target/arm: Factor out code for setting MTE TCF0 field

Factor out the code used for setting the MTE TCF0 field from the prctl
code into a convenient function. Other subsystems, like gdbstub, need to
set this field as well, so keep it as a separate function to avoid
duplication and ensure consistency in how this field is set across the
board.

Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Message-Id: <20240628050850.536447-7-gustavo.romero@linaro.org>
[AJB: clean-up includes, move MTE defines]
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240705084047.857176-36-alex.bennee@linaro.org>

1 files changed, 2 insertions, 20 deletions

diff --git a/linux-user/aarch64/target_prctl.h b/linux-user/aarch64/target_prctl.h
index aa8e203c15..ed75b9e4b5 100644
--- a/linux-user/aarch64/target_prctl.h
+++ b/linux-user/aarch64/target_prctl.h
@@ -7,6 +7,7 @@
 #define AARCH64_TARGET_PRCTL_H
 
 #include "target/arm/cpu-features.h"
+#include "mte_user_helper.h"
 
 static abi_long do_prctl_sve_get_vl(CPUArchState *env)
 {
@@ -173,26 +174,7 @@ static abi_long do_prctl_set_tagged_addr_ctrl(CPUArchState *env, abi_long arg2)
     env->tagged_addr_enable = arg2 & PR_TAGGED_ADDR_ENABLE;
 
     if (cpu_isar_feature(aa64_mte, cpu)) {
-        /*
-         * Write PR_MTE_TCF to SCTLR_EL1[TCF0].
-         *
-         * The kernel has a per-cpu configuration for the sysadmin,
-         * /sys/devices/system/cpu/cpu<N>/mte_tcf_preferred,
-         * which qemu does not implement.
-         *
-         * Because there is no performance difference between the modes, and
-         * because SYNC is most useful for debugging MTE errors, choose SYNC
-         * as the preferred mode.  With this preference, and the way the API
-         * uses only two bits, there is no way for the program to select
-         * ASYMM mode.
-         */
-        unsigned tcf = 0;
-        if (arg2 & PR_MTE_TCF_SYNC) {
-            tcf = 1;
-        } else if (arg2 & PR_MTE_TCF_ASYNC) {
-            tcf = 2;
-        }
-        env->cp15.sctlr_el[1] = deposit64(env->cp15.sctlr_el[1], 38, 2, tcf);
+        arm_set_mte_tcf0(env, arg2);
 
         /*
          * Write PR_MTE_TAG to GCR_EL1[Exclude].