[Arm-netbook] RAM, uboot

[David Given]

On 10/05/12 17:10, Tomasz Jóźwiak wrote:
[...]
> I found some interesting setting in kernel configuration
> System Type -> All winner system configure -> Memory reserved size in KB
> 
> I changed value from 70MB to 20MB and set fbmem=1 and i have got 391MB 
> total memory under debian 6 (before was ~350MB)

Having investigated the source code, the reserved memory blocks are:

VE: sized by a compile-time constant (the one described above)
FB: sized by the fbmem boot option
GPS: enabled by the gps_used .bin key
G2D: enabled by the g2d_used .bin key

The VE base address is 0x43000000, and the .bin data is loaded at the
base of it. (The DRAM is mapped at 0x40000000.) I don't know what it's
used for --- the FEX file doesn't explicitly refer to any memory-mapped
hardware in that range, but there are all the weird port:PA00 references...

With GPS turned off, FB set to one byte, and VE set to 128kB, I get
443900kB of memory as reported by /proc/meminfo, which is reasonably
decent. I'll report back if anything obviously doesn't work.

But I still want to know why dmesg reports this:

[    0.000000] Total Detected Memory: 512MB with 1 banks
...
[    0.000000] Memory: 448MB = 448MB total

448? Where's the other 64MB going?

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