1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (c) 2021 Intel Corporation
3
4 #include <linux/bug.h>
5 #include <linux/export.h>
6 #include <linux/pci.h>
7 #include <linux/peci.h>
8 #include <linux/slab.h>
9 #include <linux/types.h>
10
11 #include <asm/unaligned.h>
12
13 #include "internal.h"
14
15 #define PECI_GET_DIB_CMD 0xf7
16 #define PECI_GET_DIB_WR_LEN 1
17 #define PECI_GET_DIB_RD_LEN 8
18
19 #define PECI_GET_TEMP_CMD 0x01
20 #define PECI_GET_TEMP_WR_LEN 1
21 #define PECI_GET_TEMP_RD_LEN 2
22
23 #define PECI_RDPKGCFG_CMD 0xa1
24 #define PECI_RDPKGCFG_WR_LEN 5
25 #define PECI_RDPKGCFG_RD_LEN_BASE 1
26 #define PECI_WRPKGCFG_CMD 0xa5
27 #define PECI_WRPKGCFG_WR_LEN_BASE 6
28 #define PECI_WRPKGCFG_RD_LEN 1
29
30 #define PECI_RDIAMSR_CMD 0xb1
31 #define PECI_RDIAMSR_WR_LEN 5
32 #define PECI_RDIAMSR_RD_LEN 9
33 #define PECI_WRIAMSR_CMD 0xb5
34 #define PECI_RDIAMSREX_CMD 0xd1
35 #define PECI_RDIAMSREX_WR_LEN 6
36 #define PECI_RDIAMSREX_RD_LEN 9
37
38 #define PECI_RDPCICFG_CMD 0x61
39 #define PECI_RDPCICFG_WR_LEN 6
40 #define PECI_RDPCICFG_RD_LEN 5
41 #define PECI_RDPCICFG_RD_LEN_MAX 24
42 #define PECI_WRPCICFG_CMD 0x65
43
44 #define PECI_RDPCICFGLOCAL_CMD 0xe1
45 #define PECI_RDPCICFGLOCAL_WR_LEN 5
46 #define PECI_RDPCICFGLOCAL_RD_LEN_BASE 1
47 #define PECI_WRPCICFGLOCAL_CMD 0xe5
48 #define PECI_WRPCICFGLOCAL_WR_LEN_BASE 6
49 #define PECI_WRPCICFGLOCAL_RD_LEN 1
50
51 #define PECI_ENDPTCFG_TYPE_LOCAL_PCI 0x03
52 #define PECI_ENDPTCFG_TYPE_PCI 0x04
53 #define PECI_ENDPTCFG_TYPE_MMIO 0x05
54 #define PECI_ENDPTCFG_ADDR_TYPE_PCI 0x04
55 #define PECI_ENDPTCFG_ADDR_TYPE_MMIO_D 0x05
56 #define PECI_ENDPTCFG_ADDR_TYPE_MMIO_Q 0x06
57 #define PECI_RDENDPTCFG_CMD 0xc1
58 #define PECI_RDENDPTCFG_PCI_WR_LEN 12
59 #define PECI_RDENDPTCFG_MMIO_WR_LEN_BASE 10
60 #define PECI_RDENDPTCFG_MMIO_D_WR_LEN 14
61 #define PECI_RDENDPTCFG_MMIO_Q_WR_LEN 18
62 #define PECI_RDENDPTCFG_RD_LEN_BASE 1
63 #define PECI_WRENDPTCFG_CMD 0xc5
64 #define PECI_WRENDPTCFG_PCI_WR_LEN_BASE 13
65 #define PECI_WRENDPTCFG_MMIO_D_WR_LEN_BASE 15
66 #define PECI_WRENDPTCFG_MMIO_Q_WR_LEN_BASE 19
67 #define PECI_WRENDPTCFG_RD_LEN 1
68
69 /* Device Specific Completion Code (CC) Definition */
70 #define PECI_CC_SUCCESS 0x40
71 #define PECI_CC_NEED_RETRY 0x80
72 #define PECI_CC_OUT_OF_RESOURCE 0x81
73 #define PECI_CC_UNAVAIL_RESOURCE 0x82
74 #define PECI_CC_INVALID_REQ 0x90
75 #define PECI_CC_MCA_ERROR 0x91
76 #define PECI_CC_CATASTROPHIC_MCA_ERROR 0x93
77 #define PECI_CC_FATAL_MCA_ERROR 0x94
78 #define PECI_CC_PARITY_ERR_GPSB_OR_PMSB 0x98
79 #define PECI_CC_PARITY_ERR_GPSB_OR_PMSB_IERR 0x9B
80 #define PECI_CC_PARITY_ERR_GPSB_OR_PMSB_MCA 0x9C
81
82 #define PECI_RETRY_BIT BIT(0)
83
84 #define PECI_RETRY_TIMEOUT msecs_to_jiffies(700)
85 #define PECI_RETRY_INTERVAL_MIN msecs_to_jiffies(1)
86 #define PECI_RETRY_INTERVAL_MAX msecs_to_jiffies(128)
87
peci_request_data_cc(struct peci_request * req)88 static u8 peci_request_data_cc(struct peci_request *req)
89 {
90 return req->rx.buf[0];
91 }
92
93 /**
94 * peci_request_status() - return -errno based on PECI completion code
95 * @req: the PECI request that contains response data with completion code
96 *
97 * It can't be used for Ping(), GetDIB() and GetTemp() - for those commands we
98 * don't expect completion code in the response.
