mb/google/nissa: Add fmd file for nissa

Nissa boards are curretly using chromeos.fmd file of brya. The SPI flash
layout for brya is of 32MB size, and nissa is expected to have 16MB SPI
NOR flash. The current composition of AP firmware exceeds 16MB. To get
an estimate of the unutilized region in the current flash layout for
nissa, added RW_UNUSED regions. The idea is to reduce the AP firmware
size to under 16MB and to remove the RW_UNUSED regions from the final
fmd file.

Below table gives the size reduction from brya fmd to nissa fmd:

+----------------+-------------------+---------------+
|     Region     | Earlier size (KB) | New size (KB) |
+================+===================+===============+
|      SI_ME     |        5116       |      3772     |
+----------------+-------------------+---------------+
| RW_SECTION_A/B |        8192       |      4344     |
+----------------+-------------------+---------------+
|   VBLOCK_A/B   |         64        |       8       |
+----------------+-------------------+---------------+
|    ME_RW_A/B*  |        3008       |      1434     |
+----------------+-------------------+---------------+
|    RW_LEGACY   |        2048       |      1024     |
+----------------+-------------------+---------------+
|     RW_ELOG    |         16        |       4       |
+----------------+-------------------+---------------+
|   SHARED_DATA  |         8         |       4       |
+----------------+-------------------+---------------+
|   VBLOCK_DEV   |         8         |       0       |
+----------------+-------------------+---------------+
|  RW_SPD_CACHE  |         4         |       0       |
+----------------+-------------------+---------------+
|    RW_NVRAM    |         24        |       8       |
+----------------+-------------------+---------------+
|      WP_RO     |        8192       |      4096     |
+----------------+-------------------+---------------+
|       GBB      |        448        |       12      |
+----------------+-------------------+---------------+

*Based on LZMA compression on ME_RW_A/B regions. With LZMA compression,
this region can be 1434K. Without this, ~665K will be more in each of
these regions.
Patch: https://review.coreboot.org/c/coreboot/+/62358/

BUG=b:202783191
BRANCH=None
TEST=Build and boot Nivviks.

Cq-Depend: chrome-internal:4584911
Change-Id: I24b1c19cb71a54fc916a12668f72193f9689e755
Signed-off-by: Krishna Prasad Bhat <krishna.p.bhat.d@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62372
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kangheui Won <khwon@chromium.org>
Reviewed-by: Reka Norman <rekanorman@chromium.org>

0 files changed, 0 insertions, 0 deletions