Re: [Etherboot-developers] Q: USE_LOWMEM_BUFFER?

[<ke...@us...>]

>I'm a little curious about the history of USE_LOWMEM_BUFFER, and
>the reasons for it.  The primary reason is that when I start
>compiling I can easily get a huge .bss section, because all of the
>drivers have a seperate transmit buffer.
>
>I'm not advocating reviving USE_LOWMEM_BUFFER but instead looking
>at what it would take to use the old USE_LOWMEM_BUFFER infrastructure
>to have a common transmit buffer.

USE_LOWMEM_BUFFER is a hack that Klaus Espenlaub created for some 4.x
drivers because at that time Etherboot only had 32kB-- from 0x98000
upwards. In 5.x by refining mknbi and juggling the segments around I
gave Etherboot 48kB-- from 0x94000 upwards, obviating the need for
USE_LOWMEM_BUFFER which I thought was ugly.

It would probably be better to rework the means by which drivers get
buffers, possibly by providing a library which returns pointers to a
common buffer area. Then the decision where to put the buffer area is
concentrated in the library, not scattered throughout drivers.