uapi/linux/pci_regs.h defines Primary/Secondary/Subordinate Bus Numbers
and Secondary Latency Timer (PCIe r7.0, sec. 7.5.1.3) as byte register
offsets but in practice the code may read/write the entire dword. In the
lack of defines to handle the dword fields, the code ends up using
literals which are not as easy to read.
Add dword field masks for the Bus Number and Secondary Latency Timer
fields.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
include/uapi/linux/pci_regs.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 3add74ae2594..8be55ece2a21 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -132,6 +132,11 @@
#define PCI_SECONDARY_BUS 0x19 /* Secondary bus number */
#define PCI_SUBORDINATE_BUS 0x1a /* Highest bus number behind the bridge */
#define PCI_SEC_LATENCY_TIMER 0x1b /* Latency timer for secondary interface */
+/* Masks for dword-sized processing of Bus Number and Sec Latency Timer fields */
+#define PCI_PRIMARY_BUS_MASK 0x000000ff
+#define PCI_SECONDARY_BUS_MASK 0x0000ff00
+#define PCI_SUBORDINATE_BUS_MASK 0x00ff0000
+#define PCI_SEC_LATENCY_TIMER_MASK 0xff000000
#define PCI_IO_BASE 0x1c /* I/O range behind the bridge */
#define PCI_IO_LIMIT 0x1d
#define PCI_IO_RANGE_TYPE_MASK 0x0fUL /* I/O bridging type */
--
2.39.5