Hi Simon,
On 7/11/19 13:42, Simon Glass wrote:
Hi Walter,
On Thu, 7 Nov 2019 at 06:30, Walter Lozano walter.lozano@collabora.com wrote:
Hi Ezequiel,
On 5/11/19 20:30, Ezequiel Garcia wrote:
On Tue, 5 Nov 2019 at 15:12, Walter Lozano walter.lozano@collabora.com wrote:
Hi Ezequiel,
On 5/11/19 13:56, Ezequiel Garcia wrote:
Hello Walter,
Thanks for the patch.
On Tue, 5 Nov 2019 at 12:27, Walter Lozano walter.lozano@collabora.com wrote:
The support of libfdt should only be needed when OF_CONTROL is enabled and OF_PLATDATA is not, as in other cases there is no DT file to query.
This patch fixes this dependency allowing to save some space.
Can you add some more information about the space saving?
Sure, I will add some additional information about the static footprint. However according to my understanding the impact depends on how well different drivers supports features like OF_PLATDATA. For instance, in my current configuration it saves 2 KB.
Not sure I follow you. This patch adds a condition which adds/removes code based on some conditions. So, it should depend on the arch, but otherwise the reduction is an invariant as it just depend on the size of the code that is being added/removed. Or am I missing something?
The idea behind this patch is to break the dependency of libfdt when it is not needed. A specific example of this is found when building SPL using OF_PLATDATA, which basically removes DT so there is no sense of having libfdt present in SPL. Unfortunately as OF_PLATDATA has little support, drivers tend to assume that there is a DT and try to query different properties, which of course return no data. In this context, the idea is to keep the same behavior but reducing the SPL size, while trying to improve drivers.
I actually sent a similar patch in September but never fixed the problems it caused. I just resent it as a series:
http://patchwork.ozlabs.org/project/uboot/list/?series=141416
Thanks for pointing to this patchset, it looks like the approach I was looking for to overcome the the issue with libfdt and other dependencies in a proper way. I'll try to use your same approach in other drivers.
[..]
Regards, Simon
Regards,
Walter