xref: /linux/drivers/platform/x86/amd/hsmp/plat.c (revision c34e9ab9a612ee8b18273398ef75c207b01f516d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AMD HSMP Platform Driver
4  * Copyright (c) 2024, AMD.
5  * All Rights Reserved.
6  *
7  * This file provides platform device implementations.
8  */
9 
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 
12 #include <asm/amd_hsmp.h>
13 #include <asm/amd_nb.h>
14 
15 #include <linux/device.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19 #include <linux/sysfs.h>
20 
21 #include "hsmp.h"
22 
23 #define DRIVER_NAME		"amd_hsmp"
24 #define DRIVER_VERSION		"2.3"
25 
26 /*
27  * To access specific HSMP mailbox register, s/w writes the SMN address of HSMP mailbox
28  * register into the SMN_INDEX register, and reads/writes the SMN_DATA reg.
29  * Below are required SMN address for HSMP Mailbox register offsets in SMU address space
30  */
31 #define SMN_HSMP_BASE		0x3B00000
32 #define SMN_HSMP_MSG_ID		0x0010534
33 #define SMN_HSMP_MSG_ID_F1A_M0H	0x0010934
34 #define SMN_HSMP_MSG_RESP	0x0010980
35 #define SMN_HSMP_MSG_DATA	0x00109E0
36 
37 #define HSMP_INDEX_REG		0xc4
38 #define HSMP_DATA_REG		0xc8
39 
40 static struct hsmp_plat_device *hsmp_pdev;
41 
42 static int amd_hsmp_pci_rdwr(struct hsmp_socket *sock, u32 offset,
43 			     u32 *value, bool write)
44 {
45 	int ret;
46 
47 	if (!sock->root)
48 		return -ENODEV;
49 
50 	ret = pci_write_config_dword(sock->root, HSMP_INDEX_REG,
51 				     sock->mbinfo.base_addr + offset);
52 	if (ret)
53 		return ret;
54 
55 	ret = (write ? pci_write_config_dword(sock->root, HSMP_DATA_REG, *value)
56 		     : pci_read_config_dword(sock->root, HSMP_DATA_REG, value));
57 
58 	return ret;
59 }
60 
61 static ssize_t hsmp_metric_tbl_plat_read(struct file *filp, struct kobject *kobj,
62 					 struct bin_attribute *bin_attr, char *buf,
63 					 loff_t off, size_t count)
64 {
65 	struct hsmp_socket *sock;
66 	u16 sock_ind;
67 
68 	sock_ind = (uintptr_t)bin_attr->private;
69 	if (sock_ind >= hsmp_pdev->num_sockets)
70 		return -EINVAL;
71 
72 	sock = &hsmp_pdev->sock[sock_ind];
73 
74 	return hsmp_metric_tbl_read(sock, buf, count);
75 }
76 
77 static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
78 					 const struct bin_attribute *battr, int id)
79 {
80 	u16 sock_ind;
81 
82 	sock_ind = (uintptr_t)battr->private;
83 
84 	if (id == 0 && sock_ind >= hsmp_pdev->num_sockets)
85 		return SYSFS_GROUP_INVISIBLE;
86 
87 	if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6)
88 		return battr->attr.mode;
89 
90 	return 0;
91 }
92 
93 /*
94  * AMD supports maximum of 8 sockets in a system.
95  * Static array of 8 + 1(for NULL) elements is created below
96  * to create sysfs groups for sockets.
97  * is_bin_visible function is used to show / hide the necessary groups.
