jetson-derive-carrier

Customize first-run gate for any

customize-*

skill on a custom carrier. Resolve the active target per

target-platform-contract.md

. Refuse if no

custom_carrier:

block, or if

<source.root_path>/Linux_for_Tegra/.git

is missing (

jetson-init-source

first). Template file create/copy rows land in a single overlay-tracker commit and copy directly to the custom-carrier-renamed target path — reference-named pristine files are never staged (see Fork plan for the local rule, which overrides the standard pristine + customization split from the workflow); conf-chain discovery follows per-board conf dispatch. Kernel base DTB is not forked — carrier deltas layer as a DT overlay wired via

OVERLAY_DTB_FILE

Identifiers (from active profile):

<chip>

from

reference_devkit.module.id

via catalogue (unknown → warn, fallback

tegra234

);

<module-id>

<module-sku>

from

reference_devkit.module

;

<carrier-id>

<carrier-sku>

from

reference_devkit.carrier

;

<custom-id>

<custom-sku>

<custom-flash-conf>

from

custom_carrier

<real-conf>

readlink <bsp_image.root_path>/Linux_for_Tegra/<reference_devkit.flash_config>

(NVIDIA convention

<devkit>.conf

→

<carrier>-<module>-a<rev>.conf

; warn + treat top-level as real + skip symlink-wrapper row if not a symlink).

<custom-id>

is a custom carrier board token, not necessarily an NVIDIA-style

pNNNN

ID. Use it verbatim in dash-form filenames and DT compatible strings. When a target file family uses p-stripped numeric tokens, derive

<custom-id-file-token>

NNNN

only if

<custom-id>

matches

^p[0-9]{4}$

; otherwise use

<custom-id>

unchanged. Do not reject custom carrier IDs merely because they do not start with

Instructions

The fork plan below is the instruction set: one discovery pass, then a row-by-row fork of the per-board fileset, gated by the commit-message preview before each

git commit

Fork plan

Every

git commit

produced by this skill — in the overlay tracker (

Linux_for_Tegra/

) or the

hardware/

source repo — runs through the commit message preview gate. Surface the staged file list + proposed message to the operator and require accept / edit / cancel before each

git commit

; on cancel leave the index staged for manual resolution.

Materialize renamed forks even when bytes do not change. For every accepted fork-plan row, create and track the custom-carrier target path; do not skip a missing target because the fork is only a rename/copy or is byte-identical to the reference. This includes BCT forks such as pinmux, GPIO/GPIOINT, padvoltage/PMC, misc, and MB2 misc. Skip only when the Acceptance column allows it, the source is an explicit warn-and-skip miss, or the expected target path is already tracked; in the last case, report it as already derived and do not create an empty commit.

Template file create/copy rows squash into one overlay-tracker commit, and reference-named pristine files are never staged. All rows that materialize a new (template-derived) file in the overlay tracker — board flash-conf, flash-conf symlink, MB1 BCT (pinmux, GPIO/GPIOINT, padvoltage/PMC, misc), MB2 BCT (misc), BPMP DTB (when opted in), nvpmodel, nvfancontrol — copy directly from

<bsp_image.root_path>/Linux_for_Tegra/<rel>/<reference-name>

<source.root_path>/Linux_for_Tegra/<rel>/<custom-name>

with any content edits applied before staging. The reference-named (

<carrier-id>-<carrier-sku>

-keyed) filename is never staged or committed in the overlay tracker — only the custom-carrier-renamed file is tracked. This overrides the standard pristine + customization split from commit batching. All such rows land in a single overlay-tracker commit that adds: (i) the custom-carrier-named files at their target paths with content already applied, (ii) the flash-conf symlink, and (iii) the targeted flash-conf content rewrites inside the renamed flash-conf for

PINMUX_CONFIG

GPIO_CONFIG

GPIOINT_CONFIG

PMC_CONFIG

MISC_CONFIG

MB2_BCT

(plus

BPFDTB_FILE

when BPMP DTB is opted in). Rows that edit existing upstream files instead of creating templates — the

nvpower.sh

patch — and the overlay wire-up (

OVERLAY_DTB_FILE+=

append to the just-created flash-conf fork, treated as a temporally distinct phase per commit batching) remain separate commits per their own rows. The DT overlay skeleton commits in

bsp_sources/hardware/

, not the overlay tracker, so it is unaffected. The commit message preview gate fires once on the squashed commit; warn-and-skipped rows do not contribute, and if every row in the bundle is already tracked the commit is omitted entirely.

