On 03 Apr 2017, at 12:05, Andre Przywara andre.przywara@arm.com wrote:
On 03/04/17 10:40, Lukasz Majewski wrote:
Hi Andre ,
So far we were not using the FIT image format to its full potential: The SPL FIT loader was just loading the first image from the /images node plus one of the listed DTBs. Now with the refactored loader code it's easy to load an arbitrary number of images in addition to the two mentioned above. As described in the FIT image source file format description, iterate over all images listed at the "loadables" property in the configuration node and load every image at its desired location. This allows to load any kind of images:
- firmware images to execute before U-Boot proper (for instance
ARM Trusted Firmware (ATF))
- firmware images for management processors (SCP, arisc, ...)
- firmware images for devices like WiFi controllers
- bit files for FPGAs
- additional configuration data
- kernels and/or ramdisks
Would it be possible to adopt this code to also load SDRAM controller configuration data?
As it stands at the moment, this code is run when the SPL is finished with initialising the platform and is about to load and hand over to U-Boot proper. It would need to be investigated if the device driver required to actually load the FIT image works without DRAM being available (as in: do we have enough heap and stack, for instance). Also I am not sure the FIT (fdt) parsing code is really tuned for low memory, since normally it runs with DRAM already available.
So while this doesn't sound impossible, it's probably some work ahead, depending on the resource limitation you have in SPL on your platform.
The more general solution would be to move towards having a TPL in addition to the SPL…
Regards, Philipp.