espressif: add P4 USB host and Hosted Wi-Fi, fix P4 bring-up

[ladyada-eagleclaw]

Superseded by issue-specific PRs #11492, #11493, #11494, #11495, #11499, #11500, #11501 and #11502. Board definition #11498 remains separate. This branch is retained as the board PR's current integration base.

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AI-assisted with Codex, asked to bring up the Metro ESP32-P4 and separate reusable core support from its board definition. Validation below comes from compiler output, serial captures, and the physical board; no model-generated measurements are used. ## What and why Complete the ESP32-P4 support exercised during Metro bring-up: - Add the existing usb_host.Port API for the P4's dedicated high-speed PHY, alongside a full-speed USB device. Poll TinyUSB's delayed enumeration work so a keyboard can enumerate without a new interrupt. - Restore ROM USB PHY routing when resetting into the downloader; initialize the P4 UID from its factory MAC; correct GPIO49–54 to ADC2 channels 0–5. - Set MIPI DSI output color format explicitly and preserve fractional MHz pixel-clock requests. - Add optional ESP-Hosted Wi-Fi through the standard wifi and socketpool APIs. Boards opt in with CIRCUITPY_ESP_HOSTED and their SDIO wiring. - Allow sdioio and Hosted to share the SDMMC controller: select the actual slot, reserve the Hosted slot, release only the card's slot, and report frequency in Hz. The board definition is the separate dependent PR #11498. No new Python API is introduced. Panel initialization remains in Python. ## SDK dependency The ESP-IDF pin includes two small SDMMC fixes on the existing CircuitPython SDK base: 1. Backport Espressif's controller reinitialization fix, originating at espressif/esp-idf@df53e6a. 2. Serialize interrupt handling with slot removal. A pending DMA interrupt dereferenced a removed slot during repeated card teardown (MCAUSE=5, MTVAL=0x94, in sd_host_get_free_descriptors_count). The fix also dispatches SDIO callbacks to the interrupting slot. Both commits are available from adafruit/esp-idf:metro-p4-sdmmc-reinit. ESP-Hosted is pinned to v2.12.13 and esp-wifi-remote to its recorded upstream commit (component 1.6.5). Dependency fetching uses the existing Espressif CI mechanism. ## Hardware tested Metro ESP32-P4 Rev A, silicon v0.1, 16 MB flash/16 MB PSRAM; Windows; ESP32-C6 running ESP-Hosted 2.12.11; USB keyboard 1c4f:0002; 7-inch Raspberry Pi Touch Display 2; 7,948,206,080-byte SD card. - USB-C CDC/MSC remained available with USB-A keyboard input on the 1280x720 DSI console. Ladyada confirmed typing on the display. NeoPixel colors were checked on the webcam. - All A0–A5 inputs constructed/read; floating readings verify channel access, not voltage accuracy. - Stable UID 6055f9f990fd; unattended ROM entry, verified flashing, and ordinary reboot worked. - RGB888 color bars/text and display release/recreation passed. The 83,330,000 Hz pixel-clock conversion was checked in code, not measured with an instrument. - SD-first startup, 8 MiB patterned file write/read verification at 20 and 40 MHz, 64 buffer offsets with garbage collection, and 24 mount/read/unmount/deinit cycles while Wi-Fi scanned passed. Final read+verify rates were 6.37 and 8.98 MB/s respectively; these include Python verification overhead and are not raw bus benchmarks. - C6 scans found APs; connection, DHCP, gateway ping, DNS, and HTTP 200 passed after a normal reboot. Final safe-mode reason was NONE. Minimal shared-bus exercise (run with an inserted card and compatible C6 firmware): python import board, sdioio, storage, wifi for frequency in (20_000_000, 40_000_000): sd = sdioio.SDCard( clock=board.SD_CLK, command=board.SD_CMD, data=(board.SD_DATA0, board.SD_DATA1, board.SD_DATA2, board.SD_DATA3), frequency=frequency, ) storage.mount(storage.VfsFat(sd), '/sd') print(sd.frequency, sd.count()) storage.umount('/sd') sd.deinit() networks = wifi.radio.start_scanning_networks() print(sum(1 for network in networks)) wifi.radio.stop_scanning_networks() ## Build checks Built against current main (eec31fea92) with make -C ports/espressif BOARD=<board> -j6: - adafruit_p4gpio - espressif_esp32p4_function_ev - espressif_esp32p4x_function_ev - m5stack_tab5 - solderparty_esp32p4_stamp_xl - adafruit_feather_esp32s3_4mbflash_2mbpsram (shared-code regression build) The dependent Metro board also passed with BOARD=adafruit_metro_esp32p4 BUILD=build-metro-p4-c6-final -j4: 1,536,176 bytes used, 560,976 bytes free in the 2 MiB firmware partition. Changed-file pre-commit and git diff --check pass. A separate read-only code audit found no blocking issue; it is not hardware evidence. Hardware evidence is from the integrated development tree; these PRs separate the same board/core changes onto current main. Other boards were compile-tested only. ## Scope BLE, ESP-NOW, camera support, TLS validation, USB hubs and high-speed throughput are not claimed. Other boards are compile-tested only. The first prototype's card-detect fault is a known hardware limitation. This consolidates the unreviewed core work from #11492, #11493, #11494, #11495 and the USB host part of #11496.