Discovery (single batched pass)

Run one discovery pass; do not interleave with staging. Do not truncate listings — every candidate filename in each scanned directory must be visible to the matcher.

head

tail

| head -N

| tail -N

, and any other row-limiting filter are out of bounds for this step; use

ls -1

find

unclipped, or grep on the full output. Truncating risks false warn-and-skip calls when the matching file sits past the cutoff. Capture:

Flash-conf vars:
```
DTB_FILE
```
/
```
TBCDTB_FILE
```
/
```
BPFDTB_FILE
```
/
```
PINMUX_CONFIG
```
/
```
PMC_CONFIG
```
/
```
GPIO_CONFIG
```
/
```
GPIOINT_CONFIG
```
.
```
DTB_FILE
```
/
```
TBCDTB_FILE
```
are captured for reference only so the overlay wire-up can derive
```
<dtb-stem>
```
for the overlay filename — they are never rewritten by this skill.
BCT
```
.dts
```
at
```
bootloader/generic/BCT/
```
;
```
.dtsi
```
siblings live one level up at
bootloader/
— NOT alongside.

nvpmodel:

nvpmodel_<module-id>_<module-sku>*.conf

. nvfancontrol:

nvfancontrol_<module-id>_<module-sku>_<carrier-id>_<carrier-sku>.conf

```
nvpower.sh
```
anchors for (a)–(d):
```
<carrier-id>
```
cvb branch,
```
<module-id>-<module-sku>
```
SKU
```
elif
```
,
```
tegra<chip>
```
nvpmodel cascade,
```
tegra<chip>
```
nvfancontrol cascade.

