[Qemu-devel] [PATCH v5 2/3] 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.

Signed-off-by: Aleksandr Bezzubikov <zuban32s@gmail.com>
---
 src/fw/dev-pci.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 src/fw/dev-pci.h

diff --git a/src/fw/dev-pci.h b/src/fw/dev-pci.h
new file mode 100644
index 0000000..cf16b2e
--- /dev/null
+++ b/src/fw/dev-pci.h
@@ -0,0 +1,52 @@
+#ifndef _PCI_CAP_H
+#define _PCI_CAP_H
+
+#include "types.h"
+
+/*
+ *
+ * QEMU-specific vendor(Red Hat)-specific capability.
+ * It's intended to provide some hints for firmware to init PCI devices.
+ *
+ * Its structure is shown below:
+ *
+ * Header:
+ *
+ * u8 id;       Standard PCI Capability Header field
+ * u8 next;     Standard PCI Capability Header field
+ * u8 len;      Standard PCI Capability Header field
+ * u8 type;     Red Hat vendor-specific capability type
+ * Data:
+ *
+ * u32 bus_res;     minimum bus number to reserve;
+ *                  this is necessary for PCI Express Root Ports
+ *                  to support PCI bridges hotplug
+ * u64 io;          IO space to reserve
+ * u32 mem;         non-prefetchable memory to reserve
+ *
+ * this two fields are mutually exclusive:
+ * u32 prefetchable_mem_32;     prefetchable memory to reserve (32-bit MMIO)
+ * u64 prefetchable_mem_64;     prefetchable memory to reserve (64-bit MMIO)
+ *
+ *
+ * If any field value in Data section is 0xFF...F,
+ * it means that such kind of reservation is not needed and must be ignored.
+ *
+*/
+
+/* Offset of vendor-specific capability type field */
+#define PCI_CAP_REDHAT_TYPE_OFFSET  3
+
+/* List of valid Red Hat vendor-specific capability types */
+#define REDHAT_CAP_RESOURCE_RESERVE    1
+
+
+/* Offsets of RESOURCE_RESERVE capability fields */
+#define RES_RESERVE_BUS_RES        4
+#define RES_RESERVE_IO             8
+#define RES_RESERVE_MEM            16
+#define RES_RESERVE_PREF_MEM_32    20
+#define RES_RESERVE_PREF_MEM_64    24
+#define RES_RESERVE_CAP_SIZE       32
+
+#endif /* _PCI_CAP_H */
-- 
2.7.4