Miyoo Flip — Device Wiki & Reference

This repository is the maintained wiki and reference for the Miyoo Flip handheld (Rockchip RK3566) on mainline Linux. The documentation is kept up to date as the canonical device reference.

For a working image and current code (DTS, drivers, ROCKNIX build system), use Zetarancio/distribution (branch flip). GitHub Actions produces two images (specific and generic); use the specific one for testing. This main branch is wiki-first. Legacy build scripts are kept in branch buildroot.

Wiki updated to: e78fefa on the flip branch (2026-03-20).

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Hardware

Component	Detail
SoC	Rockchip RK3566 (quad Cortex-A55 @ 1.8 GHz)
GPU	Mali-G52 2EE (Bifrost)
RAM	LPDDR4
Storage	SPI NAND 128 MB + 2x MicroSD
Display	LMY35120-20p (marking 2503x). Confirmed: 640×480 MIPI DSI, 2-lane, RGB888 video mode (stock DTS). Presumed: FT8006M COG — details
WiFi/BT	RTL8733BU (USB)
Audio	RK817 codec + speaker amplifier
PMIC	RK817 (main) + VDD_CPU (TCS4525 @ 0x1c and/or RK8600 @ 0x40 — see note below)
Battery	Miyoo 755060, 3.7 V nominal, 3000 mAh, 11.1 Wh (typical pack marking)
UART	ttyS2 @ 1,500,000 baud (3.3V)

VDD_CPU / I2C0: 2025 stock DTS and the current flip DTS enable both CPU-regulator nodes (status = "okay"), matching stock behavior (b7525be, 6882112). Two board revisions (one populated at 0x1c or 0x40) are suggested by firmware but not proven on hardware. The kernel probes both; the absent chip returns probe failure and is ignored—the present rail works and the system boots normally.

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Documentation

Full index → docs/README.md

Topic	Front page	Subpages
Boot and flash	boot-and-flash.md — specs, images, boot chain	Flashing, Boot from SD
RK3566 reference	rk3566-reference.md — SoC overview	Datasheet, TRM 1, TRM 2, Unused pins
Stock firmware	stock-firmware-and-findings.md — dumps, overview	BSP/DDR findings, SPI/boot chain
Drivers and DTS	drivers-and-dts.md — DTS evolution, drivers	Board DTS, Drivers, DTS porting, Display, WiFi power-off, Suspend
Troubleshooting	troubleshooting.md	—
Serial	serial.md	—

Reference boot logs in this repo: boot_log_ROCKNIX.txt (mainline; DMC after resume, power-down reaches reboot: Power down); boot_log_STOCK_INCLUDE_SLEEP_POWEROFF_AND_DEBUG.txt (stock with DDR/sleep debug); boot_log_STOCK_INCLUDE_SLEEP_POWEROFF.txt (stock, sleep/poweroff).

Note: boot_log_ROCKNIX.txt may not match the latest kernel/DTS iteration at all times; it is kept as historical proof of a working mainline capture (e.g. DMC after resume, power-down), not as a live regression log.

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Status

Subsystem	Status	Notes
Boot (U-Boot + kernel)	Working	Mainline 6.18+, SPI NAND or SD
Display (DSI panel)	Working	640x480, panel driver
Backlight	Working	PWM4
Audio (RK817)	Working	simple-audio-card, speaker amp
WiFi (RTL8733BU)	Working	Out-of-tree 8733bu, 6.18+. Optionally a separate driver can shut down the combo at GPIO level when both radios are off; see WiFi/BT power-off.
Bluetooth	Working	Unified firmware, btusb re-probe
GPU (Mali-G52)	Working	mali_kbase + libmali, 200–800 MHz
Storage	Working	SPI NAND MTD, both SD slots
HDMI	Working	Video and audio (when enabled in DTS)
HDMI audio	Working	With HDMI output
DMC (DDR devfreq)	Working (out-of-tree)	Scaling + resume confirmed; see BSP and DDR findings, SPI and boot chain
VPU / RGA	Working	hantro-vpu, rockchip-rga
IEP	Not working	BSP-only (MPP)
Suspend	Working (out-of-tree)	Requires rk3568-suspend and patched rk817 core available at Zetarancio/distribution for BL31 deep sleep; see Suspend and vdd_logic
Input (buttons + rumble)	Working	17 GPIO buttons, joypad, rumble (PWM5)

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Key Discoveries

Findings that made mainline work on this device (details in the wiki).

• VSEL register hang: The BSP DTS uses rockchip,suspend-voltage-selector but mainline fan53555 reads fcs,suspend-voltage-selector. Wrong name causes VDD_CPU to drop and the board to hang immediately after "FAN53555 Detected!" on kernels 6.4+.

• DSI panel init in command mode: The stock driver sends init commands via a DT property. On mainline, commands must be sent during prepare() (command mode), not enable() (video mode), or they collide with the video stream on the shared FIFO.

