xref: /openbmc/u-boot/drivers/pci/pci_sandbox.c (revision bf494d7e)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2014 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <fdtdec.h>
10 #include <pci.h>
11 
12 #define FDT_DEV_INFO_CELLS	4
13 #define FDT_DEV_INFO_SIZE	(FDT_DEV_INFO_CELLS * sizeof(u32))
14 
15 #define SANDBOX_PCI_DEVFN(d, f)	((d << 3) | f)
16 
17 struct sandbox_pci_priv {
18 	struct {
19 		u16 vendor;
20 		u16 device;
21 	} vendev[256];
22 };
23 
24 static int sandbox_pci_write_config(struct udevice *bus, pci_dev_t devfn,
25 				    uint offset, ulong value,
26 				    enum pci_size_t size)
27 {
28 	struct dm_pci_emul_ops *ops;
29 	struct udevice *container, *emul;
30 	int ret;
31 
32 	ret = sandbox_pci_get_emul(bus, devfn, &container, &emul);
33 	if (ret)
34 		return ret == -ENODEV ? 0 : ret;
35 	ops = pci_get_emul_ops(emul);
36 	if (!ops || !ops->write_config)
37 		return -ENOSYS;
38 
39 	return ops->write_config(emul, offset, value, size);
40 }
41 
42 static int sandbox_pci_read_config(struct udevice *bus, pci_dev_t devfn,
43 				   uint offset, ulong *valuep,
44 				   enum pci_size_t size)
45 {
46 	struct dm_pci_emul_ops *ops;
47 	struct udevice *container, *emul;
48 	struct sandbox_pci_priv *priv = dev_get_priv(bus);
49 	int ret;
50 
51 	/* Prepare the default response */
52 	*valuep = pci_get_ff(size);
53 	ret = sandbox_pci_get_emul(bus, devfn, &container, &emul);
54 	if (ret) {
55 		if (!container) {
56 			u16 vendor, device;
57 
58 			devfn = SANDBOX_PCI_DEVFN(PCI_DEV(devfn),
59 						  PCI_FUNC(devfn));
60 			vendor = priv->vendev[devfn].vendor;
61 			device = priv->vendev[devfn].device;
62 			if (offset == PCI_VENDOR_ID && vendor)
63 				*valuep = vendor;
64 			else if (offset == PCI_DEVICE_ID && device)
65 				*valuep = device;
66 
67 			return 0;
68 		} else {
69 			return ret == -ENODEV ? 0 : ret;
70 		}
71 	}
72 	ops = pci_get_emul_ops(emul);
73 	if (!ops || !ops->read_config)
74 		return -ENOSYS;
75 
76 	return ops->read_config(emul, offset, valuep, size);
77 }
78 
79 static int sandbox_pci_probe(struct udevice *dev)
80 {
81 	struct sandbox_pci_priv *priv = dev_get_priv(dev);
82 	const fdt32_t *cell;
83 	u8 pdev, pfn, devfn;
84 	int len;
85 
86 	cell = ofnode_get_property(dev_ofnode(dev), "sandbox,dev-info", &len);
87 	if (!cell)
88 		return 0;
89 
90 	if ((len % FDT_DEV_INFO_SIZE) == 0) {
91 		int num = len / FDT_DEV_INFO_SIZE;
92 		int i;
93 
94 		for (i = 0; i < num; i++) {
95 			debug("dev info #%d: %02x %02x %04x %04x\n", i,
96 			      fdt32_to_cpu(cell[0]), fdt32_to_cpu(cell[1]),
97 			      fdt32_to_cpu(cell[2]), fdt32_to_cpu(cell[3]));
98 
99 			pdev = fdt32_to_cpu(cell[0]);
100 			pfn = fdt32_to_cpu(cell[1]);
101 			if (pdev > 31 || pfn > 7)
102 				continue;
103 			devfn = SANDBOX_PCI_DEVFN(pdev, pfn);
104 			priv->vendev[devfn].vendor = fdt32_to_cpu(cell[2]);
105 			priv->vendev[devfn].device = fdt32_to_cpu(cell[3]);
106 
107 			cell += FDT_DEV_INFO_CELLS;
108 		}
109 	}
110 
111 	return 0;
112 }
113 
114 static const struct dm_pci_ops sandbox_pci_ops = {
115 	.read_config = sandbox_pci_read_config,
116 	.write_config = sandbox_pci_write_config,
117 };
118 
119 static const struct udevice_id sandbox_pci_ids[] = {
120 	{ .compatible = "sandbox,pci" },
121 	{ }
122 };
123 
124 U_BOOT_DRIVER(pci_sandbox) = {
125 	.name	= "pci_sandbox",
126 	.id	= UCLASS_PCI,
127 	.of_match = sandbox_pci_ids,
128 	.ops	= &sandbox_pci_ops,
129 	.probe	= sandbox_pci_probe,
130 	.priv_auto_alloc_size = sizeof(struct sandbox_pci_priv),
131 
132 	/* Attach an emulator if we can */
133 	.child_post_bind = dm_scan_fdt_dev,
134 	.per_child_platdata_auto_alloc_size =
135 			sizeof(struct pci_child_platdata),
136 };
137