1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * AMD HSMP Platform Driver
4 * Copyright (c) 2022, AMD.
5 * All Rights Reserved.
6 *
7 * This file provides a device implementation for HSMP interface
8 */
9
10 #include <asm/amd_hsmp.h>
11 #include <asm/amd_nb.h>
12
13 #include <linux/acpi.h>
14 #include <linux/delay.h>
15 #include <linux/device.h>
16 #include <linux/semaphore.h>
17 #include <linux/sysfs.h>
18
19 #include "hsmp.h"
20
21 /* HSMP Status / Error codes */
22 #define HSMP_STATUS_NOT_READY 0x00
23 #define HSMP_STATUS_OK 0x01
24 #define HSMP_ERR_INVALID_MSG 0xFE
25 #define HSMP_ERR_INVALID_INPUT 0xFF
26 #define HSMP_ERR_PREREQ_NOT_SATISFIED 0xFD
27 #define HSMP_ERR_SMU_BUSY 0xFC
28
29 /* Timeout in millsec */
30 #define HSMP_MSG_TIMEOUT 100
31 #define HSMP_SHORT_SLEEP 1
32
33 #define HSMP_WR true
34 #define HSMP_RD false
35
36 #define DRIVER_VERSION "2.3"
37
38 static struct hsmp_plat_device hsmp_pdev;
39
40 /*
41 * Send a message to the HSMP port via PCI-e config space registers
42 * or by writing to MMIO space.
43 *
44 * The caller is expected to zero out any unused arguments.
45 * If a response is expected, the number of response words should be greater than 0.
46 *
47 * Returns 0 for success and populates the requested number of arguments.
48 * Returns a negative error code for failure.
49 */
__hsmp_send_message(struct hsmp_socket * sock,struct hsmp_message * msg)50 static int __hsmp_send_message(struct hsmp_socket *sock, struct hsmp_message *msg)
51 {
52 struct hsmp_mbaddr_info *mbinfo;
53 unsigned long timeout, short_sleep;
54 u32 mbox_status;
55 u32 index;
56 int ret;
57
58 mbinfo = &sock->mbinfo;
59
60 /* Clear the status register */
61 mbox_status = HSMP_STATUS_NOT_READY;
62 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_WR);
63 if (ret) {
64 dev_err(sock->dev, "Error %d clearing mailbox status register\n", ret);
65 return ret;
66 }
67
68 index = 0;
69 /* Write any message arguments */
70 while (index < msg->num_args) {
71 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
72 &msg->args[index], HSMP_WR);
73 if (ret) {
74 dev_err(sock->dev, "Error %d writing message argument %d\n", ret, index);
75 return ret;
76 }
77 index++;
78 }
79
80 /* Write the message ID which starts the operation */
81 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_id_off, &msg->msg_id, HSMP_WR);
82 if (ret) {
83 dev_err(sock->dev, "Error %d writing message ID %u\n", ret, msg->msg_id);
84 return ret;
85 }
86
87 /*
88 * Depending on when the trigger write completes relative to the SMU
89 * firmware 1 ms cycle, the operation may take from tens of us to 1 ms
90 * to complete. Some operations may take more. Therefore we will try
91 * a few short duration sleeps and switch to long sleeps if we don't
92 * succeed quickly.
