From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hiroshi Doyu <hdoyu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Subject: Re: Tegra DRM device tree bindings
Date: Thu, 28 Jun 2012 09:18:53 +0300
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To: Thierry Reding <thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>
Cc: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" <devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org>, Mark Zhang <markz-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, "dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org" <dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org>, "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" <iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
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On Wed, 27 Jun 2012 16:44:14 +0200
Thierry Reding <thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org> wrote:

> > I think that "coherent_pool" can be used only when the amount of
> > contiguous memory is short in your system. Otherwise even unnecessary.
> > 
> > Could you explain a bit more why you want carveout size on per-board basis?
> 
> In the ideal case I would want to not have a carveout size at all.
> However there may be situations where you need to make sure some driver
> can allocate a given amount of memory. Having to specify this using a
> kernel command-line parameter is cumbersome because it may require
> changes to the bootloader or whatever. So if you know that a particular
> board always needs 128 MiB of carveout, then it makes sense to specify
> it on a per-board basis.

Hm...I could understand somewhat;) but DT can also specify "bootargs"
in dts file, which can support per-board-wide spec too, like the above
sum of carveout needed from all drivers. I just want to avoid
introducing a new parameter additionaly if we can make use of the
existing mechanism.