meta-zephyr-sdk: xilinx_qemu: Fix qemu WFI behavior

As has been described by Stephanos in the commit message
tests/kernel/context is broken when these two patches are not applied
that's why get them back to have clean CI loop.

Issue can be replicated by running
west twister -v -p qemu_cortex_r5 -O /tmp/twister -T tests/kernel/context/

Signed-off-by: Michal Simek <michal.simek@amd.com>

Author: michalsimek

meta-zephyr-sdk/recipes-devtools/qemu_xilinx/files/0001-Revert-target-arm-Revert-back-to-YIELD-for-WFI.patch

@@ -0,0 +1,40 @@
+From ab42d46c10d4e24cd19fb3339fc2738ba7b4a45e Mon Sep 17 00:00:00 2001
+Message-ID: <ab42d46c10d4e24cd19fb3339fc2738ba7b4a45e.1747662482.git.michal.simek@amd.com>
+From: Stephanos Ioannidis <root@stephanos.io>
+Date: Wed, 8 Jan 2020 17:47:05 +0900
+Subject: [PATCH] Revert "target/arm: Revert back to YIELD for WFI"
+
+This reverts commit 5f38ea92fb697b94ad43f01fe162f3ed6e6b0e16.
+
+The commit 5f38ea92fb697b94ad43f01fe162f3ed6e6b0e16 was probably
+introduced in order to improve emulation performance, as well as to
+address the stability issue when running co-simulations (refer to the
+commit 708639f72be2a9425992ae9dc4b9a098dc804c94).
+
+This, unfortunately, breaks the WFI instruction; i.e. CPU is not halted
+and keeps running regardless of whether an interrupt occurs, and this
+is a problem for the Zephyr CI tests that expect the WFI instruction to
+do its job (in particular, tests/kernel/context is broken because of
+this change).
+
+Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
+---
+ target/arm/tcg/op_helper.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/target/arm/tcg/op_helper.c b/target/arm/tcg/op_helper.c
+index 1e9ff35f0c30..67add5c6973c 100644
+--- a/target/arm/tcg/op_helper.c
++++ b/target/arm/tcg/op_helper.c
+@@ -353,7 +353,7 @@ void HELPER(wfi)(CPUARMState *env, uint32_t insn_len)
+     }
+ 
+     qemu_mutex_lock_iothread();
+-    if (use_icount || 1) {
++    if (use_icount) {
+         cs->exception_index = EXCP_YIELD;
+     } else {
+         cs->halted = 1;
+-- 
+2.43.0
+

meta-zephyr-sdk/recipes-devtools/qemu_xilinx/files/0002-Enable-WFI-CPU-halting-in-icount-mode.patch

@@ -0,0 +1,39 @@
+From 393c4e5f40fb4592b3cf8247feee73538f541437 Mon Sep 17 00:00:00 2001
+Message-ID: <393c4e5f40fb4592b3cf8247feee73538f541437.1747662482.git.michal.simek@amd.com>
+From: Stephanos Ioannidis <root@stephanos.io>
+Date: Wed, 26 Feb 2020 12:30:55 +0900
+Subject: [PATCH] Enable WFI CPU halting in icount mode
+
+This commit enables CPU halting via the WFI instruction in the
+icount mode.
+
+The PetaLinux patch initially disabled WFI CPU halting, possibly for
+performance reasons.
+
+Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
+---
+ target/arm/tcg/op_helper.c | 8 ++------
+ 1 file changed, 2 insertions(+), 6 deletions(-)
+
+diff --git a/target/arm/tcg/op_helper.c b/target/arm/tcg/op_helper.c
+index 67add5c6973c..f76c6eb5484e 100644
+--- a/target/arm/tcg/op_helper.c
++++ b/target/arm/tcg/op_helper.c
+@@ -353,12 +353,8 @@ void HELPER(wfi)(CPUARMState *env, uint32_t insn_len)
+     }
+ 
+     qemu_mutex_lock_iothread();
+-    if (use_icount) {
+-        cs->exception_index = EXCP_YIELD;
+-    } else {
+-        cs->halted = 1;
+-        cs->exception_index = EXCP_HLT;
+-    }
++    cs->halted = 1;
++    cs->exception_index = EXCP_HLT;
+ 
+     /* Drive STANDBYWFI only if cpu reset-pin is inactive */
+     if (cs->reset_pin == false) {
+-- 
+2.43.0
+

meta-zephyr-sdk/recipes-devtools/qemu_xilinx/qemu-xilinx_git.bb

@@ -12,6 +12,8 @@ SRCREV_FORMAT = "qemu"
 SRC_URI += "gitsm://github.com/Xilinx/qemu.git;protocol=https;nobranch=1;name=qemu \
            file://cross.patch \
            file://0004-configure-Add-pkg-config-handling-for-libgcrypt.patch \
+           file://0001-Revert-target-arm-Revert-back-to-YIELD-for-WFI.patch \
+           file://0002-Enable-WFI-CPU-halting-in-icount-mode.patch \
            file://0008-tests-meson.build-use-relative-path-to-refer-to-file.patch \
            file://fixedmeson.patch \
            file://no-pip.patch \