Xiaomi Pad 6S Pro (hxzbaka)
Xiaomi Pad 6S Pro 12.4 uses shared SM8550 support and board-owned storage, input, firmware and power integration. This record describes implementation coverage and the evidence required for each milestone.
Source record: porting.toml, 0e1f6e52638137db15905db8d775ad73757f39fa.
This page is generated from the device record.
| Area | Status |
|---|---|
| Configuration | implemented |
| Firmware and boot | implemented |
| CPU and interrupts | implemented |
| Memory and DMA | implemented |
| Storage and root | implemented |
| Display | implemented |
| Input | implemented |
| GPU | implemented |
| Network | implemented |
| Audio | implemented |
| Power | implemented |
| Image assembly | implemented |
| Diagnostics | implemented |
Configuration
implemented
Hardware and dependencies
- SM8550 profile, iPadOS 17.7.11 build 21H461, device defconfig, pinned component sources.
Configuration
- board.soc_source = sm8550; board.os_profile = ipados-17.7.11-21H461; schema_version = 2.
- The device owns ShengUfs, ShengHidInput, ShengNovatekTouch and ShengPreflight submodules.
Procedure
- Read https://unixnu.com/porting/device-repository and https://unixnu.com/porting/records.
- Run ./unixnu defconfig sheng_defconfig -D ../UniXNU-sheng from UniXNU.
- Run ./unixnu status --json -D ../UniXNU-sheng and review profiles, components, source pins and patch order.
Development findings
- Tables merge in ARM64, SoC, OS, device order. Arrays replace inherited selections, so include every required component and fragment.
- The selected defconfig applies after the explicit configuration fragments. Keep OS ABI and IPSW pins in the OS profile.
Completion criteria
- All source pins resolve; every selected component has a record; status shows the intended overrides and patch order.
Current limits
- Local overrides can select a different source from the published pin; record the effective source in each verification result.
Next action
- Compare the effective status output whenever a profile, source or component selection changes.
Evidence
Firmware and boot
implemented
Components: ShengPreflight.
Hardware and dependencies
- uefi-sheng firmware, stock firmware DTB, GOP handoff, PSCI SMC interface and vendor firmware inventory.
Configuration
- firmware.dsc = Platforms/Xiaomi/shengPkg/sheng.dsc; firmware.config = sheng.
- proprietary-files.txt records input paths and provenance.
- The firmware DSC and FDF embed UniXNU, UniXNUDxe, DarwinBoot, UniXNURamDiskDxe, DiskIoDxe and FAT support.
Procedure
- Run ./unixnu build firmware -D ../UniXNU-sheng --uefi ../uefi-sheng.
- Record the firmware commit, output FD and handoff memory map before a boot attempt.
- Build the payload, then run ./unixnu bootimg with the firmware DTB. Inspect boot.json ramdisk_bytes and the required firmware modules.
Development findings
- The firmware DTB is an input to boot-image assembly. XNU consumes the separately generated ADT.
- The sheng preflight component belongs with board integration and its firmware requirements.
- The shared UniXNURamDiskDxe reads the Mu-Silicium entry-argument HOB and FDT initrd range to publish the payload block device. ShengBootMemoryDxe owns memory expansion.
- Configured menu entries require a payload FAT filesystem containing EFI/UniXNU/unixnu.toml. Check the UNIXNURAMDISK initrd block-device status when entries are absent.
Completion criteria
- Firmware image builds, enters UniXNU, publishes the framebuffer and preserves the documented memory reservations.
Current limits
- Boot-image assembly requires the selected firmware DTB and proprietary input files.
Next action
- Capture firmware revision and memory reservations with the next image verification.
Evidence
source: Implementation and configuration described in this sectionsource: Shared FDT initrd block-device publication; board memory policy remains in uefi-sheng.
CPU and interrupts
implemented
Components: ArmCpu, ArmDTPlatform.
Hardware and dependencies
- SM8550 CPU affinities, GIC distributor at 0x17100000, redistributors at 0x17180000, 0x40000 stride and 19.2 MHz timer.
- PSCI uses SMC. The board disables cpu1 and cpu2 in its DTS.
Configuration
- dts/sheng.dts includes sm8550.dtsi; shared CPU and interrupt definitions come from the SoC source.
- Kernel arguments select sheng-smp=1 and armcpu-spi-ipi=1.
Procedure
- Compile the board DTS and inspect enabled CPUs, GIC ranges and timer properties in the ADT.
- Record per-CPU entry, timer interrupts and inter-processor interrupt delivery.
Development findings
- CPU affinity values are hardware identifiers. Enabled CPU count and MPIDR affinities must be checked together.
- GIC register ranges must use translated physical addresses from the hardware tree.
Completion criteria
- Every enabled CPU reaches its entry checkpoint and timer/IPI handling works on each enabled CPU.
