1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ISH-TP client driver for ISH firmware loading
4  *
5  * Copyright (c) 2019, Intel Corporation.
6  */
7 
8 #include <linux/firmware.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/intel-ish-client-if.h>
12 #include <linux/property.h>
13 #include <asm/cacheflush.h>
14 
15 /* Number of times we attempt to load the firmware before giving up */
16 #define MAX_LOAD_ATTEMPTS			3
17 
18 /* ISH TX/RX ring buffer pool size */
19 #define LOADER_CL_RX_RING_SIZE			1
20 #define LOADER_CL_TX_RING_SIZE			1
21 
22 /*
23  * ISH Shim firmware loader reserves 4 Kb buffer in SRAM. The buffer is
24  * used to temporarily hold the data transferred from host to Shim
25  * firmware loader. Reason for the odd size of 3968 bytes? Each IPC
26  * transfer is 128 bytes (= 4 bytes header + 124 bytes payload). So the
27  * 4 Kb buffer can hold maximum of 32 IPC transfers, which means we can
28  * have a max payload of 3968 bytes (= 32 x 124 payload).
29  */
30 #define LOADER_SHIM_IPC_BUF_SIZE		3968
31 
32 /**
33  * enum ish_loader_commands -	ISH loader host commands.
34  * LOADER_CMD_XFER_QUERY	Query the Shim firmware loader for
35  *				capabilities
36  * LOADER_CMD_XFER_FRAGMENT	Transfer one firmware image fragment at a
37  *				time. The command may be executed
38  *				multiple times until the entire firmware
39  *				image is downloaded to SRAM.
40  * LOADER_CMD_START		Start executing the main firmware.
41  */
42 enum ish_loader_commands {
43 	LOADER_CMD_XFER_QUERY = 0,
44 	LOADER_CMD_XFER_FRAGMENT,
45 	LOADER_CMD_START,
46 };
47 
48 /* Command bit mask */
49 #define	CMD_MASK				GENMASK(6, 0)
50 #define	IS_RESPONSE				BIT(7)
51 
52 /*
53  * ISH firmware max delay for one transmit failure is 1 Hz,
54  * and firmware will retry 2 times, so 3 Hz is used for timeout.
55  */
56 #define ISHTP_SEND_TIMEOUT			(3 * HZ)
57 
58 /*
59  * Loader transfer modes:
60  *
61  * LOADER_XFER_MODE_ISHTP mode uses the existing ISH-TP mechanism to
62  * transfer data. This may use IPC or DMA if supported in firmware.
63  * The buffer size is limited to 4 Kb by the IPC/ISH-TP protocol for
64  * both IPC & DMA (legacy).
65  *
66  * LOADER_XFER_MODE_DIRECT_DMA - firmware loading is a bit different
67  * from the sensor data streaming. Here we download a large (300+ Kb)
68  * image directly to ISH SRAM memory. There is limited benefit of
69  * DMA'ing 300 Kb image in 4 Kb chucks limit. Hence, we introduce
70  * this "direct dma" mode, where we do not use ISH-TP for DMA, but
71  * instead manage the DMA directly in kernel driver and Shim firmware
72  * loader (allocate buffer, break in chucks and transfer). This allows
73  * to overcome 4 Kb limit, and optimize the data flow path in firmware.
74  */
75 #define LOADER_XFER_MODE_DIRECT_DMA		BIT(0)
76 #define LOADER_XFER_MODE_ISHTP			BIT(1)
77 
78 /* ISH Transport Loader client unique GUID */
79 static const guid_t loader_ishtp_guid =
80 	GUID_INIT(0xc804d06a, 0x55bd, 0x4ea7,
81 		  0xad, 0xed, 0x1e, 0x31, 0x22, 0x8c, 0x76, 0xdc);
82 
83 #define FILENAME_SIZE				256
84 
85 /*
86  * The firmware loading latency will be minimum if we can DMA the
87  * entire ISH firmware image in one go. This requires that we allocate
88  * a large DMA buffer in kernel, which could be problematic on some
89  * platforms. So here we limit the DMA buffer size via a module_param.
90  * We default to 4 pages, but a customer can set it to higher limit if
91  * deemed appropriate for his platform.
92  */
93 static int dma_buf_size_limit = 4 * PAGE_SIZE;
94 
95 /**
96  * struct loader_msg_hdr - Header for ISH Loader commands.
97  * @command:		LOADER_CMD* commands. Bit 7 is the response.
98  * @status:		Command response status. Non 0, is error
99  *			condition.
100  *
101  * This structure is used as header for every command/data sent/received
102  * between Host driver and ISH Shim firmware loader.
