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authorPaolo Bonzini <pbonzini@redhat.com>2015-03-30 12:49:40 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2015-04-27 18:24:19 +0200
commit147ed379838176d4780688157891c06f49403b19 (patch)
tree1ba0876adf56552be0d542712f795dd32df3f317 /ioport.c
parent30476b2282c69c9ec1e44e33a4c0b5d5f4bc884e (diff)
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ioport: loosen assertions on emulation of 16-bit ports
Right now, ioport.c assumes that the entire range specified with MemoryRegionPortio includes a region with size == 1. This however is not true for the VBE DISPI ports, which are 16-bit only. The next patch will make these regions' length equal to two, which can cause the assertions to trigger. Replace them with simple conditionals. Also, ioport.c will emulate a 16-bit ioport with two distinct reads or writes, even if one of the two accesses is out of the bounds given by the MemoryRegionPortio array. Do not do this anymore, instead discard writes to the incorrect register and read it as all-ones. This ensures that the mrp->read and mrp->write callbacks get an in-range ioport number. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'ioport.c')
-rw-r--r--ioport.c20
1 files changed, 14 insertions, 6 deletions
diff --git a/ioport.c b/ioport.c
index eb954e3..090c262 100644
--- a/ioport.c
+++ b/ioport.c
@@ -187,9 +187,14 @@ static uint64_t portio_read(void *opaque, hwaddr addr, unsigned size)
data = mrp->read(mrpio->portio_opaque, mrp->base + addr);
} else if (size == 2) {
mrp = find_portio(mrpio, addr, 1, false);
- assert(mrp);
- data = mrp->read(mrpio->portio_opaque, mrp->base + addr) |
- (mrp->read(mrpio->portio_opaque, mrp->base + addr + 1) << 8);
+ if (mrp) {
+ data = mrp->read(mrpio->portio_opaque, mrp->base + addr);
+ if (addr + 1 < mrp->offset + mrp->len) {
+ data |= mrp->read(mrpio->portio_opaque, mrp->base + addr + 1) << 8;
+ } else {
+ data |= 0xff00;
+ }
+ }
}
return data;
}
@@ -204,9 +209,12 @@ static void portio_write(void *opaque, hwaddr addr, uint64_t data,
mrp->write(mrpio->portio_opaque, mrp->base + addr, data);
} else if (size == 2) {
mrp = find_portio(mrpio, addr, 1, true);
- assert(mrp);
- mrp->write(mrpio->portio_opaque, mrp->base + addr, data & 0xff);
- mrp->write(mrpio->portio_opaque, mrp->base + addr + 1, data >> 8);
+ if (mrp) {
+ mrp->write(mrpio->portio_opaque, mrp->base + addr, data & 0xff);
+ if (addr + 1 < mrp->offset + mrp->len) {
+ mrp->write(mrpio->portio_opaque, mrp->base + addr + 1, data >> 8);
+ }
+ }
}
}