tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright 2004 Koninklijke Philips Electronics NV
3 *
4 * Conversion to platform driver and DT:
5 * Copyright 2014 Linaro Ltd.
6 *
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * 14/04/2005 Initial version, colin.king@philips.com
17 */
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/of_address.h>
21#include <linux/of_pci.h>
22#include <linux/of_platform.h>
23#include <linux/pci.h>
24#include <linux/platform_device.h>
25
26static void __iomem *versatile_pci_base;
27static void __iomem *versatile_cfg_base[2];
28
29#define PCI_IMAP(m) (versatile_pci_base + ((m) * 4))
30#define PCI_SMAP(m) (versatile_pci_base + 0x14 + ((m) * 4))
31#define PCI_SELFID (versatile_pci_base + 0xc)
32
33#define VP_PCI_DEVICE_ID 0x030010ee
34#define VP_PCI_CLASS_ID 0x0b400000
35
36static u32 pci_slot_ignore;
37
38static int __init versatile_pci_slot_ignore(char *str)
39{
40 int retval;
41 int slot;
42
43 while ((retval = get_option(&str, &slot))) {
44 if ((slot < 0) || (slot > 31))
45 pr_err("Illegal slot value: %d\n", slot);
46 else
47 pci_slot_ignore |= (1 << slot);
48 }
49 return 1;
50}
51__setup("pci_slot_ignore=", versatile_pci_slot_ignore);
52
53
54static void __iomem *versatile_map_bus(struct pci_bus *bus,
55 unsigned int devfn, int offset)
56{
57 unsigned int busnr = bus->number;
58
59 if (pci_slot_ignore & (1 << PCI_SLOT(devfn)))
60 return NULL;
61
62 return versatile_cfg_base[1] + ((busnr << 16) | (devfn << 8) | offset);
63}
64
65static struct pci_ops pci_versatile_ops = {
66 .map_bus = versatile_map_bus,
67 .read = pci_generic_config_read32,
68 .write = pci_generic_config_write,
69};
70
71static int versatile_pci_parse_request_of_pci_ranges(struct device *dev,
72 struct list_head *res)
73{
74 int err, mem = 1, res_valid = 0;
75 struct device_node *np = dev->of_node;
76 resource_size_t iobase;
77 struct resource_entry *win;
78
79 err = of_pci_get_host_bridge_resources(np, 0, 0xff, res, &iobase);
80 if (err)
81 return err;
82
83 err = devm_request_pci_bus_resources(dev, res);
84 if (err)
85 goto out_release_res;
86
87 resource_list_for_each_entry(win, res) {
88 struct resource *res = win->res;
89
90 switch (resource_type(res)) {
91 case IORESOURCE_IO:
92 err = pci_remap_iospace(res, iobase);
93 if (err)
94 dev_warn(dev, "error %d: failed to map resource %pR\n",
95 err, res);
96 break;
97 case IORESOURCE_MEM:
98 res_valid |= !(res->flags & IORESOURCE_PREFETCH);
99
100 writel(res->start >> 28, PCI_IMAP(mem));
101 writel(PHYS_OFFSET >> 28, PCI_SMAP(mem));
102 mem++;
103
104 break;
105 }
106 }
107
108 if (res_valid)
109 return 0;
110
111 dev_err(dev, "non-prefetchable memory resource required\n");
112 err = -EINVAL;
113
114out_release_res:
115 pci_free_resource_list(res);
116 return err;
117}
118
119static int versatile_pci_probe(struct platform_device *pdev)
120{
121 struct resource *res;
122 int ret, i, myslot = -1;
123 u32 val;
124 void __iomem *local_pci_cfg_base;
125 struct pci_bus *bus;
126 LIST_HEAD(pci_res);
127
128 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
129 versatile_pci_base = devm_ioremap_resource(&pdev->dev, res);
130 if (IS_ERR(versatile_pci_base))
131 return PTR_ERR(versatile_pci_base);
132
133 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
134 versatile_cfg_base[0] = devm_ioremap_resource(&pdev->dev, res);
135 if (IS_ERR(versatile_cfg_base[0]))
136 return PTR_ERR(versatile_cfg_base[0]);
137
138 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
139 versatile_cfg_base[1] = devm_ioremap_resource(&pdev->dev, res);
140 if (IS_ERR(versatile_cfg_base[1]))
141 return PTR_ERR(versatile_cfg_base[1]);
142
143 ret = versatile_pci_parse_request_of_pci_ranges(&pdev->dev, &pci_res);
144 if (ret)
145 return ret;
146
147 /*
148 * We need to discover the PCI core first to configure itself
149 * before the main PCI probing is performed
150 */
151 for (i = 0; i < 32; i++) {
152 if ((readl(versatile_cfg_base[0] + (i << 11) + PCI_VENDOR_ID) == VP_PCI_DEVICE_ID) &&
153 (readl(versatile_cfg_base[0] + (i << 11) + PCI_CLASS_REVISION) == VP_PCI_CLASS_ID)) {
154 myslot = i;
155 break;
156 }
157 }
158 if (myslot == -1) {
159 dev_err(&pdev->dev, "Cannot find PCI core!\n");
160 return -EIO;
161 }
162 /*
163 * Do not to map Versatile FPGA PCI device into memory space
164 */
165 pci_slot_ignore |= (1 << myslot);
166
167 dev_info(&pdev->dev, "PCI core found (slot %d)\n", myslot);
168
169 writel(myslot, PCI_SELFID);
170 local_pci_cfg_base = versatile_cfg_base[1] + (myslot << 11);
171
172 val = readl(local_pci_cfg_base + PCI_COMMAND);
173 val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
174 writel(val, local_pci_cfg_base + PCI_COMMAND);
175
176 /*
177 * Configure the PCI inbound memory windows to be 1:1 mapped to SDRAM
178 */
179 writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_0);
180 writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_1);
181 writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_2);
182
183 /*
184 * For many years the kernel and QEMU were symbiotically buggy
185 * in that they both assumed the same broken IRQ mapping.
186 * QEMU therefore attempts to auto-detect old broken kernels
187 * so that they still work on newer QEMU as they did on old
188 * QEMU. Since we now use the correct (ie matching-hardware)
189 * IRQ mapping we write a definitely different value to a
190 * PCI_INTERRUPT_LINE register to tell QEMU that we expect
191 * real hardware behaviour and it need not be backwards
192 * compatible for us. This write is harmless on real hardware.
193 */
194 writel(0, versatile_cfg_base[0] + PCI_INTERRUPT_LINE);
195
196 pci_add_flags(PCI_ENABLE_PROC_DOMAINS);
197 pci_add_flags(PCI_REASSIGN_ALL_BUS | PCI_REASSIGN_ALL_RSRC);
198
199 bus = pci_scan_root_bus(&pdev->dev, 0, &pci_versatile_ops, NULL, &pci_res);
200 if (!bus)
201 return -ENOMEM;
202
203 pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
204 pci_assign_unassigned_bus_resources(bus);
205 pci_bus_add_devices(bus);
206
207 return 0;
208}
209
210static const struct of_device_id versatile_pci_of_match[] = {
211 { .compatible = "arm,versatile-pci", },
212 { },
213};
214MODULE_DEVICE_TABLE(of, versatile_pci_of_match);
215
216static struct platform_driver versatile_pci_driver = {
217 .driver = {
218 .name = "versatile-pci",
219 .of_match_table = versatile_pci_of_match,
220 },
221 .probe = versatile_pci_probe,
222};
223module_platform_driver(versatile_pci_driver);
224
225MODULE_DESCRIPTION("Versatile PCI driver");
226MODULE_LICENSE("GPL v2");