Re: [Qemu-devel] Disable interrupts on Cortex M3 (lm3s6965evb)

[Sebastian Huber <sebastian.huber@embedded-brains.de>]

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On 05/06/11 12:31, Sebastian Huber wrote:
> Hello,
>
> how can I disable interrupts on the Cortex M3 based board LM3S6965EVB?
> Even if I set PRIMASK, FAULTMASK and BASEPRI to 1 the SYSTICK interrupt
> handler gets called.
>
> Have a nice day!
>   

I think the interrupt handling logic for ARMv7M is wrong in cpu-exec.c
line 470.  Please have a look at the attached patch.

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>From b424c34d0202950307b3a12778a06834917b2947 Mon Sep 17 00:00:00 2001
From: Sebastian Huber <sebastian.huber@embedded-brains.de>
Date: Sun, 5 Jun 2011 14:57:17 +0200
Subject: [PATCH] Fixed interrupt handling for ARMv7M.

---
 cpu-exec.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/cpu-exec.c b/cpu-exec.c
index 6ddd8dd..2782076 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -470,8 +470,8 @@ int cpu_exec(CPUState *env1)
                        We avoid this by disabling interrupts when
                        pc contains a magic address.  */
                     if (interrupt_request & CPU_INTERRUPT_HARD
-                        && ((IS_M(env) && env->regs[15] < 0xfffffff0)
-                            || !(env->uncached_cpsr & CPSR_I))) {
+                        && !(env->uncached_cpsr & CPSR_I)
+                        && (IS_M(env) && env->regs[15] < 0xfffffff0)) {
                         env->exception_index = EXCP_IRQ;
                         do_interrupt(env);
                         next_tb = 0;
-- 
1.7.1