103  */
104 struct loader_msg_hdr {
105 	u8 command;
106 	u8 reserved[2];
107 	u8 status;
108 } __packed;
109 
110 struct loader_xfer_query {
111 	struct loader_msg_hdr hdr;
112 	u32 image_size;
113 } __packed;
114 
115 struct ish_fw_version {
116 	u16 major;
117 	u16 minor;
118 	u16 hotfix;
119 	u16 build;
120 } __packed;
121 
122 union loader_version {
123 	u32 value;
124 	struct {
125 		u8 major;
126 		u8 minor;
127 		u8 hotfix;
128 		u8 build;
129 	};
130 } __packed;
131 
132 struct loader_capability {
133 	u32 max_fw_image_size;
134 	u32 xfer_mode;
135 	u32 max_dma_buf_size; /* only for dma mode, multiples of cacheline */
136 } __packed;
137 
138 struct shim_fw_info {
139 	struct ish_fw_version ish_fw_version;
140 	u32 protocol_version;
141 	union loader_version ldr_version;
142 	struct loader_capability ldr_capability;
143 } __packed;
144 
145 struct loader_xfer_query_response {
146 	struct loader_msg_hdr hdr;
147 	struct shim_fw_info fw_info;
148 } __packed;
149 
150 struct loader_xfer_fragment {
151 	struct loader_msg_hdr hdr;
152 	u32 xfer_mode;
153 	u32 offset;
154 	u32 size;
155 	u32 is_last;
156 } __packed;
157 
158 struct loader_xfer_ipc_fragment {
159 	struct loader_xfer_fragment fragment;
160 	u8 data[] ____cacheline_aligned; /* variable length payload here */
161 } __packed;
162 
163 struct loader_xfer_dma_fragment {
164 	struct loader_xfer_fragment fragment;
165 	u64 ddr_phys_addr;
166 } __packed;
167 
168 struct loader_start {
169 	struct loader_msg_hdr hdr;
170 } __packed;
171 
172 /**
173  * struct response_info - Encapsulate firmware response related
174  *			information for passing between function
175  *			loader_cl_send() and process_recv() callback.
176  * @data		Copy the data received from firmware here.
177  * @max_size		Max size allocated for the @data buffer. If the
178  *			received data exceeds this value, we log an
179  *			error.
180  * @size		Actual size of data received from firmware.
181  * @error		Returns 0 for success, negative error code for a
182  *			failure in function process_recv().
183  * @received		Set to true on receiving a valid firmware
184  *			response to host command
185  * @wait_queue		Wait queue for Host firmware loading where the
186  *			client sends message to ISH firmware and waits
187  *			for response
188  */
189 struct response_info {
190 	void *data;
191 	size_t max_size;
192 	size_t size;
193 	int error;
194 	bool received;
195 	wait_queue_head_t wait_queue;
196 };
197 
198 /**
199  * struct ishtp_cl_data - Encapsulate per ISH-TP Client Data.
200  * @work_ishtp_reset:	Work queue for reset handling.
201  * @work_fw_load:	Work queue for host firmware loading.
202  * @flag_retry		Flag for indicating host firmware loading should
203  *			be retried.
204  * @retry_count		Count the number of retries.
205  *
206  * This structure is used to store data per client.
207  */
208 struct ishtp_cl_data {
209 	struct ishtp_cl *loader_ishtp_cl;
210 	struct ishtp_cl_device *cl_device;
211 
212 	/*
213 	 * Used for passing firmware response information between
214 	 * loader_cl_send() and process_recv() callback.
215 	 */
216 	struct response_info response;
217 
218 	struct work_struct work_ishtp_reset;
219 	struct work_struct work_fw_load;
220 
221 	/*
222 	 * In certain failure scenrios, it makes sense to reset the ISH
223 	 * subsystem and retry Host firmware loading (e.g. bad message
224 	 * packet, ENOMEM, etc.). On the other hand, failures due to
225 	 * protocol mismatch, etc., are not recoverable. We do not
226 	 * retry them.
227 	 *
228 	 * If set, the flag indicates that we should re-try the
229 	 * particular failure.
230 	 */
231 	bool flag_retry;
232 	int retry_count;
233 };
234 
235 #define IPC_FRAGMENT_DATA_PREAMBLE				\
236 	offsetof(struct loader_xfer_ipc_fragment, data)
237 
238 #define cl_data_to_dev(client_data) ishtp_device((client_data)->cl_device)
239 
240 /**
241  * get_firmware_variant() - Gets the filename of firmware image to be
242  *			loaded based on platform variant.
243  * @client_data		Client data instance.
244  * @filename		Returns firmware filename.
245  *
246  * Queries the firmware-name device property string.
247  *
248  * Return: 0 for success, negative error code for failure.
249  */
250 static int get_firmware_variant(struct ishtp_cl_data *client_data,
251 				char *filename)
252 {
253 	int rv;
254 	const char *val;
255 	struct device *devc = ishtp_get_pci_device(client_data->cl_device);
256 
257 	rv = device_property_read_string(devc, "firmware-name", &val);
258 	if (rv < 0) {
259 		dev_err(devc,
260 			"Error: ISH firmware-name device property required\n");
261 		return rv;
262 	}
263 	return snprintf(filename, FILENAME_SIZE, "intel/%s", val);
264 }
265 
266 /**
267  * loader_cl_send()	Send message from host to firmware
268  * @client_data:	Client data instance
269  * @out_msg		Message buffer to be sent to firmware
270  * @out_size		Size of out going message
271  * @in_msg		Message buffer where the incoming data copied.
272  *			This buffer is allocated by calling
273  * @in_size		Max size of incoming message
274  *
275  * Return: Number of bytes copied in the in_msg on success, negative
276  * error code on failure.