93 */
94 short_sleep = jiffies + msecs_to_jiffies(HSMP_SHORT_SLEEP);
95 timeout = jiffies + msecs_to_jiffies(HSMP_MSG_TIMEOUT);
96
97 while (time_before(jiffies, timeout)) {
98 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_RD);
99 if (ret) {
100 dev_err(sock->dev, "Error %d reading mailbox status\n", ret);
101 return ret;
102 }
103
104 if (mbox_status != HSMP_STATUS_NOT_READY)
105 break;
106 if (time_before(jiffies, short_sleep))
107 usleep_range(50, 100);
108 else
109 usleep_range(1000, 2000);
110 }
111
112 if (unlikely(mbox_status == HSMP_STATUS_NOT_READY)) {
113 dev_err(sock->dev, "Message ID 0x%X failure : SMU tmeout (status = 0x%X)\n",
114 msg->msg_id, mbox_status);
115 return -ETIMEDOUT;
116 } else if (unlikely(mbox_status == HSMP_ERR_INVALID_MSG)) {
117 dev_err(sock->dev, "Message ID 0x%X failure : Invalid message (status = 0x%X)\n",
118 msg->msg_id, mbox_status);
119 return -ENOMSG;
120 } else if (unlikely(mbox_status == HSMP_ERR_INVALID_INPUT)) {
121 dev_err(sock->dev, "Message ID 0x%X failure : Invalid arguments (status = 0x%X)\n",
122 msg->msg_id, mbox_status);
123 return -EINVAL;
124 } else if (unlikely(mbox_status == HSMP_ERR_PREREQ_NOT_SATISFIED)) {
125 dev_err(sock->dev, "Message ID 0x%X failure : Prerequisite not satisfied (status = 0x%X)\n",
126 msg->msg_id, mbox_status);
127 return -EREMOTEIO;
128 } else if (unlikely(mbox_status == HSMP_ERR_SMU_BUSY)) {
129 dev_err(sock->dev, "Message ID 0x%X failure : SMU BUSY (status = 0x%X)\n",
130 msg->msg_id, mbox_status);
131 return -EBUSY;
132 } else if (unlikely(mbox_status != HSMP_STATUS_OK)) {
133 dev_err(sock->dev, "Message ID 0x%X unknown failure (status = 0x%X)\n",
134 msg->msg_id, mbox_status);
135 return -EIO;
136 }
137
138 /*
139 * SMU has responded OK. Read response data.
140 * SMU reads the input arguments from eight 32 bit registers starting
141 * from SMN_HSMP_MSG_DATA and writes the response data to the same
142 * SMN_HSMP_MSG_DATA address.
143 * We copy the response data if any, back to the args[].
144 */
145 index = 0;
146 while (index < msg->response_sz) {
147 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
148 &msg->args[index], HSMP_RD);
149 if (ret) {
150 dev_err(sock->dev, "Error %d reading response %u for message ID:%u\n",
151 ret, index, msg->msg_id);
152 break;
153 }
154 index++;
155 }
156
157 return ret;
158 }
159
validate_message(struct hsmp_message * msg)160 static int validate_message(struct hsmp_message *msg)
161 {
162 /* msg_id against valid range of message IDs */
163 if (msg->msg_id < HSMP_TEST || msg->msg_id >= HSMP_MSG_ID_MAX)
164 return -ENOMSG;
165
166 /* msg_id is a reserved message ID */
167 if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_RSVD)
168 return -ENOMSG;
169
170 /* num_args and response_sz against the HSMP spec */
171 if (msg->num_args != hsmp_msg_desc_table[msg->msg_id].num_args ||
172 msg->response_sz != hsmp_msg_desc_table[msg->msg_id].response_sz)
173 return -EINVAL;
174
175 return 0;
176 }
177
hsmp_send_message(struct hsmp_message * msg)178 int hsmp_send_message(struct hsmp_message *msg)
179 {
180 struct hsmp_socket *sock;
181 int ret;
182
183 if (!msg)
184 return -EINVAL;
185 ret = validate_message(msg);
186 if (ret)
187 return ret;
188
189 if (!hsmp_pdev.sock || msg->sock_ind >= hsmp_pdev.num_sockets)
190 return -ENODEV;
191 sock = &hsmp_pdev.sock[msg->sock_ind];
192
193 /*
194 * The time taken by smu operation to complete is between
195 * 10us to 1ms. Sometime it may take more time.
