xref: /openbmc/linux/drivers/cdx/controller/cdx_controller.c (revision 8a7923df35d3a0fa44985148cee5b7fde4a370ba)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * CDX host controller driver for AMD versal-net platform.
4  *
5  * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
6  */
7 
8 #include <linux/of_platform.h>
9 #include <linux/slab.h>
10 #include <linux/cdx/cdx_bus.h>
11 
12 #include "../cdx.h"
13 #include "mcdi_functions.h"
14 #include "mcdi.h"
15 
16 static unsigned int cdx_mcdi_rpc_timeout(struct cdx_mcdi *cdx, unsigned int cmd)
17 {
18 	return MCDI_RPC_TIMEOUT;
19 }
20 
21 static void cdx_mcdi_request(struct cdx_mcdi *cdx,
22 			     const struct cdx_dword *hdr, size_t hdr_len,
23 			     const struct cdx_dword *sdu, size_t sdu_len)
24 {
25 	/*
26 	 * This will get updated by rpmsg APIs, with RPMSG introduction
27 	 * in CDX controller as a transport layer.
28 	 */
29 }
30 
31 static const struct cdx_mcdi_ops mcdi_ops = {
32 	.mcdi_rpc_timeout = cdx_mcdi_rpc_timeout,
33 	.mcdi_request = cdx_mcdi_request,
34 };
35 
36 static int cdx_scan_devices(struct cdx_controller *cdx)
37 {
38 	struct cdx_mcdi *cdx_mcdi = cdx->priv;
39 	u8 bus_num, dev_num, num_cdx_bus;
40 	int ret;
41 
42 	/* MCDI FW Read: Fetch the number of CDX buses on this controller */
43 	ret = cdx_mcdi_get_num_buses(cdx_mcdi);
44 	if (ret < 0) {
45 		dev_err(cdx->dev,
46 			"Get number of CDX buses failed: %d\n", ret);
47 		return ret;
48 	}
49 	num_cdx_bus = (u8)ret;
50 
51 	for (bus_num = 0; bus_num < num_cdx_bus; bus_num++) {
52 		u8 num_cdx_dev;
53 
54 		/* MCDI FW Read: Fetch the number of devices present */
55 		ret = cdx_mcdi_get_num_devs(cdx_mcdi, bus_num);
56 		if (ret < 0) {
57 			dev_err(cdx->dev,
58 				"Get devices on CDX bus %d failed: %d\n", bus_num, ret);
59 			continue;
60 		}
61 		num_cdx_dev = (u8)ret;
62 
63 		for (dev_num = 0; dev_num < num_cdx_dev; dev_num++) {
64 			struct cdx_dev_params dev_params;
65 
66 			/* MCDI FW: Get the device config */
67 			ret = cdx_mcdi_get_dev_config(cdx_mcdi, bus_num,
68 						      dev_num, &dev_params);
69 			if (ret) {
70 				dev_err(cdx->dev,
71 					"CDX device config get failed for %d(bus):%d(dev), %d\n",
72 					bus_num, dev_num, ret);
73 				continue;
74 			}
75 			dev_params.cdx = cdx;
76 
77 			/* Add the device to the cdx bus */
78 			ret = cdx_device_add(&dev_params);
79 			if (ret) {
80 				dev_err(cdx->dev, "registering cdx dev: %d failed: %d\n",
81 					dev_num, ret);
82 				continue;
83 			}
84 
85 			dev_dbg(cdx->dev, "CDX dev: %d on cdx bus: %d created\n",
86 				dev_num, bus_num);
87 		}
88 	}
89 
90 	return 0;
91 }
92 
93 static struct cdx_ops cdx_ops = {
94 	.scan		= cdx_scan_devices,
95 };
96 
97 static int xlnx_cdx_probe(struct platform_device *pdev)
98 {
99 	struct cdx_controller *cdx;
100 	struct cdx_mcdi *cdx_mcdi;
101 	int ret;
102 
103 	cdx_mcdi = kzalloc(sizeof(*cdx_mcdi), GFP_KERNEL);
104 	if (!cdx_mcdi)
105 		return -ENOMEM;
106 
107 	/* Store the MCDI ops */
108 	cdx_mcdi->mcdi_ops = &mcdi_ops;
109 	/* MCDI FW: Initialize the FW path */
110 	ret = cdx_mcdi_init(cdx_mcdi);
111 	if (ret) {
112 		dev_err_probe(&pdev->dev, ret, "MCDI Initialization failed\n");
113 		goto mcdi_init_fail;
114 	}
115 
116 	cdx = kzalloc(sizeof(*cdx), GFP_KERNEL);
117 	if (!cdx) {
118 		ret = -ENOMEM;
119 		goto cdx_alloc_fail;
120 	}
121 	platform_set_drvdata(pdev, cdx);
122 
123 	cdx->dev = &pdev->dev;
124 	cdx->priv = cdx_mcdi;
125 	cdx->ops = &cdx_ops;
126 
127 	return 0;
128 
129 cdx_alloc_fail:
130 	cdx_mcdi_finish(cdx_mcdi);
131 mcdi_init_fail:
132 	kfree(cdx_mcdi);
133 
134 	return ret;
135 }
136 
137 static int xlnx_cdx_remove(struct platform_device *pdev)
138 {
139 	struct cdx_controller *cdx = platform_get_drvdata(pdev);
140 	struct cdx_mcdi *cdx_mcdi = cdx->priv;
141 
142 	kfree(cdx);
143 
144 	cdx_mcdi_finish(cdx_mcdi);
145 	kfree(cdx_mcdi);
146 
147 	return 0;
148 }
149 
150 static const struct of_device_id cdx_match_table[] = {
151 	{.compatible = "xlnx,versal-net-cdx",},
152 	{ },
153 };
154 
155 MODULE_DEVICE_TABLE(of, cdx_match_table);
156 
157 static struct platform_driver cdx_pdriver = {
158 	.driver = {
159 		   .name = "cdx-controller",
160 		   .pm = NULL,
161 		   .of_match_table = cdx_match_table,
162 		   },
163 	.probe = xlnx_cdx_probe,
164 	.remove = xlnx_cdx_remove,
165 };
166 
167 static int __init cdx_controller_init(void)
168 {
169 	int ret;
170 
171 	ret = platform_driver_register(&cdx_pdriver);
172 	if (ret)
173 		pr_err("platform_driver_register() failed: %d\n", ret);
174 
175 	return ret;
176 }
177 
178 static void __exit cdx_controller_exit(void)
179 {
180 	platform_driver_unregister(&cdx_pdriver);
181 }
182 
183 module_init(cdx_controller_init);
184 module_exit(cdx_controller_exit);
185 
186 MODULE_AUTHOR("AMD Inc.");
187 MODULE_DESCRIPTION("CDX controller for AMD devices");
188 MODULE_LICENSE("GPL");
189