feat(surface-arm64-audio): Qualcomm LPASS/Q6DSP audio for Surface Laptop 7 (mkosi)

mkosi.profiles/surface-arm64/ADR.md

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+# ADR: Surface ARM64 Snapdragon X Elite - Design Decisions
+
+## 1. Upstream kernel (no linux-surface)
+x1e80100 DTBs (romulus13/15) merged upstream since 6.12.
+linux-surface provides no aarch64 packages.
+Trade-off: camera (MIPI/IPU6) and full audio non-functional until upstreamed.
+Source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom
+
+## 2. SignExpectedPcr=no
+Qualcomm fTPM unavailable during initrd phase -> PCR measurement hang.
+Disk encryption works without PCR binding; policy just less boot-state-tied.
+Source: linux-surface/linux-surface#1590, community testing.
+
+## 3. sbctl firstboot, no MokManager
+Surface NX Mode freezes MokManager at UEFI logo.
+ParticleOS UKI + systemd-boot never touches shim/MokManager.
+sbctl generates keys on firstboot; PK exported for direct UEFI db enrollment.
+Source: https://github.com/linux-surface/linux-surface/issues/1590
+
+## 4. s2idle only (SuspendState=freeze)
+Snapdragon X Elite PSCI/ACPI exposes only s2idle on Linux; S3 unavailable.
+Trade-off: higher suspend battery drain than Windows.

mkosi.profiles/surface-arm64/README.md

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+# Surface ARM64 - Snapdragon X Elite (Surface Laptop 7)
+
+ParticleOS profile for Surface Laptop 7 (x1e80100, arm64).
+Design priorities: bootable images first, TPM enrollment quirks resolved, upstream kernel only.
+See ADR.md for full rationale.
+
+## Hardware status (kernel 6.15+)
+
+| Component | Status | Notes |
+|---|---|---|
+| Boot (systemd-boot + UKI) | Works | Direct UEFI, no shim |
+| CPU (Oryon 12-core) | Works | Full cpufreq |
+| NVMe (PCIe Gen 4) | Works | |
+| Display (eDP 120Hz) | Works | Freedreno/DRM |
+| WiFi (WCN785x/ath12k) | Works | Needs linux-firmware blobs |
+| USB-A / USB-C | Works | USB4/TB limited |
+| Suspend (s2idle) | Works | No S3; higher drain |
+| TPM2 disk encryption | Works | No PCR binding (fTPM quirk) |
+| Secure Boot | Manual setup | See below |
+| Audio | Partial | Windows firmware blobs needed |
+| Camera | Not working | IPU6/MIPI unmerged |
+| Touchscreen | Not working | HID-over-SPI unmerged |
+
+## Build
+
+    mkosi --profile obs-repos --profile desktop --profile gnome --profile surface-arm64 build
+
+Cross-building from x86-64: requires qemu-user-static + binfmt-misc.
+
+## Secure Boot enrollment
+
+1. Disable Secure Boot in Surface UEFI (Volume Up + Power -> Security).
+2. Boot ParticleOS. surface-sb-enroll.service runs on first boot.
+3. cat /var/lib/surface-sb-enroll/ENROLL_SECURE_BOOT.md
+4. Enroll ParticleOS-PK.cer in Surface UEFI.
+5. Re-enable Secure Boot.
+
+MokManager never used. Surface NX Mode freezes it.
+Ref: https://github.com/linux-surface/linux-surface/issues/1590

mkosi.profiles/surface-arm64/mkosi.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Surface Laptop 7 / Snapdragon X Elite (arm64) profile
+# Activate with: mkosi --profile surface-arm64
+#
+# TPM/Secure Boot design notes:
+#  - SignExpectedPcr=no: Qualcomm fTPM unavailable during initrd PCR measurements.
+#    Disabling avoids boot-time hang. Source: linux-surface/issues/1590
+#  - NX Mode quirk: Surface UEFI NX Mode breaks MokManager. Profile uses
+#    UKI + systemd-boot (no shim). Enrollment via sbctl + direct UEFI db.
+#  - Upstream kernel only - bootability over full hardware support.
+
+[Match]
+Profile=surface-arm64
+
+[Distribution]
+Architecture=arm64
+
+[Validation]
+# Inherit SecureBoot=yes from root; override PCR signing (Qualcomm fTPM quirk).
+SignExpectedPcr=no
+
+[Content]
+Packages=
+        qrtr
+        pd-mapper
+        linux-firmware
+        tpm2-tools
+        tpm2-tss
+        sbctl
+        efivar
+        efitools
+
+# Snapdragon X Elite kernel command line
+# clk_ignore_unused/pd_ignore_unused prevent clock/power-domain framework from
+# disabling unattached clocks during init - critical on Qualcomm bringup.
+# Source: Linaro Snapdragon X Elite bring-up documentation
+KernelCommandLine=
+        clk_ignore_unused
+        pd_ignore_unused
+
+# DRM, HID, and TPM CRB modules needed in initrd
+KernelInitrdModules=/drivers/gpu/drm
+                    /drivers/hid/hid-multitouch.ko
+                    /drivers/hid/hid-generic.ko
+                    /drivers/tpm/tpm_crb.ko

