1 files changed, 50 insertions, 0 deletions
diff --git a/meta-arm/meta-arm-bsp/recipes-bsp/trusted-firmware-m/files/corstone1000/0009-platform-corstone1000-fix-synchronization-issue-on-o.patch b/meta-arm/meta-arm-bsp/recipes-bsp/trusted-firmware-m/files/corstone1000/0009-platform-corstone1000-fix-synchronization-issue-on-o.patch
new file mode 100644
index 0000000000..be6bde6f8a
--- /dev/null
+++ b/meta-arm/meta-arm-bsp/recipes-bsp/trusted-firmware-m/files/corstone1000/0009-platform-corstone1000-fix-synchronization-issue-on-o.patch
@@ -0,0 +1,50 @@
+From b70dd14eed59d7c5833ded8469cf99e631951e14 Mon Sep 17 00:00:00 2001
+From: Emekcan Aras <emekcan.aras@arm.com>
+Date: Wed, 15 Nov 2023 09:52:19 +0000
+Subject: [PATCH] platform: corstone1000: fix synchronization issue on openamp
+ notification
+
+This fixes a race that is observed rarely in the FVP. It occurs in FVP
+when tfm sends the notication ack in openamp, and then reset the access
+request which resets the mhu registers before received by the host
+processor. This solution introduces polling on the status register of
+mhu until the notificaiton is read by the host processor. (Inspired by
+signal_and_wait_for_signal function in mhu_wrapper_v2_x.c in trusted-firmware-m
+https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git/tree/platform/ext/target/arm/rss/common/native_drivers/mhu_wrapper_v2_x.c#n61)
+
+Signed-off-by: Emekcan Aras <emekcan.aras@arm.com>
+Upstream-Status: Pending [Not submitted to upstream yet]
+---
+ .../corstone1000/openamp/platform_spe_dual_core_hal.c    | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/platform/ext/target/arm/corstone1000/openamp/platform_spe_dual_core_hal.c b/platform/ext/target/arm/corstone1000/openamp/platform_spe_dual_core_hal.c
+index 7613345ffc..b58088032f 100644
+--- a/platform/ext/target/arm/corstone1000/openamp/platform_spe_dual_core_hal.c
++++ b/platform/ext/target/arm/corstone1000/openamp/platform_spe_dual_core_hal.c
+@@ -83,7 +83,7 @@ enum tfm_plat_err_t tfm_dual_core_hal_init(void)
+
+ enum tfm_plat_err_t tfm_hal_notify_peer(void)
+ {
+-    uint32_t access_ready;
++    uint32_t access_ready,val;
+     enum mhu_v2_x_error_t status;
+     struct mhu_v2_x_dev_t* dev = &MHU1_SE_TO_HOST_DEV;
+
+@@ -108,6 +108,13 @@ enum tfm_plat_err_t tfm_hal_notify_peer(void)
+         return TFM_PLAT_ERR_SYSTEM_ERR;
+     }
+
++    do {
++        status = mhu_v2_x_channel_poll(dev, MHU1_SEH_NOTIFY_CH, &val);
++        if (status != MHU_V_2_X_ERR_NONE) {
++            break;
++        }
++    } while(val != 0);
++
+     status = mhu_v2_x_reset_access_request(dev);
+     if (status != MHU_V_2_X_ERR_NONE) {
+         SPMLOG_ERRMSGVAL("mhu_v2_x_reset_access_request : ", status);
+--
+2.25.1
+