Re: [PATCH v2 08/20] ARM: LPAE: MMU setup for the 3-level pagetable format

From: Russell King - ARM Linux
Date: Tue Nov 23 2010 - 12:33:40 EST


On Tue, Nov 23, 2010 at 11:38:15AM +0000, Catalin Marinas wrote:
> On 22 November 2010 13:10, Russell King - ARM Linux
> <linux@xxxxxxxxxxxxxxxx> wrote:
> > Are you sure these shifts by 18 places are correct?  They're actually
> > (val >> SECTION_SHIFT) << 2, so maybe they should be (SECTION_SHIFT -
> > PMD_WORDS) ?
>
> SECTION_SHIFT - PMD_ORDER is (20 - 2) for classic page tables and (21
> - 3) for LPAE. But we could change the 18 to some macros for
> clarification (the line would be long though).

So yes, it's SECTION_SHIFT - PMD_ORDER, which is how they should be
used IMHO. I don't see why another macro would be necessary.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/