Re: [PATCH 0/5] Enable Drivers for Intel MIC X100 Coprocessors.

[Sudeep Dutt]

On Wed, 2013-07-31 at 18:46 -0700, Greg Kroah-Hartman wrote: 
> On Wed, Jul 24, 2013 at 08:31:31PM -0700, Sudeep Dutt wrote:
> > An Intel MIC X100 device is a PCIe form factor add-in coprocessor
> > card based on the Intel Many Integrated Core (MIC) architecture
> > that runs a Linux OS. It is a PCIe endpoint in a platform and therefore
> > implements the three required standard address spaces i.e. configuration,
> > memory and I/O. The host OS loads a device driver as is typical for
> > PCIe devices. The card itself runs a bootstrap after reset that
> > transfers control to the card OS downloaded from the host driver.
> > The card OS as shipped by Intel is a Linux kernel with modifications
> > for the X100 devices.
> > 
> > Since it is a PCIe card, it does not have the ability to host hardware
> > devices for networking, storage and console. We provide these devices
> > on X100 coprocessors thus enabling a self-bootable equivalent environment
> > for applications. A key benefit of our solution is that it leverages
> > the standard virtio framework for network, disk and console devices,
> > though in our case the virtio framework is used across a PCIe bus.
> > 
> > Here is a block diagram of the various components described above. The
> > virtio backends are situated on the host rather than the card given better
> > single threaded performance for the host compared to MIC and the ability of
> > the host to initiate DMA's to/from the card using the MIC DMA engine.
> > 
> >                               |
> >        +----------+           |             +----------+
> >        | Card OS  |           |             | Host OS  |
> >        +----------+           |             +----------+
> >                               |
> > +-------+ +--------+ +------+ | +---------+  +--------+ +--------+
> > | Virtio| |Virtio  | |Virtio| | |Virtio   |  |Virtio  | |Virtio  |
> > | Net   | |Console | |Block | | |Net      |  |Console | |Block   |
> > | Driver| |Driver  | |Driver| | |backend  |  |backend | |backend |
> > +-------+ +--------+ +------+ | +---------+  +--------+ +--------+
> >     |         |         |     |      |            |         |
> >     |         |         |     |Ring 3|            |         |
> >     |         |         |     |------|------------|---------|-------
> >     +-------------------+     |Ring 0+--------------------------+
> >               |               |      | Virtio over PCIe IOCTLs  |
> >               |               |      +--------------------------+
> >       +--------------+        |                   |
> >       |Intel MIC     |        |            +---------------+
> >       |Card Driver   |        |            |Intel MIC      |
> >       +--------------+        |            |Host Driver    |
> >               |               |            +---------------+
> >               |               |                   |
> >      +-------------------------------------------------------------+
> >      |                                                             |
> >      |                    PCIe Bus                                 |
> >      +-------------------------------------------------------------+
> 
> That's some nice information, why isn't it in one of the patches you
> sent, so that others can read it later on to try to figure out what is
> going on with this codebase?
> 

The description in the cover letter is also provided in PATCH 5 of the
series @ Documentation/mic/mic_overview.txt [1].
Thanks,
Sudeep Dutt

[1] https://lkml.org/lkml/2013/7/24/812

> thanks,
> 
> greg k-h





--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/