Linux's own r8169 through LDLS, deep idle, and the GPU plan

The RTL8168 is now driven by Linux's r8169, unmodified, in a process.
`make ldls-r8169` stages it from the running kernel together with libphy,
mdio-bus, mdio_devres and the Realtek PHY driver, the kernel's BTF and
the RTL PHY firmware, and etc/schinit/ldls-r8169.job starts it at boot
with its log in /var/log/ldls-r8169.log. The native driver is out of the
registry; its code, now with Linux's 8168H setup, stays as the fallback.

LDLS grows what that needed:
- ldlsd loads a comma-separated module set in dependency order, each
  linking against the ones before it, with BTF read before any
  init_module runs;
- a driver core (bus match, driver probe), devres, kernel printf, real
  udelay/msleep/ktime and 1000 Hz jiffies, phylib's bitmaps and
  link_mode_params, firmware from /lib/firmware, and the symbols whose
  stub zero was a lie (list validity, try_module_get, dev_err_probe,
  eth_platform_get_mac_address);
- pdev->bus is a real pci_bus, and cmovcc from per-CPU memory is
  rewritten like the other %gs forms.
In QEMU all five modules load, link and initialise, and r8169 registers
and finds no device. Probe and traffic are untested until real hardware.

The kernel turns ASPM off on Realtek NIC links at boot, as r8169 does
through pci_disable_link_state, which a process cannot.

Idle CPUs enter ACPI _CST's C2 (CC6 on Zen) by port read or MWAIT when
the APIC timer keeps running, instead of only ever halting at C1.

docs/plan/gpu.md: amdgpu and nouveau through LDLS, with measurements.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4

ldls/kpi/kpi.c

@@ -131,6 +131,9 @@ void *
 kpi_find(const char *name)
 {
   int i;
+  for (i = 0; i < kpi_base_count; i++)
+    if (eq(kpi_base_table[i].name, name))
+      return kpi_base_table[i].fn;
   for (i = 0; i < kpi_count; i++)
     if (eq(kpi_table[i].name, name))
       return kpi_table[i].fn;
@@ -512,18 +515,16 @@ static const unsigned char kpi_byte_rev_table[256] = {
 // reads it, re-arms itself against it, and enables the transmitter from
 // inside it, so a stopped clock is a NIC that never transmits.
 //
-// SchOS's uptime() counts 100 Hz ticks, which is a plausible HZ and is the
-// only monotonic source a process has. What matters to a driver is that it
-// advances and never goes backwards; the exact rate matters only to timeouts,
-// and a timeout measured against a slower clock is a longer timeout.
+// It counts at the module's HZ, which is compiled into the module and is 1000
+// on the kernels LDLS loads from -- phylib re-arms its link poll HZ jiffies
+// ahead, and at the 100 Hz this used to count that poll ran every ten seconds.
+// Milliseconds from CLOCK_MONOTONIC; see kpi_jiffies_ms() in base.c.
 unsigned long kpi_jiffies;
 
 unsigned long
 kpi_jiffies_now(void)
 {
-  int t = uptime();
-  if (t > 0)
-    kpi_jiffies = (unsigned long)t;
+  kpi_jiffies = kpi_jiffies_ms();
   return kpi_jiffies;
 }