277  */
278 static int loader_cl_send(struct ishtp_cl_data *client_data,
279 			  u8 *out_msg, size_t out_size,
280 			  u8 *in_msg, size_t in_size)
281 {
282 	int rv;
283 	struct loader_msg_hdr *out_hdr = (struct loader_msg_hdr *)out_msg;
284 	struct ishtp_cl *loader_ishtp_cl = client_data->loader_ishtp_cl;
285 
286 	dev_dbg(cl_data_to_dev(client_data),
287 		"%s: command=%02lx is_response=%u status=%02x\n",
288 		__func__,
289 		out_hdr->command & CMD_MASK,
290 		out_hdr->command & IS_RESPONSE ? 1 : 0,
291 		out_hdr->status);
292 
293 	/* Setup in coming buffer & size */
294 	client_data->response.data = in_msg;
295 	client_data->response.max_size = in_size;
296 	client_data->response.error = 0;
297 	client_data->response.received = false;
298 
299 	rv = ishtp_cl_send(loader_ishtp_cl, out_msg, out_size);
300 	if (rv < 0) {
301 		dev_err(cl_data_to_dev(client_data),
302 			"ishtp_cl_send error %d\n", rv);
303 		return rv;
304 	}
305 
306 	wait_event_interruptible_timeout(client_data->response.wait_queue,
307 					 client_data->response.received,
308 					 ISHTP_SEND_TIMEOUT);
309 	if (!client_data->response.received) {
310 		dev_err(cl_data_to_dev(client_data),
311 			"Timed out for response to command=%02lx",
312 			out_hdr->command & CMD_MASK);
313 		return -ETIMEDOUT;
314 	}
315 
316 	if (client_data->response.error < 0)
317 		return client_data->response.error;
318 
319 	return client_data->response.size;
320 }
321 
322 /**
323  * process_recv() -	Receive and parse incoming packet
324  * @loader_ishtp_cl:	Client instance to get stats
325  * @rb_in_proc:		ISH received message buffer
326  *
327  * Parse the incoming packet. If it is a response packet then it will
328  * update received and wake up the caller waiting to for the response.
329  */
330 static void process_recv(struct ishtp_cl *loader_ishtp_cl,
331 			 struct ishtp_cl_rb *rb_in_proc)
332 {
333 	struct loader_msg_hdr *hdr;
334 	size_t data_len = rb_in_proc->buf_idx;
335 	struct ishtp_cl_data *client_data =
336 		ishtp_get_client_data(loader_ishtp_cl);
337 
338 	/* Sanity check */
339 	if (!client_data->response.data) {
340 		dev_err(cl_data_to_dev(client_data),
341 			"Receiving buffer is null. Should be allocated by calling function\n");
342 		client_data->response.error = -EINVAL;
343 		goto end;
344 	}
345 
346 	if (client_data->response.received) {
347 		dev_err(cl_data_to_dev(client_data),
348 			"Previous firmware message not yet processed\n");
349 		client_data->response.error = -EINVAL;
350 		goto end;
351 	}
352 	/*
353 	 * All firmware messages have a header. Check buffer size
354 	 * before accessing elements inside.
355 	 */
356 	if (!rb_in_proc->buffer.data) {
357 		dev_warn(cl_data_to_dev(client_data),
358 			 "rb_in_proc->buffer.data returned null");
359 		client_data->response.error = -EBADMSG;
360 		goto end;
361 	}
362 
363 	if (data_len < sizeof(struct loader_msg_hdr)) {
364 		dev_err(cl_data_to_dev(client_data),
365 			"data size %zu is less than header %zu\n",
366 			data_len, sizeof(struct loader_msg_hdr));
367 		client_data->response.error = -EMSGSIZE;
368 		goto end;
369 	}
370 
371 	hdr = (struct loader_msg_hdr *)rb_in_proc->buffer.data;
372 
373 	dev_dbg(cl_data_to_dev(client_data),
374 		"%s: command=%02lx is_response=%u status=%02x\n",
375 		__func__,
376 		hdr->command & CMD_MASK,
377 		hdr->command & IS_RESPONSE ? 1 : 0,
378 		hdr->status);
379 
380 	if (((hdr->command & CMD_MASK) != LOADER_CMD_XFER_QUERY) &&
381 	    ((hdr->command & CMD_MASK) != LOADER_CMD_XFER_FRAGMENT) &&
382 	    ((hdr->command & CMD_MASK) != LOADER_CMD_START)) {
383 		dev_err(cl_data_to_dev(client_data),
384 			"Invalid command=%02lx\n",
385 			hdr->command & CMD_MASK);
386 		client_data->response.error = -EPROTO;
387 		goto end;
388 	}
389 
390 	if (data_len > client_data->response.max_size) {
391 		dev_err(cl_data_to_dev(client_data),
392 			"Received buffer size %zu is larger than allocated buffer %zu\n",
393 			data_len, client_data->response.max_size);
394 		client_data->response.error = -EMSGSIZE;
395 		goto end;
396 	}
397 
398 	/* We expect only "response" messages from firmware */
399 	if (!(hdr->command & IS_RESPONSE)) {
400 		dev_err(cl_data_to_dev(client_data),
401 			"Invalid response to command\n");
402 		client_data->response.error = -EIO;
403 		goto end;
404 	}
405 
406 	if (hdr->status) {
407 		dev_err(cl_data_to_dev(client_data),
408 			"Loader returned status %d\n",
409 			hdr->status);
410 		client_data->response.error = -EIO;
411 		goto end;
412 	}
413 
414 	/* Update the actual received buffer size */
415 	client_data->response.size = data_len;
416 
417 	/*
418 	 * Copy the buffer received in firmware response for the
419 	 * calling thread.
