1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCIe host controller driver for HiSilicon SoCs
4  *
5  * Copyright (C) 2015 HiSilicon Co., Ltd. http://www.hisilicon.com
6  *
7  * Authors: Zhou Wang <wangzhou1@hisilicon.com>
8  *          Dacai Zhu <zhudacai@hisilicon.com>
9  *          Gabriele Paoloni <gabriele.paoloni@huawei.com>
10  */
11 #include <linux/interrupt.h>
12 #include <linux/init.h>
13 #include <linux/platform_device.h>
14 #include <linux/pci.h>
15 #include <linux/pci-acpi.h>
16 #include <linux/pci-ecam.h>
17 #include "../../pci.h"
18 
19 #if defined(CONFIG_PCI_HISI) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
20 
21 struct hisi_pcie {
22 	void __iomem	*reg_base;
23 };
24 
25 static int hisi_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
26 			     int size, u32 *val)
27 {
28 	struct pci_config_window *cfg = bus->sysdata;
29 	int dev = PCI_SLOT(devfn);
30 
31 	if (bus->number == cfg->busr.start) {
32 		/* access only one slot on each root port */
33 		if (dev > 0)
34 			return PCIBIOS_DEVICE_NOT_FOUND;
35 		else
36 			return pci_generic_config_read32(bus, devfn, where,
37 							 size, val);
38 	}
39 
40 	return pci_generic_config_read(bus, devfn, where, size, val);
41 }
42 
43 static int hisi_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
44 			     int where, int size, u32 val)
45 {
46 	struct pci_config_window *cfg = bus->sysdata;
47 	int dev = PCI_SLOT(devfn);
48 
49 	if (bus->number == cfg->busr.start) {
50 		/* access only one slot on each root port */
51 		if (dev > 0)
52 			return PCIBIOS_DEVICE_NOT_FOUND;
53 		else
54 			return pci_generic_config_write32(bus, devfn, where,
55 							  size, val);
56 	}
57 
58 	return pci_generic_config_write(bus, devfn, where, size, val);
59 }
60 
61 static void __iomem *hisi_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
62 				       int where)
63 {
64 	struct pci_config_window *cfg = bus->sysdata;
65 	struct hisi_pcie *pcie = cfg->priv;
66 
67 	if (bus->number == cfg->busr.start)
68 		return pcie->reg_base + where;
69 	else
70 		return pci_ecam_map_bus(bus, devfn, where);
71 }
72 
73 #if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
74 
75 static int hisi_pcie_init(struct pci_config_window *cfg)
76 {
77 	struct device *dev = cfg->parent;
78 	struct hisi_pcie *pcie;
79 	struct acpi_device *adev = to_acpi_device(dev);
80 	struct acpi_pci_root *root = acpi_driver_data(adev);
81 	struct resource *res;
82 	int ret;
83 
84 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
85 	if (!pcie)
86 		return -ENOMEM;
87 
88 	/*
89 	 * Retrieve RC base and size from a HISI0081 device with _UID
90 	 * matching our segment.
91 	 */
92 	res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
93 	if (!res)
94 		return -ENOMEM;
95 
96 	ret = acpi_get_rc_resources(dev, "HISI0081", root->segment, res);
97 	if (ret) {
98 		dev_err(dev, "can't get rc base address\n");
99 		return -ENOMEM;
100 	}
101 
102 	pcie->reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
103 	if (!pcie->reg_base)
104 		return -ENOMEM;
105 
106 	cfg->priv = pcie;
107 	return 0;
108 }
109 
110 const struct pci_ecam_ops hisi_pcie_ops = {
111 	.init         =  hisi_pcie_init,
112 	.pci_ops      = {
113 		.map_bus    = hisi_pcie_map_bus,
114 		.read       = hisi_pcie_rd_conf,
115 		.write      = hisi_pcie_wr_conf,
116 	}
117 };
118 
119 #endif
120 
121 #ifdef CONFIG_PCI_HISI
122 
123 static int hisi_pcie_platform_init(struct pci_config_window *cfg)
124 {
125 	struct device *dev = cfg->parent;
126 	struct hisi_pcie *pcie;
127 	struct platform_device *pdev = to_platform_device(dev);
128 	struct resource *res;
129 
130 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
131 	if (!pcie)
132 		return -ENOMEM;
133 
134 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
135 	if (!res) {
136 		dev_err(dev, "missing \"reg[1]\"property\n");
137 		return -EINVAL;
138 	}
139 
140 	pcie->reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
141 	if (!pcie->reg_base)
142 		return -ENOMEM;
143 
144 	cfg->priv = pcie;
145 	return 0;
146 }
147 
148 static const struct pci_ecam_ops hisi_pcie_platform_ops = {
149 	.init         =  hisi_pcie_platform_init,
150 	.pci_ops      = {
151 		.map_bus    = hisi_pcie_map_bus,
152 		.read       = hisi_pcie_rd_conf,
153 		.write      = hisi_pcie_wr_conf,
154 	}
155 };
156 
157 static const struct of_device_id hisi_pcie_almost_ecam_of_match[] = {
158 	{
159 		.compatible =  "hisilicon,hip06-pcie-ecam",
160 		.data	    =  &hisi_pcie_platform_ops,
161 	},
162 	{
163 		.compatible =  "hisilicon,hip07-pcie-ecam",
164 		.data       =  &hisi_pcie_platform_ops,
165 	},
166 	{},
167 };
168 
169 static struct platform_driver hisi_pcie_almost_ecam_driver = {
170 	.probe  = pci_host_common_probe,
171 	.driver = {
172 		   .name = "hisi-pcie-almost-ecam",
173 		   .of_match_table = hisi_pcie_almost_ecam_of_match,
174 		   .suppress_bind_attrs = true,
175 	},
176 };
177 builtin_platform_driver(hisi_pcie_almost_ecam_driver);
178 
179 #endif
180 #endif
181