Re: [PATCH] pci: pciehp update the slot bridge res to get big range for pcie devices

From: Eric W. Biederman
Date: Thu Oct 29 2009 - 11:43:48 EST


Yinghai Lu <yinghai@xxxxxxxxxx> writes:

> Eric W. Biederman wrote:
>> Yinghai Lu <yinghai@xxxxxxxxxx> writes:
>>> after closing look up the code, it looks it will not break your setup.
>>>
>>> 1. before the patches:
>>> a. when master card is inserted, all bridge in that card will get assigned with min_size
>>> b. when new cards is inserted to those slots in master card, will get assigned in the bridge size.
>>>
>>> 2. after the patches: v5
>>> a. booted up, all leaf bridge mmio get clearred.
>>> b. when master card is inserted, all bridge in that card will get assigned with min_size, and master bridge will be sum of them
>>> c. when new cards is inserted to those slots in master card, will get assigned in the bridge size.
>>>
>>> can you check those two patches in your setup to verify it?
>>
>> I have a much simpler case I will break, as I tried something similar by accident.
> which kernel version?
>>
>> AMD cpu MCP55 with one pcie port setup as hotplug.
>> The system only has 2GB of RAM. So plenty of space for pcie devices.
>
> one or two ht chains?

One chain.

> do you still have lspci -tv with it?
>
>>
>> If the firmware assigns nothing and linux at boot time assigns the pci mmio space:
>> Reads from the bar of the hotplugged device work
>> Writes to the bar of the hotplugged device, cause further writes to go to lala land.
>>
>> So I had to have the firmware make the assignment, because only it knows the
>> details of the hidden AMD bar registers for each hypertransport chain etc.
>
> that mean kernel doesn't get peer root bus res probed properly

How do you do that without having drivers for the peer root bus?

Eric
--
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/