Re: [U-Boot] [PATCH] keystone2: add high memory test

On Wed, Jul 08, 2015 at 11:51:39AM -0400, Vitaly Andrianov wrote:

Keystone2 SOC physical DDR3 address range is outside the first 4GB and cannot be entirely accessible without MMU enabled. Only first 2GB of the physical memory have 32-bits aliased addresses. This patch adds u-boot shell command that allows to enable/disable MMU and map the 1GB of 36bits physical memory to the first 4GB address range.

Signed-off-by: Vitaly Andrianov vitalya@ti.com

arch/arm/mach-keystone/Makefile | 3 +- arch/arm/mach-keystone/highmem.c | 162 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 164 insertions(+), 1 deletion(-) create mode 100644 arch/arm/mach-keystone/highmem.c

The code looks reasonable. But why do we need this? Thanks.