99 *
100 * Return: -errno
101 */
peci_request_status(struct peci_request * req)102 int peci_request_status(struct peci_request *req)
103 {
104 u8 cc = peci_request_data_cc(req);
105
106 if (cc != PECI_CC_SUCCESS)
107 dev_dbg(&req->device->dev, "ret: %#02x\n", cc);
108
109 switch (cc) {
110 case PECI_CC_SUCCESS:
111 return 0;
112 case PECI_CC_NEED_RETRY:
113 case PECI_CC_OUT_OF_RESOURCE:
114 case PECI_CC_UNAVAIL_RESOURCE:
115 return -EAGAIN;
116 case PECI_CC_INVALID_REQ:
117 return -EINVAL;
118 case PECI_CC_MCA_ERROR:
119 case PECI_CC_CATASTROPHIC_MCA_ERROR:
120 case PECI_CC_FATAL_MCA_ERROR:
121 case PECI_CC_PARITY_ERR_GPSB_OR_PMSB:
122 case PECI_CC_PARITY_ERR_GPSB_OR_PMSB_IERR:
123 case PECI_CC_PARITY_ERR_GPSB_OR_PMSB_MCA:
124 return -EIO;
125 }
126
127 WARN_ONCE(1, "Unknown PECI completion code: %#02x\n", cc);
128
129 return -EIO;
130 }
131 EXPORT_SYMBOL_NS_GPL(peci_request_status, PECI);
132
peci_request_xfer(struct peci_request * req)133 static int peci_request_xfer(struct peci_request *req)
134 {
135 struct peci_device *device = req->device;
136 struct peci_controller *controller = to_peci_controller(device->dev.parent);
137 int ret;
138
139 mutex_lock(&controller->bus_lock);
140 ret = controller->ops->xfer(controller, device->addr, req);
141 mutex_unlock(&controller->bus_lock);
142
143 return ret;
144 }
145
peci_request_xfer_retry(struct peci_request * req)146 static int peci_request_xfer_retry(struct peci_request *req)
147 {
148 long wait_interval = PECI_RETRY_INTERVAL_MIN;
149 struct peci_device *device = req->device;
150 struct peci_controller *controller = to_peci_controller(device->dev.parent);
151 unsigned long start = jiffies;
152 int ret;
153
154 /* Don't try to use it for ping */
155 if (WARN_ON(req->tx.len == 0))
156 return 0;
157
158 do {
159 ret = peci_request_xfer(req);
160 if (ret) {
161 dev_dbg(&controller->dev, "xfer error: %d\n", ret);
162 return ret;
163 }
164
165 if (peci_request_status(req) != -EAGAIN)
166 return 0;
167
168 /* Set the retry bit to indicate a retry attempt */
169 req->tx.buf[1] |= PECI_RETRY_BIT;
170
171 if (schedule_timeout_interruptible(wait_interval))
172 return -ERESTARTSYS;
173
174 wait_interval = min_t(long, wait_interval * 2, PECI_RETRY_INTERVAL_MAX);
175 } while (time_before(jiffies, start + PECI_RETRY_TIMEOUT));
176
177 dev_dbg(&controller->dev, "request timed out\n");
178
179 return -ETIMEDOUT;
180 }
181
182 /**
183 * peci_request_alloc() - allocate &struct peci_requests
184 * @device: PECI device to which request is going to be sent
185 * @tx_len: TX length
186 * @rx_len: RX length
187 *
188 * Return: A pointer to a newly allocated &struct peci_request on success or NULL otherwise.
