CXGB(4)

💖 CXGB(4) — the Chelsio T3 10 Gigabit Ethernet adapter driver, but make it a group chat 💖

okay bestie, sit DOWN, because cxgb(4) is the driver for your Chelsio T3 10 Gigabit Ethernet adapter and she is thriving. this is the kernel interfaces manual page, and i'm gonna walk you through every single thing in it, no gatekeeping, no cap 🫶

---

✨ NAME ✨

cxgb — the Chelsio T3 10 Gigabit Ethernet adapter driver. that's her. that's the girl. 💅

---

🌸 SYNOPSIS 🌸

so like, if you wanna bake this driver into your kernel (main character energy, no modules needed), you drop these lines into your kernel configuration file:

device firmware
device cxgb

but if you'd rather load her as a module at boot time (lowkey easier, honestly), you put this one line in loader.conf(5):

if_cxgb_load="YES"

and that's it. slay. ✨

---

🦋 DESCRIPTION 🦋

okay so here's what cxgb can do, and the list is long because she's an overachiever:

• Transmit/Receive checksum offload
• Jumbo Frames
• TCP segmentation offload (TSO)
• Large Receive Offload (LRO)
• VLAN hardware insertion / extraction
• VLAN checksum offload

obsessed. truly. if you want more hardware tea, the site is http://www.chelsio.com/ 💖

got questions about hardware requirements? go read the documentation that came with your Chelsio T3 adapter, bestie, because every single hardware requirement listed in there applies to using it with FreeBSD. periodt.

Jumbo Frames? that's handled through the interface MTU setting. pick an MTU bigger than 1500 bytes with the ifconfig(8) utility and the adapter gets configured to receive and transmit Jumbo Frames. the maximum MTU size for Jumbo Frames is 9000. don't get cute with it. 🎀

and for more info on configuring this device, go see ifconfig(8). iykyk.

---

👑 HARDWARE 👑

the cxgb driver supports 10 Gigabit and 1 Gigabit Ethernet adapters based on the T3 and T3B chipset:

• Chelsio 10GBase-CX4
• Chelsio 10GBase-LR
• Chelsio 10GBase-SR

three icons. no notes. 🌈

---

🧚 LOADER TUNABLES 🧚

tunables can be set at the loader(8) prompt before booting the kernel, or stored in loader.conf(5). your call, babe, both are valid. ⭐

---

💀 DIAGNOSTICS 💀

these are the messages you do NOT wanna see, bestie, i'm so serious:

• cxgb%d: Unable to allocate bus resource: memory — a fatal initialization error has occurred. 😭
• cxgb%d: Unable to allocate bus resource: interrupt — also a fatal initialization error. 😭
• cxgb%d: Could not find firmware image %s — the appropriate firmware kld module was not installed. this one is a fatal initialization error too.

fr fr, all three of these are fatal initialization errors. not a vibe. fix them before you come crying to me. 🥲

---

💜 SUPPORT 💜

for general info and support, go to the Chelsio support website at: http://www.chelsio.com/

and if you find an actual issue with the released source code, on a supported kernel, with a supported adapter — email the specific information related to the issue to ⟨support@chelsio.com⟩. be specific. give them the deets. they wanna help you. 🫶

---

🔥 SEE ALSO 🔥

altq(4), arp(4), netintro(4), ng_ether(4), ifconfig(8)

(the whole friend group, honestly) ✨

---

🎀 HISTORY 🎀

the cxgb device driver first appeared in FreeBSD 6.3 and FreeBSD 7.0. a legend from the jump. 👑

---

🌟 AUTHORS 🌟

the cxgb driver was written by Kip Macy <kmacy@FreeBSD.org> with substantial support from Scott Long <scottl@FreeBSD.org>. give them their flowers, they earned them. 💐

---

and that's the whole page, bestie!! this one came from the Debian crew and is dated March 14, 2007 — yeah, she's been iconic for a minute and she's still serving. go configure your adapter. mwah 💋🌸💖