1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright 2004 Koninklijke Philips Electronics NV
4 *
5 * Conversion to platform driver and DT:
6 * Copyright 2014 Linaro Ltd.
7 *
8 * 14/04/2005 Initial version, colin.king@philips.com
9 */
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/of_address.h>
13 #include <linux/of_pci.h>
14 #include <linux/of_platform.h>
15 #include <linux/pci.h>
16 #include <linux/platform_device.h>
17
18 #include "../pci.h"
19
20 static void __iomem *versatile_pci_base;
21 static void __iomem *versatile_cfg_base[2];
22
23 #define PCI_IMAP(m) (versatile_pci_base + ((m) * 4))
24 #define PCI_SMAP(m) (versatile_pci_base + 0x14 + ((m) * 4))
25 #define PCI_SELFID (versatile_pci_base + 0xc)
26
27 #define VP_PCI_DEVICE_ID 0x030010ee
28 #define VP_PCI_CLASS_ID 0x0b400000
29
30 static u32 pci_slot_ignore;
31
versatile_pci_slot_ignore(char * str)32 static int __init versatile_pci_slot_ignore(char *str)
33 {
34 int slot;
35
36 while (get_option(&str, &slot)) {
37 if ((slot < 0) || (slot > 31))
38 pr_err("Illegal slot value: %d\n", slot);
39 else
40 pci_slot_ignore |= (1 << slot);
41 }
42 return 1;
43 }
44 __setup("pci_slot_ignore=", versatile_pci_slot_ignore);
45
46
versatile_map_bus(struct pci_bus * bus,unsigned int devfn,int offset)47 static void __iomem *versatile_map_bus(struct pci_bus *bus,
48 unsigned int devfn, int offset)
49 {
50 unsigned int busnr = bus->number;
51
52 if (pci_slot_ignore & (1 << PCI_SLOT(devfn)))
53 return NULL;
54
55 return versatile_cfg_base[1] + ((busnr << 16) | (devfn << 8) | offset);
56 }
57
58 static struct pci_ops pci_versatile_ops = {
59 .map_bus = versatile_map_bus,
60 .read = pci_generic_config_read32,
61 .write = pci_generic_config_write,
62 };
63
versatile_pci_probe(struct platform_device * pdev)64 static int versatile_pci_probe(struct platform_device *pdev)
65 {
66 struct device *dev = &pdev->dev;
67 struct resource *res;
68 struct resource_entry *entry;
69 int i, myslot = -1, mem = 1;
70 u32 val;
71 void __iomem *local_pci_cfg_base;
72 struct pci_host_bridge *bridge;
73
74 bridge = devm_pci_alloc_host_bridge(dev, 0);
75 if (!bridge)
76 return -ENOMEM;
77
78 versatile_pci_base = devm_platform_ioremap_resource(pdev, 0);
79 if (IS_ERR(versatile_pci_base))
80 return PTR_ERR(versatile_pci_base);
81
82 versatile_cfg_base[0] = devm_platform_ioremap_resource(pdev, 1);
83 if (IS_ERR(versatile_cfg_base[0]))
84 return PTR_ERR(versatile_cfg_base[0]);
85
86 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
87 versatile_cfg_base[1] = devm_pci_remap_cfg_resource(dev, res);
88 if (IS_ERR(versatile_cfg_base[1]))
89 return PTR_ERR(versatile_cfg_base[1]);
90
91 resource_list_for_each_entry(entry, &bridge->windows) {
92 if (resource_type(entry->res) == IORESOURCE_MEM) {
93 writel(entry->res->start >> 28, PCI_IMAP(mem));
94 writel(__pa(PAGE_OFFSET) >> 28, PCI_SMAP(mem));
95 mem++;
96 }
97 }
98
99 /*
100 * We need to discover the PCI core first to configure itself
101 * before the main PCI probing is performed
102 */
103 for (i = 0; i < 32; i++) {
104 if ((readl(versatile_cfg_base[0] + (i << 11) + PCI_VENDOR_ID) == VP_PCI_DEVICE_ID) &&
105 (readl(versatile_cfg_base[0] + (i << 11) + PCI_CLASS_REVISION) == VP_PCI_CLASS_ID)) {
106 myslot = i;
107 break;
108 }
109 }
110 if (myslot == -1) {
111 dev_err(dev, "Cannot find PCI core!\n");
112 return -EIO;
113 }
114 /*
115 * Do not to map Versatile FPGA PCI device into memory space
116 */
117 pci_slot_ignore |= (1 << myslot);
118
119 dev_info(dev, "PCI core found (slot %d)\n", myslot);
120
121 writel(myslot, PCI_SELFID);
122 local_pci_cfg_base = versatile_cfg_base[1] + (myslot << 11);
123
124 val = readl(local_pci_cfg_base + PCI_COMMAND);
125 val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
126 writel(val, local_pci_cfg_base + PCI_COMMAND);
127
128 /*
129 * Configure the PCI inbound memory windows to be 1:1 mapped to SDRAM
130 */
131 writel(__pa(PAGE_OFFSET), local_pci_cfg_base + PCI_BASE_ADDRESS_0);
132 writel(__pa(PAGE_OFFSET), local_pci_cfg_base + PCI_BASE_ADDRESS_1);
133 writel(__pa(PAGE_OFFSET), local_pci_cfg_base + PCI_BASE_ADDRESS_2);
134
135 /*
136 * For many years the kernel and QEMU were symbiotically buggy
137 * in that they both assumed the same broken IRQ mapping.
138 * QEMU therefore attempts to auto-detect old broken kernels
139 * so that they still work on newer QEMU as they did on old
140 * QEMU. Since we now use the correct (ie matching-hardware)
141 * IRQ mapping we write a definitely different value to a
142 * PCI_INTERRUPT_LINE register to tell QEMU that we expect
143 * real hardware behaviour and it need not be backwards
144 * compatible for us. This write is harmless on real hardware.
145 */
146 writel(0, versatile_cfg_base[0] + PCI_INTERRUPT_LINE);
147
148 pci_add_flags(PCI_REASSIGN_ALL_BUS);
149
150 bridge->ops = &pci_versatile_ops;
151
152 return pci_host_probe(bridge);
153 }
154
155 static const struct of_device_id versatile_pci_of_match[] = {
156 { .compatible = "arm,versatile-pci", },
157 { },
158 };
159 MODULE_DEVICE_TABLE(of, versatile_pci_of_match);
160
161 static struct platform_driver versatile_pci_driver = {
162 .driver = {
163 .name = "versatile-pci",
164 .of_match_table = versatile_pci_of_match,
165 .suppress_bind_attrs = true,
166 },
167 .probe = versatile_pci_probe,
168 };
169 module_platform_driver(versatile_pci_driver);
170
171 MODULE_DESCRIPTION("Versatile PCI driver");
172