189 */
peci_request_alloc(struct peci_device * device,u8 tx_len,u8 rx_len)190 struct peci_request *peci_request_alloc(struct peci_device *device, u8 tx_len, u8 rx_len)
191 {
192 struct peci_request *req;
193
194 /*
195 * TX and RX buffers are fixed length members of peci_request, this is
196 * just a warn for developers to make sure to expand the buffers (or
197 * change the allocation method) if we go over the current limit.
198 */
199 if (WARN_ON_ONCE(tx_len > PECI_REQUEST_MAX_BUF_SIZE || rx_len > PECI_REQUEST_MAX_BUF_SIZE))
200 return NULL;
201 /*
202 * PECI controllers that we are using now don't support DMA, this
203 * should be converted to DMA API once support for controllers that do
204 * allow it is added to avoid an extra copy.
205 */
206 req = kzalloc(sizeof(*req), GFP_KERNEL);
207 if (!req)
208 return NULL;
209
210 req->device = device;
211 req->tx.len = tx_len;
212 req->rx.len = rx_len;
213
214 return req;
215 }
216 EXPORT_SYMBOL_NS_GPL(peci_request_alloc, PECI);
217
218 /**
219 * peci_request_free() - free peci_request
220 * @req: the PECI request to be freed
221 */
peci_request_free(struct peci_request * req)222 void peci_request_free(struct peci_request *req)
223 {
224 kfree(req);
225 }
226 EXPORT_SYMBOL_NS_GPL(peci_request_free, PECI);
227
peci_xfer_get_dib(struct peci_device * device)228 struct peci_request *peci_xfer_get_dib(struct peci_device *device)
229 {
230 struct peci_request *req;
231 int ret;
232
233 req = peci_request_alloc(device, PECI_GET_DIB_WR_LEN, PECI_GET_DIB_RD_LEN);
234 if (!req)
235 return ERR_PTR(-ENOMEM);
236
237 req->tx.buf[0] = PECI_GET_DIB_CMD;
238
239 ret = peci_request_xfer(req);
240 if (ret) {
241 peci_request_free(req);
242 return ERR_PTR(ret);
243 }
244
245 return req;
246 }
247 EXPORT_SYMBOL_NS_GPL(peci_xfer_get_dib, PECI);
248
peci_xfer_get_temp(struct peci_device * device)249 struct peci_request *peci_xfer_get_temp(struct peci_device *device)
250 {
251 struct peci_request *req;
252 int ret;
253
254 req = peci_request_alloc(device, PECI_GET_TEMP_WR_LEN, PECI_GET_TEMP_RD_LEN);
255 if (!req)
256 return ERR_PTR(-ENOMEM);
257
258 req->tx.buf[0] = PECI_GET_TEMP_CMD;
259
260 ret = peci_request_xfer(req);
261 if (ret) {
262 peci_request_free(req);
263 return ERR_PTR(ret);
264 }
265
266 return req;
267 }
268 EXPORT_SYMBOL_NS_GPL(peci_xfer_get_temp, PECI);
269
270 static struct peci_request *
__pkg_cfg_read(struct peci_device * device,u8 index,u16 param,u8 len)271 __pkg_cfg_read(struct peci_device *device, u8 index, u16 param, u8 len)
272 {
273 struct peci_request *req;
274 int ret;
275
276 req = peci_request_alloc(device, PECI_RDPKGCFG_WR_LEN, PECI_RDPKGCFG_RD_LEN_BASE + len);
277 if (!req)
278 return ERR_PTR(-ENOMEM);
279
280 req->tx.buf[0] = PECI_RDPKGCFG_CMD;
281 req->tx.buf[1] = 0;
282 req->tx.buf[2] = index;
283 put_unaligned_le16(param, &req->tx.buf[3]);
284
285 ret = peci_request_xfer_retry(req);
286 if (ret) {
287 peci_request_free(req);
288 return ERR_PTR(ret);
289 }
290
291 return req;
292 }
293
__get_pci_addr(u8 bus,u8 dev,u8 func,u16 reg)294 static u32 __get_pci_addr(u8 bus, u8 dev, u8 func, u16 reg)
295 {
296 return reg | PCI_DEVID(bus, PCI_DEVFN(dev, func)) << 12;
297 }
298
299 static struct peci_request *