98  */
99 #define HSMP_BIN_ATTR(index, _list)					\
100 static struct bin_attribute attr##index = {				\
101 	.attr = { .name = HSMP_METRICS_TABLE_NAME, .mode = 0444},	\
102 	.private = (void *)index,					\
103 	.read = hsmp_metric_tbl_plat_read,					\
104 	.size = sizeof(struct hsmp_metric_table),			\
105 };									\
106 static struct bin_attribute _list[] = {					\
107 	&attr##index,							\
108 	NULL								\
109 }
110 
111 HSMP_BIN_ATTR(0, *sock0_attr_list);
112 HSMP_BIN_ATTR(1, *sock1_attr_list);
113 HSMP_BIN_ATTR(2, *sock2_attr_list);
114 HSMP_BIN_ATTR(3, *sock3_attr_list);
115 HSMP_BIN_ATTR(4, *sock4_attr_list);
116 HSMP_BIN_ATTR(5, *sock5_attr_list);
117 HSMP_BIN_ATTR(6, *sock6_attr_list);
118 HSMP_BIN_ATTR(7, *sock7_attr_list);
119 
120 #define HSMP_BIN_ATTR_GRP(index, _list, _name)			\
121 static struct attribute_group sock##index##_attr_grp = {	\
122 	.bin_attrs = _list,					\
123 	.is_bin_visible = hsmp_is_sock_attr_visible,		\
124 	.name = #_name,						\
125 }
126 
127 HSMP_BIN_ATTR_GRP(0, sock0_attr_list, socket0);
128 HSMP_BIN_ATTR_GRP(1, sock1_attr_list, socket1);
129 HSMP_BIN_ATTR_GRP(2, sock2_attr_list, socket2);
130 HSMP_BIN_ATTR_GRP(3, sock3_attr_list, socket3);
131 HSMP_BIN_ATTR_GRP(4, sock4_attr_list, socket4);
132 HSMP_BIN_ATTR_GRP(5, sock5_attr_list, socket5);
133 HSMP_BIN_ATTR_GRP(6, sock6_attr_list, socket6);
134 HSMP_BIN_ATTR_GRP(7, sock7_attr_list, socket7);
135 
136 static const struct attribute_group *hsmp_groups[] = {
137 	&sock0_attr_grp,
138 	&sock1_attr_grp,
139 	&sock2_attr_grp,
140 	&sock3_attr_grp,
141 	&sock4_attr_grp,
142 	&sock5_attr_grp,
143 	&sock6_attr_grp,
144 	&sock7_attr_grp,
145 	NULL
146 };
147 
148 static inline bool is_f1a_m0h(void)
149 {
150 	if (boot_cpu_data.x86 == 0x1A && boot_cpu_data.x86_model <= 0x0F)
151 		return true;
152 
153 	return false;
154 }
155 
156 static int init_platform_device(struct device *dev)
157 {
158 	struct hsmp_socket *sock;
159 	int ret, i;
160 
161 	for (i = 0; i < hsmp_pdev->num_sockets; i++) {
162 		if (!node_to_amd_nb(i))
163 			return -ENODEV;
164 		sock = &hsmp_pdev->sock[i];
165 		sock->root			= node_to_amd_nb(i)->root;
166 		sock->sock_ind			= i;
167 		sock->dev			= dev;
168 		sock->mbinfo.base_addr		= SMN_HSMP_BASE;
169 		sock->amd_hsmp_rdwr		= amd_hsmp_pci_rdwr;
170 
171 		/*
172 		 * This is a transitional change from non-ACPI to ACPI, only
173 		 * family 0x1A, model 0x00 platform is supported for both ACPI and non-ACPI.
174 		 */
175 		if (is_f1a_m0h())
176 			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID_F1A_M0H;
177 		else
178 			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID;
179 
180 		sock->mbinfo.msg_resp_off	= SMN_HSMP_MSG_RESP;
181 		sock->mbinfo.msg_arg_off	= SMN_HSMP_MSG_DATA;
182 		sema_init(&sock->hsmp_sem, 1);
183 
184 		/* Test the hsmp interface on each socket */
185 		ret = hsmp_test(i, 0xDEADBEEF);
186 		if (ret) {
187 			dev_err(dev, "HSMP test message failed on Fam:%x model:%x\n",
188 				boot_cpu_data.x86, boot_cpu_data.x86_model);
189 			dev_err(dev, "Is HSMP disabled in BIOS ?\n");
190 			return ret;
191 		}
192 
193 		ret = hsmp_cache_proto_ver(i);
194 		if (ret) {
195 			dev_err(dev, "Failed to read HSMP protocol version\n");
196 			return ret;
197 		}
198 
199 		if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6) {
200 			ret = hsmp_get_tbl_dram_base(i);
201 			if (ret)
