arm: a37xx: pci: Handle propagation of CRSSVE bit from PCIe Root Port

Now that PCI Bridge (PCIe Root Port) for Aardvark is emulated in U-Boot,
add support for handling and propagation of CRSSVE bit.

When CRSSVE bit is unset (default), driver has to reissue config
read/write request on CRS response.

CRSSVE bit is supported only when CRSVIS bit is provided in read-only
Root Capabilities register. So manually inject this CRSVIS bit into read
response for that register.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/include/pci.h b/include/pci.h
index 11009a2..797f224 100644
--- a/include/pci.h
+++ b/include/pci.h
@@ -495,6 +495,10 @@
 #define  PCI_EXP_LNKSTA_DLLLA	0x2000	/* Data Link Layer Link Active */
 #define PCI_EXP_SLTCAP		20	/* Slot Capabilities */
 #define  PCI_EXP_SLTCAP_PSN	0xfff80000 /* Physical Slot Number */
+#define PCI_EXP_RTCTL		28	/* Root Control */
+#define  PCI_EXP_RTCTL_CRSSVE	0x0010	/* CRS Software Visibility Enable */
+#define PCI_EXP_RTCAP		30	/* Root Capabilities */
+#define  PCI_EXP_RTCAP_CRSVIS	0x0001	/* CRS Software Visibility capability */
 #define PCI_EXP_DEVCAP2		36	/* Device Capabilities 2 */
 #define  PCI_EXP_DEVCAP2_ARI	0x00000020 /* ARI Forwarding Supported */
 #define PCI_EXP_DEVCTL2		40	/* Device Control 2 */