__pci_cfg_local_read(struct peci_device * device,u8 bus,u8 dev,u8 func,u16 reg,u8 len)300 __pci_cfg_local_read(struct peci_device *device, u8 bus, u8 dev, u8 func, u16 reg, u8 len)
301 {
302 struct peci_request *req;
303 u32 pci_addr;
304 int ret;
305
306 req = peci_request_alloc(device, PECI_RDPCICFGLOCAL_WR_LEN,
307 PECI_RDPCICFGLOCAL_RD_LEN_BASE + len);
308 if (!req)
309 return ERR_PTR(-ENOMEM);
310
311 pci_addr = __get_pci_addr(bus, dev, func, reg);
312
313 req->tx.buf[0] = PECI_RDPCICFGLOCAL_CMD;
314 req->tx.buf[1] = 0;
315 put_unaligned_le24(pci_addr, &req->tx.buf[2]);
316
317 ret = peci_request_xfer_retry(req);
318 if (ret) {
319 peci_request_free(req);
320 return ERR_PTR(ret);
321 }
322
323 return req;
324 }
325
326 static struct peci_request *
__ep_pci_cfg_read(struct peci_device * device,u8 msg_type,u8 seg,u8 bus,u8 dev,u8 func,u16 reg,u8 len)327 __ep_pci_cfg_read(struct peci_device *device, u8 msg_type, u8 seg,
328 u8 bus, u8 dev, u8 func, u16 reg, u8 len)
329 {
330 struct peci_request *req;
331 u32 pci_addr;
332 int ret;
333
334 req = peci_request_alloc(device, PECI_RDENDPTCFG_PCI_WR_LEN,
335 PECI_RDENDPTCFG_RD_LEN_BASE + len);
336 if (!req)
337 return ERR_PTR(-ENOMEM);
338
339 pci_addr = __get_pci_addr(bus, dev, func, reg);
340
341 req->tx.buf[0] = PECI_RDENDPTCFG_CMD;
342 req->tx.buf[1] = 0;
343 req->tx.buf[2] = msg_type;
344 req->tx.buf[3] = 0;
345 req->tx.buf[4] = 0;
346 req->tx.buf[5] = 0;
347 req->tx.buf[6] = PECI_ENDPTCFG_ADDR_TYPE_PCI;
348 req->tx.buf[7] = seg; /* PCI Segment */
349 put_unaligned_le32(pci_addr, &req->tx.buf[8]);
350
351 ret = peci_request_xfer_retry(req);
352 if (ret) {
353 peci_request_free(req);
354 return ERR_PTR(ret);
355 }
356
357 return req;
358 }
359
360 static struct peci_request *
__ep_mmio_read(struct peci_device * device,u8 bar,u8 addr_type,u8 seg,u8 bus,u8 dev,u8 func,u64 offset,u8 tx_len,u8 len)361 __ep_mmio_read(struct peci_device *device, u8 bar, u8 addr_type, u8 seg,
362 u8 bus, u8 dev, u8 func, u64 offset, u8 tx_len, u8 len)
363 {
364 struct peci_request *req;
365 int ret;
366
367 req = peci_request_alloc(device, tx_len, PECI_RDENDPTCFG_RD_LEN_BASE + len);
368 if (!req)
369 return ERR_PTR(-ENOMEM);
370
371 req->tx.buf[0] = PECI_RDENDPTCFG_CMD;
372 req->tx.buf[1] = 0;
373 req->tx.buf[2] = PECI_ENDPTCFG_TYPE_MMIO;
374 req->tx.buf[3] = 0; /* Endpoint ID */
375 req->tx.buf[4] = 0; /* Reserved */
376 req->tx.buf[5] = bar;
377 req->tx.buf[6] = addr_type;
378 req->tx.buf[7] = seg; /* PCI Segment */
379 req->tx.buf[8] = PCI_DEVFN(dev, func);
380 req->tx.buf[9] = bus; /* PCI Bus */
381
382 if (addr_type == PECI_ENDPTCFG_ADDR_TYPE_MMIO_D)
383 put_unaligned_le32(offset, &req->tx.buf[10]);
384 else
385 put_unaligned_le64(offset, &req->tx.buf[10]);
386
387 ret = peci_request_xfer_retry(req);
388 if (ret) {
389 peci_request_free(req);
390 return ERR_PTR(ret);
391 }
392
393 return req;
394 }
395
peci_request_data_readb(struct peci_request * req)396 u8 peci_request_data_readb(struct peci_request *req)
397 {
398 return req->rx.buf[1];
399 }
400 EXPORT_SYMBOL_NS_GPL(peci_request_data_readb, PECI);
401
peci_request_data_readw(struct peci_request * req)402 u16 peci_request_data_readw(struct peci_request *req)
403 {
