xref: /openbmc/linux/drivers/mcb/mcb-pci.c (revision 2a954832)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * MEN Chameleon Bus.
4  *
5  * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
6  * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/mcb.h>
12 
13 #include "mcb-internal.h"
14 
15 struct priv {
16 	struct mcb_bus *bus;
17 	phys_addr_t mapbase;
18 	void __iomem *base;
19 };
20 
21 static int mcb_pci_get_irq(struct mcb_device *mdev)
22 {
23 	struct mcb_bus *mbus = mdev->bus;
24 	struct device *dev = mbus->carrier;
25 	struct pci_dev *pdev = to_pci_dev(dev);
26 
27 	return pdev->irq;
28 }
29 
30 static int mcb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
31 {
32 	struct resource *res;
33 	struct priv *priv;
34 	int ret, table_size;
35 	unsigned long flags;
36 
37 	priv = devm_kzalloc(&pdev->dev, sizeof(struct priv), GFP_KERNEL);
38 	if (!priv)
39 		return -ENOMEM;
40 
41 	ret = pci_enable_device(pdev);
42 	if (ret) {
43 		dev_err(&pdev->dev, "Failed to enable PCI device\n");
44 		return -ENODEV;
45 	}
46 	pci_set_master(pdev);
47 
48 	priv->mapbase = pci_resource_start(pdev, 0);
49 	if (!priv->mapbase) {
50 		dev_err(&pdev->dev, "No PCI resource\n");
51 		ret = -ENODEV;
52 		goto out_disable;
53 	}
54 
55 	res = devm_request_mem_region(&pdev->dev, priv->mapbase,
56 				      CHAM_HEADER_SIZE,
57 				      KBUILD_MODNAME);
58 	if (!res) {
59 		dev_err(&pdev->dev, "Failed to request PCI memory\n");
60 		ret = -EBUSY;
61 		goto out_disable;
62 	}
63 
64 	priv->base = devm_ioremap(&pdev->dev, priv->mapbase, CHAM_HEADER_SIZE);
65 	if (!priv->base) {
66 		dev_err(&pdev->dev, "Cannot ioremap\n");
67 		ret = -ENOMEM;
68 		goto out_disable;
69 	}
70 
71 	flags = pci_resource_flags(pdev, 0);
72 	if (flags & IORESOURCE_IO) {
73 		ret = -ENOTSUPP;
74 		dev_err(&pdev->dev,
75 			"IO mapped PCI devices are not supported\n");
76 		goto out_disable;
77 	}
78 
79 	pci_set_drvdata(pdev, priv);
80 
81 	priv->bus = mcb_alloc_bus(&pdev->dev);
82 	if (IS_ERR(priv->bus)) {
83 		ret = PTR_ERR(priv->bus);
84 		goto out_disable;
85 	}
86 
87 	priv->bus->get_irq = mcb_pci_get_irq;
88 
89 	ret = chameleon_parse_cells(priv->bus, priv->mapbase, priv->base);
90 	if (ret < 0)
91 		goto out_mcb_bus;
92 
93 	table_size = ret;
94 
95 	if (table_size < CHAM_HEADER_SIZE) {
96 		/* Release the previous resources */
97 		devm_iounmap(&pdev->dev, priv->base);
98 		devm_release_mem_region(&pdev->dev, priv->mapbase, CHAM_HEADER_SIZE);
99 
100 		/* Then, allocate it again with the actual chameleon table size */
101 		res = devm_request_mem_region(&pdev->dev, priv->mapbase,
102 						table_size,
103 						KBUILD_MODNAME);
104 		if (!res) {
105 			dev_err(&pdev->dev, "Failed to request PCI memory\n");
106 			ret = -EBUSY;
107 			goto out_mcb_bus;
108 		}
109 
110 		priv->base = devm_ioremap(&pdev->dev, priv->mapbase, table_size);
111 		if (!priv->base) {
112 			dev_err(&pdev->dev, "Cannot ioremap\n");
113 			ret = -ENOMEM;
114 			goto out_mcb_bus;
115 		}
116 	}
117 
118 	mcb_bus_add_devices(priv->bus);
119 
120 	return 0;
121 
122 out_mcb_bus:
123 	mcb_release_bus(priv->bus);
124 out_disable:
125 	pci_disable_device(pdev);
126 	return ret;
127 }
128 
129 static void mcb_pci_remove(struct pci_dev *pdev)
130 {
131 	struct priv *priv = pci_get_drvdata(pdev);
132 
133 	mcb_release_bus(priv->bus);
134 
135 	pci_disable_device(pdev);
136 }
137 
138 static const struct pci_device_id mcb_pci_tbl[] = {
139 	{ PCI_DEVICE(PCI_VENDOR_ID_MEN, PCI_DEVICE_ID_MEN_CHAMELEON) },
140 	{ PCI_DEVICE(PCI_VENDOR_ID_ALTERA, PCI_DEVICE_ID_MEN_CHAMELEON) },
141 	{ 0 },
142 };
143 MODULE_DEVICE_TABLE(pci, mcb_pci_tbl);
144 
145 static struct pci_driver mcb_pci_driver = {
146 	.name = "mcb-pci",
147 	.id_table = mcb_pci_tbl,
148 	.probe = mcb_pci_probe,
149 	.remove = mcb_pci_remove,
150 };
151 
152 module_pci_driver(mcb_pci_driver);
153 
154 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
155 MODULE_LICENSE("GPL");
156 MODULE_DESCRIPTION("MCB over PCI support");
157 MODULE_IMPORT_NS(MCB);
158