'\" t
.\"     Title: nvme-fw-download
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 09/18/2026
.\"    Manual: NVMe Manual
.\"    Source: NVMe
.\"  Language: English
.\"
.TH "NVME\-FW\-DOWNLOAD" "1" "09/18/2026" "NVMe" "NVMe Manual"
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.SH "NAME"
nvme-fw-download \- Download all or a portion of an nvme firmware image\&.
.SH "SYNOPSIS"
.sp
.nf
\fInvme\fR [<global\-options>] \fIfw download\fR <device>
                        [\-\-fw=<firmware\-file> | \-f <firmware\-file>]
                        [\-\-xfer=<transfer\-size> | \-x <transfer\-size>]
                        [\-\-offset=<offset> | \-O <offset>]
                        [\-\-stream]
.fi
.SH "DESCRIPTION"
.sp
The Firmware Image Download command is used to download all or a portion of the firmware image for a future update to the controller\&. The Firmware Image Download command may be submitted while other commands on the Admin Submission Queue or I/O Submission Queues are outstanding\&. The Firmware Image Download command copies the new firmware image (in whole or in part) to the controller\&.
.sp
The firmware image may be constructed of multiple pieces that are individually downloaded with separate Firmware Image Download commands\&. Each Firmware Image Download command includes a Dword Offset and Number of Dwords that specify a Dword range\&. The host software shall ensure that firmware pieces do not have Dword ranges that overlap\&. Firmware portions may be submitted out of order to the controller\&.
.sp
The new firmware image is not applied as part of the Firmware Image Download command\&. It is applied following a reset, where the image to apply and the firmware slot it should be committed to is specified with the Firmware Commit command (nvme fw\-commit <args>)\&.
.sp
Note: nvme\-cli must allocate a contiguous (linear) memory buffer and map the firmware binary into it\&. To do this, nvme\-cli first attempts to allocate the buffer using huge TLB pages\&. If allocation using huge pages fails, it falls back to using posix_memalign() combined with madvise()\&. If the kernel rejects the huge page advice, nvme\-cli keeps the aligned buffer and lets the I/O path attempt to map it\&.
.sp
The optional \-\-stream mode avoids allocating a buffer for the complete firmware image\&. It reads and downloads one transfer\-sized portion at a time\&.
.sp
To increase the likelihood of success, you may want to pre\-allocate a number of huge pages before initiating the firmware download:
.sp
.if n \{\
.RS 4
.\}
.nf
echo 20 > /proc/sys/vm/nr_hugepages
.fi
.if n \{\
.RE
.\}
.sp
For more details, refer to: \m[blue]\fBhttps://www\&.kernel\&.org/doc/Documentation/vm/hugetlbpage\&.txt\fR\m[]
.sp
The bare \fInvme fw\-download\fR form (without a space) still works as a deprecated alias and will be removed in a future major version\&. New scripts should use \fInvme fw download\fR instead\&.
.SH "OPTIONS"
.PP
\-f <firmware\-file>, \-\-fw=<firmware\-file>
.RS 4
Required argument\&. This specifies the path to the device\(cqs firmware file on your system that will be read by the program and sent to the device\&.
.RE
.PP
\-x <transfer\-size>, \-\-xfer=<transfer\-size>
.RS 4
This specifies the size to split each transfer\&. This is useful if the device has a max transfer size requirement for firmware\&. It defaults to 4k\&.
.RE
.PP
\-O <offset>, \-\-offset=<offset>
.RS 4
This specifies the starting offset in dwords\&. This is really only useful if your firmware is split in multiple files; otherwise the offset starts at zero and automatically adjusts based on the
\fIxfer\fR
size given\&.
.RE
.PP
\-\-stream
.RS 4
Read and download one transfer\-sized portion of the firmware image at a time instead of mapping the complete image into memory\&. This avoids the huge page requirement and limits memory use to the transfer size\&.
.RE
.SH "GLOBAL OPTIONS"
.sp
The following options are defined at the top\-level nvme command and are available to this subcommand:
.PP
\-\-dry\-run
.RS 4
Print the command that would be executed, but do not actually execute it\&.
.RE
.PP
\-\-no\-ioctl\-probing
.RS 4
Disable probing for 64\-bit IOCTL support\&.
.RE
.PP
\-\-no\-retries
.RS 4
Disable retry logic on transient errors\&.
.RE
.PP
\-o <fmt>, \-\-output\-format=<fmt>
.RS 4
Set the reporting format to
\fInormal\fR,
\fItabular, \*(Aqjson\fR, or
\fIbinary\fR\&. Only one output format may be used at a time\&.
.RE
.PP
\-\-output\-format\-version=<version>
.RS 4
Select the output format version\&. Version
\fI1\fR
uses the original field naming, while version
\fI2\fR
(default) provides more consistent and script\-friendly field names\&.
.RE
.PP
\-\-timeout=<ms>
.RS 4
Set the timeout for the command in milliseconds\&.
.RE
.PP
\-v, \-\-verbose
.RS 4
Increase the level of detail in the output\&. May be specified multiple times to further increase verbosity\&.
.RE
.sp
These options can also be set as machine\-wide defaults in nvme\-cli\&.conf(5)\&. A command\-line flag always overrides the file\&.
.SH "EXAMPLES"
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Transfer a firmware size 128KiB at a time:
.sp
.if n \{\
.RS 4
.\}
.nf
# nvme fw download /dev/nvme0 \-\-fw=/path/to/nvme\&.fw \-\-xfer=0x20000
.fi
.if n \{\
.RE
.\}
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Read and download a firmware image one transfer\-sized portion at a time:
.sp
.if n \{\
.RS 4
.\}
.nf
# nvme fw download /dev/nvme0 \-\-fw=/path/to/nvme\&.fw \-\-stream
.fi
.if n \{\
.RE
.\}
.RE
.SH "NVME"
.sp
Part of the nvme\-user suite