Ongoing discussion on patch 4/9 [1]: [1] https://lore.kernel.org/linux-pci/20200810103252.00000318@xxxxxxxxxx/ Changes since v2 [2]: - Fix comment header for get_port_device_capability(). - Remove pcie_aer_is_native() check in pcie_do_recovery(). - Fix wording of error message in aer_inject(). - Use "non-native handling" in place of "firmware first" (Jonathan Cameron) - Prefer patches based on pci/master. - Correct order of tags, especially when using Co-developed-by. - Fix two patches ensuring that most important words appear early in one-liner. - Check on type for bitmap in pcie_walk_rciep_devfn(). However, due to use of for_each_set_bit() macro, const unsigned long is needed. Unchanged. - Matching pci_dev_put() needed where pci_get_slot() is used. - Read the RCEC Associated Endpoint Capabilities and cache them at enumeration time, e.g., pci_init_capabilities(). - Remove unnecessary use of pci_find_bus() and corresponding check on value. - Replace use of pdev/pbus with dev/bus (preferred naming style). - Mention name of new function pci_walk_dev_affected() in 4/9. - Use "()" after function names in log for 4/9. - Fix width to wrap within 75 col for 4/9. - Use word "bridge" in place of "port" in function comment. - Fix style in conditional in pci_walk_dev_affected(). (Bjorn Helgaas) [2] https://lore.kernel.org/linux-pci/20200804194052.193272-1-sean.v.kelley@xxxxxxxxx/ 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. Jonathan Cameron (1): PCI/AER: Extend AER error handling to RCECs Qiuxu Zhuo (6): PCI/RCEC: Add RCEC class code and extended capability PCI/RCEC: Bind RCEC devices to the Root Port driver PCI/RCEC: Add pcie_walk_rcec() to walk associated RCiEPs PCI/AER: Apply function level reset to RCiEP on fatal error PCI: Add 'rcec' field to pci_dev for associated RCiEPs PCI/AER: Add RCEC AER error injection support Sean V Kelley (3): PCI/RCEC: Cache RCEC capabilities in pci_init_capabilities() PCI/AER: Add RCEC AER handling PCI/PME: Add RCEC PME handling drivers/pci/pci.h | 22 ++++++ drivers/pci/pcie/Makefile | 2 +- drivers/pci/pcie/aer.c | 36 ++++++--- drivers/pci/pcie/aer_inject.c | 5 +- drivers/pci/pcie/err.c | 85 +++++++++++++++++---- drivers/pci/pcie/pme.c | 15 +++- drivers/pci/pcie/portdrv_core.c | 8 +- drivers/pci/pcie/portdrv_pci.c | 20 ++++- drivers/pci/pcie/rcec.c | 128 ++++++++++++++++++++++++++++++++ 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, 300 insertions(+), 36 deletions(-) create mode 100644 drivers/pci/pcie/rcec.c -- 2.28.0