196 * In SMP system timeout of 100 millisecs should
197 * be enough for the previous thread to finish the operation
198 */
199 ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));
200 if (ret < 0)
201 return ret;
202
203 ret = __hsmp_send_message(sock, msg);
204
205 up(&sock->hsmp_sem);
206
207 return ret;
208 }
209 EXPORT_SYMBOL_NS_GPL(hsmp_send_message, "AMD_HSMP");
210
hsmp_test(u16 sock_ind,u32 value)211 int hsmp_test(u16 sock_ind, u32 value)
212 {
213 struct hsmp_message msg = { 0 };
214 int ret;
215
216 /*
217 * Test the hsmp port by performing TEST command. The test message
218 * takes one argument and returns the value of that argument + 1.
219 */
220 msg.msg_id = HSMP_TEST;
221 msg.num_args = 1;
222 msg.response_sz = 1;
223 msg.args[0] = value;
224 msg.sock_ind = sock_ind;
225
226 ret = hsmp_send_message(&msg);
227 if (ret)
228 return ret;
229
230 /* Check the response value */
231 if (msg.args[0] != (value + 1)) {
232 dev_err(hsmp_pdev.sock[sock_ind].dev,
233 "Socket %d test message failed, Expected 0x%08X, received 0x%08X\n",
234 sock_ind, (value + 1), msg.args[0]);
235 return -EBADE;
236 }
237
238 return ret;
239 }
240 EXPORT_SYMBOL_NS_GPL(hsmp_test, "AMD_HSMP");
241
hsmp_ioctl(struct file * fp,unsigned int cmd,unsigned long arg)242 long hsmp_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
243 {
244 int __user *arguser = (int __user *)arg;
245 struct hsmp_message msg = { 0 };
246 int ret;
247
248 if (copy_struct_from_user(&msg, sizeof(msg), arguser, sizeof(struct hsmp_message)))
249 return -EFAULT;
250
251 /*
252 * Check msg_id is within the range of supported msg ids
253 * i.e within the array bounds of hsmp_msg_desc_table
254 */
255 if (msg.msg_id < HSMP_TEST || msg.msg_id >= HSMP_MSG_ID_MAX)
256 return -ENOMSG;
257
258 switch (fp->f_mode & (FMODE_WRITE | FMODE_READ)) {
259 case FMODE_WRITE:
260 /*
261 * Device is opened in O_WRONLY mode
262 * Execute only set/configure commands
263 */
264 if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_SET)
265 return -EPERM;
266 break;
267 case FMODE_READ:
268 /*
269 * Device is opened in O_RDONLY mode
270 * Execute only get/monitor commands
271 */
272 if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_GET)
273 return -EPERM;
274 break;
275 case FMODE_READ | FMODE_WRITE:
276 /*
277 * Device is opened in O_RDWR mode
278 * Execute both get/monitor and set/configure commands
279 */
280 break;
281 default:
282 return -EPERM;
283 }
284
285 ret = hsmp_send_message(&msg);
286 if (ret)
287 return ret;
288
289 if (hsmp_msg_desc_table[msg.msg_id].response_sz > 0) {
290 /* Copy results back to user for get/monitor commands */
291 if (copy_to_user(arguser, &msg, sizeof(struct hsmp_message)))
292 return -EFAULT;
293 }
294
295 return 0;
296 }
297
hsmp_metric_tbl_read(struct hsmp_socket * sock,char * buf,size_t size)298 ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size)
299 {
300 struct hsmp_message msg = { 0 };
301 int ret;
302
303 if (!sock || !buf)
304 return -EINVAL;
305
306 /* Do not support lseek(), also don't allow more than the size of metric table */
307 if (size != sizeof(struct hsmp_metric_table)) {
308 dev_err(sock->dev, "Wrong buffer size\n");
309 return -EINVAL;
310 }
311
312 msg.msg_id = HSMP_GET_METRIC_TABLE;
313 msg.sock_ind = sock->sock_ind;
314
315 ret = hsmp_send_message(&msg);
316 if (ret)
317 return ret;
318 memcpy_fromio(buf, sock->metric_tbl_addr, size);
319
320 return size;
321 }
322 EXPORT_SYMBOL_NS_GPL(hsmp_metric_tbl_read, "AMD_HSMP");
323
hsmp_get_tbl_dram_base(u16 sock_ind)324 int hsmp_get_tbl_dram_base(u16 sock_ind)
325 {
326 struct hsmp_socket *sock = &hsmp_pdev.sock[sock_ind];
327 struct hsmp_message msg = { 0 };
328 phys_addr_t dram_addr;
329 int ret;
330
331 msg.sock_ind = sock_ind;
332 msg.response_sz = hsmp_msg_desc_table[HSMP_GET_METRIC_TABLE_DRAM_ADDR].response_sz;
333 msg.msg_id = HSMP_GET_METRIC_TABLE_DRAM_ADDR;
334
335 ret = hsmp_send_message(&msg);
336 if (ret)
337 return ret;
338
339 /*
340 * calculate the metric table DRAM address from lower and upper 32 bits
341 * sent from SMU and ioremap it to virtual address.