• PMIC dependency cycles: vcc9-supply = <&dcdc_boost> and sleep pinctrl states create circular dependencies that fw_devlink cannot resolve. Fixed by using <&vccsys> and removing sleep pinctrl on RK817. You can then reuse sleep pinctrl + patched rk817 core available at Zetarancio/distribution.

• DDR on mainline: The BSP DMC uses Rockchip V2 SIP (shared memory + MCU/IRQ). An out-of-tree DMC devfreq driver implements this for mainline 6.18+ and is confirmed working; see BSP and DDR findings and SPI and boot chain.

• Suspend: Out-of-tree rk3568-suspend (not rk356x) configures BL31 deep sleep; required for vdd_logic off-in-suspend. See Suspend and vdd_logic.

• WiFi/BT full poweroff: The 8733bu driver only does software rfkill; it does not control the power-enable GPIO. Full hardware poweroff of the combo requires a separate driver that controls the enable GPIO and integrates with rfkill. See WiFi/BT power-off.

• Boot chain: Any U-Boot for this board must include OP-TEE (BL31) in the FIT image; the boot chain expects ATF + OP-TEE + U-Boot. Bootrom/SPL behaviour for SD boot is documented in Boot and flash and SPI and boot chain.

• Full power-off: Do not set system-power-controller for now on the RK817 PMIC. It races with PSCI SYSTEM_OFF and leaves the PMIC partially on (battery drain). Without it, rk8xx_shutdown() sets SLPPIN_DN_FUN and BL31 powers down cleanly. See Troubleshooting and Zetarancio/distribution@0a2f831. Old stock software was not setting system-power-controller, newest reintroduced it, may work in conjunction with patched rk817 core.

• 2025 stock alignment: PMIC suspend/resume, battery OCV (descending table), shared SD vqmmc, DMC devfreq tuning, and DSI/panel init have been refined against newer stock; see Stock firmware and findings and Board DTS / PMIC / DDR. Commit history: distribution flip.

• VDD_CPU / I2C0: Same story as the Hardware table note; full write-up: Board DTS — I2C0 CPU regulator (b7525be, 6882112).

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Project structure

docs/                          Documentation wiki (maintained)
miyoo355_fw_20250509213001/    Unpacked 2025 stock card image (DTS, rootfs) — see docs/stock-firmware-and-findings.md
spi_20241119160817/            Unpacked 2024 SPI dump (DTS, rootfs, joystick study used to improve the rocknix driver) — see docs/stock-firmware-and-findings.md
boot_log_ROCKNIX.txt           Mainline boot log (historical proof; may not match latest build—see note below)
boot_log_STOCK_INCLUDE_SLEEP_POWEROFF_AND_DEBUG.txt   Stock with DDR/sleep debug
boot_log_STOCK_INCLUDE_SLEEP_POWEROFF.txt             Stock, sleep/poweroff capture

Wiki: The docs/ tree is the device wiki and is maintained.

Boot logs: In repo root — boot_log_ROCKNIX.txt (mainline capture; not guaranteed current with the latest DTS/kernel—kept as proof); boot_log_STOCK_INCLUDE_SLEEP_POWEROFF_AND_DEBUG.txt (stock + debug); boot_log_STOCK_INCLUDE_SLEEP_POWEROFF.txt (stock).

Build system: For current builds and images use Zetarancio/distribution. This main branch is documentation-focused; legacy local build scripts live on branch buildroot. Flashing steps are in docs/boot-and-flash/flashing.md.

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Quick start

For a current image and build, use the Zetarancio/distribution (ROCKNIX, branch flip) repo.

For legacy local build scripts, see branch buildroot.

For flashing and SD boot on this wiki, see Boot and flash.

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External references

Datasheets & TRM (Rockchip)

Document	URL
RK3566 Datasheet V1.2	FriendlyElec wiki
RK3568 TRM Part 1	Radxa
RK3568 TRM Part 2	Radxa

steward-fu’s Miyoo Flip pages

Topic	URL
UART	miyoo_flip_uart.htm
Specs	miyoo_flip_spec.htm
Pin mapping	miyoo_flip_pin.htm
MTD	miyoo_flip_mtd.htm

• Release (many useful files): steward-fu/website — miyoo-flip — toolchain, U-Boot, xrock, SPI dumps, firmware, etc.

Related projects

• Zetarancio/distribution — Current ROCKNIX Miyoo Flip (branch flip)
• ROCKNIX
• GammaOS Core

Other reference

• Rosa1337/rk3568_linux

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License

Documentation and scripts: GNU GPL v2. DTS/patches follow kernel GPL v2. Third-party components have their own licenses.

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Thanks

Thanks to steward-fu for the Miyoo Flip resource site and assets; beebono, sydarn, and the community behind SpruceOS for their work and support. This project wouldn’t be where it is without them.