[PATCH v12 2/4] selftests/vfio: Add generic PCI command register helpers

[Rubin Du <rubind@nvidia.com>]

Add vfio_pci_cmd_set()/vfio_pci_cmd_clear() read-modify-write macros
for PCI_COMMAND in vfio_pci_device.h.

Signed-off-by: Rubin Du <rubind@nvidia.com>
---
 .../vfio/lib/include/libvfio/vfio_pci_device.h         | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
index 2858885a89bb..e5e290eed510 100644
--- a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
+++ b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
@@ -65,6 +65,16 @@ void vfio_pci_config_access(struct vfio_pci_device *device, bool write,
 #define vfio_pci_config_writew(_d, _o, _v) vfio_pci_config_write(_d, _o, _v, u16)
 #define vfio_pci_config_writel(_d, _o, _v) vfio_pci_config_write(_d, _o, _v, u32)
 
+#define vfio_pci_cmd_set(_device, _bits) do {				\
+	u16 __cmd = vfio_pci_config_readw((_device), PCI_COMMAND);	\
+	vfio_pci_config_writew((_device), PCI_COMMAND, __cmd | (_bits));\
+} while (0)
+
+#define vfio_pci_cmd_clear(_device, _bits) do {				\
+	u16 __cmd = vfio_pci_config_readw((_device), PCI_COMMAND);	\
+	vfio_pci_config_writew((_device), PCI_COMMAND, __cmd & ~(_bits));\
+} while (0)
+
 void vfio_pci_irq_enable(struct vfio_pci_device *device, u32 index,
 			 u32 vector, int count);
 void vfio_pci_irq_disable(struct vfio_pci_device *device, u32 index);
-- 
2.43.0