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From: cinap_lenrek@felloff.net
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X-Bullshit: mobile polling-based configuration-based HTTP over SSL framework rails-oriented generator 
Subject: Re: [9front] Porting RTL8111 (ether8169) driver to bcm64
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> Are there already similar calls in 9front and I’ve (stupidly) overlooked them? 

no. i/o space is not supported on arm. this has nothing todo
with 9front.

i'm pretty sure the rtl chip will provide a membar with memory
mapped registers in addition to the i/o port interface,
you do not need special calls for this.

just vmap() the and access the registers with loads and stores.

get the datasheet and programmers manual for the rtl chip.

> Should it be as simple as adding the platform dependent calls in the driver
> to get it to work on the Pi, or is there more work that needs to be done to
> the bcm64 PCIe interface?

for dma, you need to manually keep the caches coherent with
the device using dmaflush() calls (see in port/usbxhci.c as an example).

this is the biggest reason most drivers cannot direcly be used
on arm, tho shouldnt be too difficult to make it work.

--
cinap