Re: [PATCH] ath5k: Use mips generic dma-mapping functions to avoid seqfault on AHB chips

[Jiri Slaby <jirislaby@gmail.com>]

On 02/15/2011 11:16 PM, Jiri Slaby wrote:
> On 02/15/2011 10:39 PM, Nikolay Ledovskikh wrote:
>>> Maybe the address you got from the platform side was already ored by
>>> KSEG1...
>>
>> I took a look at openwrt atheros platform code and suppose you are right.
>> So what we should do for now? Add pointer cast (void __iomem *)?
>> Because ioremap_nocache doesn't work as expected. I think it's better
>> to rewrote the openwrt
>> code, but not now.
> 
> So I've found:
> http://www.google.com/codesearch/p?hl=en#sayuPQDVf4c/trunk/openwrt/target/linux/atheros/patches-2.6.32/100-board.patch&q=ar231x-wmac&sa=N&cd=4&ct=rc
> 
> There, the res->start may be either of the following:
> AR531X_WLAN0 .. 0x18000000
> AR531X_WLAN1 .. 0x18500000


> AR2315_WLAN0 .. 0xB0000000

Or maybe this should be 0x10000000 in openwrt in the first place? Then
ioremap should do the right thing, right?

> I suppose you have the 3rd otherwise it should die without ORing KSEG1?
> 
> Or maybe MIPS guys will correct me? (The problem is that ioremap of one
> of the addresses above kills the box. If Nikolaj removes the ioremap and
> uses the address directly, it works for him. I'm saying it will die for
> the first 2 addresses if we remove ioremap completely -- from what I
> found in MIPS specs.)
> 
> I _think_ there should be (instead of ioremap):
> sc->iobase = (void __iomem *)KSEG1ADDR(res->start);
> 
> Then we do readl(sc->iobase) et al. in ath5k.
> 
> thanks,
-- 
js