RE: [PATCH v4] ARM: Thumb-2: Symbol manipulation macros for function body copying

[Santosh Shilimkar <santosh.shilimkar@ti.com>]

> -----Original Message-----
> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
> owner@vger.kernel.org] On Behalf Of Dave Martin
> Sent: Monday, January 17, 2011 9:06 PM
> To: Jean Pihet
> Cc: linux-arm-kernel@lists.infradead.org; linux-
> omap@vger.kernel.org; Jean Pihet
> Subject: Re: [PATCH v4] ARM: Thumb-2: Symbol manipulation macros for
> function body copying
>
> Hi,
>
> On Mon, Jan 17, 2011 at 2:02 PM, Jean Pihet
> <jean.pihet@newoldbits.com> wrote:
>
> [...]
>
> > Note that aligning the source and destination pointers to a
> multiple
> > of 8 bytes has an impact on the behavio(u)r and so must be
> carefully
> > thought and tested on OMAP1/2/3 platforms.
>
> Do you have any specific concerns regarding this?
>
> Currently, the only issue I can think of is that the need to
> allocate
> aligned memory from the SRAM will increase the total amount
> allocated,
> which could be a problem if we end up overflowing the available
> SRAM.
>
> This does not appear to happen in the case I've tested -- I
> currently
> round up the amount allocated in omap_sram_push to be a multiple of
> 8
> bytes.  This, combined with a couple of ".align 3" directives, is
> enough to get me a booting system on omap3... but I haven't tested
> exhaustively.
>
I don't think there can be overflow issue considering it's current
use and available SRAM on OMAP.

How much additional memory you will need to take care of
alignment.

Max additional memory = total fns * ( 8 + 8)
			    = ~ 10 * 16
			    = 160 bytes.

Should be ok.

Regards,
Santosh