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Date: Sat, 7 Feb 2015 10:04:32 +0800
From: Shannon Zhao <zhaoshenglong@huawei.com>
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Subject: Re: [Qemu-devel] [RFC PATCH v2 09/11] hw/arm/virt-acpi-build:
	Generate XSDT table
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To: Laszlo Ersek <lersek@redhat.com>, Igor Mammedov <imammedo@redhat.com>
Cc: peter.maydell@linaro.org, hangaohuai@huawei.com, mst@redhat.com, a.spyridakis@virtualopensystems.com, claudio.fontana@huawei.com, qemu-devel@nongnu.org, peter.huangpeng@huawei.com, hanjun.guo@linaro.org, wanghaibin.wang@huawei.com, pbonzini@redhat.com, christoffer.dall@linaro.org

On 2015/2/4 0:51, Laszlo Ersek wrote:
> On 02/03/15 17:19, Igor Mammedov wrote:
>> On Thu, 29 Jan 2015 16:37:11 +0800
>> Shannon Zhao <zhaoshenglong@huawei.com> wrote:
>>
>>> XDST points to other tables except FACS & DSDT.
>> Is there any reason to use XSDT instead of RSDT?
>> If ACPI tables are below 4Gb which probably would
>> be the case then RSDT could be used just fine and
>> we could share more code between x86 and ARM.
>>
>> Laszlo,
>> Do you know if OVMF allocates memory below 4G address range?
> 
> Yes, it does.
> 
> https://github.com/tianocore/edk2/blob/master/OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c#L162
> 
> RSDT should suffice.
> 

Ok, will rethink about this.

-- 
Thanks,
Shannon