420 	 */
421 	memcpy(client_data->response.data,
422 	       rb_in_proc->buffer.data, data_len);
423 
424 	/* Set flag before waking up the caller */
425 	client_data->response.received = true;
426 
427 end:
428 	/* Free the buffer */
429 	ishtp_cl_io_rb_recycle(rb_in_proc);
430 	rb_in_proc = NULL;
431 
432 	/* Wake the calling thread */
433 	wake_up_interruptible(&client_data->response.wait_queue);
434 }
435 
436 /**
437  * loader_cl_event_cb() - bus driver callback for incoming message
438  * @device:		Pointer to the ishtp client device for which this
439  *			message is targeted
440  *
441  * Remove the packet from the list and process the message by calling
442  * process_recv
443  */
444 static void loader_cl_event_cb(struct ishtp_cl_device *cl_device)
445 {
446 	struct ishtp_cl_rb *rb_in_proc;
447 	struct ishtp_cl	*loader_ishtp_cl = ishtp_get_drvdata(cl_device);
448 
449 	while ((rb_in_proc = ishtp_cl_rx_get_rb(loader_ishtp_cl)) != NULL) {
450 		/* Process the data packet from firmware */
451 		process_recv(loader_ishtp_cl, rb_in_proc);
452 	}
453 }
454 
455 /**
456  * ish_query_loader_prop() -  Query ISH Shim firmware loader
457  * @client_data:	Client data instance
458  * @fw:			Poiner to firmware data struct in host memory
459  * @fw_info:		Loader firmware properties
460  *
461  * This function queries the ISH Shim firmware loader for capabilities.
462  *
463  * Return: 0 for success, negative error code for failure.
464  */
465 static int ish_query_loader_prop(struct ishtp_cl_data *client_data,
466 				 const struct firmware *fw,
467 				 struct shim_fw_info *fw_info)
468 {
469 	int rv;
470 	struct loader_xfer_query ldr_xfer_query;
471 	struct loader_xfer_query_response ldr_xfer_query_resp;
472 
473 	memset(&ldr_xfer_query, 0, sizeof(ldr_xfer_query));
474 	ldr_xfer_query.hdr.command = LOADER_CMD_XFER_QUERY;
475 	ldr_xfer_query.image_size = fw->size;
476 	rv = loader_cl_send(client_data,
477 			    (u8 *)&ldr_xfer_query,
478 			    sizeof(ldr_xfer_query),
479 			    (u8 *)&ldr_xfer_query_resp,
480 			    sizeof(ldr_xfer_query_resp));
481 	if (rv < 0) {
482 		client_data->flag_retry = true;
483 		*fw_info = (struct shim_fw_info){};
484 		return rv;
485 	}
486 
487 	/* On success, the return value is the received buffer size */
488 	if (rv != sizeof(struct loader_xfer_query_response)) {
489 		dev_err(cl_data_to_dev(client_data),
490 			"data size %d is not equal to size of loader_xfer_query_response %zu\n",
491 			rv, sizeof(struct loader_xfer_query_response));
492 		client_data->flag_retry = true;
493 		*fw_info = (struct shim_fw_info){};
494 		return -EMSGSIZE;
495 	}
496 
497 	/* Save fw_info for use outside this function */
498 	*fw_info = ldr_xfer_query_resp.fw_info;
499 
500 	/* Loader firmware properties */
501 	dev_dbg(cl_data_to_dev(client_data),
502 		"ish_fw_version: major=%d minor=%d hotfix=%d build=%d protocol_version=0x%x loader_version=%d\n",
503 		fw_info->ish_fw_version.major,
504 		fw_info->ish_fw_version.minor,
505 		fw_info->ish_fw_version.hotfix,
506 		fw_info->ish_fw_version.build,
507 		fw_info->protocol_version,
508 		fw_info->ldr_version.value);
509 
510 	dev_dbg(cl_data_to_dev(client_data),
511 		"loader_capability: max_fw_image_size=0x%x xfer_mode=%d max_dma_buf_size=0x%x dma_buf_size_limit=0x%x\n",
512 		fw_info->ldr_capability.max_fw_image_size,
513 		fw_info->ldr_capability.xfer_mode,
514 		fw_info->ldr_capability.max_dma_buf_size,
515 		dma_buf_size_limit);
516 
517 	/* Sanity checks */
518 	if (fw_info->ldr_capability.max_fw_image_size < fw->size) {
519 		dev_err(cl_data_to_dev(client_data),
520 			"ISH firmware size %zu is greater than Shim firmware loader max supported %d\n",
521 			fw->size,
522 			fw_info->ldr_capability.max_fw_image_size);
523 		return -ENOSPC;
524 	}
525 
526 	/* For DMA the buffer size should be multiple of cacheline size */
527 	if ((fw_info->ldr_capability.xfer_mode & LOADER_XFER_MODE_DIRECT_DMA) &&
528 	    (fw_info->ldr_capability.max_dma_buf_size % L1_CACHE_BYTES)) {
529 		dev_err(cl_data_to_dev(client_data),
530 			"Shim firmware loader buffer size %d should be multiple of cacheline\n",
531 			fw_info->ldr_capability.max_dma_buf_size);
532 		return -EINVAL;
533 	}
534 
535 	return 0;
536 }
537 
538 /**
539  * ish_fw_xfer_ishtp()	Loads ISH firmware using ishtp interface
540  * @client_data:	Client data instance
541  * @fw:			Pointer to firmware data struct in host memory
542  *
543  * This function uses ISH-TP to transfer ISH firmware from host to
544  * ISH SRAM. Lower layers may use IPC or DMA depending on firmware
545  * support.
546  *
547  * Return: 0 for success, negative error code for failure.
