在 2012年2月16日 下午5:21，Chen Jie chenj@lemote.com 写道：
Hi,
在 2012年2月15日 下午11:53，Jerome Glisse j.glisse@gmail.com 写道：
To me it looks like the CP is trying to fetch memory but the GPU memory controller fail to fullfill cp request. Did you check the PCI configuration before & after (when things don't work) My best guest is PCI bus mastering is no properly working or the PCIE GPU gart table as wrong data.
Maybe one need to drop bus master and reenable bus master to work around some bug...
Thanks for your suggestion. We've tried the 'drop and reenable master' trick, unfortunately doesn't work. The PCI configuration compare will be done later.
Update: We've checked the first 64 bytes of PCI configuration space before & after, and didn't find any difference.
Regards, -- Chen Jie