Re: [PATCH net-next] pcnet32: remove VLB support
From: David Laight <hidden>
Date: 2026-01-15 22:29:57
On Tue, 6 Jan 2026 23:18:31 -0800 Ethan Nelson-Moore [off-list ref] wrote:
This allows the code managing device instances to be simplified significantly. The VLB bus is very obsolete and last appeared on P5 Pentium-era hardware. Support for it has been removed from other drivers, and it is highly unlikely anyone is using it with modern Linux kernels.
That device bring back memories, but only the PCnet/ISA and PCnet/PCI variants. IIRC both are basically AMD 'lance' ethernet chips with a built-in bus interface (the ISA one is ISA pnp). So have a limit of 24 address bits (I don't remember using a different ring format than any other lance variant - just for the Sun HME). I don't remember anything about VLB - just ISA, EISA and PCI. There are two variants of the PCnet/PCI - the '790 and '791. Each had its own quirks, I later thought that the 791 might have been intended to support 100M - but didn't work. The ISA variant needed one of the ISA DMA channels put into 'cascade mode' (the kernel didn't really want to allow that), but was about the only ISA card capable of saturating 10M ethernet with smallish packets (IIRC in a 33MHz 486, but not the similar 386 box). (And 'fun' to set to fixed IO addresses on a motherboard that supported ISA pnp for a kernel that didn't.) One bit you might disable is the probe_vlbus() code. You really never want that sort of probe code, it can have a disastrous effect on other hardware at the address being probed. I didn't 'steal' the green datasheet book :-( David