File / category	Discovery	Acceptance	Fork rule
Board flash conf	`<real-conf>`	Always	Filename sub `<carrier-id>-<carrier-sku>` → `<custom-id>-<custom-sku>` . Content sub is targeted, not blanket: rewrite RHS only for vars whose file this skill forks — `PINMUX_CONFIG` , `PMC_CONFIG` , `GPIO_CONFIG` / `GPIOINT_CONFIG` , `MISC_CONFIG` , `MB2_BCT` . Other carrier-keyed vars ( `DTB_FILE` , `TBCDTB_FILE` , `SCR_CONFIG` , `PMIC_CONFIG` , `DEVICEPROD_CONFIG` , `PROD_CONFIG` , `MINRATCHET_CONFIG` , `UPHY_CONFIG` , dynamic `OVERLAY_DTB_FILE+=` ) MUST stay at reference values — their files aren't forked here and a blanket `sed` would point them at nonexistent files. `DTB_FILE` / `TBCDTB_FILE` specifically: base DTB is not forked; the overlay row appends a new `OVERLAY_DTB_FILE+=` line instead. `BPFDTB_FILE` : opt-in extra commit. Never touch `<chip>` , `<module-id>` , `xxxx` .
Flash-conf symlink	Unconditional	Always (skip if `<real-conf>` not a symlink)	New symlink `<custom-flash-conf>` → flash-conf fork
MB1 BCT pinmux	`PINMUX_CONFIG` + `#include` follow ¶	Always	Rename rule †
MB1 BCT GPIO	`GPIO_CONFIG` / `GPIOINT_CONFIG` + `#include` follow ¶	Always	Rename rule †
MB1 BCT padvoltage	`PMC_CONFIG` + `#include` follow ¶	Always	Rename rule †
MB1 BCT misc	`MISC_CONFIG` + `#include` follow ¶	Always	Rename rule †
MB2 BCT misc	`MB2_BCT` + `#include` follow ¶	Always	Rename rule †
Kernel DTB + source DTS	(reference only — see header)	Never forked	Base DTB stays at reference. No pristine binary copy in the overlay tracker; no source DTS fork in `bsp_sources/hardware/` . Carrier deltas live entirely in the DT overlay (next row).
DT overlay skeleton (NEW)	Unconditional	Always	Create `<source.root_path>/hardware/nvidia/<chip>/nv-public/overlay/<chip>-<custom-id>-<custom-sku>+<module-id>-<module-sku>.dts` (skeleton ‡); commit in `hardware/` , push to origin
Per-dir Makefile registration	`<source.root_path>/bsp_sources/hardware/nvidia/<chip>/nv-public/overlay/Makefile`	Always	Append `dtbo-y += <chip>-<custom-id>-<custom-sku>+<module-id>-<module-sku>.dtbo` after the last literal-named `dtbo-y +=` entry (BEFORE the `$(addprefix $(makefile-path)/,$(dtbo-y))` prefix block — inserting after `dtbo-y += $(old-dtbo)` silently drops the .dtbo). Same position-sensitive idiom and snippet as the composite slot's Makefile patch in `../jetson-build-source/references/composite-registration.md#makefile-patch-idempotent-position-sensitive` . Commit in `hardware/` . Without this row, `nvidia-dtbs` never produces the `.dtbo` referenced by the next row's `OVERLAY_DTB_FILE+=` line and `flash.sh` aborts mid-flash on the missing file.
Overlay wire-up	Unconditional	Always	Append `OVERLAY_DTB_FILE+=",<chip>-<custom-id>-<custom-sku>+<module-id>-<module-sku>.dtbo"` to flash-conf fork (extra commit)
nvpmodel config	`rootfs/etc/nvpmodel/nvpmodel_<module-id-num>_<module-sku>.conf`	Always	Filename: append `_<custom-id-file-token>_<custom-sku>`
nvfancontrol config	`rootfs/etc/nvpower/nvfancontrol/nvfancontrol_<module-id-num>_<module-sku>_<carrier-id-num>_<carrier-sku>.conf`	Always	Filename: substitute carrier portion (append `_<custom-id-file-token>_<custom-sku>` if source is module-keyed only)
`nvpower.sh` patch	`rootfs/etc/systemd/nvpower.sh`	Always	Pristine + single customization commit with 4 insertions: (a) cvb cascade `elif [[ "${machine}" =~ "<custom-id>" ]]; then cvb="<custom-id-file-token>"` before reference; (b) inside module-SKU branch set `machine="<module-id>-<module-sku>-<custom-id>-<custom-sku>"` ; (c) nvpmodel cascade branch for composite machine key → `conf_file=` nvpmodel fork; (d) cvb-keyed nvfancontrol cascade branch → `conf_file=` nvfancontrol fork
BPMP DTB	prebuilt at `bootloader/generic/<BPFDTB_FILE>` (alt naming: no `p` prefix, `xxxx` SKU)	Opt-in y/N, default N — module-level, usually shared with reference	Fork binary: pristine + filename sub `-<carrier-id-num>-` → `-<custom-id-file-token>-` (content unchanged). Extra commit on flash-conf fork rewriting `BPFDTB_FILE` to the renamed binary.

¶ #include
follow. Scan each captured

.dts

for

#include "..."

directives anywhere in the file (NVIDIA BSPs put them inside BCT node bodies); carrier-keyed includes join the fork list. Stop at one level.

† Rename rule. Carrier-keyed source (e.g.

…-p3834-xxxx-p4071-0000.dts

) → filename sub

<carrier-id>-<carrier-sku>

→

<custom-id>-<custom-sku>

; rewrite the flash-conf variable (e.g.

PINMUX_CONFIG

) to the renamed filename in the same customization commit. Module portion is preserved verbatim from pristine — if pristine has

p3834-xxxx

, fork keeps

p3834-xxxx

; if pristine has

p3834-0008

, fork keeps

p3834-0008

. Never pin module-SKU on your own. Same rule for any other

xxxx

wildcard in the carrier-SKU position when pristine uses it (e.g.

p4071-xxxx

→

p1234-xxxx

). Module-keyed source (e.g.

…-p3767-dp-a03.dtsi

) → append

_<custom-id-file-token>_<custom-sku>

(underscore-form) or

-<custom-id>-<custom-sku>

(dash-form) plus an extra commit on flash-conf fork rewriting the variable (e.g.

PINMUX_CONFIG

) to the suffixed name. Content never substituted by default; prompt if content holds a literal carrier-id-sku self-reference.

‡ Overlay skeleton. DT plugin overlay (

/plugin/;

) with one

fragment@0

target-path = "/"

; inside

__overlay__

set

model = "<custom_carrier.name> carrier board"

and

compatible = "nvidia,<custom-id>-<custom-sku>+<module-id>-<module-sku>", "nvidia,<chip>"

nvpower.sh

machine narrowing reads

compatible

Edit verification

Re-grep after every

sed

/ patch.

sed

silently no-ops on miss; exit code 0 proves nothing. Multi-line replacements: use Python

str.replace(old, new)

, not multi-line

sed

(brittle to whitespace drift, silent no-ops). Refuse to commit on verification miss.

