Messages in this thread Patch in this message |  | | From | Keith Owens <> | Subject | Re: 2.1.21-patch_drivers_net-1 | Date | Thu, 16 Jan 1997 10:40:42 +1100 |
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On Wed, 15 Jan 1997 20:42:48 +0000 (GMT), alan@lxorguk.ukuu.org.uk (Alan Cox) wrote: >> +++ linux/drivers/net/lance.c Wed Jan 15 15:10:18 1997 >> @@ -309,7 +309,7 @@ >> { >> int *port; >> >> - if (high_memory <= 16*1024*1024) >> + if (high_memory <= (void *) MAX_DMA_ADDRESS) >> lance_need_isa_bounce_buffers = 0; > >Rejected. The original code is correct. The lance 16bit has a 24bit internal >DMA counter limit.
Since the kernel moved, high_memory is always (at least) 0xC0000000 so the original code always fails and uses bounce buffers. On my 20Mb system, high_memory = 0xC1400000, MAX_DMA_ADDRESS = 0xC10000000. The alternative was
virt_to_bus(high_memory) <= 16*1024*1024
but I dislike hard coded magic numbers.
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