Commit 73479c5c authored by Aurelien Jarno's avatar Aurelien Jarno
Browse files

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: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarAurelien Jarno <aurelien@aurel32.net>
parent 324189ba

target/sh4/helper.c

+9 −1
Original line number Diff line number Diff line
@@ -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 @@ void superh_cpu_do_interrupt(CPUState *cs) 


    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 */