548  */
549 static int ish_fw_xfer_ishtp(struct ishtp_cl_data *client_data,
550 			     const struct firmware *fw)
551 {
552 	int rv;
553 	u32 fragment_offset, fragment_size, payload_max_size;
554 	struct loader_xfer_ipc_fragment *ldr_xfer_ipc_frag;
555 	struct loader_msg_hdr ldr_xfer_ipc_ack;
556 
557 	payload_max_size =
558 		LOADER_SHIM_IPC_BUF_SIZE - IPC_FRAGMENT_DATA_PREAMBLE;
559 
560 	ldr_xfer_ipc_frag = kzalloc(LOADER_SHIM_IPC_BUF_SIZE, GFP_KERNEL);
561 	if (!ldr_xfer_ipc_frag) {
562 		client_data->flag_retry = true;
563 		return -ENOMEM;
564 	}
565 
566 	ldr_xfer_ipc_frag->fragment.hdr.command = LOADER_CMD_XFER_FRAGMENT;
567 	ldr_xfer_ipc_frag->fragment.xfer_mode = LOADER_XFER_MODE_ISHTP;
568 
569 	/* Break the firmware image into fragments and send as ISH-TP payload */
570 	fragment_offset = 0;
571 	while (fragment_offset < fw->size) {
572 		if (fragment_offset + payload_max_size < fw->size) {
573 			fragment_size = payload_max_size;
574 			ldr_xfer_ipc_frag->fragment.is_last = 0;
575 		} else {
576 			fragment_size = fw->size - fragment_offset;
577 			ldr_xfer_ipc_frag->fragment.is_last = 1;
578 		}
579 
580 		ldr_xfer_ipc_frag->fragment.offset = fragment_offset;
581 		ldr_xfer_ipc_frag->fragment.size = fragment_size;
582 		memcpy(ldr_xfer_ipc_frag->data,
583 		       &fw->data[fragment_offset],
584 		       fragment_size);
585 
586 		dev_dbg(cl_data_to_dev(client_data),
587 			"xfer_mode=ipc offset=0x%08x size=0x%08x is_last=%d\n",
588 			ldr_xfer_ipc_frag->fragment.offset,
589 			ldr_xfer_ipc_frag->fragment.size,
590 			ldr_xfer_ipc_frag->fragment.is_last);
591 
592 		rv = loader_cl_send(client_data,
593 				    (u8 *)ldr_xfer_ipc_frag,
594 				    IPC_FRAGMENT_DATA_PREAMBLE + fragment_size,
595 				    (u8 *)&ldr_xfer_ipc_ack,
596 				    sizeof(ldr_xfer_ipc_ack));
597 		if (rv < 0) {
598 			client_data->flag_retry = true;
599 			goto end_err_resp_buf_release;
600 		}
601 
602 		fragment_offset += fragment_size;
603 	}
604 
605 	kfree(ldr_xfer_ipc_frag);
606 	return 0;
607 
608 end_err_resp_buf_release:
609 	/* Free ISH buffer if not done already, in error case */
610 	kfree(ldr_xfer_ipc_frag);
611 	return rv;
612 }
613 
614 /**
615  * ish_fw_xfer_direct_dma() - Loads ISH firmware using direct dma
616  * @client_data:	Client data instance
617  * @fw:			Pointer to firmware data struct in host memory
618  * @fw_info:		Loader firmware properties
619  *
620  * Host firmware load is a unique case where we need to download
621  * a large firmware image (200+ Kb). This function implements
622  * direct DMA transfer in kernel and ISH firmware. This allows
623  * us to overcome the ISH-TP 4 Kb limit, and allows us to DMA
624  * directly to ISH UMA at location of choice.
625  * Function depends on corresponding support in ISH firmware.
626  *
627  * Return: 0 for success, negative error code for failure.
628  */
629 static int ish_fw_xfer_direct_dma(struct ishtp_cl_data *client_data,
630 				  const struct firmware *fw,
631 				  const struct shim_fw_info fw_info)
632 {
633 	int rv;
634 	void *dma_buf;
635 	dma_addr_t dma_buf_phy;
636 	u32 fragment_offset, fragment_size, payload_max_size;
637 	struct loader_msg_hdr ldr_xfer_dma_frag_ack;
638 	struct loader_xfer_dma_fragment ldr_xfer_dma_frag;
639 	struct device *devc = ishtp_get_pci_device(client_data->cl_device);
640 	u32 shim_fw_buf_size =
641 		fw_info.ldr_capability.max_dma_buf_size;
642 
643 	/*
644 	 * payload_max_size should be set to minimum of
645 	 *  (1) Size of firmware to be loaded,
646 	 *  (2) Max DMA buffer size supported by Shim firmware,
647 	 *  (3) DMA buffer size limit set by boot_param dma_buf_size_limit.
648 	 */
649 	payload_max_size = min3(fw->size,
650 				(size_t)shim_fw_buf_size,
651 				(size_t)dma_buf_size_limit);
652 
653 	/*
654 	 * Buffer size should be multiple of cacheline size
655 	 * if it's not, select the previous cacheline boundary.
656 	 */
657 	payload_max_size &= ~(L1_CACHE_BYTES - 1);
658 
659 	dma_buf = kmalloc(payload_max_size, GFP_KERNEL | GFP_DMA32);
660 	if (!dma_buf) {
661 		client_data->flag_retry = true;
662 		return -ENOMEM;
663 	}
664 
665 	dma_buf_phy = dma_map_single(devc, dma_buf, payload_max_size,
666 				     DMA_TO_DEVICE);
667 	if (dma_mapping_error(devc, dma_buf_phy)) {
668 		dev_err(cl_data_to_dev(client_data), "DMA map failed\n");
669 		client_data->flag_retry = true;
670 		rv = -ENOMEM;
671 		goto end_err_dma_buf_release;
672 	}
673 
674 	ldr_xfer_dma_frag.fragment.hdr.command = LOADER_CMD_XFER_FRAGMENT;
675 	ldr_xfer_dma_frag.fragment.xfer_mode = LOADER_XFER_MODE_DIRECT_DMA;
676 	ldr_xfer_dma_frag.ddr_phys_addr = (u64)dma_buf_phy;
677 
678 	/* Send the firmware image in chucks of payload_max_size */
679 	fragment_offset = 0;
680 	while (fragment_offset < fw->size) {
681 		if (fragment_offset + payload_max_size < fw->size) {
682 			fragment_size = payload_max_size;
683 			ldr_xfer_dma_frag.fragment.is_last = 0;
684 		} else {
685 			fragment_size = fw->size - fragment_offset;
686 			ldr_xfer_dma_frag.fragment.is_last = 1;
687 		}
688 
689 		ldr_xfer_dma_frag.fragment.offset = fragment_offset;
690 		ldr_xfer_dma_frag.fragment.size = fragment_size;
691 		memcpy(dma_buf, &fw->data[fragment_offset], fragment_size);
692 
693 		dma_sync_single_for_device(devc, dma_buf_phy,
694 					   payload_max_size,
695 					   DMA_TO_DEVICE);
696 
697 		/*
698 		 * Flush cache here because the dma_sync_single_for_device()
699 		 * does not do for x86.
