On Wed, 30 Sep 2020 14:58:07 -0700 Sean V Kelley <seanvk.dev@xxxxxxxxxxxxxxxx> wrote: > From: Sean V Kelley <sean.v.kelley@xxxxxxxxx> > > Changes since v6 [1]: > > - Remove unused includes in rcec.c. > - Add local variable for dev->rcec_ea. > - If no valid capability version then just fill in nextbusn = 0xff. > - Leave a blank line after pci_rcec_init(dev). > - Reword commit w/ "Attempt to do a function level reset for an RCiEP on fatal error." > - Change An RCiEP found on bus in range -> An RCiEP found on a different bus in range > - Remove special check on capability version if you fill in nextbusn = 0xff. > - Remove blank lines in pcie_link_rcec header. > - Fix indentation aer.c. > (Jonathan Cameron) > > - Relocate enabling of PME for RCECs to later RCEC handling additions to PME. > - Rename rcec_ext to rcec_ea. > - Remove rcec_cap as its use can be handled with rcec_ea. > - Add a forward declaration for struct rcec_ea. > - Rename pci_bridge_walk() to pci_walk_bridge() to match consistency with other usage. > - Separate changes to "reset_subordinate_devices" because it doesn't change the interface. > - Separate the use of "type", rename of "dev" to "bridge", the inversion of the condition and > use of pci_upstream_bridge() instead of dev->bus->self. > - Separate the conditional check (TYPE_ROOT_PORT and TYPE_DOWNSTREAM) for AER resets. > - Consider embedding RCiEP's parent RCEC in the rcec_ea struct. However, the > issue here is that we don't normally allocate the rcec_ea struct for RCiEPs and > the linkage of rcec_ea->rcec is not necessarily more clear. > - Provide more comment on the non-native case for clarity. > (Bjorn Helgaas) > > [1] https://lore.kernel.org/linux-pci/20200922213859.108826-1-seanvk.dev@xxxxxxxxxxxxxxxx/ > > Root Complex Event Collectors (RCEC) provide support for terminating error > and PME messages from Root Complex Integrated Endpoints (RCiEPs). An RCEC > resides on a Bus in the Root Complex. Multiple RCECs can in fact reside on > a single bus. An RCEC will explicitly declare supported RCiEPs through the > Root Complex Endpoint Association Extended Capability. > > (See PCIe 5.0-1, sections 1.3.2.3 (RCiEP), and 7.9.10 (RCEC Ext. Cap.)) > > The kernel lacks handling for these RCECs and the error messages received > from their respective associated RCiEPs. More recently, a new CPU > interconnect, Compute eXpress Link (CXL) depends on RCEC capabilities for > purposes of error messaging from CXL 1.1 supported RCiEP devices. > > DocLink: https://www.computeexpresslink.org/ > > This use case is not limited to CXL. Existing hardware today includes > support for RCECs, such as the Denverton microserver product > family. Future hardware will be forthcoming. > > (See Intel Document, Order number: 33061-003US) > > So services such as AER or PME could be associated with an RCEC driver. > In the case of CXL, if an RCiEP (i.e., CXL 1.1 device) is associated with a > platform's RCEC it shall signal PME and AER error conditions through that > RCEC. > > Towards the above use cases, add the missing RCEC class and extend the > PCIe Root Port and service drivers to allow association of RCiEPs to their > respective parent RCEC and facilitate handling of terminating error and PME > messages. I took a look at the combined result of the series as well as individual patches I've acked. All looks good to me. Also ran a quick batch of tests with the non-native / no visible RCEC case and that's working as expected. Feels a bit odd too give a tested-by for the case that touches only a tiny corner of the code, but if you want to include it... Tested-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> #non-native/no RCEC Thanks, Jonathan > > > Jonathan Cameron (1): > PCI/AER: Extend AER error handling to RCECs > > Qiuxu Zhuo (5): > PCI/RCEC: Add RCEC class code and extended capability > PCI/RCEC: Bind RCEC devices to the Root Port driver > PCI/AER: Apply function level reset to RCiEP on fatal error > PCI/RCEC: Add RCiEP's linked RCEC to AER/ERR > PCI/AER: Add RCEC AER error injection support > > Sean V Kelley (7): > PCI/RCEC: Cache RCEC capabilities in pci_init_capabilities() > PCI/ERR: Rename reset_link() to reset_subordinate_device() > PCI/ERR: Use "bridge" for clarity in pcie_do_recovery() > PCI/ERR: Limit AER resets in pcie_do_recovery() > PCI/RCEC: Add pcie_link_rcec() to associate RCiEPs > PCI/AER: Add pcie_walk_rcec() to RCEC AER handling > PCI/PME: Add pcie_walk_rcec() to RCEC PME handling > > drivers/pci/pci.h | 25 ++++- > drivers/pci/pcie/Makefile | 2 +- > drivers/pci/pcie/aer.c | 36 ++++-- > drivers/pci/pcie/aer_inject.c | 5 +- > drivers/pci/pcie/err.c | 109 +++++++++++++++---- > drivers/pci/pcie/pme.c | 15 ++- > drivers/pci/pcie/portdrv_core.c | 8 +- > drivers/pci/pcie/portdrv_pci.c | 8 +- > drivers/pci/pcie/rcec.c | 187 ++++++++++++++++++++++++++++++++ > drivers/pci/probe.c | 2 + > include/linux/pci.h | 5 + > include/linux/pci_ids.h | 1 + > include/uapi/linux/pci_regs.h | 7 ++ > 13 files changed, 367 insertions(+), 43 deletions(-) > create mode 100644 drivers/pci/pcie/rcec.c > > -- > 2.28.0 >
