libqos: Add 64-bit PCI IO accessors

Currently the libqos PCI layer includes accessor helpers for 8, 16 and 32
bit reads and writes.  It's likely that we'll want 64-bit accesses in the
future (plenty of modern peripherals will have 64-bit reigsters).  This
adds them.

For PIO (not MMIO) accesses on the PC backend, this is implemented as two
32-bit ins or outs.  That's not ideal but AFAICT x86 doesn't have 64-bit
versions of in and out.

This patch also converts the single current user of 64-bit accesses -
virtio-pci.c to use the new mechanism, rather than a sequence of 8 byte
reads.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>

1 files changed, 4 insertions, 12 deletions

diff --git a/tests/libqos/virtio-pci.c b/tests/libqos/virtio-pci.c
index fa82132ab7..c69d09ddb2 100644
--- a/tests/libqos/virtio-pci.c
+++ b/tests/libqos/virtio-pci.c
@@ -106,22 +106,14 @@ static uint32_t qvirtio_pci_config_readl(QVirtioDevice *d, uint64_t off)
 static uint64_t qvirtio_pci_config_readq(QVirtioDevice *d, uint64_t off)
 {
     QVirtioPCIDevice *dev = (QVirtioPCIDevice *)d;
-    int i;
-    uint64_t u64 = 0;
+    uint64_t val;
 
+    val = qpci_io_readq(dev->pdev, CONFIG_BASE(dev) + off);
     if (qvirtio_is_big_endian(d)) {
-        for (i = 0; i < 8; ++i) {
-            u64 |= (uint64_t)qpci_io_readb(dev->pdev, CONFIG_BASE(dev)
-                                           + off + i) << (7 - i) * 8;
-        }
-    } else {
-        for (i = 0; i < 8; ++i) {
-            u64 |= (uint64_t)qpci_io_readb(dev->pdev, CONFIG_BASE(dev)
-                                           + off + i) << i * 8;
-        }
+        val = bswap64(val);
     }
 
-    return u64;
+    return val;
 }
 
 static uint32_t qvirtio_pci_get_features(QVirtioDevice *d)