[Qemu-devel] [RFC PATCH v2 3/4] pci: add QEMU-specific PCI capability structure

[Aleksandr Bezzubikov <zuban32s@gmail.com>]

On PCI init PCI bridge devices may need some
extra info about bus number to reserve, IO, memory and
prefetchable memory limits. QEMU can provide this
with special vendor-specific PCI capability.

This capability is intended to be used only
for Red Hat PCI bridges, i.e. QEMU cooperation.

Sizes of limits match ones from 
PCI Type 1 Configuration Space Header,
number of buses to reserve occupies only 1 byte 
since it is the size of Subordinate Bus Number register.

Signed-off-by: Aleksandr Bezzubikov <zuban32s@gmail.com>
---
 src/hw/pci_cap.h | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 src/hw/pci_cap.h

diff --git a/src/hw/pci_cap.h b/src/hw/pci_cap.h
new file mode 100644
index 0000000..1382b0b
--- /dev/null
+++ b/src/hw/pci_cap.h
@@ -0,0 +1,23 @@
+#ifndef _PCI_CAP_H
+#define _PCI_CAP_H
+
+#include "types.h"
+
+struct vendor_pci_cap {
+    u8 id;
+    u8 next;
+    u8 len;
+};
+
+struct redhat_pci_bridge_cap {
+    struct vendor_pci_cap hdr;
+    u8 bus_res;
+    u32 pref_lim_upper;
+    u16 pref_lim;
+    u16 mem_lim;
+    u16 io_lim_upper;
+    u8 io_lim;
+    u8 padd;
+};
+
+#endif /* _PCI_CAP_H */
-- 
2.7.4