[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH] Improve the current FLR logic


  • To: "Yuji Shimada" <shimada-yxb@xxxxxxxxxxxxxxx>
  • From: "Neo Jia" <neojia@xxxxxxxxx>
  • Date: Tue, 30 Sep 2008 23:53:22 -0700
  • Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Keir Fraser <keir.fraser@xxxxxxxxxxxxx>, "Cui, Dexuan" <dexuan.cui@xxxxxxxxx>
  • Delivery-date: Tue, 30 Sep 2008 23:53:51 -0700
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=Yu/xx+QSO8ZTZKKWuKbMVP0bOyonRfo1f73u7cKOTewpabf755LfPzc9+0cWfM6jmx KeffLxV/YdgVLjr9DhhxEpeQhWjtIcvAIamkzQAEy6/b1j8fpJvdHsSrzPfzSjpqszTq 8BlVlBQaexDU5IwVAznc8zRywCRZ3KzektVBI=
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>

Yuji,

Could you show me how to use the hotplug method to restore the
register? Also, in the current implementation, we just read 4 bytes
each time and write them from 0 to 256 - 4. Will this cause any side
effect?

Thanks,
Neo

On Thu, Jul 17, 2008 at 2:33 AM, Yuji Shimada
<shimada-yxb@xxxxxxxxxxxxxxx> wrote:
> On Sat, 12 Jul 2008 20:37:34 +0800
> "Cui, Dexuan" <dexuan.cui@xxxxxxxxx> wrote:
>
>> I'd like to ask for your comments, and test feedbacks. Thank you very
>> much!
>
> There is a problem with the device reconfiguring logic. xend saves all
> Configuration Register's values before reset. And xend writes the
> values to the registers after reset. This means the resister's values
> which are configured by guest software are restore. Guest software
> setting should be cleared.
>
> I think the following Configuration Resister should be reconfigured to
> correct values after reset. And other registers should not be
> reconfigured after reset if there is no reason.
>
> - It is necessary to write the base address of the resource allocated
>  by the dom0 kernel to the following resister.
>    - Base Address Register
>
> - When dom0 starts, the values configured by firmware should be saved,
>  and the values should be written to the following resisters after
>  reset. The reason is that firmware configures them to archive system
>  specific functions. Especially, the registers relating error reporting
>  are configured to collect error information. If this configured values
>  is changed, some functions might be lost.
>  Instead of save/restore, it is good way to write the value from _HPX
>  method to registers, I think. _HPX method returns the value to write
>  to registers.
>    - Cache-line size Register
>    - Latency timer Register
>    - Enable SERR Bit/Enable PERR Bit in Device Control Register
>    - Uncorrectable Error Mask Register
>    - Uncorrectable Error Severity Register
>    - Correctable Error Mask Register
>    - Advanced Error Capabilities and Control Register
>    - Device Control Register
>    - Link Control Register
>    - Secondary Uncorrectable Error Severity Register
>    - Secondary Uncorrectable Error Mask Register
>    - Device Control 2 Register
>    - Link Control 2 Register
>
> - The following resister should be configured to "0".
>    - PME Enable Bit/PME Status Bit in PCI Power Management
>      Control/Status Register
>
> I would like to discuss this logic more.
>
> Thanks.
>
> --
> Yuji Shimada
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
>



-- 
I would remember that if researchers were not ambitious
probably today we haven't the technology we are using!

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.