[PATCH rtems 0/3] bsps/atsam: Various small improvements

[Christian Mauderer]

Hello,

this patch set adds a number of improvements to the ATSAM BSP. The
patches accumulated over the last few month on a branch.

The first one fixes a problem with unidirectional SPI transfers. The
current driver would overwrite or send data at / from 0x00.

The second one adds a small protection for the NULL pointer.

The last one adds the ability to use a custom SDRAM configuration and
size. That was possible on RTEMS 5 by overwriting some of the configure
variables during build and the RAM configuration structure in the
application. With the new build system, the variables now depend purely
on the RAM chip and can't be overwritten any more. This adds a
possibility for a custom RAM size again.

Best regards

Christian