Current limits
- CPU selection and frequency policy are board inputs; SoC topology describes all cores.
Next action
- Attach per-CPU and interrupt observations for the selected firmware and image.
Evidence
Memory and DMA
implemented
Hardware and dependencies
- Handoff DRAM at 0x80000000 with size 0x80000000; splash reservation at 0xb8000000 with size 0x2b00000.
- Payload owned-memory request is 0x130000000. Device DMA requires controller stream IDs, address widths and ownership.
Configuration
- device_tree.source = device:dts/sheng.dts; include_dirs = [soc:dts].
- payload.adt.owned_memory_size and firmware reservations describe separate allocations.
Procedure
- Compare firmware RAM ranges, reserved regions, DTS ranges and ADT memory-map entries.
- Check DMA buffers against controller address width, cache policy and SMMU mapping before submitting work.
Development findings
- Physical register translation and CPU virtual mappings have different purposes. Preserve physical resource ranges in hardware descriptions.
- GPU and UFS use different SMMU instances and stream assignments.
Completion criteria
- All handoff regions are accounted for and each enabled DMA engine accesses its allocated range with the documented cache policy.
Current limits
- The DTS declares the current handoff window and splash region; memory sizing requires the selected firmware map.
Next action
- Record the firmware memory map and each DMA consumer when changing reserved memory.
Evidence
Storage and root
implemented
Components: ShengUfs, VirtioMmioBlock, RamBlock, VerifiedRoot.
Hardware and dependencies
- UFS host 0x01d84000/0x3000; PHY 0x01d80000/0x2000; GCC base 0x00100000.
- GCC AXI, AHB, UniPro, symbol and PHY auxiliary branches; power domains and firmware link state.
- Apps SMMU at 0x15000000, UFS stream 0x60, context-bank ownership, DMA width and cache maintenance.
- LUN 0 uses 4096-byte blocks; userdata spans LBAs 3094592 through 64007162.
Configuration
- Select ShengUfs and CONFIG_XNU_NATIVE_UFS=y; native-ufs-root=1 enables the root path.
- userdata defines OS and SystemOS windows. payload.adt.root_match_volume_uuid = 04769D26-2CA0-4825-B443-E2E5F88300F2.
Procedure
- Read https://unixnu.com/porting/ufs with this storage record.
- Inspect clock enables, power state, HCE/HCS, link state, request-list base and SMMU mappings before changing controller ownership.
- Validate SCSI capacity and GPT reads, then publish root windows and mount the configured root UUID.
- Verify persistent Data writes on the documented Data allocation with a recovery image available.
Development findings
- An idle AHB branch may report CLK_OFF with hardware gating enabled. Check enable and gating bits together.
- SMMU bypass still has address-width constraints. Validate every DMA range and context-bank assignment.
- ShengUfs contains controller access, GPT/window parsing and sheng Data/log policy. Reuse each layer according to its inputs.
Completion criteria
- Host: register, clock, link and SMMU facts match the board inventory.
- Reads: SCSI capacity, GPT and known blocks are correct; OS/SystemOS windows stay within userdata.
- Root: the configured volume mounts and launchd starts. Persistence: writes survive reboot within the allocated Data region.
Current limits
- The SoC DTSI exports host and PHY ranges. GCC and UFS SMMU handling currently use constants and operations in ShengUfs.
- The root transport uses a polled request slot. Its firmware adoption path requires a usable existing request list.
Next action
- Record clock/PHY/reset initialization ownership and the SMMU stream before adapting this driver to another board.
Evidence
Display
implemented
Components: GopFramebuffer.
Hardware and dependencies
- UEFI GOP framebuffer, stride, pixel format, splash reservation and board panel/backlight controls.
Configuration
- Select GopFramebuffer; CONFIG_XNU_NATIVE_LEGACY_DISPLAY=y; artwork-display-gamut = sRGB.
- sheng-vsync=120 requests board display timing.
Procedure
- Verify GOP address, dimensions, stride and pixel layout before enabling presentation.
- Build the late display archive with the selected OS ABI records, then check display publication and frame presentation.
Development findings
- The display source and ABI binding are selected independently from the physical panel configuration.
- The board configuration declares sRGB for the current 8-bit framebuffer path.
- scripts/build-gop-legacy-display.py also builds the board driver objects in the display archive, including the ADSP, IPC router, FAT reader and battery manager.
Completion criteria
- A known frame appears with correct geometry and colors, then userland presentation and backlight controls work.
Current limits
- The late display builder needs qualified prelink candidates and ABI records. A timing request requires a measured presentation result.
Next action
- Record frame timing, pixel format and presentation evidence for each image used to qualify display.
Evidence
Input
implemented
Components: ShengHidInput, ShengNovatekTouch, QcomGeniSpi.
