[PATCH] vexpress_ca9x4: Disable EFI_LOADER on this platform

[Tom Rini]

As part of upgrading to QEMU 10.0.0 we discovered that the EFI loader
tests would no longer pass CI, on this specific platform, while still
passing on real hardware. Upon further investigation it turns out that
on ARMv7 we rely on some undefined behavior with respect to enabling
unaligned access. And while this is seemingly fine on real hardware,
QEMU is now correct enough in implementation to no longer allow this. In
order to not rely on this undefined behavior we would need to implement
some MMU configuration (and then ensure proper tear-down possibly).

At the moment, the most reasonable path forward seems to be to document
this and disable the support here.

Link: https://gitlab.com/qemu-project/qemu/-/issues/2944
Signed-off-by: Tom Rini <trini at konsulko.com>
---
I believe at one point Norther was using this platform, in QEMU, for a
reference platform via EFI for using Mender. As such, this would likely
make this platform not useful anymore. I believe Ilias can better
explain what needs to be done to fix this properly but there's no one
with the available time to take care of this in the community at large,
and this is part of what's blocking updating QEMU to a newer version
that provides other platform and feature support we do want to use.
Alternatively, we could just let this platform go and remove it, if that
path makes more sense.

Cc: Josef Holzmayr <josef.holzmayr at northern.tech>
Cc: Heinrich Schuchardt <xypron.glpk at gmx.de>
Cc: Ilias Apalodimas <ilias.apalodimas at linaro.org>
---
 configs/vexpress_ca9x4_defconfig | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/configs/vexpress_ca9x4_defconfig b/configs/vexpress_ca9x4_defconfig
index 67adba437bfc..6ebb37fcf2ec 100644
--- a/configs/vexpress_ca9x4_defconfig
+++ b/configs/vexpress_ca9x4_defconfig
@@ -13,6 +13,7 @@ CONFIG_DEFAULT_DEVICE_TREE="vexpress-v2p-ca9"
 CONFIG_SYS_LOAD_ADDR=0x90000000
 CONFIG_ENV_ADDR=0x47F80000
 CONFIG_SYS_MONITOR_BASE=0x40000000
+# CONFIG_EFI_LOADER is not set
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_BOOTCOMMAND="run distro_bootcmd; run bootflash"
 CONFIG_DEFAULT_FDT_FILE="vexpress-v2p-ca9.dtb"
@@ -20,6 +21,7 @@ CONFIG_SYS_CBSIZE=512
 CONFIG_SYS_PBSIZE=532
 # CONFIG_DISPLAY_CPUINFO is not set
 # CONFIG_DISPLAY_BOARDINFO is not set
+CONFIG_LAST_STAGE_INIT=y
 # CONFIG_CMD_CONSOLE is not set
 # CONFIG_CMD_BOOTD is not set
 # CONFIG_CMD_XIMG is not set
@@ -55,4 +57,6 @@ CONFIG_SMC911X=y
 CONFIG_SMC911X_32_BIT=y
 CONFIG_BAUDRATE=38400
 CONFIG_DM_SERIAL=y
+CONFIG_FAT_WRITE=y
+CONFIG_FAT_RENAME=y
 CONFIG_SYS_TIMER_COUNTS_DOWN=y
-- 
2.43.0