CXL accelerators are unfortunately not immune from failure. This patch set enables them to particpate in the Extended Error Handling process.
This series starts with a number of preparatory patches: - Patch 1 is cleanup: converting macros to static inlines. - Patch 2 makes sure we don't touch the hardware when it has failed. - Patches 3-5 make the 'unplug' functions idempotent, so that if we get part way through recovery and then fail, being completely unplugged as part of removal doesn't cause us to oops out. - Patches 6 and 7 refactor init and teardown paths for the adapter and AFUs, so that they can be configured and deconfigured separately from their allocation and release. - Patch 8 stops cxl_reset from breaking EEH. Patches 9 and 10 are parts of EEH. - Firstly we have a kernel flag that allows us to confidently assert the hardware will not change (be reflashed) when it it reset. We need this in order to be able to safely do EEH recovery. - We then have the EEH support itself. Finally, we add a CONFIG_CXL_EEH symbol. This allows drivers to depend on the API we provide to enable CXL EEH, or to be easily backportable if EEH is optional. Changes from v3 are minor: - Clarification of responsibility of CXL driver vs driver bound to vPHB with regards to preventing inappropriate access of hardware during recovery. - Clean up unused rc in cxl_alloc_adapter, thanks David Laight. - Break setting rc and testing rc into different lines, thanks mpe and Cyril. - If we fail to init an AFU, don't try to select the best mode. Changes from v2 are mostly minor cleanups, reflecting some review and further testing. - Use static inlines instead of macros. - Propagate PCI link state to devices on the vPHB. - Various cleanup, thanks Cyril Bur. - Use pci_channel_offline instead of a direct check. - Don't ifdef, just provide the symbol so that drivers know that the new API is available. Thanks to Cyril for patiently explaining this to me about 3 times before I understood. Changes from v1: - More comprehensive link down checks, including vPHB. - Rebased to apply cleanly to 4.2-rc4. - cxl reset changes. - CONFIG_CXL_EEH symbol addition. - add better vPHB support to EEH. Daniel Axtens (11): cxl: Convert MMIO read/write macros to inline functions cxl: Drop commands if the PCI channel is not in normal state cxl: Allocate and release the SPA with the AFU cxl: Make IRQ release idempotent cxl: Clean up adapter MMIO unmap path. cxl: Refactor adaptor init/teardown cxl: Refactor AFU init/teardown cxl: Don't remove AFUs/vPHBs in cxl_reset cxl: Allow the kernel to trust that an image won't change on PERST. cxl: EEH support cxl: Add CONFIG_CXL_EEH symbol Documentation/ABI/testing/sysfs-class-cxl | 10 + drivers/misc/cxl/Kconfig | 6 + drivers/misc/cxl/api.c | 7 + drivers/misc/cxl/context.c | 6 +- drivers/misc/cxl/cxl.h | 84 ++++- drivers/misc/cxl/file.c | 19 + drivers/misc/cxl/irq.c | 9 + drivers/misc/cxl/native.c | 104 +++++- drivers/misc/cxl/pci.c | 591 +++++++++++++++++++++++------- drivers/misc/cxl/sysfs.c | 26 ++ drivers/misc/cxl/vphb.c | 34 ++ include/misc/cxl.h | 10 + 12 files changed, 752 insertions(+), 154 deletions(-) -- 2.1.4 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
