1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/drivers/misc/xillybus_pcie.c
4  *
5  * Copyright 2011 Xillybus Ltd, http://xillybus.com
6  *
7  * Driver for the Xillybus FPGA/host framework using PCI Express.
8  */
9 
10 #include <linux/module.h>
11 #include <linux/pci.h>
12 #include <linux/slab.h>
13 #include "xillybus.h"
14 
15 MODULE_DESCRIPTION("Xillybus driver for PCIe");
16 MODULE_AUTHOR("Eli Billauer, Xillybus Ltd.");
17 MODULE_ALIAS("xillybus_pcie");
18 MODULE_LICENSE("GPL v2");
19 
20 #define PCI_DEVICE_ID_XILLYBUS		0xebeb
21 
22 #define PCI_VENDOR_ID_ACTEL		0x11aa
23 #define PCI_VENDOR_ID_LATTICE		0x1204
24 
25 static const char xillyname[] = "xillybus_pcie";
26 
27 static const struct pci_device_id xillyids[] = {
28 	{PCI_DEVICE(PCI_VENDOR_ID_XILINX, PCI_DEVICE_ID_XILLYBUS)},
29 	{PCI_DEVICE(PCI_VENDOR_ID_ALTERA, PCI_DEVICE_ID_XILLYBUS)},
30 	{PCI_DEVICE(PCI_VENDOR_ID_ACTEL, PCI_DEVICE_ID_XILLYBUS)},
31 	{PCI_DEVICE(PCI_VENDOR_ID_LATTICE, PCI_DEVICE_ID_XILLYBUS)},
32 	{ /* End: all zeroes */ }
33 };
34 
35 static int xilly_probe(struct pci_dev *pdev,
36 		       const struct pci_device_id *ent)
37 {
38 	struct xilly_endpoint *endpoint;
39 	int rc;
40 
41 	endpoint = xillybus_init_endpoint(&pdev->dev);
42 
43 	if (!endpoint)
44 		return -ENOMEM;
45 
46 	pci_set_drvdata(pdev, endpoint);
47 
48 	endpoint->owner = THIS_MODULE;
49 
50 	rc = pcim_enable_device(pdev);
51 	if (rc) {
52 		dev_err(endpoint->dev,
53 			"pcim_enable_device() failed. Aborting.\n");
54 		return rc;
55 	}
56 
57 	/* L0s has caused packet drops. No power saving, thank you. */
58 
59 	pci_disable_link_state(pdev, PCIE_LINK_STATE_L0S);
60 
61 	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
62 		dev_err(endpoint->dev,
63 			"Incorrect BAR configuration. Aborting.\n");
64 		return -ENODEV;
65 	}
66 
67 	rc = pcim_iomap_regions(pdev, 0x01, xillyname);
68 	if (rc) {
69 		dev_err(endpoint->dev,
70 			"pcim_iomap_regions() failed. Aborting.\n");
71 		return rc;
72 	}
73 
74 	endpoint->registers = pcim_iomap_table(pdev)[0];
75 
76 	pci_set_master(pdev);
77 
78 	/* Set up a single MSI interrupt */
79 	if (pci_enable_msi(pdev)) {
80 		dev_err(endpoint->dev,
81 			"Failed to enable MSI interrupts. Aborting.\n");
82 		return -ENODEV;
83 	}
84 	rc = devm_request_irq(&pdev->dev, pdev->irq, xillybus_isr, 0,
85 			      xillyname, endpoint);
86 	if (rc) {
87 		dev_err(endpoint->dev,
88 			"Failed to register MSI handler. Aborting.\n");
89 		return -ENODEV;
90 	}
91 
92 	/*
93 	 * Some (old and buggy?) hardware drops 64-bit addressed PCIe packets,
94 	 * even when the PCIe driver claims that a 64-bit mask is OK. On the
95 	 * other hand, on some architectures, 64-bit addressing is mandatory.
96 	 * So go for the 64-bit mask only when failing is the other option.
97 	 */
98 
99 	if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(32))) {
100 		endpoint->dma_using_dac = 0;
101 	} else if (!dma_set_mask(&pdev->dev, DMA_BIT_MASK(64))) {
102 		endpoint->dma_using_dac = 1;
103 	} else {
104 		dev_err(endpoint->dev, "Failed to set DMA mask. Aborting.\n");
105 		return -ENODEV;
106 	}
107 
108 	return xillybus_endpoint_discovery(endpoint);
109 }
110 
111 static void xilly_remove(struct pci_dev *pdev)
112 {
113 	struct xilly_endpoint *endpoint = pci_get_drvdata(pdev);
114 
115 	xillybus_endpoint_remove(endpoint);
116 }
117 
118 MODULE_DEVICE_TABLE(pci, xillyids);
119 
120 static struct pci_driver xillybus_driver = {
121 	.name = xillyname,
122 	.id_table = xillyids,
123 	.probe = xilly_probe,
124 	.remove = xilly_remove,
125 };
126 
127 module_pci_driver(xillybus_driver);
128