[+cc Rafael, Mika, Wong, Hui, Rajat, Keith, LKML, original patch at [5]] On Sat, Oct 05, 2019 at 02:07:56PM +0200, Heiner Kallweit wrote: > +What: /sys/bus/pci/devices/.../link_pm/clkpm > + /sys/bus/pci/devices/.../link_pm/l0s_aspm > + /sys/bus/pci/devices/.../link_pm/l1_aspm > + /sys/bus/pci/devices/.../link_pm/l1_1_aspm > + /sys/bus/pci/devices/.../link_pm/l1_2_aspm > + /sys/bus/pci/devices/.../link_pm/l1_1_pcipm > + /sys/bus/pci/devices/.../link_pm/l1_2_pcipm > +Date: October 2019 > +Contact: Heiner Kallweit <hkallweit1@xxxxxxxxx> > +Description: If ASPM is supported for an endpoint, then these files > + can be used to disable or enable the individual > + power management states. Write y/1/on to enable, > + n/0/off to disable. This is queued up for the v5.5 merge window, so if we want to tweak anything (path names or otherwise), now is the time. I think I might be inclined to change the directory from "link_pm" to "link", e.g., - /sys/bus/pci/devices/0000:00:1c.0/link_pm/clkpm + /sys/bus/pci/devices/0000:00:1c.0/link/clkpm because there are other things that haven't been merged yet that could go in link/ as well: * Mika's "link disable" control [1] * Dilip's link width/speed controls [2,3] The max_link_speed, max_link_width, current_link_speed, current_link_width files could also logically be in link/, although they've already been merged at the top level. Rajat's AER statistics change [4] is also coming. Those stats aren't link-related, so they wouldn't go in link/. The current strawman is an "aer_stats" directory, but I wonder if we should make a more generic directory like "errors" that could be used for both AER and DPC and potentially other error-related things. For example, we could have these link-related things: /sys/.../0000:00:1c.0/link/clkpm # RW ASPM stuff /sys/.../0000:00:1c.0/link/l0s_aspm /sys/.../0000:00:1c.0/link/... /sys/.../0000:00:1c.0/link/disable # RW Mika /sys/.../0000:00:1c.0/link/speed # RW Dilip's control /sys/.../0000:00:1c.0/link/width # RW Dilip's control /sys/.../0000:00:1c.0/link/max_speed # RO possible rework /sys/.../0000:00:1c.0/link/max_width # RO possible rework With these backwards compatibility symlinks: /sys/.../0000:00:1c.0/max_link_speed -> link/max_speed /sys/.../0000:00:1c.0/current_link_speed -> link/speed Rajat's current patch puts the AER stats here at the top level: /sys/.../0000:00:1c.0/aer_stats/fatal_bit4_DLP But maybe we could push them down like this: /sys/.../0000:00:1c.0/errors/aer/stats/unc_04_dlp /sys/.../0000:00:1c.0/errors/aer/stats/unc_26_poison_tlb_blocked /sys/.../0000:00:1c.0/errors/aer/stats/cor_00_rx_err /sys/.../0000:00:1c.0/errors/aer/stats/cor_15_hdr_log_overflow There are some AER-related things we don't have at all today that could go here: /sys/.../0000:00:1c.0/errors/aer/ecrc_gen /sys/.../0000:00:1c.0/errors/aer/ecrc_check /sys/.../0000:00:1c.0/errors/aer/unc_err_status /sys/.../0000:00:1c.0/errors/aer/unc_err_mask /sys/.../0000:00:1c.0/errors/aer/unc_err_sev And we might someday want DPC knobs like this: /sys/.../0000:00:1c.0/errors/dpc/status /sys/.../0000:00:1c.0/errors/dpc/error_source Any thoughts? Bjorn [1] https://lore.kernel.org/r/20190529104942.74991-1-mika.westerberg@xxxxxxxxxxxxxxx [2] https://lore.kernel.org/r/d8574605f8e70f41ce1e88ccfb56b63c8f85e4df.1571638827.git.eswara.kota@xxxxxxxxxxxxxxx [3] https://lore.kernel.org/r/20191030221436.GA261632@xxxxxxxxxx/ [4] https://lore.kernel.org/r/20190827222145.32642-2-rajatja@xxxxxxxxxx [5] https://lore.kernel.org/r/b1c83f8a-9bf6-eac5-82d0-cf5b90128fbf@xxxxxxxxx
