On Tue, Jan 18, 2022 at 05:25:15PM +0000, Jonathan Cameron wrote: > PCI Data Object Exchange [1] provides a mailbox interface used as the > transport for various protocols defined by PCI-SIG and others. Make the > limited information in config space available. Note the Read/Write > Mailbox registers themselves are not currently parsed as the usefulness > of accessing one dword of a protocol is probably limited. > > In future, operating systems may provide means to safely query the > supported protocols, but those have not yet been defined. > > Example output: > > Capabilities: [190 v1] Data Object Exchange > DOECap: IntSup:+ > Interrupt Message Number: 001 > DOECtl: IntEn:- > DOESta: Busy:- IntSta:- Error:- ObjectReady:- Typical lspci output omits the ":" for each field, e.g., from your test: > + DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq- > + RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop- > [1] Data Object Exchange (DOE) ECN, approved 12 March 2020 DOE is included in the just-released PCIe r6.0 base spec, so we should cite that (PCIe r6.0, sec 6.30, 7.9.24). Bjorn
