Public bug reported: [Impact] On Dell Pro 5 Micro P5M1260 (RTL8116AF / "RTK 1G OM"), the system cannot enter suspend. Screen turns off, fan stops, power LED goes off, but the system never reaches S0ix: slp_s0_residency stays 0 and package C-state stalls at C10 entry. Hits 100%.
Root cause: RTL8116AF runs in SFP/SerDes mode. The r8169 driver needs a dummy PHY ID so phylib can attach a dummy Realtek PHY driver, with the needed standard PHY registers served through the SerDes register. Also RTL8116AF is a multi-function card: all functions (including hidden functions 2-7) must be put to D3hot and have ASPM enabled so the platform can reach C10 and s0ix. Without these, the PCIe link stays active and blocks package low-power entry. [Fix] Backport Realtek's 5-patch r8169 RTL8116AF series (v1, the smallest set that fixes the issue): net: phy: realtek: add support for dummy phy r8169: move functions forward r8169: fix RTL8116af link readiness bug r8169: add ltr support for RTL8116af r8169: fix RTL8116af can not enter s0idle and c10 These add the dummy PHY, SerDes register handling, LTR/ASPM and multi-function D3hot programming for RTL_GIGA_MAC_VER_52 (RTL8116AF). Because these changes touch RTL_GIGA_MAC_VER_52 broadly, they are gated behind a Dell Pro 5 Micro P5M1260 DMI quirk (a per-device rtl8116af_quirk flag). Only the matched machine takes the new path; other RTL8116AF/VER_52 systems keep the current behavior. Upstream status: not merged into a released kernel yet. Realtek posted a larger phylink-based series (v6, 7 patches) still under review on netdev: https://lore.kernel.org/netdev/[email protected]/ We use the smaller v1 5-patch set as a quirk workaround until that lands. The 5-patch set we carry: https://lore.kernel.org/netdev/[email protected]/ [Test Plan] On Dell Pro 5 Micro P5M1260: 1. Boot the fixed kernel. 2. Trigger suspend: $ sudo rtcwake -m mem -s 20 3. After resume, check S0ix residency: $ sudo cat /sys/kernel/debug/pmc_core/slp_s0_residency_usec (or: sudo turbostat --show=Pkg%LPI,PkgC10 --quiet sleep 1) Without patch: slp_s0_residency stays 0; package never reaches C10/s0ix; system looks suspended (screen/fan/LED off) but never enters S0ix. With patch: slp_s0_residency increments after each suspend; package reaches C10/s0ix. Repeat 20+ cycles to confirm stability. [Where problems could occur] Could break the r8169 driver on RTL8116AF / RTL_GIGA_MAC_VER_52 systems. If the DMI match or the rtl8116af_quirk gating is wrong, the dummy-PHY / SerDes / LTR changes could apply to the wrong device or be skipped on the target, causing: the link not coming up (dummy PHY not attached), wrong link speed reported, or the device failing to reach low-power states on other VER_52 boards. The quirk uses an exact DMI product-name match to keep the blast radius to the single matched Dell machine; any regression is confined to that platform. [Other Info] - Targets: oem-6.17 (Noble) and oem-7.0 (Resolute). - The v1 5-patch set is carried as UBUNTU SAUCE (not upstream). Realtek's proper fix (phylink series) is still under review upstream; the quirk will be dropped once that lands. ** Affects: linux (Ubuntu) Importance: Undecided Status: Invalid ** Affects: linux-oem-6.17 (Ubuntu) Importance: Undecided Status: Invalid ** Affects: linux (Ubuntu Noble) Importance: Undecided Status: Invalid ** Affects: linux-oem-6.17 (Ubuntu Noble) Importance: Undecided Assignee: AceLan Kao (acelankao) Status: In Progress ** Affects: linux (Ubuntu Resolute) Importance: Undecided Assignee: AceLan Kao (acelankao) Status: In Progress ** Affects: linux-oem-6.17 (Ubuntu Resolute) Importance: Undecided Status: Invalid ** Also affects: linux-oem-7.0 (Ubuntu) Importance: Undecided Status: New ** Also affects: linux-oem-6.17 (Ubuntu Noble) Importance: Undecided Status: New ** Also affects: linux-oem-7.0 (Ubuntu Noble) Importance: Undecided Status: New ** Also affects: linux-oem-6.17 (Ubuntu Resolute) Importance: Undecided Status: New ** Also affects: linux-oem-7.0 (Ubuntu Resolute) Importance: Undecided Status: New ** Package changed: linux-oem-7.0 (Ubuntu) => linux (Ubuntu) ** Changed in: linux (Ubuntu Resolute) Status: New => In Progress ** Changed in: linux (Ubuntu Noble) Status: New => Invalid ** Changed in: linux-oem-6.17 (Ubuntu) Status: New => Invalid ** Changed in: linux (Ubuntu) Status: New => Invalid ** Changed in: linux-oem-6.17 (Ubuntu Noble) Status: New => In Progress ** Changed in: linux-oem-6.17 (Ubuntu Resolute) Status: New => Invalid ** Changed in: linux (Ubuntu Resolute) Assignee: (unassigned) => AceLan Kao (acelankao) ** Changed in: linux-oem-6.17 (Ubuntu Noble) Assignee: (unassigned) => AceLan Kao (acelankao) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2160475 Title: System cannot enter s0ix suspend on Dell with RTL8116AF ethernet To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2160475/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
