3fd673cf36
The current situation has the 64MB user flash at an awkward alignment; shifted back from 0xfc00_0000 by 8M, to leave an 8MB hole for the soldered on boot flash @ EOM. But to switch to optionally supporting booting off the 64MB flash, the 64MB will then be mapped at the sane address of 0xfc00_0000. This leads to awkward things when programming the 64MB flash prior to transitioning to it -- i.e. even though the chip spans from 0xfb80_0000 to 0xff7f_ffff, you would have to program a u-boot image into the two sectors from 0xfbf0_0000 --> 0xfbff_ffff so that it was in the right place when JP12/SW2.8 were switched to make the 64MB on /CS0. (i.e. the chip is only looking at the bits in mask 0x3ff_ffff) We also have to have three TLB entries responsible for dealing with mapping the 64MB flash due to this 8MB of misalignment. In the end, there is address space from 0xec00_0000 to 0xefff_ffff where we can map it, and then the transition from booting from one config to the other will be a simple 0xec --> 0xfc mapping. Plus we can toss out a TLB entry. Note that TLB0 is kept at 64MB and not shrunk down to the 8MB boot flash; this means we won't have to change it when the alternate config uses the full 64MB for booting, in TLB0. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org> |
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| Makefile | ||
| ddr.c | ||
| law.c | ||
| sbc8548.c | ||
| tlb.c | ||