summaryrefslogtreecommitdiffstats
path: root/drivers/pci/controller/pci-versatile.c
blob: f59ad2728c0b3266c8308e788d25e9c72f8dd96d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright 2004 Koninklijke Philips Electronics NV
 *
 * Conversion to platform driver and DT:
 * Copyright 2014 Linaro Ltd.
 *
 * 14/04/2005 Initial version, colin.king@philips.com
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/platform_device.h>

#include "../pci.h"

static void __iomem *versatile_pci_base;
static void __iomem *versatile_cfg_base[2];

#define PCI_IMAP(m)		(versatile_pci_base + ((m) * 4))
#define PCI_SMAP(m)		(versatile_pci_base + 0x14 + ((m) * 4))
#define PCI_SELFID		(versatile_pci_base + 0xc)

#define VP_PCI_DEVICE_ID		0x030010ee
#define VP_PCI_CLASS_ID			0x0b400000

static u32 pci_slot_ignore;

static int __init versatile_pci_slot_ignore(char *str)
{
	int retval;
	int slot;

	while ((retval = get_option(&str, &slot))) {
		if ((slot < 0) || (slot > 31))
			pr_err("Illegal slot value: %d\n", slot);
		else
			pci_slot_ignore |= (1 << slot);
	}
	return 1;
}
__setup("pci_slot_ignore=", versatile_pci_slot_ignore);


static void __iomem *versatile_map_bus(struct pci_bus *bus,
				       unsigned int devfn, int offset)
{
	unsigned int busnr = bus->number;

	if (pci_slot_ignore & (1 << PCI_SLOT(devfn)))
		return NULL;

	return versatile_cfg_base[1] + ((busnr << 16) | (devfn << 8) | offset);
}

static struct pci_ops pci_versatile_ops = {
	.map_bus = versatile_map_bus,
	.read	= pci_generic_config_read32,
	.write	= pci_generic_config_write,
};

static int versatile_pci_parse_request_of_pci_ranges(struct device *dev,
						     struct list_head *res)
{
	int err, mem = 1, res_valid = 0;
	resource_size_t iobase;
	struct resource_entry *win, *tmp;

	err = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff, res, &iobase);
	if (err)
		return err;

	err = devm_request_pci_bus_resources(dev, res);
	if (err)
		goto out_release_res;

	resource_list_for_each_entry_safe(win, tmp, res) {
		struct resource *res = win->res;

		switch (resource_type(res)) {
		case IORESOURCE_IO:
			err = devm_pci_remap_iospace(dev, res, iobase);
			if (err) {
				dev_warn(dev, "error %d: failed to map resource %pR\n",
					 err, res);
				resource_list_destroy_entry(win);
			}
			break;
		case IORESOURCE_MEM:
			res_valid |= !(res->flags & IORESOURCE_PREFETCH);

			writel(res->start >> 28, PCI_IMAP(mem));
			writel(PHYS_OFFSET >> 28, PCI_SMAP(mem));
			mem++;

			break;
		}
	}

	if (res_valid)
		return 0;

	dev_err(dev, "non-prefetchable memory resource required\n");
	err = -EINVAL;

out_release_res:
	pci_free_resource_list(res);
	return err;
}

static int versatile_pci_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct resource *res;
	int ret, i, myslot = -1;
	u32 val;
	void __iomem *local_pci_cfg_base;
	struct pci_bus *bus, *child;
	struct pci_host_bridge *bridge;
	LIST_HEAD(pci_res);

	bridge = devm_pci_alloc_host_bridge(dev, 0);
	if (!bridge)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	versatile_pci_base = devm_ioremap_resource(dev, res);
	if (IS_ERR(versatile_pci_base))
		return PTR_ERR(versatile_pci_base);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	versatile_cfg_base[0] = devm_ioremap_resource(dev, res);
	if (IS_ERR(versatile_cfg_base[0]))
		return PTR_ERR(versatile_cfg_base[0]);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
	versatile_cfg_base[1] = devm_pci_remap_cfg_resource(dev, res);
	if (IS_ERR(versatile_cfg_base[1]))
		return PTR_ERR(versatile_cfg_base[1]);

	ret = versatile_pci_parse_request_of_pci_ranges(dev, &pci_res);
	if (ret)
		return ret;

	/*
	 * We need to discover the PCI core first to configure itself
	 * before the main PCI probing is performed
	 */
	for (i = 0; i < 32; i++) {
		if ((readl(versatile_cfg_base[0] + (i << 11) + PCI_VENDOR_ID) == VP_PCI_DEVICE_ID) &&
		    (readl(versatile_cfg_base[0] + (i << 11) + PCI_CLASS_REVISION) == VP_PCI_CLASS_ID)) {
			myslot = i;
			break;
		}
	}
	if (myslot == -1) {
		dev_err(dev, "Cannot find PCI core!\n");
		return -EIO;
	}
	/*
	 * Do not to map Versatile FPGA PCI device into memory space
	 */
	pci_slot_ignore |= (1 << myslot);

	dev_info(dev, "PCI core found (slot %d)\n", myslot);

	writel(myslot, PCI_SELFID);
	local_pci_cfg_base = versatile_cfg_base[1] + (myslot << 11);

	val = readl(local_pci_cfg_base + PCI_COMMAND);
	val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
	writel(val, local_pci_cfg_base + PCI_COMMAND);

	/*
	 * Configure the PCI inbound memory windows to be 1:1 mapped to SDRAM
	 */
	writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_0);
	writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_1);
	writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_2);

	/*
	 * For many years the kernel and QEMU were symbiotically buggy
	 * in that they both assumed the same broken IRQ mapping.
	 * QEMU therefore attempts to auto-detect old broken kernels
	 * so that they still work on newer QEMU as they did on old
	 * QEMU. Since we now use the correct (ie matching-hardware)
	 * IRQ mapping we write a definitely different value to a
	 * PCI_INTERRUPT_LINE register to tell QEMU that we expect
	 * real hardware behaviour and it need not be backwards
	 * compatible for us. This write is harmless on real hardware.
	 */
	writel(0, versatile_cfg_base[0] + PCI_INTERRUPT_LINE);

	pci_add_flags(PCI_ENABLE_PROC_DOMAINS);
	pci_add_flags(PCI_REASSIGN_ALL_BUS);

	list_splice_init(&pci_res, &bridge->windows);
	bridge->dev.parent = dev;
	bridge->sysdata = NULL;
	bridge->busnr = 0;
	bridge->ops = &pci_versatile_ops;
	bridge->map_irq = of_irq_parse_and_map_pci;
	bridge->swizzle_irq = pci_common_swizzle;

	ret = pci_scan_root_bus_bridge(bridge);
	if (ret < 0)
		return ret;

	bus = bridge->bus;

	pci_assign_unassigned_bus_resources(bus);
	list_for_each_entry(child, &bus->children, node)
		pcie_bus_configure_settings(child);
	pci_bus_add_devices(bus);

	return 0;
}

static const struct of_device_id versatile_pci_of_match[] = {
	{ .compatible = "arm,versatile-pci", },
	{ },
};
MODULE_DEVICE_TABLE(of, versatile_pci_of_match);

static struct platform_driver versatile_pci_driver = {
	.driver = {
		.name = "versatile-pci",
		.of_match_table = versatile_pci_of_match,
		.suppress_bind_attrs = true,
	},
	.probe = versatile_pci_probe,
};
module_platform_driver(versatile_pci_driver);

MODULE_DESCRIPTION("Versatile PCI driver");
MODULE_LICENSE("GPL v2");