Increase default size of UBI read-write volume

The default size of the UBI read-write volume is currently set to 4MB.
There are no plans to store more than one BMC rootfs image on the chip
so in a 32MB flash chip, accounting for the current rootfs image size
of ~15MB with plans to grow to ~20MB with the addition of redfish and
other packages, it is safe to increase the read-write volume size to
6MB since the current size is already almost completely taken up if
there are multiple error logs / dumps on the system.

In addition, make the size configurable from a recipe so that the
size can be changed in a per-system basis. And during code update,
check the current size and update it if it's different, this allows
systems to be able to be resized to a new size by performing factory
reset after a code update that sets the new size.

Tested:
- Booted on QEMU and verified non-ubi system (romulus) retains the
current 4MB read-write volume, and ubi system (witherspoon) has a
6MB volume.
- Code updated to an image that has these changes and verified the
rwfs_size env variable changes to 6MB, and that a subsequent factory
reset rebuilds the volume with size 6MB.

Change-Id: I995eb560c1bd87ee95712c731e3d6e55bc0b2735
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/meta-phosphor/classes/image_types_phosphor.bbclass b/meta-phosphor/classes/image_types_phosphor.bbclass
index 5599332f6..35843ea81 100644
--- a/meta-phosphor/classes/image_types_phosphor.bbclass
+++ b/meta-phosphor/classes/image_types_phosphor.bbclass
@@ -52,8 +52,8 @@ FLASH_ROFS_OFFSET ?= "4864"
 FLASH_RWFS_OFFSET ?= "28672"
 
 # UBI volume sizes in KB unless otherwise noted.
-FLASH_UBI_RWFS_SIZE ?= "4096"
-FLASH_UBI_RWFS_TXT_SIZE ?= "4MiB"
+FLASH_UBI_RWFS_SIZE ?= "6144"
+FLASH_UBI_RWFS_TXT_SIZE ?= "6MiB"
 
 python() {
     # Compute rwfs LEB count and LEB size.