From: Suzuki Poulose Date: Tue, 21 Aug 2012 01:42:43 +0000 (+0000) Subject: powerpc: Export memory limit via device tree X-Git-Tag: omap-for-v3.7-rc1/fixes-cpufreq-signed~10^2~75 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4bc77a5ed215b4ec9cc39d5f55323b2e68000055;p=pandora-kernel.git powerpc: Export memory limit via device tree The powerpc kernel doesn't export the memory limit enforced by 'mem=' kernel parameter. This is required for building the ELF header in kexec-tools to limit the vmcore to capture only the used memory. On powerpc the kexec-tools depends on the device-tree for memory related information, unlike /proc/iomem on the x86. Without this information, the kexec-tools assumes the entire System RAM and vmcore creates an unnecessarily larger dump. This patch exports the memory limit, if present, via chosen/linux,memory-limit property, so that the vmcore can be limited to the memory limit. The prom_init seems to export this value in the same node. But doesn't really appear there. Also the memory_limit gets adjusted with the processing of crashkernel= parameter. This patch makes sure we get the actual limit. The kexec-tools will use the value to limit the 'end' of the memory regions. Tested this patch on ppc64 and ppc32(ppc440) with a kexec-tools patch by Mahesh. Signed-off-by: Suzuki K. Poulose Tested-by: Mahesh J. Salgaonkar Signed-off-by: Benjamin Herrenschmidt --- Reading git-diff-tree failed