mainboard/emulation/qemu-sbsa: Add qemu-sbsa board

Add coreboot support for qemu's sbsa-ref (Server Base System
Architecture) machine (-m sbsa-ref).

The qemu-sbsa coreboot port runs on EL2 and is the payload of the
EL3 firmware (Arm Trusted Firmware).

Note that, coreboot expects a pointer to the FDT in x0. Make sure
to configure TF-A to handoff the FDT pointer.

Example qemu commandline:

  qemu-system-aarch64 -nographic -m 2048 -M sbsa-ref \
                      -pflash <path/to/TFA.fd> \
                      -pflash <path/to/coreboot.rom>

The Documentation can be found here:
Documentation/mainboard/emulation/qemu-sbsa.md

Change-Id: Iacc9aaf065e0d153336cbef9a9b5b46a9eb24a53
Signed-off-by: David Milosevic <David.Milosevic@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79086
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Lean Sheng Tan <sheng.tan@9elements.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/src/mainboard/emulation/qemu-sbsa/flash.fmd b/src/mainboard/emulation/qemu-sbsa/flash.fmd
new file mode 100644
index 0000000000..fcc6e19a99
--- /dev/null
+++ b/src/mainboard/emulation/qemu-sbsa/flash.fmd
@@ -0,0 +1,23 @@
+#
+# custom fmap which takes the additional TF-A region into account
+#
+# +-------------+ <-- 0x0
+# |    TF-A     |
+# +-------------+ <-- BIOS_BASE
+# |  bootblock  |
+# +-------------+ <-- BIOS_BASE + 128K
+# |    FMAP     |
+# +-------------+ <-- BIOS_BASE + 128K + FMAP_SIZE
+# |    CBFS     |
+# +-------------+ <-- ROM_SIZE
+#
+
+FLASH@0x10000000 CONFIG_ROM_SIZE {
+
+	BIOS {
+
+		BOOTBLOCK 128K
+		FMAP 0x200
+		COREBOOT(CBFS)
+	}
+}