[PATCH] PPC 85xx failure with odd memory sizes and CONFIG_HIGHMEM

[Rune Torgersen]

> From: Dale Farnsworth
> 
> The CONFIG_FSL_BOOKE mmu setup code fails when CONFIG_HIGHMEM=y
> and the 3 fixed TLB entries cannot exactly map the lowmem size.
> Each TLB entry can map 4MB, 16MB, 64MB or 256MB, so the failure
> is observed when the kernel lowmem size is not equal to the
> sum of up to 3 of those values.

Does this mean you cannot run 1G of lowmem on a 85xx?

On 82xx I run 1G of lowmem, and when we finaly upgrade our product to a
85xx something, Iw was planning on doing the same.

(For those interested:
To run 1G lowmwm on 82xx (at least under arch/ppc)
CONFIG_ADVANCED_OPTIONS=y
CONFIG_HIGHMEM_START=0xfe000000
CONFIG_LOWMEM_SIZE_BOOL=y
CONFIG_LOWMEM_SIZE=0x40000000
CONFIG_KERNEL_START_BOOL=y
CONFIG_KERNEL_START=0xa0000000