404 return get_unaligned_le16(&req->rx.buf[1]);
405 }
406 EXPORT_SYMBOL_NS_GPL(peci_request_data_readw, PECI);
407
peci_request_data_readl(struct peci_request * req)408 u32 peci_request_data_readl(struct peci_request *req)
409 {
410 return get_unaligned_le32(&req->rx.buf[1]);
411 }
412 EXPORT_SYMBOL_NS_GPL(peci_request_data_readl, PECI);
413
peci_request_data_readq(struct peci_request * req)414 u64 peci_request_data_readq(struct peci_request *req)
415 {
416 return get_unaligned_le64(&req->rx.buf[1]);
417 }
418 EXPORT_SYMBOL_NS_GPL(peci_request_data_readq, PECI);
419
peci_request_dib_read(struct peci_request * req)420 u64 peci_request_dib_read(struct peci_request *req)
421 {
422 return get_unaligned_le64(&req->rx.buf[0]);
423 }
424 EXPORT_SYMBOL_NS_GPL(peci_request_dib_read, PECI);
425
peci_request_temp_read(struct peci_request * req)426 s16 peci_request_temp_read(struct peci_request *req)
427 {
428 return get_unaligned_le16(&req->rx.buf[0]);
429 }
430 EXPORT_SYMBOL_NS_GPL(peci_request_temp_read, PECI);
431
432 #define __read_pkg_config(x, type) \
433 struct peci_request *peci_xfer_pkg_cfg_##x(struct peci_device *device, u8 index, u16 param) \
434 { \
435 return __pkg_cfg_read(device, index, param, sizeof(type)); \
436 } \
437 EXPORT_SYMBOL_NS_GPL(peci_xfer_pkg_cfg_##x, PECI)
438
439 __read_pkg_config(readb, u8);
440 __read_pkg_config(readw, u16);
441 __read_pkg_config(readl, u32);
442 __read_pkg_config(readq, u64);
443
444 #define __read_pci_config_local(x, type) \
445 struct peci_request * \
446 peci_xfer_pci_cfg_local_##x(struct peci_device *device, u8 bus, u8 dev, u8 func, u16 reg) \
447 { \
448 return __pci_cfg_local_read(device, bus, dev, func, reg, sizeof(type)); \
449 } \
450 EXPORT_SYMBOL_NS_GPL(peci_xfer_pci_cfg_local_##x, PECI)
451
452 __read_pci_config_local(readb, u8);
453 __read_pci_config_local(readw, u16);
454 __read_pci_config_local(readl, u32);
455
456 #define __read_ep_pci_config(x, msg_type, type) \
457 struct peci_request * \
458 peci_xfer_ep_pci_cfg_##x(struct peci_device *device, u8 seg, u8 bus, u8 dev, u8 func, u16 reg) \
459 { \
460 return __ep_pci_cfg_read(device, msg_type, seg, bus, dev, func, reg, sizeof(type)); \
461 } \
462 EXPORT_SYMBOL_NS_GPL(peci_xfer_ep_pci_cfg_##x, PECI)
463
464 __read_ep_pci_config(local_readb, PECI_ENDPTCFG_TYPE_LOCAL_PCI, u8);
465 __read_ep_pci_config(local_readw, PECI_ENDPTCFG_TYPE_LOCAL_PCI, u16);
466 __read_ep_pci_config(local_readl, PECI_ENDPTCFG_TYPE_LOCAL_PCI, u32);
467 __read_ep_pci_config(readb, PECI_ENDPTCFG_TYPE_PCI, u8);
468 __read_ep_pci_config(readw, PECI_ENDPTCFG_TYPE_PCI, u16);
469 __read_ep_pci_config(readl, PECI_ENDPTCFG_TYPE_PCI, u32);
470
471 #define __read_ep_mmio(x, y, addr_type, type1, type2) \
472 struct peci_request *peci_xfer_ep_mmio##y##_##x(struct peci_device *device, u8 bar, u8 seg, \
473 u8 bus, u8 dev, u8 func, u64 offset) \
474 { \
475 return __ep_mmio_read(device, bar, addr_type, seg, bus, dev, func, \
476 offset, PECI_RDENDPTCFG_MMIO_WR_LEN_BASE + sizeof(type1), \
477 sizeof(type2)); \
478 } \
479 EXPORT_SYMBOL_NS_GPL(peci_xfer_ep_mmio##y##_##x, PECI)
480
481 __read_ep_mmio(readl, 32, PECI_ENDPTCFG_ADDR_TYPE_MMIO_D, u32, u32);
482 __read_ep_mmio(readl, 64, PECI_ENDPTCFG_ADDR_TYPE_MMIO_Q, u64, u32);
483