700 		 */
701 		clflush_cache_range(dma_buf, payload_max_size);
702 
703 		dev_dbg(cl_data_to_dev(client_data),
704 			"xfer_mode=dma offset=0x%08x size=0x%x is_last=%d ddr_phys_addr=0x%016llx\n",
705 			ldr_xfer_dma_frag.fragment.offset,
706 			ldr_xfer_dma_frag.fragment.size,
707 			ldr_xfer_dma_frag.fragment.is_last,
708 			ldr_xfer_dma_frag.ddr_phys_addr);
709 
710 		rv = loader_cl_send(client_data,
711 				    (u8 *)&ldr_xfer_dma_frag,
712 				    sizeof(ldr_xfer_dma_frag),
713 				    (u8 *)&ldr_xfer_dma_frag_ack,
714 				    sizeof(ldr_xfer_dma_frag_ack));
715 		if (rv < 0) {
716 			client_data->flag_retry = true;
717 			goto end_err_resp_buf_release;
718 		}
719 
720 		fragment_offset += fragment_size;
721 	}
722 
723 	dma_unmap_single(devc, dma_buf_phy, payload_max_size, DMA_TO_DEVICE);
724 	kfree(dma_buf);
725 	return 0;
726 
727 end_err_resp_buf_release:
728 	/* Free ISH buffer if not done already, in error case */
729 	dma_unmap_single(devc, dma_buf_phy, payload_max_size, DMA_TO_DEVICE);
730 end_err_dma_buf_release:
731 	kfree(dma_buf);
732 	return rv;
733 }
734 
735 /**
736  * ish_fw_start()	Start executing ISH main firmware
737  * @client_data:	client data instance
738  *
739  * This function sends message to Shim firmware loader to start
740  * the execution of ISH main firmware.
741  *
742  * Return: 0 for success, negative error code for failure.
743  */
744 static int ish_fw_start(struct ishtp_cl_data *client_data)
745 {
746 	struct loader_start ldr_start;
747 	struct loader_msg_hdr ldr_start_ack;
748 
749 	memset(&ldr_start, 0, sizeof(ldr_start));
750 	ldr_start.hdr.command = LOADER_CMD_START;
751 	return loader_cl_send(client_data,
752 			    (u8 *)&ldr_start,
753 			    sizeof(ldr_start),
754 			    (u8 *)&ldr_start_ack,
755 			    sizeof(ldr_start_ack));
756 }
757 
758 /**
759  * load_fw_from_host()	Loads ISH firmware from host
760  * @client_data:	Client data instance
761  *
762  * This function loads the ISH firmware to ISH SRAM and starts execution
763  *
764  * Return: 0 for success, negative error code for failure.
765  */
766 static int load_fw_from_host(struct ishtp_cl_data *client_data)
767 {
768 	int rv;
769 	u32 xfer_mode;
770 	char *filename;
771 	const struct firmware *fw;
772 	struct shim_fw_info fw_info;
773 	struct ishtp_cl *loader_ishtp_cl = client_data->loader_ishtp_cl;
774 
775 	client_data->flag_retry = false;
776 
777 	filename = kzalloc(FILENAME_SIZE, GFP_KERNEL);
778 	if (!filename) {
779 		client_data->flag_retry = true;
780 		rv = -ENOMEM;
781 		goto end_error;
782 	}
783 
784 	/* Get filename of the ISH firmware to be loaded */
785 	rv = get_firmware_variant(client_data, filename);
786 	if (rv < 0)
787 		goto end_err_filename_buf_release;
788 
789 	rv = request_firmware(&fw, filename, cl_data_to_dev(client_data));
790 	if (rv < 0)
791 		goto end_err_filename_buf_release;
792 
793 	/* Step 1: Query Shim firmware loader properties */
794 
795 	rv = ish_query_loader_prop(client_data, fw, &fw_info);
796 	if (rv < 0)
797 		goto end_err_fw_release;
798 
799 	/* Step 2: Send the main firmware image to be loaded, to ISH SRAM */
800 
801 	xfer_mode = fw_info.ldr_capability.xfer_mode;
802 	if (xfer_mode & LOADER_XFER_MODE_DIRECT_DMA) {
803 		rv = ish_fw_xfer_direct_dma(client_data, fw, fw_info);
804 	} else if (xfer_mode & LOADER_XFER_MODE_ISHTP) {
805 		rv = ish_fw_xfer_ishtp(client_data, fw);
806 	} else {
807 		dev_err(cl_data_to_dev(client_data),
808 			"No transfer mode selected in firmware\n");
809 		rv = -EINVAL;
810 	}
811 	if (rv < 0)
812 		goto end_err_fw_release;
813 
814 	/* Step 3: Start ISH main firmware exeuction */
815 
816 	rv = ish_fw_start(client_data);
817 	if (rv < 0)
818 		goto end_err_fw_release;
819 
820 	release_firmware(fw);
821 	dev_info(cl_data_to_dev(client_data), "ISH firmware %s loaded\n",
822 		 filename);
823 	kfree(filename);
824 	return 0;
825 
826 end_err_fw_release:
827 	release_firmware(fw);
828 end_err_filename_buf_release:
829 	kfree(filename);
