• Michael Neuling's avatar
    cxl: Add AFU virtual PHB and kernel API · 6f7f0b3d
    Michael Neuling authored
    This patch does two things.
    
    Firstly it presents the Accelerator Function Unit (AFUs) behind the POWER
    Service Layer (PSL) as PCI devices on a virtual PCI Host Bridge (vPHB).  This
    in in addition to the PSL being a PCI device itself.
    
    As part of the Coherent Accelerator Interface Architecture (CAIA) AFUs can
    provide an AFU configuration.  This AFU configuration recored is architected to
    be the same as a PCI config space.
    
    This patch sets discovers the AFU configuration records, provides AFU config
    space read/write functions to these configuration records.  It then enumerates
    the PCI bus.  It also hooks in PCI ops where appropriate.  It also destroys the
    vPHB when the physical card is removed.
    
    Secondly, it add an in kernel API for AFU to use CXL.  AFUs must present a
    driver that firstly binds as a PCI device.  This PCI device can then be using
    to do CXL specific operations (that can't sit in the PCI ops) using this API.
    Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
    Acked-by: default avatarIan Munsie <imunsie@au1.ibm.com>
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    6f7f0b3d
cxl.h 24.7 KB