Forum Discussion
Altera_Forum
Honored Contributor
12 years agoIt turned out to be a driver issue.
Apparently, pci_disable_device() also disables bus mastering bit in pci config, which is enabled by default in Altera chaining DMA example. However, pci_enable_device() does not turned on bus mastering config bit, pci_set_master() should be called in the probe function, otherwise DMAs would not work.