1 files changed, 12 insertions, 1 deletions

diff --git a/CONTEXT.md b/CONTEXT.md
index 86822d1..fd83245 100644
--- a/CONTEXT.md
+++ b/CONTEXT.md
@@ -259,7 +259,18 @@ Workspace of four crates, all built for the `x86_64-unknown-uefi` target:
   lines (128 chars each, ~16 KB), fed by `serial_println!` (one choke
   point — every boot/low-level message captured for free).  Sequence
   numbers per line + wrap/drop accounting; a dump header reports how
-  many lines were lost to wrap.  Exposed as the `/dev/klog` char
+  many lines were lost to wrap.  Each line carries a `[ssss.mmm]`
+  timestamp — monotonic ms since boot from `interrupts::uptime_ms()`:
+  the 100 Hz PIT tick (10 ms) plus interpolation from the PIT's live
+  1.19 MHz down-counter read twice around the tick load (a jump = a
+  tick fired between reads) for true sub-ms resolution; `TICKS` widened
+  to u64 so uptime never wraps.  **The CMOS RTC cannot provide
+  milliseconds** — it is a 1 Hz BCD device (seconds only) — so the
+  millis come from the PIT.  Early-boot lines are `[0000.000]`
+  (PIT not yet configured; `PIT_READY` gates interpolation), and
+  timestamps are clamped monotonic in the ring.
+
+  Exposed as the `/dev/klog` char
   device; the shell `klog` command is a thin alias for `cat
   /dev/klog` (same filters/redirection), so `klog -t 5`, `klog -g
   fat`, and `klog WRITING /disk/…/boot.log` (persists the boot log)