830 end_error:
831 	/* Keep a count of retries, and give up after 3 attempts */
832 	if (client_data->flag_retry &&
833 	    client_data->retry_count++ < MAX_LOAD_ATTEMPTS) {
834 		dev_warn(cl_data_to_dev(client_data),
835 			 "ISH host firmware load failed %d. Resetting ISH, and trying again..\n",
836 			 rv);
837 		ish_hw_reset(ishtp_get_ishtp_device(loader_ishtp_cl));
838 	} else {
839 		dev_err(cl_data_to_dev(client_data),
840 			"ISH host firmware load failed %d\n", rv);
841 	}
842 	return rv;
843 }
844 
845 static void load_fw_from_host_handler(struct work_struct *work)
846 {
847 	struct ishtp_cl_data *client_data;
848 
849 	client_data = container_of(work, struct ishtp_cl_data,
850 				   work_fw_load);
851 	load_fw_from_host(client_data);
852 }
853 
854 /**
855  * loader_init() -	Init function for ISH-TP client
856  * @loader_ishtp_cl:	ISH-TP client instance
857  * @reset:		true if called for init after reset
858  *
859  * Return: 0 for success, negative error code for failure
860  */
861 static int loader_init(struct ishtp_cl *loader_ishtp_cl, int reset)
862 {
863 	int rv;
864 	struct ishtp_fw_client *fw_client;
865 	struct ishtp_cl_data *client_data =
866 		ishtp_get_client_data(loader_ishtp_cl);
867 
868 	dev_dbg(cl_data_to_dev(client_data), "reset flag: %d\n", reset);
869 
870 	rv = ishtp_cl_link(loader_ishtp_cl);
871 	if (rv < 0) {
872 		dev_err(cl_data_to_dev(client_data), "ishtp_cl_link failed\n");
873 		return rv;
874 	}
875 
876 	/* Connect to firmware client */
877 	ishtp_set_tx_ring_size(loader_ishtp_cl, LOADER_CL_TX_RING_SIZE);
878 	ishtp_set_rx_ring_size(loader_ishtp_cl, LOADER_CL_RX_RING_SIZE);
879 
880 	fw_client =
881 		ishtp_fw_cl_get_client(ishtp_get_ishtp_device(loader_ishtp_cl),
882 				       &loader_ishtp_guid);
883 	if (!fw_client) {
884 		dev_err(cl_data_to_dev(client_data),
885 			"ISH client uuid not found\n");
886 		rv = -ENOENT;
887 		goto err_cl_unlink;
888 	}
889 
890 	ishtp_cl_set_fw_client_id(loader_ishtp_cl,
891 				  ishtp_get_fw_client_id(fw_client));
892 	ishtp_set_connection_state(loader_ishtp_cl, ISHTP_CL_CONNECTING);
893 
894 	rv = ishtp_cl_connect(loader_ishtp_cl);
895 	if (rv < 0) {
896 		dev_err(cl_data_to_dev(client_data), "Client connect fail\n");
897 		goto err_cl_unlink;
898 	}
899 
900 	dev_dbg(cl_data_to_dev(client_data), "Client connected\n");
901 
902 	ishtp_register_event_cb(client_data->cl_device, loader_cl_event_cb);
903 
904 	return 0;
905 
906 err_cl_unlink:
907 	ishtp_cl_unlink(loader_ishtp_cl);
908 	return rv;
909 }
910 
911 static void loader_deinit(struct ishtp_cl *loader_ishtp_cl)
912 {
913 	ishtp_set_connection_state(loader_ishtp_cl, ISHTP_CL_DISCONNECTING);
914 	ishtp_cl_disconnect(loader_ishtp_cl);
915 	ishtp_cl_unlink(loader_ishtp_cl);
916 	ishtp_cl_flush_queues(loader_ishtp_cl);
917 
918 	/* Disband and free all Tx and Rx client-level rings */
919 	ishtp_cl_free(loader_ishtp_cl);
920 }
921 
922 static void reset_handler(struct work_struct *work)
923 {
924 	int rv;
925 	struct ishtp_cl_data *client_data;
926 	struct ishtp_cl *loader_ishtp_cl;
927 	struct ishtp_cl_device *cl_device;
928 
929 	client_data = container_of(work, struct ishtp_cl_data,
930 				   work_ishtp_reset);
931 
932 	loader_ishtp_cl = client_data->loader_ishtp_cl;
933 	cl_device = client_data->cl_device;
934 
935 	/* Unlink, flush queues & start again */
936 	ishtp_cl_unlink(loader_ishtp_cl);
937 	ishtp_cl_flush_queues(loader_ishtp_cl);
938 	ishtp_cl_free(loader_ishtp_cl);
939 
940 	loader_ishtp_cl = ishtp_cl_allocate(cl_device);
941 	if (!loader_ishtp_cl)
942 		return;
943 
944 	ishtp_set_drvdata(cl_device, loader_ishtp_cl);
945 	ishtp_set_client_data(loader_ishtp_cl, client_data);
946 	client_data->loader_ishtp_cl = loader_ishtp_cl;
947 	client_data->cl_device = cl_device;
948 
949 	rv = loader_init(loader_ishtp_cl, 1);
950 	if (rv < 0) {
951 		dev_err(ishtp_device(cl_device), "Reset Failed\n");
952 		return;
953 	}
954 
955 	/* ISH firmware loading from host */
956 	load_fw_from_host(client_data);
