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CSB336 i.MX1/i.MXS memory map organization
- SDRAM starts at address 0x08000000 but 2 MB are reserved
for boot-block/loader (or other use) before RTEMS image
origin/load address (that is kept from previous setup)
- Caching of 30 MB of SDRAM used for RTEMS (start at 0x08200000)
is changed to writeback mode which provides higher throughput.
- The first 1 MB of RTEMS dedicated SDRAM is remapped to address 0
to provide area for ARM CPU exceptions table.
- Internal registers and rest of the Flash (above 1 MB) are mapped
one to one. Registers region is extended to 2 MB to cover
eSRAM found on i.MX1 chip variant.
- The first two megabytes of SDRAM unused by RTEMS are mapped
with attributes to allow specific purposes.
- the first MB (at address 0x08000000) is nocached to allow
directly set some values read by booot-block after warm reset
- the second MB (at address 0x08100000) is set for write-through
caching. That allows to use memory for LCD frame-buffer without
need to flush cache after each redraw.
Signed-off-by: Pavel Pisa <pi@baree.pikron.com>