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In the future, I would like to extend cxl_test to this core code in order to cover most of the functions in resource.c and the reset mechanism. Do you mind taking a look at if things can be reorganized? I did a quick refactor of your series using LLM [1]. See if the shaping of that is acceptable for you. Essentially I had it organize into 3 parts. drivers/cxl/core/hdm_regs.c, drivers/cxl/core/hdm_state.c, and drivers/pci/cxl.c. Feel free to use any or none of the changes. > > Srirangan, > > Agree with Dave on this point. We should avoid carrying struct pci_dev down > into helpers that don't otherwise need to know about PCI. > > There are a few more examples later in the series where this starts to spread > through the HDM/range handling. I'll call those out on patch 12/16. > > -- Alison > > >> ┌─────┬──────────────────┬───────────────────────────────────────────────┐ >> │ # │ Patch │ Change │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ 1-4 │ unchanged │ Same commit objects, all Reviewed-by tags │ >> │ │ │ kept │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Introduce │ target_or_skip_reg_val replaced by an │ >> │ 5 │ reusable HDM │ endpoint-only settings struct with skip; │ >> │ │ decoder settings │ switch commit takes the target list directly; │ >> │ │ │ endpoints write the DPA Skip registers again │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Move HDM decoder │ New built-in hdm_regs.c, built with │ >> │ 6 │ helpers to │ obj-$(subst m,y,$(CONFIG_CXL_BUS)), so │ >> │ │ built-in code │ linking cxl_core no longer depends on │ >> │ │ │ CONFIG_CXL_RESET │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Share HDM │ Unpacks the common config only; Target List │ >> │ 7 │ decoder register │ and DPA Skip are read where they're used │ >> │ │ unpacking │ again │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Reject │ │ >> │ 8 │ overflowing HDM │ Rebased only │ >> │ │ decoder ranges │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Refresh cached │ Endpoint decoders only; CONFIG_CXL_RESET │ >> │ 9 │ PCI HDM decoder │ introduced here; two bug fixes (below) │ >> │ │ settings │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Cache endpoint │ PCI-side code moved to the new │ >> │ 10 │ HDM state during │ drivers/pci/cxl.c; cache and cxl_rwsem in the │ >> │ │ enumeration │ new built-in hdm_state.c │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ 11 │ Add CXL Device │ Moved to drivers/pci/cxl.c, otherwise │ >> │ │ Reset sequencing │ identical │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Validate and │ │ >> │ 12 │ synchronize HDM │ Region-quiesce API in hdm_state.c, so the PCI │ >> │ │ ranges around │ core never takes cxl_rwsem directly │ >> │ │ reset │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ 13, │ Reject unsafe │ │ >> │ 15 │ scope / Expose │ Rebased only │ >> │ │ CXL Reset │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Restore CXL │ Decoder restore split into hdm_regs.c, which │ >> │ 14 │ state after PCI │ needs no pci_dev │ >> │ │ reset │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> │ │ Restore CXL │ │ >> │ 16 │ state after CXL │ Race fix. Found through testing. │ >> │ │ bus reset │ │ >> ├─────┼──────────────────┼───────────────────────────────────────────────┤ >> >> [1]:https://git.kernel.org/pub/scm/linux/kernel/git/djiang/linux.git/log/? >> h=cxl-type2-reset Hi Alison, Dave, I've adopted the structure from Dave's reference branch in v15: PCI discovery and reset sequencing are in drivers/pci/cxl.c. Generic HDM register and state helpers are in hdm_regs.c and hdm_state.c. v15 series also incorporates the other pieces like cache fixes and decoder refresh during bus-reset restoration from Dave's branch. Thank you for the refactor. -- Regards, Srirangan