1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Cadence PCIe platform  driver.
4  *
5  * Copyright (c) 2019, Cadence Design Systems
6  * Author: Tom Joseph <tjoseph@cadence.com>
7  */
8 #include <linux/kernel.h>
9 #include <linux/of_address.h>
10 #include <linux/of_pci.h>
11 #include <linux/platform_device.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/of_device.h>
14 #include "pcie-cadence.h"
15 
16 #define CDNS_PLAT_CPU_TO_BUS_ADDR	0x0FFFFFFF
17 
18 /**
19  * struct cdns_plat_pcie - private data for this PCIe platform driver
20  * @pcie: Cadence PCIe controller
21  * @is_rc: Set to 1 indicates the PCIe controller mode is Root Complex,
22  *         if 0 it is in Endpoint mode.
23  */
24 struct cdns_plat_pcie {
25 	struct cdns_pcie        *pcie;
26 	bool is_rc;
27 };
28 
29 struct cdns_plat_pcie_of_data {
30 	bool is_rc;
31 };
32 
33 static const struct of_device_id cdns_plat_pcie_of_match[];
34 
cdns_plat_cpu_addr_fixup(struct cdns_pcie * pcie,u64 cpu_addr)35 static u64 cdns_plat_cpu_addr_fixup(struct cdns_pcie *pcie, u64 cpu_addr)
36 {
37 	return cpu_addr & CDNS_PLAT_CPU_TO_BUS_ADDR;
38 }
39 
40 static const struct cdns_pcie_ops cdns_plat_ops = {
41 	.cpu_addr_fixup = cdns_plat_cpu_addr_fixup,
42 };
43 
cdns_plat_pcie_probe(struct platform_device * pdev)44 static int cdns_plat_pcie_probe(struct platform_device *pdev)
45 {
46 	const struct cdns_plat_pcie_of_data *data;
47 	struct cdns_plat_pcie *cdns_plat_pcie;
48 	const struct of_device_id *match;
49 	struct device *dev = &pdev->dev;
50 	struct pci_host_bridge *bridge;
51 	struct cdns_pcie_ep *ep;
52 	struct cdns_pcie_rc *rc;
53 	int phy_count;
54 	bool is_rc;
55 	int ret;
56 
57 	match = of_match_device(cdns_plat_pcie_of_match, dev);
58 	if (!match)
59 		return -EINVAL;
60 
61 	data = (struct cdns_plat_pcie_of_data *)match->data;
62 	is_rc = data->is_rc;
63 
64 	pr_debug(" Started %s with is_rc: %d\n", __func__, is_rc);
65 	cdns_plat_pcie = devm_kzalloc(dev, sizeof(*cdns_plat_pcie), GFP_KERNEL);
66 	if (!cdns_plat_pcie)
67 		return -ENOMEM;
68 
69 	platform_set_drvdata(pdev, cdns_plat_pcie);
70 	if (is_rc) {
71 		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_HOST))
72 			return -ENODEV;
73 
74 		bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
75 		if (!bridge)
76 			return -ENOMEM;
77 
78 		rc = pci_host_bridge_priv(bridge);
79 		rc->pcie.dev = dev;
80 		rc->pcie.ops = &cdns_plat_ops;
81 		cdns_plat_pcie->pcie = &rc->pcie;
82 		cdns_plat_pcie->is_rc = is_rc;
83 
84 		ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
85 		if (ret) {
86 			dev_err(dev, "failed to init phy\n");
87 			return ret;
88 		}
89 		pm_runtime_enable(dev);
90 		ret = pm_runtime_get_sync(dev);
91 		if (ret < 0) {
92 			dev_err(dev, "pm_runtime_get_sync() failed\n");
93 			goto err_get_sync;
94 		}
95 
96 		ret = cdns_pcie_host_setup(rc);
97 		if (ret)
98 			goto err_init;
99 	} else {
100 		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_EP))
101 			return -ENODEV;
102 
103 		ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
104 		if (!ep)
105 			return -ENOMEM;
106 
107 		ep->pcie.dev = dev;
108 		ep->pcie.ops = &cdns_plat_ops;
109 		cdns_plat_pcie->pcie = &ep->pcie;
110 		cdns_plat_pcie->is_rc = is_rc;
111 
112 		ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
113 		if (ret) {
114 			dev_err(dev, "failed to init phy\n");
115 			return ret;
116 		}
117 
118 		pm_runtime_enable(dev);
119 		ret = pm_runtime_get_sync(dev);
120 		if (ret < 0) {
121 			dev_err(dev, "pm_runtime_get_sync() failed\n");
122 			goto err_get_sync;
123 		}
124 
125 		ret = cdns_pcie_ep_setup(ep);
126 		if (ret)
127 			goto err_init;
128 	}
129 
130  err_init:
131  err_get_sync:
132 	pm_runtime_put_sync(dev);
133 	pm_runtime_disable(dev);
134 	cdns_pcie_disable_phy(cdns_plat_pcie->pcie);
135 	phy_count = cdns_plat_pcie->pcie->phy_count;
136 	while (phy_count--)
137 		device_link_del(cdns_plat_pcie->pcie->link[phy_count]);
138 
139 	return 0;
140 }
141 
cdns_plat_pcie_shutdown(struct platform_device * pdev)142 static void cdns_plat_pcie_shutdown(struct platform_device *pdev)
143 {
144 	struct device *dev = &pdev->dev;
145 	struct cdns_pcie *pcie = dev_get_drvdata(dev);
146 	int ret;
147 
148 	ret = pm_runtime_put_sync(dev);
149 	if (ret < 0)
150 		dev_dbg(dev, "pm_runtime_put_sync failed\n");
151 
152 	pm_runtime_disable(dev);
153 
154 	cdns_pcie_disable_phy(pcie);
155 }
156 
157 static const struct cdns_plat_pcie_of_data cdns_plat_pcie_host_of_data = {
158 	.is_rc = true,
159 };
160 
161 static const struct cdns_plat_pcie_of_data cdns_plat_pcie_ep_of_data = {
162 	.is_rc = false,
163 };
164 
165 static const struct of_device_id cdns_plat_pcie_of_match[] = {
166 	{
167 		.compatible = "cdns,cdns-pcie-host",
168 		.data = &cdns_plat_pcie_host_of_data,
169 	},
170 	{
171 		.compatible = "cdns,cdns-pcie-ep",
172 		.data = &cdns_plat_pcie_ep_of_data,
173 	},
174 	{},
175 };
176 
177 static struct platform_driver cdns_plat_pcie_driver = {
178 	.driver = {
179 		.name = "cdns-pcie",
180 		.of_match_table = cdns_plat_pcie_of_match,
181 		.pm	= &cdns_pcie_pm_ops,
182 	},
183 	.probe = cdns_plat_pcie_probe,
184 	.shutdown = cdns_plat_pcie_shutdown,
185 };
186 builtin_platform_driver(cdns_plat_pcie_driver);
187