LPC does DMA just fine, there are off the shelf LPC SuperIO chips with FDD support. There is also this project trying to bring ISA back from LPC https://www.vogons.org/viewtopic.php?t=93291

>ISA became the LPC bus, which still exists - and I believe will keep existing, because TPMs

already superseded by almost 10 year old eSPI. eSPI dropped DMA support.