PCI: switchtec: Add Microchip PCI100X device IDs

Add Microchip parts to the Device ID table so the driver supports PCI100x
devices.

Add a new macro to quirk the Microchip Switchtec PCI100x parts to allow DMA
access via NTB to work when the IOMMU is turned on.

PCI100x family has 6 variants; each variant is designed for different
application usages, different port counts and lane counts:

  PCI1001 has 1 x4 upstream port and 3 x4 downstream ports
  PCI1002 has 1 x4 upstream port and 4 x2 downstream ports
  PCI1003 has 2 x4 upstream ports, 2 x2 upstream ports, and 2 x2
    downstream ports
  PCI1004 has 4 x4 upstream ports
  PCI1005 has 1 x4 upstream port and 6 x2 downstream ports
  PCI1006 has 6 x2 upstream ports and 2 x2 downstream ports

[Historical note: these parts use PCI_VENDOR_ID_EFAR (0x1055), from EFAR
Microsystems, which was acquired in 1996 by Standard Microsystems Corp,
which was acquired by Microchip Technology in 2012.  The PCI-SIG confirms
that Vendor ID 0x1055 is assigned to Microchip even though it's not
visible via https://pcisig.com/membership/member-companies]

Link: https://lore.kernel.org/r/20250120095524.243103-1-Saladi.Rakeshbabu@microchip.com
Signed-off-by: Rakesh Babu Saladi <Saladi.Rakeshbabu@microchip.com>
[bhelgaas: Vendor ID history]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-By: Logan Gunthorpe <logang@deltatee.com>

Author: Rakesh-Saladi

drivers/pci/quirks.c

@@ -5984,6 +5984,17 @@ SWITCHTEC_QUIRK(0x5552);  /* PAXA 52XG5 */
 SWITCHTEC_QUIRK(0x5536);  /* PAXA 36XG5 */
 SWITCHTEC_QUIRK(0x5528);  /* PAXA 28XG5 */
 
+#define SWITCHTEC_PCI100X_QUIRK(vid) \
+	DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_EFAR, vid, \
+		PCI_CLASS_BRIDGE_OTHER, 8, quirk_switchtec_ntb_dma_alias)
+SWITCHTEC_PCI100X_QUIRK(0x1001);  /* PCI1001XG4 */
+SWITCHTEC_PCI100X_QUIRK(0x1002);  /* PCI1002XG4 */
+SWITCHTEC_PCI100X_QUIRK(0x1003);  /* PCI1003XG4 */
+SWITCHTEC_PCI100X_QUIRK(0x1004);  /* PCI1004XG4 */
+SWITCHTEC_PCI100X_QUIRK(0x1005);  /* PCI1005XG4 */
+SWITCHTEC_PCI100X_QUIRK(0x1006);  /* PCI1006XG4 */
+
+
 /*
  * The PLX NTB uses devfn proxy IDs to move TLPs between NT endpoints.
  * These IDs are used to forward responses to the originator on the other

drivers/pci/switch/switchtec.c

@@ -1739,6 +1739,26 @@ static void switchtec_pci_remove(struct pci_dev *pdev)
 		.driver_data = gen, \
 	}
 
+#define SWITCHTEC_PCI100X_DEVICE(device_id, gen) \
+	{ \
+		.vendor     = PCI_VENDOR_ID_EFAR, \
+		.device     = device_id, \
+		.subvendor  = PCI_ANY_ID, \
+		.subdevice  = PCI_ANY_ID, \
+		.class      = (PCI_CLASS_MEMORY_OTHER << 8), \
+		.class_mask = 0xFFFFFFFF, \
+		.driver_data = gen, \
+	}, \
+	{ \
+		.vendor     = PCI_VENDOR_ID_EFAR, \
+		.device     = device_id, \
+		.subvendor  = PCI_ANY_ID, \
+		.subdevice  = PCI_ANY_ID, \
+		.class      = (PCI_CLASS_BRIDGE_OTHER << 8), \
+		.class_mask = 0xFFFFFFFF, \
+		.driver_data = gen, \
+	}
+
 static const struct pci_device_id switchtec_pci_tbl[] = {
 	SWITCHTEC_PCI_DEVICE(0x8531, SWITCHTEC_GEN3),  /* PFX 24xG3 */
 	SWITCHTEC_PCI_DEVICE(0x8532, SWITCHTEC_GEN3),  /* PFX 32xG3 */
@@ -1833,6 +1853,12 @@ static const struct pci_device_id switchtec_pci_tbl[] = {
 	SWITCHTEC_PCI_DEVICE(0x5552, SWITCHTEC_GEN5),  /* PAXA 52XG5 */
 	SWITCHTEC_PCI_DEVICE(0x5536, SWITCHTEC_GEN5),  /* PAXA 36XG5 */
 	SWITCHTEC_PCI_DEVICE(0x5528, SWITCHTEC_GEN5),  /* PAXA 28XG5 */
+	SWITCHTEC_PCI100X_DEVICE(0x1001, SWITCHTEC_GEN4),  /* PCI1001 16XG4 */
+	SWITCHTEC_PCI100X_DEVICE(0x1002, SWITCHTEC_GEN4),  /* PCI1002 12XG4 */
+	SWITCHTEC_PCI100X_DEVICE(0x1003, SWITCHTEC_GEN4),  /* PCI1003 16XG4 */
+	SWITCHTEC_PCI100X_DEVICE(0x1004, SWITCHTEC_GEN4),  /* PCI1004 16XG4 */
+	SWITCHTEC_PCI100X_DEVICE(0x1005, SWITCHTEC_GEN4),  /* PCI1005 16XG4 */
+	SWITCHTEC_PCI100X_DEVICE(0x1006, SWITCHTEC_GEN4),  /* PCI1006 16XG4 */
 	{0}
 };
 MODULE_DEVICE_TABLE(pci, switchtec_pci_tbl);