[PATCH] ARM: allow, but warn, when issuing ioremap() on RAM
Felipe Contreras
felipe.contreras at gmail.com
Thu Oct 14 10:47:09 EDT 2010
On Mon, Oct 11, 2010 at 6:25 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Sun, Oct 10, 2010 at 04:52:36AM +0300, Felipe Contreras wrote:
>> At the time 'fixup' is called, 'meminfo' is empty; the tags haven't
>> been parsed. So my solution is to move the memblock_add() after
>> 'reserve', and pass 'meminfo' as an argument:
>
> Here's a different approach which will work. This pushes ARM further
> towards using memblock for everything relating to memory init (although
> we still have the old membank stuff around.)
>
> The advantage with this is that memblock is now used as the basis for
> determining where memory is, setting up the maps, freeing memory into
> the pools, etc.
>
> What this also means is that this code in the ->reserve callback:
>
> size = min(size, SZ_2M);
> base = memblock_alloc(size, min(align, SZ_2M));
> memblock_free(base, size);
> memblock_remove(base, size);
Why align to SZ_2M both the start and end?
> will result in [base+size] being removed from the available memory,
> using highmem if available, if not from lowmem and removing it from
> the lowmem memory map - which is exactly the behaviour we want.
Makes sense to me.
> arch/arm/mm/init.c | 160 +++++++++++++++++++++++++++++++++++-----------------
> arch/arm/mm/mmu.c | 43 ++++++++------
> mm/memblock.c | 4 +
> 3 files changed, 138 insertions(+), 69 deletions(-)
This works fine:
Tested-by: Felipe Contreras <felipe.contreras at gmail.com>
--
Felipe Contreras
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