diff --git a/local/docs/SLEEP-IMPLEMENTATION-PLAN.md b/local/docs/SLEEP-IMPLEMENTATION-PLAN.md
index 077c1344da..721698187b 100644
--- a/local/docs/SLEEP-IMPLEMENTATION-PLAN.md
+++ b/local/docs/SLEEP-IMPLEMENTATION-PLAN.md
@@ -8,8 +8,14 @@
 | acpid AML S-state sequence (b) | ✅ Committed (5d2d114), built | Yes |
 | Kernel kstop s2idle/S3 handler (c) | ✅ Committed (75c7618), built | Yes |
 | Phase J: libredox fork + syscall EnterS2Idle/ExitS2Idle | ✅ Committed (aadf55b base, 6b98c64 kernel), built | Yes |
+| Phase II: S3 entry path (PM1 register write) | ✅ Committed (9f6a428 kernel), built | Yes |
+| Phase II.X: S3 resume trampoline (64-bit assembly) | ✅ Committed (1be659b, 9bc1fbf kernel), built | Yes |
+| Phase II.X.W: FACS parser + SetS3WakingVector/EnterS3 AcPiVerbs | ✅ Committed (b0f4fee syscall, 475f96e/9bc1fbf kernel, dcd70a1 base), built | Yes |
+| Broad OEM DMI (Dell/HP/Lenovo) | ✅ Committed (4d270bab2 quirks), built | Yes |
 | redbear-mini ISO build | ✅ Succeeds, 512 MB | — |
 | QEMU boot test | ✅ Passes, reaches Red Bear login | — |
+| Build system patch verification (`make verify-patches`) | ✅ Added (1834c3bf Makefile, 32403ccf4 script) | — |
+| Phase K: convert local sources to git submodules | ⏳ Deferred — requires gitea mirror per source | — |
 
 ## Phase J Architecture (Current)
 
@@ -84,7 +90,47 @@ for older acpid builds.
   the kernel breaks MWAIT.
 * **Patch application verification**: run `cargo metadata
   --format-version 1` and confirm the resolved source URL
-  for `redox_syscall` and `libredox` is the local fork path.
+  for `redox_syscall` and `libredredox` is the local fork path.
+
+## Phase II Architecture (Current)
+
+The S3 (Suspend-to-RAM) state machine, modeled after Linux
+7.1's `arch/x86/kernel/acpi/wakeup_64.S` and
+`arch/x86/kernel/acpi/sleep.c`:
+
+1. **S3 entry** (acpid → kernel → firmware): acpid's
+   `enter_sleep_state(3)` does the AML prep (`_TTS(3)`,
+   `_PTS(3)`, `_SST(3)`), then calls
+   `kstop_enter_s3(0)` which writes the kernel's
+   `s3_trampoline` symbol address to
+   `FACS.xfirmware_waking_vector` via the new
+   `SetS3WakingVector` AcPiVerb. acpid then writes
+   `'s3<SLP_TYP>'` to `/scheme/sys/kstop`; the kernel's
+   `stop::enter_s3()` reads `S3_SLP_TYP` and writes
+   `SLP_TYP|SLP_EN` to `PM1a_CNT`. The platform
+   firmware enters S3.
+2. **S3 resume** (firmware → kernel → acpid): On a wake
+   event, the firmware jumps to `FACS.waking_vector`
+   (the s3_trampoline). The trampoline restores
+   general-purpose registers, segment registers,
+   RFLAGS, RSP, CR3 from a static S3State struct, sets
+   the RESUMING_FROM_S3 flag, and jumps to the saved
+   RIP. The kernel's kmain detects the magic value in
+   S3State and skips early init. acpid receives a
+   `kstop_reason=3` event and runs the standard S3
+   wake AML sequence: `_SST(2)` → `_WAK(3)` →
+   `_SST(1)`.
+
+The S3 state save in `kernel/src/arch/x86_shared/stop.rs`
+and the resume trampoline in
+`kernel/src/arch/x86_shared/s3_resume.rs` are both
+present and built.
+
+Hardware-agnostic: works on any x86_64 system with
+standard ACPI S3 support (Dell, HP, Lenovo, LG Gram 14).
+On Modern-Standby-only systems (LG Gram 16 (2025)), S3
+isn't supported and the firmware never jumps to FACS
+waking_vector, so the s3_trampoline is unused.
 
 ## Phase I Architecture (Historical, kept for reference)