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authorPaolo Bonzini <pbonzini@redhat.com>2015-01-20 17:23:48 +0100
committerGerd Hoffmann <kraxel@redhat.com>2015-01-22 11:04:18 +0100
commit9939375c282a0f97afa69dc6799d3c77aaf7d544 (patch)
tree9beb56a768f40fcdb18e56a557b7577832ef108a
parent699eae17b841e6784dc3864bf357e26bff1e9dfe (diff)
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sb16: fix interrupt acknowledgement
SoundBlaster 16 emulation is very broken and consumes a lot of CPU, but a small fix was suggested offlist and it is enough to fix some games. I got Epic Pinball to work with the "SoundBlaster Clone" option. The processing of the interrupt register is wrong due to two missing "not"s. This causes the interrupt flag to remain set even after the Acknowledge ports have been read (0x0e and 0x0f). The line was introduced by commit 85571bc (audio merge (malc), 2004-11-07), but the code might have been broken before because I did not look closely at the huge patches from 10 years ago. Reported-by: Joshua Bair <j_bair@bellsouth.net> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: qemu-stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
-rw-r--r--hw/audio/sb16.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/hw/audio/sb16.c b/hw/audio/sb16.c
index bda26d0123..444eb9e419 100644
--- a/hw/audio/sb16.c
+++ b/hw/audio/sb16.c
@@ -999,7 +999,7 @@ static IO_READ_PROTO (dsp_read)
retval = (!s->out_data_len || s->highspeed) ? 0 : 0x80;
if (s->mixer_regs[0x82] & 1) {
ack = 1;
- s->mixer_regs[0x82] &= 1;
+ s->mixer_regs[0x82] &= ~1;
qemu_irq_lower (s->pic);
}
break;
@@ -1008,7 +1008,7 @@ static IO_READ_PROTO (dsp_read)
retval = 0xff;
if (s->mixer_regs[0x82] & 2) {
ack = 1;
- s->mixer_regs[0x82] &= 2;
+ s->mixer_regs[0x82] &= ~2;
qemu_irq_lower (s->pic);
}
break;