Round 33: USB stack enabled (xHCI + T-PHY + keyboard); payload 35345ec7

2026-08-30 19:29:39 +02:00
parent a252735992
commit 15fa3b22f5
1 changed files with 72 additions and 0 deletions
@@ -1225,3 +1225,75 @@ Still WIP/temporary in the u-boot tree (to revert before upstreaming):
 Next: milestone 4 — distro_bootcmd booting pmOS from USB (sda), then
 cleanup/upstreaming pass (single-purpose commits, MAINTAINERS,
 checkpatch, revert diagnostics).
+
+## Round 33 — USB stack enabled (xHCI + T-PHY + keyboard); payload `35345ec7…`
+
+Milestone 4 step 1: make the pogo keyboard (USB HID behind the GL610
+hub on `usb_host`) work at the prompt. Krane defconfig had been forked
+from pumpkin minus all USB/PHY configs.
+
+### Source survey (all mainline drivers, no new driver needed)
+
+- U-Boot `drivers/usb/host/xhci-mtk.c` binds `mediatek,mtk-xhci`
+  (matches the `usb@11200000` child of `ssusb@11201000`) and expects
+  reg-names `mac` + `ippc` and a `phys` list ON THE XHCI NODE. The
+  upstream mt8183.dtsi models the block for the Linux mtu3 driver:
+  `ippc` (0x11203e00) and the `phys` live on the PARENT mtu3 node,
+  the xhci child has only `mac`. U-Boot has no mtu3 driver.
+  → new `arch/arm/dts/mt8183-kukui-krane-sku176-u-boot.dtsi`
+  (auto-included at the END of the upstream dts by
+  scripts/Makefile.lib `dtsi_include_list`, so `&label` refs work)
+  adds `ippc` to `reg`/`reg-names` and
+  `phys = <&u2port0 PHY_TYPE_USB2>, <&u3port0 PHY_TYPE_USB3>` to
+  `usb_host`. Not a DT fork; upstream file untouched. Verified in the
+  compiled dt.dtb.
+- `drivers/phy/phy-mtk-tphy.c` binds `mediatek,generic-tphy-v2`
+  (mt8183 u3phy node is already status-okay with both ports).
+- Regulators: kukui DT gives `vusb33-supply = <&mt6358_vusb_reg>`, but
+  U-Boot has no MT6358 PMIC/regulator driver. Safe: on missing
+  regulator, `device_get_supply_regulator` fails (debug only) and
+  `regulator_set_enable(NULL)` returns -ENOSYS, which
+  `xhci_mtk_ldos_enable` tolerates (vusb33 is a 3.3 V LDO the firmware
+  already keeps on; no VBUS regulator exists in the DT for usb_host).
+  No PMIC work needed.
+- MMU: MTK armv8-mem-map pre-maps 0x0–0x20000000 as device; xhci
+  (0x11200000), ippc (0x11203e00) and phy (0x11f40000) need NO dynamic
+  mappings — the R31 get_page_table_size headroom is untouched.
+- Enumeration→keyboard path: `U_BOOT_USB_DEVICE(usb_kbd,
+  kbd_id_table)` in common/usb_kbd.c matches HID boot-protocol
+  keyboards during `usb_scan_device`; the bound UCLASS_KEYBOARD probe
+  registers stdio "usbkbd" and re-runs `iomux_doenv(stdin)` when the
+  env `stdin` contains the name.
+- Timing: no `initr_usb` exists in board_r.c anymore — USB is only
+  enumerated on `usb start`. CONFIG_PREBOOT has a built-in default of
+  "usb start" when USB_KEYBOARD=y (boot/Kconfig), so
+  `CONFIG_USE_PREBOOT=y` suffices: preboot runs at main_loop entry
+  (after console_init_r, so probe errors print to the panel/vidconsole;
+  keyboard not yet in the stdin mux at console_init_r is fine —
+  iomux_err falls back to serial, then usb_kbd probe re-muxes stdin).
+  SYS_CONSOLE_ENV_OVERWRITE defaults n, so krane.env's
+  `stdin=serial,usbkbd` survives until the re-mux.
+
+### Changes (u-boot `krane` branch)
+
+- configs/mt8183_kukui_krane_defconfig: USE_PREBOOT, CMD_USB, USB,
+  DM_USB, USB_XHCI_HCD, USB_XHCI_MTK, USB_KEYBOARD, USB_STORAGE (for
+  the sda distro boot), PHY, PHY_MTK_TPHY. Defconfig re-run done.
+- arch/arm/dts/mt8183-kukui-krane-sku176-u-boot.dtsi: new overlay
+  (ippc + phys onto usb_host).
+- board/mediatek/mt8183/krane.env: stdin=serial,usbkbd.
+- Build OK; `_start` still 0x4C001000 == __image_copy_start; dtb
+  verified (mac+ippc+phys on usb@11200000). Payload `35345ec7…`
+  flashed, cmp OK, vbutil_kernel body verification succeeded.
+
+### Decision tree for the reboot
+
+| observation | meaning |
+|---|---|
+| banner → `usb start` scanning lines → prompt; typing works | WORKING |
+| banner → "Scanning bus … failed, error N" or xhci/phy error text, then prompt | enumeration failed at stage N (transcribe the error line) |
+| banner → prompt, no usb lines at all | preboot never ran |
+| reset to menu <1 s after banner | sync abort in USB probe (PANIC_HANG should freeze instead — check it is still set) |
+| prompt but keys do nothing | keyboard not enumerated (pogo not seated?) or stdin mux — re-seat keyboard and power-cycle |
+
+Awaiting user reboot report.