Hardware and dependencies
- Novatek NT36532 sensor, GENI SPI controller, pin configuration, reset/interrupt lines, firmware and touch coordinate geometry.
Configuration
- Select ShengHidInput, ShengNovatekTouch and QcomGeniSpi; sheng-touch=4 and sheng-touch-hid=1 select board integration.
Procedure
- Read TouchBoard.h and verify the SPI clock and mode against the controller setup.
- Validate protocol reports, contact tracking and coordinate orientation before publishing HID events.
Development findings
- Controller transfer logic, sensor protocol and board sensor geometry are separate inputs.
- Track contact IDs across movement and lift events; a register read alone covers only transport access.
Completion criteria
- Touches map to the display, simultaneous contacts keep stable IDs, release events arrive, and buttons produce expected HID reports.
Current limits
- Sensor firmware and board dimensions remain sheng inputs.
Next action
- Attach contact and orientation observations when firmware or geometry changes.
Evidence
GPU
implemented
Components: Adreno740, AdrenoMetal, AirNir, Sm8550Platform, AdrenoPM4, AdrenoFirmware, ArmSmmu4K.
Hardware and dependencies
- A740 GPU/GMU registers, GPU SMMU streams 0/1 and GMU stream 5, signed ZAP firmware and board power votes.
- Turnip, metal2vulkan, AIR translation and the selected OS GPU/Metal ABI.
Configuration
- Select Adreno740, AdrenoMetal and AirNir; shared SM8550 operations arrive through component dependencies.
- Board scripts combine shared GMU code with package/ShengGmuVotes.c.
Procedure
- Qualify power, firmware, SMMU and GMU startup before command submission.
- Check memory mapping, command completion and a known rendered image before staging the Metal plugin.
Development findings
- GPU generation and the frontend ABI define component scope. Firmware, votes and display integration remain board inputs.
- Shared platform code and board votes require separate include paths during archive assembly.
Completion criteria
- GPU submissions complete, mapping/fence handling is correct, a known image renders, and the selected Metal client presents it.
Current limits
- A740 coverage depends on the selected firmware and OS ABI; board qualification requires its own memory and power evidence.
Next action
- Record the exact firmware, compiler inputs, driver revision and rendered output for the next qualification.
Evidence
Network
implemented
Components: Ath12kWifi.
Hardware and dependencies
- Ath12k device on PCIe, BAR windows, MSI routing, DMA callbacks, firmware, MHI and QRTR services.
Configuration
- Select Ath12kWifi. build-gop-legacy-display.py compiles its objects through build-ath12k-wifi.py.
Procedure
- Verify PCIe enumeration and MSI delivery before MHI startup.
- Record firmware startup, scan, association, address configuration and bidirectional packet delivery separately.
Development findings
- The reusable Wi-Fi stack consumes board callbacks; PCIe and the OS network interface are owned by the device integration.
- MHI startup and network traffic are separate completion points.
Completion criteria
- Scanning, association, address configuration and sustained receive/transmit traffic pass with the selected firmware.
Current limits
- The source implements the station path through WifiNet.cpp and board PCIe integration. Device evidence must identify the firmware and access point.
Next action
- Attach association and receive/transmit observations for the current firmware and image.
Evidence
Audio
implemented
Hardware and dependencies
- ADSP firmware, SMEM, SMP2P, GLINK, GPR services, board codec and audio routing.
Configuration
- The board display archive includes ADSP and audio probe objects.
Procedure
- Check firmware loading and ADSP service readiness before configuring audio endpoints.
- Record route, format and playback/capture observations for each enabled endpoint.
Development findings
- The ADSP image loads in place from the split adsp and adsp_dtb files in /image of the modem_a FAT volume (modem_b as fallback); sheng-adsp-fw=DIR reads adsp.mbn and adsp_dtb.mbn from DIR instead.
- The DSP reaches GLINK and opens the battery manager and IPCRTR channels. The IPC router answers the DSP's service locator requests.
- Firmware startup, service registration and audible playback require separate evidence.
- The GPR client and firmware loading helpers can be inspected independently from codec routing.
Completion criteria
- Each declared route carries the selected audio format through playback or capture and handles start/stop correctly.
Current limits
- Current source contains ADSP bring-up and audio framework probes. Endpoint playback qualification needs route-specific evidence.
Next action
- Document the codec, clocks and endpoint routing before claiming playback completion.
Evidence
Power
implemented
Components: AppleKeyStoreState.
Hardware and dependencies
- Board PMGR integration, clocks/regulators and per-peripheral power requirements.
- ADSP battery manager: PMIC GLINK owner 32778 on PMIC_RTR_ADSP_APPS; board properties use opcode 0x50; fuel gauges 0x8a/0x8b and 0xa6/0xa7.
Configuration
- CONFIG_XNU_SHENG_PMGR=y; sheng-pmgr=2 selects the board integration.
