On Tue, Apr 11, 2017 at 01:28:48PM +0100, Lorenzo Pieralisi wrote: > The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and Posting") > mandate non-posted configuration transactions. As further highlighted in > the PCIe specifications (4.0 - Rev0.3, "Ordering Considerations for the > Enhanced Configuration Access Mechanism"), through ECAM and > ECAM-derivative configuration mechanism, the memory mapped transactions > from the host CPU into Configuration Requests on the PCI express fabric > may create ordering problems for software because writes to memory > address are typically posted transactions (unless the architecture can > enforce through virtual address mapping non-posted write transactions > behaviour) but writes to Configuration Space are not posted on the PCI > express fabric. > > Include the asm-generic ioremap_nopost() implementation (currently > falling back to ioremap_nocache()) to provide a non-posted writes > ioremap interface to kernel subsystems. > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Cc: Niklas Cassel <nks@xxxxxxxxxxx> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> For the CRIS-part: Acked-by: Jesper Nilsson <jesper.nilsson@xxxxxxxx> /^JN - Jesper Nilsson -- Jesper Nilsson -- jesper.nilsson@xxxxxxxx