342 */
343 dram_addr = msg.args[0] | ((u64)(msg.args[1]) << 32);
344 if (!dram_addr) {
345 dev_err(sock->dev, "Invalid DRAM address for metric table\n");
346 return -ENOMEM;
347 }
348 sock->metric_tbl_addr = devm_ioremap(sock->dev, dram_addr,
349 sizeof(struct hsmp_metric_table));
350 if (!sock->metric_tbl_addr) {
351 dev_err(sock->dev, "Failed to ioremap metric table addr\n");
352 return -ENOMEM;
353 }
354 return 0;
355 }
356 EXPORT_SYMBOL_NS_GPL(hsmp_get_tbl_dram_base, "AMD_HSMP");
357
hsmp_cache_proto_ver(u16 sock_ind)358 int hsmp_cache_proto_ver(u16 sock_ind)
359 {
360 struct hsmp_message msg = { 0 };
361 int ret;
362
363 msg.msg_id = HSMP_GET_PROTO_VER;
364 msg.sock_ind = sock_ind;
365 msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz;
366
367 ret = hsmp_send_message(&msg);
368 if (!ret)
369 hsmp_pdev.proto_ver = msg.args[0];
370
371 return ret;
372 }
373 EXPORT_SYMBOL_NS_GPL(hsmp_cache_proto_ver, "AMD_HSMP");
374
375 static const struct file_operations hsmp_fops = {
376 .owner = THIS_MODULE,
377 .unlocked_ioctl = hsmp_ioctl,
378 .compat_ioctl = hsmp_ioctl,
379 };
380
hsmp_misc_register(struct device * dev)381 int hsmp_misc_register(struct device *dev)
382 {
383 hsmp_pdev.mdev.name = HSMP_CDEV_NAME;
384 hsmp_pdev.mdev.minor = MISC_DYNAMIC_MINOR;
385 hsmp_pdev.mdev.fops = &hsmp_fops;
386 hsmp_pdev.mdev.parent = dev;
387 hsmp_pdev.mdev.nodename = HSMP_DEVNODE_NAME;
388 hsmp_pdev.mdev.mode = 0644;
389
390 return misc_register(&hsmp_pdev.mdev);
391 }
392 EXPORT_SYMBOL_NS_GPL(hsmp_misc_register, "AMD_HSMP");
393
hsmp_misc_deregister(void)394 void hsmp_misc_deregister(void)
395 {
396 misc_deregister(&hsmp_pdev.mdev);
397 }
398 EXPORT_SYMBOL_NS_GPL(hsmp_misc_deregister, "AMD_HSMP");
399
get_hsmp_pdev(void)400 struct hsmp_plat_device *get_hsmp_pdev(void)
401 {
402 return &hsmp_pdev;
403 }
404 EXPORT_SYMBOL_NS_GPL(get_hsmp_pdev, "AMD_HSMP");
405
406 MODULE_DESCRIPTION("AMD HSMP Common driver");
407 MODULE_VERSION(DRIVER_VERSION);
408 MODULE_LICENSE("GPL");
409