On Mon, Jun 29, 2015 at 10:53:29AM +0200, Gerd Hoffmann wrote:
Add macros to read/write registers of virtio-1.0 regions.
Signed-off-by: Gerd Hoffmann kraxel@redhat.com
src/hw/virtio-pci.h | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+)
diff --git a/src/hw/virtio-pci.h b/src/hw/virtio-pci.h index 893a7dd..e1d8b3e 100644 --- a/src/hw/virtio-pci.h +++ b/src/hw/virtio-pci.h @@ -111,6 +111,82 @@ struct vp_device { struct vp_cap common, notify, isr, device; };
+#define vp_modern_read(_cap, _struct, _field, _var) { \
u32 addr = _cap.addr; \addr += offsetof(_struct, _field); \
Wouldn't this make more sense if the bulk of the code was in a function?
That is, something like:
extern u32 _vp_modern_read(struct vp_cap *cap, u32 offset, u8 size);
#define vp_modern_read(_cap, _struct, _field, _var) { \ _var = _vp_modern_read(&_cap, offsetof(_struct, _field), sizeof((_struct *)0)->_field)
if (_cap.is_io) { \switch (sizeof(((_struct *)0)->_field)) { \case 8: \_var = inl(addr); \_var |= (u64)inl(addr+4) << 32; \break; \
It didn't look like there were any 64bit fields defined, but maybe I missed something.
BTW, last I checked, gcc didn't do a good job with code generation when shifting 64bit values on a 32bit architecture. Using unions (eg, compiler.h:union u64_u32_u) seemed to produce better code. (Though, not worth bothering with if you want to use the same code in other projects.)
-Kevin