target/sh4: fix reset when using a kernel and an initrd
When a masked exception happens, the SH4 CPU generates a non-masked
reset exception, which then jumps to the reset vector at address
0xA0000000. While this is emulated correctly in QEMU, this does not
work when using a kernel and initrd as this address then contain an
illegal instruction (and there is no guarantee the kernel and initrd
haven't been overwritten).
Therefore call qemu_system_reset_request to reload the kernel and initrd
and load the program counter to the kernel entry point.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
diff --git a/target/sh4/helper.c b/target/sh4/helper.c
index 4c024f9..16fcd1b 100644
--- a/target/sh4/helper.c
+++ b/target/sh4/helper.c
@@ -21,6 +21,7 @@
#include "cpu.h"
#include "exec/exec-all.h"
#include "exec/log.h"
+#include "sysemu/sysemu.h"
#if !defined(CONFIG_USER_ONLY)
#include "hw/sh4/sh_intc.h"
@@ -92,7 +93,14 @@
if (env->sr & (1u << SR_BL)) {
if (do_exp && cs->exception_index != 0x1e0) {
- cs->exception_index = 0x000; /* masked exception -> reset */
+ /* In theory a masked exception generates a reset exception,
+ which in turn jumps to the reset vector. However this only
+ works when using a bootloader. When using a kernel and an
+ initrd, they need to be reloaded and the program counter
+ should be loaded with the kernel entry point.
+ qemu_system_reset_request takes care of that. */
+ qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+ return;
}
if (do_irq && !env->in_sleep) {
return; /* masked */
