From 038895cb103127e0eaaf1f6242f95cf16187d7d9 Mon Sep 17 00:00:00 2001
From: Ricardo Salveti <ricardo.salveti@oss.qualcomm.com>
Date: Thu, 18 Jun 2026 00:17:01 -0300
Subject: [PATCH] u-boot-qcom: enable EFI runtime variable store for efivar

Enable CONFIG_EFI_RT_VOLATILE_STORE so U-Boot supports SetVariable at
runtime on its in-RAM EFI variable backend. With this U-Boot advertises
EFI_RT_SUPPORTED_SET_VARIABLE in the RT properties table and creates the
RTStorageVolatile and VarToFile EFI variables.

These variables are what userspace needs to persist runtime EFI variable
changes: RTStorageVolatile names the variable store file relative to the
ESP (ubootefi.var) and VarToFile holds the binary dump of the variables
to write back. The efivar SetVariableRT backport in oe-core uses them to
sync changes to the ESP so they survive reboots; without this option
SetVariable at runtime returns EFI_UNSUPPORTED and efivar cannot work.

CONFIG_EFI_RT_VOLATILE_STORE depends on CONFIG_EFI_VARIABLE_FILE_STORE,
so select that explicitly in the fragment to keep the option from being
silently dropped should the dependency default ever change.

Signed-off-by: Ricardo Salveti <ricardo.salveti@oss.qualcomm.com>
---
 recipes-bsp/u-boot/files/efi-rt-volatile-store.cfg | 10 ++++++++++
 recipes-bsp/u-boot/u-boot-qcom_git.bb              |  1 +
 2 files changed, 11 insertions(+)
 create mode 100644 recipes-bsp/u-boot/files/efi-rt-volatile-store.cfg

diff --git a/recipes-bsp/u-boot/files/efi-rt-volatile-store.cfg b/recipes-bsp/u-boot/files/efi-rt-volatile-store.cfg
new file mode 100644
index 000000000..082159b32
--- /dev/null
+++ b/recipes-bsp/u-boot/files/efi-rt-volatile-store.cfg
@@ -0,0 +1,10 @@
+# Allow SetVariable at runtime on U-Boot's in-RAM EFI variable store so the
+# OS can write EFI variables via efivarfs. With this enabled U-Boot also
+# advertises EFI_RT_SUPPORTED_SET_VARIABLE and exposes the RTStorageVolatile
+# and VarToFile variables, which userspace tools such as efivar use to persist
+# runtime changes back to the ubootefi.var store on the ESP across reboots.
+#
+# EFI_RT_VOLATILE_STORE depends on EFI_VARIABLE_FILE_STORE; select it
+# explicitly so the option is not silently dropped if that default changes.
+CONFIG_EFI_VARIABLE_FILE_STORE=y
+CONFIG_EFI_RT_VOLATILE_STORE=y
diff --git a/recipes-bsp/u-boot/u-boot-qcom_git.bb b/recipes-bsp/u-boot/u-boot-qcom_git.bb
index 3f83fa532..9e9981bd3 100644
--- a/recipes-bsp/u-boot/u-boot-qcom_git.bb
+++ b/recipes-bsp/u-boot/u-boot-qcom_git.bb
@@ -13,6 +13,7 @@ SRCBRANCH = "nobranch=1"
 SRC_URI = "git://github.com/qualcomm-linux/u-boot.git;${SRCBRANCH};protocol=https;name=uboot"
 SRC_URI += " \
     file://disable-eficapsule-tool.cfg \
+    file://efi-rt-volatile-store.cfg \
     ${@bb.utils.contains('MACHINE_FEATURES', 'optee', 'file://tfa-optee.cfg', '', d)} \
     ${@bb.utils.contains('MACHINE_FEATURES', 'kvm', 'file://gunyah-exit.cfg', '', d)} \
 "