[Slof] [PATCH 4/5] cas: Increase FDT buffer size to accomodate larger ibm, cas node properties

Nikunj A Dadhania nikunj at linux.vnet.ibm.com
Mon Jul 6 21:11:50 AEST 2015

From: Bharata B Rao <bharata at linux.vnet.ibm.com>

When QEMU starts with a higher value of maxmem, ibm,dynamic-memory
property under ibm,client-architecture-support device tree node can
consume a large FDT buffer space.

Accommodate this by increasing the FDT buffer size passed from SLOF
to QEMU to 128KB from the current 32KB.

Tested with QEMU options:
"-m 2G,slots=16,maxmem=1024G -smp 255 -cpu host,compat=power7"
on a POWER8 host with /sys/devices/system/cpu/subcores_per_core=4

Signed-off-by: Bharata B Rao <bharata at linux.vnet.ibm.com>
Cc: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
 slof/fs/archsupport.fs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/slof/fs/archsupport.fs b/slof/fs/archsupport.fs
index cc46687..f564ab4 100644
--- a/slof/fs/archsupport.fs
+++ b/slof/fs/archsupport.fs
@@ -10,9 +10,9 @@
 \ *     IBM Corporation - initial implementation
 \ ****************************************************************************/
-\ Qemu supports max 256cpus, 32K will be able to accomodate the fdt changes if
-\ needed.
-8000 VALUE size
+\ 128KB FDT buffer size is enough to accommodate 255 CPU cores and 1TB of
+\ maxmem specification.
+20000 VALUE size
 : ibm,client-architecture-support         ( vec -- err? )
     \ Store require parameters in nvram
     \ to come back to right boot device

More information about the SLOF mailing list