202 				dev_err(dev, "Failed to init metric table\n");
203 		}
204 	}
205 
206 	return 0;
207 }
208 
209 static int hsmp_pltdrv_probe(struct platform_device *pdev)
210 {
211 	int ret;
212 
213 	hsmp_pdev->sock = devm_kcalloc(&pdev->dev, hsmp_pdev->num_sockets,
214 				       sizeof(*hsmp_pdev->sock),
215 				       GFP_KERNEL);
216 	if (!hsmp_pdev->sock)
217 		return -ENOMEM;
218 
219 	ret = init_platform_device(&pdev->dev);
220 	if (ret) {
221 		dev_err(&pdev->dev, "Failed to init HSMP mailbox\n");
222 		return ret;
223 	}
224 
225 	return hsmp_misc_register(&pdev->dev);
226 }
227 
228 static void hsmp_pltdrv_remove(struct platform_device *pdev)
229 {
230 	hsmp_misc_deregister();
231 }
232 
233 static struct platform_driver amd_hsmp_driver = {
234 	.probe		= hsmp_pltdrv_probe,
235 	.remove		= hsmp_pltdrv_remove,
236 	.driver		= {
237 		.name	= DRIVER_NAME,
238 		.dev_groups = hsmp_groups,
239 	},
240 };
241 
242 static struct platform_device *amd_hsmp_platdev;
243 
244 static int hsmp_plat_dev_register(void)
245 {
246 	int ret;
247 
248 	amd_hsmp_platdev = platform_device_alloc(DRIVER_NAME, PLATFORM_DEVID_NONE);
249 	if (!amd_hsmp_platdev)
250 		return -ENOMEM;
251 
252 	ret = platform_device_add(amd_hsmp_platdev);
253 	if (ret)
254 		platform_device_put(amd_hsmp_platdev);
255 
256 	return ret;
257 }
258 
259 /*
260  * This check is only needed for backward compatibility of previous platforms.
261  * All new platforms are expected to support ACPI based probing.
262  */
263 static bool legacy_hsmp_support(void)
264 {
265 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
266 		return false;
267 
268 	switch (boot_cpu_data.x86) {
269 	case 0x19:
270 		switch (boot_cpu_data.x86_model) {
271 		case 0x00 ... 0x1F:
272 		case 0x30 ... 0x3F:
273 		case 0x90 ... 0x9F:
274 		case 0xA0 ... 0xAF:
275 			return true;
276 		default:
277 			return false;
278 		}
279 	case 0x1A:
280 		switch (boot_cpu_data.x86_model) {
281 		case 0x00 ... 0x1F:
282 			return true;
283 		default:
284 			return false;
285 		}
286 	default:
287 		return false;
288 	}
289 
290 	return false;
291 }
292 
293 static int __init hsmp_plt_init(void)
294 {
295 	int ret = -ENODEV;
296 
297 	if (!legacy_hsmp_support()) {
298 		pr_info("HSMP is not supported on Family:%x model:%x\n",
299 			boot_cpu_data.x86, boot_cpu_data.x86_model);
300 		return ret;
301 	}
302 
303 	hsmp_pdev = get_hsmp_pdev();
304 	if (!hsmp_pdev)
305 		return -ENOMEM;
306 
307 	/*
308 	 * amd_nb_num() returns number of SMN/DF interfaces present in the system
309 	 * if we have N SMN/DF interfaces that ideally means N sockets
310 	 */
311 	hsmp_pdev->num_sockets = amd_nb_num();
312 	if (hsmp_pdev->num_sockets == 0 || hsmp_pdev->num_sockets > MAX_AMD_SOCKETS)
313 		return ret;
314 
315 	ret = platform_driver_register(&amd_hsmp_driver);
316 	if (ret)
317 		return ret;
318 
319 	ret = hsmp_plat_dev_register();
320 	if (ret)
321 		platform_driver_unregister(&amd_hsmp_driver);
322 
323 	return ret;
324 }
325 
326 static void __exit hsmp_plt_exit(void)
327 {
328 	platform_device_unregister(amd_hsmp_platdev);
329 	platform_driver_unregister(&amd_hsmp_driver);
330 }
331 
332 device_initcall(hsmp_plt_init);
333 module_exit(hsmp_plt_exit);
334 
335 MODULE_IMPORT_NS(AMD_HSMP);
336 MODULE_DESCRIPTION("AMD HSMP Platform Interface Driver");
337 MODULE_VERSION(DRIVER_VERSION);
338 MODULE_LICENSE("GPL");
339