARAM_CALLBACK_IRQ
libxl/arm: Add ACPI module
libxl/arm: initialize memory information of ACPI blob
libxc/xc_dom_core: Copy ACPI tables to guest memory space
After going through this series, I think the code mostly looks good.
There is one higher level question: you seem to have put a lot of the
table construction code in libxl, while I failed to see why specific
libxl information is needed. Have you considered moving the code to
libxc?
I would rather avoid to have the device tree built by libxl and ACPI
tables built by libxc.
I don't remember why we have decided to implement DT building in libxl,
I guess it is because we need to know which GIC version is used (GICv2
vs GICv3).
In the long run, we might also need to have more part of the firmware
configurable (performance monitor support, memory layout, UART...).
Most of those information are available easily in libxl, we would to
export them of libxc.
Yes, and one more reason is that to support ACPI, it also needs to add
the ACPI multiboot module in DT.
I don't consider this as a reason for building the ACPI tables in libxl.
I am more concerned about building the firmwares in different place.
If we decide to build the ACPI tables in libxc, then the code to build
the device tree should move in libxc too.
Regards,
--
Julien Grall
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
