SH_EXT_EXIT_EXTENDED is a v2.0 semihosting extension: it
indicates that the implementation supports the SYS_EXIT_EXTENDED
function. This function allows both A64 and A32/T32 guests to
exit with a specified exit status, unlike the older SYS_EXIT
function which only allowed this for A64 guests. Implement
this extension.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
target/arm/arm-semi.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
index 0df8d4d69d6..3900bd4e1e6 100644
--- a/target/arm/arm-semi.c
+++ b/target/arm/arm-semi.c
@@ -66,6 +66,7 @@ typedef void TaskState;
#define TARGET_SYS_HEAPINFO 0x16
#define TARGET_SYS_EXIT 0x18
#define TARGET_SYS_SYNCCACHE 0x19
+#define TARGET_SYS_EXIT_EXTENDED 0x20
/* ADP_Stopped_ApplicationExit is used for exit(0),
* anything else is implemented as exit(1) */
@@ -485,7 +486,7 @@ static const uint8_t featurefile_data[] = {
SHFB_MAGIC_1,
SHFB_MAGIC_2,
SHFB_MAGIC_3,
- SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
+ SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
};
static void init_featurefile_guestfd(int guestfd)
@@ -1026,11 +1027,14 @@ target_ulong do_arm_semihosting(CPUARMState *env)
return 0;
}
case TARGET_SYS_EXIT:
- if (is_a64(env)) {
+ case TARGET_SYS_EXIT_EXTENDED:
+ if (nr == TARGET_SYS_EXIT_EXTENDED || is_a64(env)) {
/*
- * The A64 version of this call takes a parameter block,
+ * The A64 version of SYS_EXIT takes a parameter block,
* so the application-exit type can return a subcode which
* is the exit status code from the application.
+ * SYS_EXIT_EXTENDED is an a new-in-v2.0 optional function
+ * which allows A32/T32 guests to also provide a status code.
*/
GET_ARG(0);
GET_ARG(1);
@@ -1042,8 +1046,10 @@ target_ulong do_arm_semihosting(CPUARMState *env)
}
} else {
/*
- * ARM specifies only Stopped_ApplicationExit as normal
- * exit, everything else is considered an error
+ * The A32/T32 version of SYS_EXIT specifies only
+ * Stopped_ApplicationExit as normal exit, but does not
+ * allow the guest to specify the exit status code.
+ * Everything else is considered an error.
*/
ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
}
--
2.20.1