- AppleKeyStoreState is selected with the OS event integration.
- sheng-adsp=2 sheng-battery=1 publish the battery as an IOPMPowerSource.
- sheng-usb-sdp-ma sets the input limit on a standard computer port (default 900; 0 keeps the firmware limit).
Procedure
- Document each clock, regulator and firmware-owned state before enabling power transitions.
- Check battery units and update behavior separately from suspend/resume and peripheral power.
- Read the [battery], [battery-raw] and [charger] log lines with scripts/read-sheng-log.py.
Development findings
- The ADSP firmware runs charging and PD/PPS negotiation without host requests.
- Battery properties after 11 are shifted by one: charge current 12, temperature 13, charge counter 15, cycles 16, design 17, full 18, time to full 20, time to empty 21.
- Charge is the sum of both fuel gauges' remaining over full capacity. Battery current is reported discharge-positive.
- USB property 6 reads SDP on every port. Property 7 carries the adapter type (6 PD, 8 PD PPS).
- A PPS adapter gets a 3 A input limit at about 8.7 V; the battery charges at the 2000 mA charge current with the charge pump off.
- Both cells and the PD adapter read unauthenticated.
- A Mac USB-C port negotiates PD 5 V with a 1.2 A input limit, below the load during boot.
- Power policy belongs to the board even when controller operations are shared.
Completion criteria
- Declared power controls and battery readings match observations; each claimed sleep/resume transition restores its dependent peripherals.
Current limits
- Adapter details shown to iOS come from USB property 6, so every adapter reads as a computer port.
- Charge current stays at 2 A without fuel gauge and adapter authentication.
- A low-battery shutdown panics in vnode_rele_ext during unmount.
- Per-peripheral controls and battery publication have separate coverage from system suspend.
Next action
- Take adapter details from property 7.
- Authenticate both fuel gauges, then qualify PPS charge pump charging; Xiaomi adapter authentication follows.
Evidence
source: Implementation and configuration described in this sectionhost: PASS battery manager: 4074 checks Command:python3 scripts/check-battery-host.py. Revision:8719a19294bc79eed72366a19070acfd8e131737.device: PPS adapter: 8.72 V at 1.3 A in, battery +1.99 A, 1 to 3 percent in 3 minutes. Mac: PD 5 V, 1.2 A limit, battery -0.9 to -1.2 A. Temperature 31.4 to 32.9 C; full 9353 mAh, design 9800 mAh, 172 cycles. Command:fastboot boot boot.img; python3 scripts/read-sheng-log.py --wait 240. Revision:8719a19294bc79eed72366a19070acfd8e131737.
Image assembly
implemented
Components: DarwinBoot, XnuPrelink, SoftwareAES.
Hardware and dependencies
- Prelinked kernel, hardware DTB, generated ADT, trust cache, Data seed, platform identity and firmware DTB.
Configuration
- Payload volume is 208 MiB. kernel.patch_series selects ARM64, SoC, OS and device series in order.
Procedure
- Build kernel and package, then payload with --unique-chip-id and the selected trust-cache/Data inputs.
- Run ./unixnu bootimg -D ../UniXNU-sheng --uefi ../uefi-sheng --dtb <firmware.dtb> and inspect the assembly report.
Development findings
- The OS boot-progress integration follows the SoC hooks in patch order.
- The payload carries kernel.macho.adt; the boot image carries the firmware FDT. Keep the two inputs named explicitly.
Completion criteria
- Kernel and prelink succeed, payload contains all declared inputs, and the boot image matches the bootloader format and size limit.
Current limits
- Image output depends on the selected ABI audits, firmware and volume policy inputs.
Next action
- Attach artifact paths and exact source revisions to the next image build record.
Evidence
Diagnostics
implemented
Hardware and dependencies
- Serial or framebuffer diagnostics, panic region, boot checkpoints and a recovery path.
Configuration
- boot-progress=2 enables checkpoints; source and image revisions accompany every log.
Procedure
- Run the existing check for the changed area and keep its command, output and input revision.
- Record the last completed checkpoint and the first failing operation; link the captured output.
Development findings
- A source implementation, a host check and a device observation establish different completion levels.
- Keep an unresolved cause explicit and record the next measurement that can distinguish it.
- The UFS log carries [adsp], [qrtr], [battery], [battery-raw] and [charger] lines for the DSP, the IPC router and the charger.
- Host checks for the ADSP path: check-adsp-host.py, check-modem-fw-host.py, check-qrtr-host.py and check-battery-host.py.
Completion criteria
- Each claimed milestone has a reproducible command, a matching source/image revision and an accessible result.
Current limits
- Source references in this record describe implemented behavior. Host and device status require their respective evidence entries.
Next action
- Add captured host or device evidence when repeating a checkpoint on a known image.