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Diffstat (limited to 'target/i386/fpu_helper.c')
-rw-r--r--target/i386/fpu_helper.c34
1 files changed, 27 insertions, 7 deletions
diff --git a/target/i386/fpu_helper.c b/target/i386/fpu_helper.c
index 6825024f5c..99f28f267f 100644
--- a/target/i386/fpu_helper.c
+++ b/target/i386/fpu_helper.c
@@ -70,14 +70,24 @@ void x86_register_ferr_irq(qemu_irq irq)
ferr_irq = irq;
}
-void cpu_clear_ferr(void)
+static void cpu_clear_ignne(void)
{
- qemu_irq_lower(ferr_irq);
+ CPUX86State *env = &X86_CPU(first_cpu)->env;
+ env->hflags2 &= ~HF2_IGNNE_MASK;
}
-static void cpu_set_ferr(void)
+void cpu_set_ignne(void)
{
- qemu_irq_raise(ferr_irq);
+ CPUX86State *env = &X86_CPU(first_cpu)->env;
+ env->hflags2 |= HF2_IGNNE_MASK;
+ /*
+ * We get here in response to a write to port F0h. The chipset should
+ * deassert FP_IRQ and FERR# instead should stay signaled until FPSW_SE is
+ * cleared, because FERR# and FP_IRQ are two separate pins on real
+ * hardware. However, we don't model FERR# as a qemu_irq, so we just
+ * do directly what the chipset would do, i.e. deassert FP_IRQ.
+ */
+ qemu_irq_lower(ferr_irq);
}
#endif
@@ -160,8 +170,8 @@ static void fpu_raise_exception(CPUX86State *env, uintptr_t retaddr)
raise_exception_ra(env, EXCP10_COPR, retaddr);
}
#if !defined(CONFIG_USER_ONLY)
- else {
- cpu_set_ferr();
+ else if (ferr_irq && !(env->hflags2 & HF2_IGNNE_MASK)) {
+ qemu_irq_raise(ferr_irq);
}
#endif
}
@@ -1056,7 +1066,17 @@ void helper_fstenv(CPUX86State *env, target_ulong ptr, int data32)
static void cpu_set_fpus(CPUX86State *env, uint16_t fpus)
{
env->fpstt = (fpus >> 11) & 7;
- env->fpus = fpus & ~0x3800;
+ env->fpus = fpus & ~0x3800 & ~FPUS_B;
+ env->fpus |= env->fpus & FPUS_SE ? FPUS_B : 0;
+#if !defined(CONFIG_USER_ONLY)
+ if (!(env->fpus & FPUS_SE)) {
+ /*
+ * Here the processor deasserts FERR#; in response, the chipset deasserts
+ * IGNNE#.
+ */
+ cpu_clear_ignne();
+ }
+#endif
}
static void do_fldenv(CPUX86State *env, target_ulong ptr, int data32,