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Diffstat (limited to 'target/i386/fpu_helper.c')
-rw-r--r--target/i386/fpu_helper.c60
1 files changed, 54 insertions, 6 deletions
diff --git a/target/i386/fpu_helper.c b/target/i386/fpu_helper.c
index 005f1f68f8..99f28f267f 100644
--- a/target/i386/fpu_helper.c
+++ b/target/i386/fpu_helper.c
@@ -26,6 +26,10 @@
#include "exec/cpu_ldst.h"
#include "fpu/softfloat.h"
+#ifdef CONFIG_SOFTMMU
+#include "hw/irq.h"
+#endif
+
#define FPU_RC_MASK 0xc00
#define FPU_RC_NEAR 0x000
#define FPU_RC_DOWN 0x400
@@ -58,6 +62,36 @@
#define floatx80_l2e make_floatx80(0x3fff, 0xb8aa3b295c17f0bcLL)
#define floatx80_l2t make_floatx80(0x4000, 0xd49a784bcd1b8afeLL)
+#if !defined(CONFIG_USER_ONLY)
+static qemu_irq ferr_irq;
+
+void x86_register_ferr_irq(qemu_irq irq)
+{
+ ferr_irq = irq;
+}
+
+static void cpu_clear_ignne(void)
+{
+ CPUX86State *env = &X86_CPU(first_cpu)->env;
+ env->hflags2 &= ~HF2_IGNNE_MASK;
+}
+
+void cpu_set_ignne(void)
+{
+ 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
+
+
static inline void fpush(CPUX86State *env)
{
env->fpstt = (env->fpstt - 1) & 7;
@@ -136,8 +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(env);
+ else if (ferr_irq && !(env->hflags2 & HF2_IGNNE_MASK)) {
+ qemu_irq_raise(ferr_irq);
}
#endif
}
@@ -1029,6 +1063,22 @@ void helper_fstenv(CPUX86State *env, target_ulong ptr, int data32)
do_fstenv(env, ptr, data32, GETPC());
}
+static void cpu_set_fpus(CPUX86State *env, uint16_t fpus)
+{
+ env->fpstt = (fpus >> 11) & 7;
+ 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,
uintptr_t retaddr)
{
@@ -1043,8 +1093,7 @@ static void do_fldenv(CPUX86State *env, target_ulong ptr, int data32,
fpus = cpu_lduw_data_ra(env, ptr + 2, retaddr);
fptag = cpu_lduw_data_ra(env, ptr + 4, retaddr);
}
- env->fpstt = (fpus >> 11) & 7;
- env->fpus = fpus & ~0x3800;
+ cpu_set_fpus(env, fpus);
for (i = 0; i < 8; i++) {
env->fptags[i] = ((fptag & 3) == 3);
fptag >>= 2;
@@ -1292,8 +1341,7 @@ static void do_xrstor_fpu(CPUX86State *env, target_ulong ptr, uintptr_t ra)
fpus = cpu_lduw_data_ra(env, ptr + XO(legacy.fsw), ra);
fptag = cpu_lduw_data_ra(env, ptr + XO(legacy.ftw), ra);
cpu_set_fpuc(env, fpuc);
- env->fpstt = (fpus >> 11) & 7;
- env->fpus = fpus & ~0x3800;
+ cpu_set_fpus(env, fpus);
fptag ^= 0xff;
for (i = 0; i < 8; i++) {
env->fptags[i] = ((fptag >> i) & 1);