Hi Tom,
On Friday, April 5, 2013 6:00:30 PM, Tom Rini wrote:
On Fri, Apr 05, 2013 at 03:56:46PM +0200, Beno??t Th??baudeau wrote:
Hi Albert,
On Friday, April 5, 2013 8:00:43 AM, Albert ARIBAUD wrote:
Hi Beno??t,
[snip]
IIUC, this future patch would increase the limit for SPL run-time size, as the constant against which the ASS tests __bss_end for would necessarily be greater than it is now. Correct? If so, this future patch should not break any target, as it would loosen the constraint, not tighten it.
Yes, it would either be the same or relaxed a bit, depending on the chosen option:
- Define CONFIG_SPL_BSS_MAX_SIZE and test against CONFIG_SPL_MAX_SIZE + CONFIG_SPL_BSS_MAX_SIZE, the sum remaining the same as or being larger than currently, depending on the new values for CONFIG_SPL_MAX_SIZE and CONFIG_SPL_BSS_MAX_SIZE.
- Define a new config meaning text + data + rodata + bss (e.g. CONFIG_SPL_MAX_RAM_SIZE or CONFIG_SPL_MAX_MEM_FOOTPRINT), and just replace CONFIG_SPL_MAX_SIZE with it for the users of arch/arm/cpu/u-boot*.lds, taking care that this was the only meaning those users were giving to CONFIG_SPL_MAX_SIZE.
The first option would probably be preferable, using the same value for CONFIG_SPL_MAX_SIZE, and a non-zero value for CONFIG_SPL_BSS_MAX_SIZE.
I think the problem is that Tegra really needs the second case as their constraint is "must fit below next part of payload". We can assume the users of that linker script today care about footprint and update their define I believe. da850evm and the rest of the davinci platforms would also be a case to convert to this, but the omap*/am3* platforms would not.
Yes, then let's have an assert in arch/arm/cpu/u-boot*.lds with a different config name (as in option 2 above) just for Tegra, and another assert for CONFIG_SPL_MAX_SIZE against __bss_start.
And all users of CONFIG_SPL_MAX_SIZE should be checked to make sure that there is not another special case somewhere.
Best regards, Benoît