[U-Boot] [PATCH v2 2/6] sunxi: add Kconfig option for the maximum accessible DRAM

Maxime Ripard
2018-03-23T09:39:25Z

On Fri, Mar 23, 2018 at 04:18:53PM +0800, Icenowy Zheng wrote:
> Allwinner 64-bit SoCs can use 4GiB DRAM chip, however their memory map
> has only allocated 3GiB for DRAM, so only 3GiB of the DRAM is
> accessible.

How would that work in Linux?

> Add a Kconfig option for the maximum accessible DRAM.
>
> For A80 it should be a much higher value (8GiB), but as I have no A80
> device to test and originally U-Boot only supports 2GiB DRAM on A80, it
> currently still falls under the 2GiB situation.

I guess we have LPAE on armv7 to deal with this nicely.

Maxime

--
Maxime Ripard, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering