DDE Linux26 in the Hurd

Da Zheng zhengda1936 at gmail.com
Wed Jan 27 13:41:46 CET 2010


On 10-1-27 下午8:03, Björn Döbel wrote:
>> I have managed to port DDE linux26 to the Hurd. At least it works with NIC
>> drivers now.
> Congratulations. :)
Thank you.
>> A few problems:
>> 1. dde linux26 doesn't support multiple PCI buses. Unfortunately, my virtual
>> machine has two PCI buses: bus 0 and bus 2. Now I have to hardcode the bus
>> numbers in the code. Do you have plan to support multiple PCI buses?
> Our approach is to provide the application with a single logical PCI bus
> within DDEKit and have a management component that parses the real PCI
> bus and multiplexes accesses. Have a look at l4/pkg/l4io. As in most of
> the cases you only use one device within a DDEKit-based application, we
> did not see any real benefit of supporting multiple PCI buses in DDE.
OK, I see your point and I believe that one device doesn't use two buses, but I
didn't see how a logical PCI bus is mapped to a physical one. ddekit_pci_init calls
        err = l4io_pci_find_device(~0, ~0, start, &l4dev);
to search for buses, which calls a RPC to the kernel, but every DDEKIT
application starts with 0. I don't see where is your management component and
how it chooses the right bus for the device.

>> 2. DDE Linux26 doesn't support sound card drivers.
>> Does DDE Linux26 support the block device and character device?
> The answer for all points is that this is usually a matter of adding the
> corresponding Linux code and maybe some glue code. We did this for
> character, sound and block devices to a certain point. However, there is
> no releasable code, yet.
So are you still working on supporting character, sound and block devices?

Thank you,
Zheng Da

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