[U-Boot] [PATCH] malloc_simple: Add simple malloc free function

[Chin Liang See <clsee@altera.com>]

Hi Marek,

On Wed, 2016-08-03 at 08:58 +0200, Marek Vasut wrote:
> On 08/03/2016 05:24 AM, Chin Liang See wrote:
> > Enable a simple malloc implementation which will minimize
> > memory usage prior relocation. This is essential as memory
> > available prior location is internal memory and limited in
> > size.
> > 
> > This implementation will stored last 2 usage of malloc. When
> > free is invoked and the free address matched, we shall revert
> > to previous value of gd->malloc_ptr that we stored.
> 
> This looks unnecessarily convoluted and fragile design.
> What problem do you observe and on what platform ?

Actually this for our Arria10 SoC device. In order to get DDR working,
we need to program FPGA. To improve the usability, we put the FPGA
programming file (RBF) into FAT partition.

In that sense, we would need to use FAT driver prior relocation / DDR
available. Due to that, the malloc usage is high and memory available
is limited prior DDR available. 

The simple malloc helps but without the free, its consumed way too much
memory than saving. Hence this simple malloc free patch help. So I
believe this would benefits those who are executing complex operation
prior relocation :) 

Thanks
Chin Liang