what is srmmu_inherit_prom_mappings for?

[Chan Kim <ckim@xxxxxxxxxx>]

Hi,
I was following the srmmu_paging_init code. (linux 3.3) while tyring to solve the problem of not being able to handle the page fault when accessing the frame buffer on user program(busybox). I know there comes another version of page table setup after this stage.
Anyway.. after bootmem_init and srmmu_nocache_calcsize and srmmu_nocache_init calls,
I see
srmmu_inherit_prom_mappings(0xfe400000,(LINUX_OPPROM_ENDVM-PAGE_SIZE));
I don't know what this is doing..
Could someone kindly explain it to me?
Thanks,
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