Summary. Print forks per repo (count + commit SHAs), BPMP-DTB decision, warn-and-skipped rows (mandatory source file missing on this BSP — don't fail the run), overlay path written.

Examples

Trigger phrases the operator might use:

text

derive custom carrier
bootstrap custom carrier
fork carrier board from reference devkit

Minimal

custom_carrier:

block in the active profile that the skill expects to find:

yaml

custom_carrier:
  id: p1234            # any token; need not be NVIDIA pNNNN style
  sku: 0000
  flash_config: p1234.conf
  name: Acme Custom Carrier

Purpose

Customize the per-board fileset for a new carrier board so downstream

customize-*

skills,

nvpower.sh

, and the boot chain land on the custom carrier instead of the reference devkit. Base DTB stays at the reference; carrier deltas live in a DT overlay so a re-derive against a new reference BSP only needs to re-run this skill.

Prerequisites

Active profile resolved per
```
target-platform-contract.md
```
with a
```
custom_carrier:
```
block (id, sku, flash-conf, friendly name).
```
source.root_path/Linux_for_Tegra/.git
```
initialized — run
```
/jetson-init-source
```
first; this skill refuses if the overlay tracker is missing.
```
bsp_image.root_path
```
populated by
```
/jetson-init-image
```
so the reference flash-conf symlink can be resolved.
```
reference_devkit:
```
populated (module + carrier) so the rename rule has carrier-id/sku tokens to substitute away from.

Limitations

Kernel base DTB and its source DTS are not forked — carrier deltas must layer through the DT overlay wired via
```
OVERLAY_DTB_FILE
```
.
BPMP DTB fork is opt-in (default OFF). Most carrier swaps share the reference BPMP DTB; only opt in when board power/clock topology diverges.
Flash-conf content substitution is targeted, not blanket. Vars whose files this skill does not fork (
```
DTB_FILE
```
,
```
TBCDTB_FILE
```
,
```
SCR_CONFIG
```
,
```
PMIC_CONFIG
```
,
```
DEVICEPROD_CONFIG
```
,
```
PROD_CONFIG
```
,
```
MINRATCHET_CONFIG
```
,
```
UPHY_CONFIG
```
, dynamic
```
OVERLAY_DTB_FILE+=
```
) stay at reference values — rewriting them would point at files that do not exist.
Custom-carrier IDs need not follow NVIDIA
```
pNNNN
```
style; the p-stripped numeric token is derived only when the ID matches
```
^p[0-9]{4}$
```
.
Does not customize module-level files. Use the relevant
```
jetson-customize-*
```
skill for pinmux, clocks, fan curves, nvpmodel, PCIe, UPHY, USB, MGBE, or camera deltas.

Troubleshooting

Refuses with "no
custom_carrier:
block" — declare the block in the active profile before re-running; the skill will not infer it.
Refuses with ".git missing in
Linux_for_Tegra/
" — overlay tracker not initialized. Run
```
/jetson-init-source
```
first.
"
<real-conf>
not a symlink" — NVIDIA convention is a
```
<devkit>.conf
```
symlink to
```
<carrier>-<module>-a<rev>.conf
```
; if the top-level is the real conf, the skill warns, treats it as real, and skips the symlink-wrapper row. Not an error.
sed
reported success but the edit is missing —
```
sed
```
silently no-ops on miss. The skill re-greps after every patch and refuses to commit on verification miss; for multi-line replacements switch to Python
```
str.replace
```
.
"chip: unknown" / fallback to
tegra234
— module ID is not in the catalogue; update the catalogue rather than override in the profile.
Commit message preview prompt blocks the run — expected gate per commit-batching; accept, edit, or cancel. On cancel the index is left staged for manual resolution.
A mandatory source file is missing on this BSP — the row is recorded as warn-and-skipped in the summary; the rest of the run still completes.

jetson-derive-carrier

NPX Install

Tags

SKILL.md Content

jetson-derive-carrier

Instructions

Fork plan

Discovery (single batched pass)

Edit verification

Examples

Purpose

Prerequisites

Limitations

Troubleshooting