957 }
958 
959 /**
960  * loader_ishtp_cl_probe() - ISH-TP client driver probe
961  * @cl_device:		ISH-TP client device instance
962  *
963  * This function gets called on device create on ISH-TP bus
964  *
965  * Return: 0 for success, negative error code for failure
966  */
967 static int loader_ishtp_cl_probe(struct ishtp_cl_device *cl_device)
968 {
969 	struct ishtp_cl *loader_ishtp_cl;
970 	struct ishtp_cl_data *client_data;
971 	int rv;
972 
973 	client_data = devm_kzalloc(ishtp_device(cl_device),
974 				   sizeof(*client_data),
975 				   GFP_KERNEL);
976 	if (!client_data)
977 		return -ENOMEM;
978 
979 	loader_ishtp_cl = ishtp_cl_allocate(cl_device);
980 	if (!loader_ishtp_cl)
981 		return -ENOMEM;
982 
983 	ishtp_set_drvdata(cl_device, loader_ishtp_cl);
984 	ishtp_set_client_data(loader_ishtp_cl, client_data);
985 	client_data->loader_ishtp_cl = loader_ishtp_cl;
986 	client_data->cl_device = cl_device;
987 
988 	init_waitqueue_head(&client_data->response.wait_queue);
989 
990 	INIT_WORK(&client_data->work_ishtp_reset,
991 		  reset_handler);
992 	INIT_WORK(&client_data->work_fw_load,
993 		  load_fw_from_host_handler);
994 
995 	rv = loader_init(loader_ishtp_cl, 0);
996 	if (rv < 0) {
997 		ishtp_cl_free(loader_ishtp_cl);
998 		return rv;
999 	}
1000 	ishtp_get_device(cl_device);
1001 
1002 	client_data->retry_count = 0;
1003 
1004 	/* ISH firmware loading from host */
1005 	schedule_work(&client_data->work_fw_load);
1006 
1007 	return 0;
1008 }
1009 
1010 /**
1011  * loader_ishtp_cl_remove() - ISH-TP client driver remove
1012  * @cl_device:		ISH-TP client device instance
1013  *
1014  * This function gets called on device remove on ISH-TP bus
1015  *
1016  * Return: 0
1017  */
1018 static int loader_ishtp_cl_remove(struct ishtp_cl_device *cl_device)
1019 {
1020 	struct ishtp_cl_data *client_data;
1021 	struct ishtp_cl	*loader_ishtp_cl = ishtp_get_drvdata(cl_device);
1022 
1023 	client_data = ishtp_get_client_data(loader_ishtp_cl);
1024 
1025 	/*
1026 	 * The sequence of the following two cancel_work_sync() is
1027 	 * important. The work_fw_load can in turn schedue
1028 	 * work_ishtp_reset, so first cancel work_fw_load then
1029 	 * cancel work_ishtp_reset.
1030 	 */
1031 	cancel_work_sync(&client_data->work_fw_load);
1032 	cancel_work_sync(&client_data->work_ishtp_reset);
1033 	loader_deinit(loader_ishtp_cl);
1034 	ishtp_put_device(cl_device);
1035 
1036 	return 0;
1037 }
1038 
1039 /**
1040  * loader_ishtp_cl_reset() - ISH-TP client driver reset
1041  * @cl_device:		ISH-TP client device instance
1042  *
1043  * This function gets called on device reset on ISH-TP bus
1044  *
1045  * Return: 0
1046  */
1047 static int loader_ishtp_cl_reset(struct ishtp_cl_device *cl_device)
1048 {
1049 	struct ishtp_cl_data *client_data;
1050 	struct ishtp_cl	*loader_ishtp_cl = ishtp_get_drvdata(cl_device);
1051 
1052 	client_data = ishtp_get_client_data(loader_ishtp_cl);
1053 
1054 	schedule_work(&client_data->work_ishtp_reset);
1055 
1056 	return 0;
1057 }
1058 
1059 static struct ishtp_cl_driver	loader_ishtp_cl_driver = {
1060 	.name = "ish-loader",
1061 	.guid = &loader_ishtp_guid,
1062 	.probe = loader_ishtp_cl_probe,
1063 	.remove = loader_ishtp_cl_remove,
1064 	.reset = loader_ishtp_cl_reset,
1065 };
1066 
1067 static int __init ish_loader_init(void)
1068 {
1069 	return ishtp_cl_driver_register(&loader_ishtp_cl_driver, THIS_MODULE);
1070 }
1071 
1072 static void __exit ish_loader_exit(void)
1073 {
1074 	ishtp_cl_driver_unregister(&loader_ishtp_cl_driver);
1075 }
1076 
1077 late_initcall(ish_loader_init);
1078 module_exit(ish_loader_exit);
1079 
1080 module_param(dma_buf_size_limit, int, 0644);
1081 MODULE_PARM_DESC(dma_buf_size_limit, "Limit the DMA buf size to this value in bytes");
1082 
1083 MODULE_DESCRIPTION("ISH ISH-TP Host firmware Loader Client Driver");
1084 MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@intel.com>");
1085 
1086 MODULE_LICENSE("GPL v2");
1087 MODULE_ALIAS("ishtp:*");
1088