Hello Frank, On Tue, Nov 12, 2024 at 12:48:16PM -0500, Frank Li wrote: > Add three registers: doorbell_bar, doorbell_addr, and doorbell_data, > along with doorbell_done. Use pci_epf_alloc_doorbell() to allocate a > doorbell address space. > > Enable the Root Complex (RC) side driver to trigger pci-epc-test's doorbell > callback handler by writing doorbell_data to the mapped doorbell_bar's > address space. > > Set doorbell_done in the doorbell callback to indicate completion. > > To avoid broken compatibility, add new command COMMAND_ENABLE_DOORBELL > and COMMAND_DISABLE_DOORBELL. Host side need send COMMAND_ENABLE_DOORBELL > to map one bar's inbound address to MSI space. the command > COMMAND_DISABLE_DOORBELL to recovery original inbound address mapping. > > Host side new driver Host side old driver > > EP: new driver S F > EP: old driver F F > > S: If EP side support MSI, 'pcitest -B' return success. > If EP side doesn't support MSI, the same to 'F'. > > F: 'pcitest -B' return failure, other case as usual. > > Tested-by: Niklas Cassel <cassel@xxxxxxxxxx> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx> > --- > Change from v5 to v6 > - rename doorbell_addr to doorbell_offset Is there a reason why you chose to not incorporate the helper function that I suggested here: https://lore.kernel.org/linux-pci/ZzMtKUFi30_o6SwL@ryzen/ I didn't see any reply from you to that message. Personally I think that it is nice to have the alignment code in a single function, rather than duplicating the code. The helper also looks quite similar to how we do outbound address translation alignment: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/commit/?h=endpoint&id=e73ea1c2d4d8f7ba5daaf7aa51171f63cf79bcd8 so that people will recognize the pattern more easily. But I guess you didn't like my suggestion? (Which is fine, but I would have expected some motivation.) Kind regards, Niklas