mkosi.profiles/surface-arm64/mkosi.conf.d/audio.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Surface Laptop 7 audio DSP additions for Snapdragon X Elite
+# Extends the base surface-arm64 profile.
+
+[Match]
+Profile=surface-arm64
+
+[Content]
+# Qualcomm LPASS/Q6DSP audio stack
+Packages=
+        alsa-utils
+        alsa-ucm-conf
+        pipewire
+        wireplumber
+        pipewire-pulseaudio

mkosi.profiles/surface-arm64/mkosi.conf.d/debian/mkosi.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Debian ARM64 for Snapdragon X Elite.
+# Requires debian unstable for kernel >= 6.12 (x1e80100 DTB support).
+
+[Match]
+Distribution=debian
+Architecture=arm64
+
+[Distribution]
+Release=unstable
+
+[Content]
+Packages=
+        linux-image-arm64
+        linux-headers-arm64
+        firmware-qcom-soc
+        firmware-linux-nonfree
+        tpm2-tools
+        tpm2-abrmd
+        sbctl

mkosi.profiles/surface-arm64/mkosi.conf.d/fedora/mkosi.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Fedora ARM64 for Snapdragon X Elite.
+# Fedora rawhide aarch64 ships x1e80100-microsoft-romulus13/15.dtb since kernel 6.12.
+# Source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/x1e80100-microsoft-romulus13.dts
+
+[Match]
+Distribution=fedora
+Architecture=arm64
+
+[Content]
+Packages=
+        kernel-core
+        kernel-modules
+        kernel-modules-extra
+        qrtr-tools
+        pd-mapper
+        qcom-firmware

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/modprobe.d/surface-arm64-audio.conf

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+# Audio module options for Snapdragon X Elite (Surface Laptop 7)
+# Supplements surface-arm64.conf.
+
+# snd_soc_sc8280xp: Qualcomm LPASS driver family, upstream since kernel 6.11.
+options snd_soc_sc8280xp auto_soc=1
+
+# Q6ASM: Q6 Audio Stream Manager, needed for DSP firmware loading via QRTR.
+options snd_soc_qcom_q6asm debug=0
+
+# HDMI/DP audio via USB4 (Surface Laptop 7 display output)
+install snd_soc_hdmi_codec /sbin/modprobe --ignore-install snd_soc_hdmi_codec && \
+  /sbin/modprobe snd_soc_sc8280xp_common

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/modprobe.d/surface-arm64.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Module options for Snapdragon X Elite (Surface Laptop 7)
+
+# Force CRB interface for Qualcomm fTPM.
+# X Elite fTPM registers as a CRB device; tpm_tis/tpm_tis_spi conflict with it.
+# Source: TCG TPM PC Client Firmware Profile specification
+blacklist tpm_tis
+blacklist tpm_tis_spi
+options tpm_crb force_locality=0
+
+# No PC speaker hardware on Snapdragon
+blacklist pcspkr
+blacklist snd_pcsp
+
+# Increase QRTR socket buffer for Qualcomm subsystem IPC
+options qrtr recv_buf_size=131072

