imx53 memory detection

[Sascha Hauer]

On Wed, Apr 13, 2016 at 09:38:35PM -0700, Jason Cobham wrote:
> Hi Sascha,
> 
> Thanks for the quick reply.
> 
> > So you replaced barebox_arm_entry with imx53_barebox_entry, right? What
> > memory size do you have and what size gets detected then?
> 
> Yes, I used imx53_barebox_entry. I have two boards, 512MB/1G. In
> further testing, I found the 512MB board was detected correctly, and
> the 1G board was detected at 2G.
> 
> ...
> 
> > As a first step you should remove the /memory node in
> > arch/arm/dts/imx53-ccxmx53.dtsi. Since there are different possible
> > memory setups for this board it is wrong anyway. Then it would be
> > interesting what imx_esdctl_v4_add_mem() detects. I believe it should be
> > possible to fix it if it detects the wrong memory size.
> 
> For the 1G board, I removed the memory node and looked into
> imx_esdctl_v4_add_mem(). I found:
> add_mem: cs0 base: 0x70000000 cs0 size: 0x40000000
> add_mem: cs1 base: 0xb0000000 cs1 size: 0x40000000
> 
> Going further into it, I found in the imx_v4_sdram_size() read the
> following from the esdctl registers:
> ctlval:0xc4110000, esdmisc:0xc00016d0 which is set from the
> appropriate flash-header file.
> 
> The ram populated on the 1G board is MT47H128M16 – 128 Meg x 16 (16
> Meg x 16 x 8 banks).
> Comparing the register setting against the datasheet for the ram chips
> looks like there was a mistake in the row setting of the 1G
> flash-header. After updating it to what I believe is correct setting:
> (ctlval:0xc3110000, esdmisc:0xc00016d0), the memory is now detected
> correctly.

So you say that the flash header sets up memory of twice the actual size
which then misleads the detection code? Then this is worth fixing, also
the /memory node should be removed. Care to send patches for this?

Thanks
 Sascha

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