Nishant Galange writes:
Nishant> Hi all, What does the following code achieve: (Code snippet Nishant> from start.S) boot_cold: Nishant> #if defined(CONFIG_MPC8260ADS) Nishant> lis r3, CFG_DEFAULT_IMMR@h Nishant> nop Nishant> lwz r4, 0(r3) Nishant> nop Nishant> rlwinm r4, r4, 0, 8, 5 Nishant> nop Nishant> oris r4, r4, 0x0200 Nishant> nop Nishant> stw r4, 0(r3) Nishant> nop Nishant> #endif /* CONFIG_MPC8260ADS */
Nishant> Can anyone please tell me the importance/significance of Nishant> this code?
This code fixes incorrect BADDR configuration caused by wrong HRCW supplied by BCSR (FPGA) on some MPC8260ADS boards. It's configured as if there was L2 cache so that lower address lines are not functional (64-bit data bus). Without this code, such a board can't start from 32-bit flash SIMM. This code is for MPC8260ADS only so there should not be any problem.