On Wednesday 27 May 2015 21:56:27 Zhou Wang wrote: > On 2015/5/26 16:02, Arnd Bergmann wrote: > > On Tuesday 26 May 2015 10:49:51 Zhou Wang wrote: > >> > >> I am a little confused that pci_sys_data is still needed as we don't use the code > >> in bios32. What was the problem you met? Could you share me more information? Then > >> let's see how to solve the problem. > >> > > > > The PCI core code still calls pcibios_align_resource(), which will try to > > use the dev->sysdata pointer as 'struct pci_sys_data'. To solve this, we > > Thanks for reminding. > > > need to change the pci-mvebu driver and the core code first to let the > > It seams that only pci-mvebu implemented align_resource callback in ARM ? Correct. The pointer in struct pci_sys_data was added for this driver, and no other driver has needed it so far. > > driver override pcibios_align_resource() through an operation in > > struct pci_host_bridge. > > > > The other remaining use of dev->sysdata is the ARM pcibios_msi_controller() > > function that overrides the generic implementation. To solve this, we need > > to change the five remaining drivers that set hw_pci->msi_ctrl to use > > the new generic method, and remove the ARM specific implementation. > > Yes, that is better if we can do like this. But for pcie-designware, can we > just set bus->msi = &dw_pcie_msi_chip and get msi controller using dev->bus->msi > in pci_msi_controller()? Yes, that works. However there are two problems with the approach: - we have to change all PCI host drivers on ARM to do this in order to remove the ARM-specific pcibios_msi_controller() function - it's possible that there are dw_pcie implementations that do not include an MSI controller, so that pointer would be NULL, which leads to the core code to still call the ARM-specific pcibios_msi_controller() function unless we remove it. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
