Unable to boot Kernel on ARM after Memory Remap

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Hi everyone,

I've been working with an imx27ads from Freescale. The BSP from Freescal
includes a Redboot that contains the following memory map:

Phys                 | Virtual              | Enabled|Type
0xA0000000-0xA7FFFFFF| 0x00000000-0x07FFFFFF| Yes    |SDRAM
0xD6000000-0xD6FFFFFF| 0xD6000000-0xD6FFFFFF| No     |SRAM

I've managed to enable the SRAM (verified by loading kernel to it an
reading checksum). I've also disabled the SDRAM and mapped the SRAM to th
base as follows:

Phys                 | Virtual              | Enabled|Type
0xA0000000-0xA7FFFFFF| 0xA0000000-0xA7FFFFFF| No     |SDRAM
0xD6000000-0xD6FFFFFF| 0x00000000-0x00FFFFFF| Yes    |SRAM

I've changed to the best of my knowledge all of the macros where SDRAM wa
being used to use SRAM and the virt_to_phys functions as well. I've als
changed the default entry address to 0xD6008000. I've also verified th
virtual to physical mapping by writing data to the virtual location an
dumping it from the physical to ensure they match.

The problem is this: If I try to boot the kernel with SDRAM disabled an
only SRAM enabled with the second set of memory maps, the "exec" comman
just hangs. It doesn't even get to "Uncompressing Linux". I know th
loading of the kernel into SRAM is successful because I run a 'cksum' an
match it to that on the host.

However, if I simply enable the SDRAM with the second set of memory map
and load the kernel into SRAM(@ 0x100000), then the kernel boot
fine...which suggests to me that there is still a location somewhere tha
is telling the kernel to use 0xA0008000 as its entry point.

I've checked everywhere in the Redboot source but can't figure this out
but then again I've only been working with Redboot for about a week. I
there anyplace in the kernel source where I should make changes as well?
don't _think_ there should be other than possibly changing 'PHYS_OFFSET
(which I tried).  

My goal here is to only use the SRAM and completely disable SDRAM. I
anyone can even shed some remote light on this, I'd greatly appreciate it
please let me know if I can help clarify the issue any better.

Re: Unable to boot Kernel on ARM after Memory Remap
Quoted text here. Click to load it

Is the SRAM flash? Can you stop the boot sequence in the Freescal
debugger, and read the SRAM locations before RedBoot even runs (you migh
have to hand set up the page mapping)?


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