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/surface/sb-enroll.sh

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+#!/bin/bash
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Surface Laptop 7 Secure Boot enrollment helper
+# Source: https://github.com/Foxboron/sbctl
+# Source: https://github.com/linux-surface/linux-surface/issues/1590
+
+set -euo pipefail
+
+INSTRUCTIONS_DIR=/var/lib/surface-sb-enroll
+mkdir -p "$INSTRUCTIONS_DIR"
+
+echo "[surface-sb-enroll] Generating sbctl Secure Boot keys..."
+sbctl create-keys
+
+for uki in /efi/EFI/Linux/*.efi /boot/EFI/Linux/*.efi; do
+  [ -f "$uki" ] || continue
+  echo "[surface-sb-enroll] Signing: $uki"
+  sbctl sign "$uki"
+done
+
+if [ -f /var/lib/sbctl/keys/PK/PK.pem ]; then
+  openssl x509 -in /var/lib/sbctl/keys/PK/PK.pem -outform DER -out "$INSTRUCTIONS_DIR/ParticleOS-PK.cer"
+  echo "[surface-sb-enroll] Platform Key exported: $INSTRUCTIONS_DIR/ParticleOS-PK.cer"
+fi
+
+cat > "$INSTRUCTIONS_DIR/ENROLL_SECURE_BOOT.md" << HEREDOC
+# ParticleOS Secure Boot Enrollment - Surface Laptop 7
+
+Keys generated. To enable Secure Boot:
+
+1. Copy Platform Key to EFI partition:
+   cp /var/lib/surface-sb-enroll/ParticleOS-PK.cer /efi/ParticleOS-PK.cer
+
+2. Enter Surface UEFI: hold Volume Up + Power while powering on.
+
+3. Navigate to Security -> Secure Boot -> disable, then Reset to Setup Mode.
+
+4. Enroll Platform Key from file (select ParticleOS-PK.cer).
+   OR from Linux (SB disabled): sbctl enroll-keys --microsoft
+
+5. Re-enable Secure Boot. Firmware should show Custom Key Configuration.
+
+Verify: bootctl status | grep -i secure && sbctl status
+
+WHY NOT MokManager: Surface NX Mode causes MokManager to hang (black screen).
+ParticleOS uses UKI + systemd-boot with no shim, so MokManager is never invoked.
+Ref: https://github.com/linux-surface/linux-surface/issues/1590
+HEREDOC
+
+echo "[surface-sb-enroll] Done. Read: $INSTRUCTIONS_DIR/ENROLL_SECURE_BOOT.md"

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/systemd/sleep.conf.d/surface-arm64.conf

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Snapdragon X Elite: S3 (deep) not supported. s2idle (freeze) only.
+# Source: Phoronix Surface Laptop 7 Linux coverage
+[Sleep]
+SuspendState=freeze
+SuspendMode=

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/systemd/system-preset/15-particleos-surface-arm64.preset

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+enable qrtr-ns.service
+enable pd-mapper.service
+enable surface-sb-enroll.service

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/systemd/system/pd-mapper.service

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Qualcomm Protection Domain Mapper
+# Needed for WiFi (ath12k) and audio DSP firmware bring-up.
+# Source: https://github.com/andersson/pd-mapper
+
+[Unit]
+Description=Qualcomm Protection Domain Mapper
+After=qrtr-ns.service
+Requires=qrtr-ns.service
+
+[Service]
+Type=simple
+ExecStart=/usr/libexec/pd-mapper
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/systemd/system/qrtr-ns.service

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Qualcomm IPC Router Namespace daemon
+# Required for WiFi (ath12k/WCN785x), audio DSP, modem subsystem IPC.
+# Source: https://github.com/andersson/qrtr
+
+[Unit]
+Description=Qualcomm IPC Router Namespace Daemon
+After=local-fs.target
+Before=network.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/qrtr-ns
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target

mkosi.profiles/surface-arm64/mkosi.extra/usr/lib/systemd/system/surface-sb-enroll.service

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+# SPDX-License-Identifier: LGPL-2.1-or-later
+# Secure Boot enrollment helper - Surface Laptop 7 / Snapdragon X Elite
+#
+# Runs once on first boot. Generates sbctl keys, signs UKIs, writes
+# enrollment instructions. No MokManager - Surface NX Mode firmware
+# freezes when MokManager loads. UKI + systemd-boot needs no shim.
+# Source: https://github.com/linux-surface/linux-surface/issues/1590
+
+[Unit]
+Description=Surface Secure Boot Key Enrollment (First Boot)
+After=local-fs.target
+ConditionFirstBoot=yes
+ConditionPathExists=!/var/lib/sbctl/guid
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/lib/surface/sb-enroll.sh
+
+[Install]
+WantedBy=first-boot-complete.target

mkosi.profiles/surface-arm64/mkosi.extra/usr/share/wireplumber/main.lua.d/91-surface-arm64-qcom.lua

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+-- WirePlumber policy for Qualcomm Q6DSP on Snapdragon X Elite
+-- /usr/share/wireplumber/main.lua.d/91-surface-arm64-qcom.lua
+
+rule = {
+  matches = {
+    { { "node.name", "matches", "alsa_output.platform*sc8280xp*" } },
+  },
+  apply_properties = {
+    ["audio.rate"] = 48000,
+    ["audio.format"] = "S16LE",
+    ["resample.quality"] = 4,
+    ["priority.session"] = 1100,
+  },
+}