1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
4  *
5  */
6 
7 #include <linux/debugfs.h>
8 #include <linux/device.h>
9 #include <linux/dma-direction.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/idr.h>
12 #include <linux/interrupt.h>
13 #include <linux/list.h>
14 #include <linux/mhi.h>
15 #include <linux/mod_devicetable.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
19 #include <linux/wait.h>
20 #include "internal.h"
21 
22 static DEFINE_IDA(mhi_controller_ida);
23 
24 const char * const mhi_ee_str[MHI_EE_MAX] = {
25 	[MHI_EE_PBL] = "PRIMARY BOOTLOADER",
26 	[MHI_EE_SBL] = "SECONDARY BOOTLOADER",
27 	[MHI_EE_AMSS] = "MISSION MODE",
28 	[MHI_EE_RDDM] = "RAMDUMP DOWNLOAD MODE",
29 	[MHI_EE_WFW] = "WLAN FIRMWARE",
30 	[MHI_EE_PTHRU] = "PASS THROUGH",
31 	[MHI_EE_EDL] = "EMERGENCY DOWNLOAD",
32 	[MHI_EE_FP] = "FLASH PROGRAMMER",
33 	[MHI_EE_DISABLE_TRANSITION] = "DISABLE",
34 	[MHI_EE_NOT_SUPPORTED] = "NOT SUPPORTED",
35 };
36 
37 const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
38 	[DEV_ST_TRANSITION_PBL] = "PBL",
39 	[DEV_ST_TRANSITION_READY] = "READY",
40 	[DEV_ST_TRANSITION_SBL] = "SBL",
41 	[DEV_ST_TRANSITION_MISSION_MODE] = "MISSION MODE",
42 	[DEV_ST_TRANSITION_FP] = "FLASH PROGRAMMER",
43 	[DEV_ST_TRANSITION_SYS_ERR] = "SYS ERROR",
44 	[DEV_ST_TRANSITION_DISABLE] = "DISABLE",
45 };
46 
47 const char * const mhi_state_str[MHI_STATE_MAX] = {
48 	[MHI_STATE_RESET] = "RESET",
49 	[MHI_STATE_READY] = "READY",
50 	[MHI_STATE_M0] = "M0",
51 	[MHI_STATE_M1] = "M1",
52 	[MHI_STATE_M2] = "M2",
53 	[MHI_STATE_M3] = "M3",
54 	[MHI_STATE_M3_FAST] = "M3 FAST",
55 	[MHI_STATE_BHI] = "BHI",
56 	[MHI_STATE_SYS_ERR] = "SYS ERROR",
57 };
58 
59 const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX] = {
60 	[MHI_CH_STATE_TYPE_RESET] = "RESET",
61 	[MHI_CH_STATE_TYPE_STOP] = "STOP",
62 	[MHI_CH_STATE_TYPE_START] = "START",
63 };
64 
65 static const char * const mhi_pm_state_str[] = {
66 	[MHI_PM_STATE_DISABLE] = "DISABLE",
67 	[MHI_PM_STATE_POR] = "POWER ON RESET",
68 	[MHI_PM_STATE_M0] = "M0",
69 	[MHI_PM_STATE_M2] = "M2",
70 	[MHI_PM_STATE_M3_ENTER] = "M?->M3",
71 	[MHI_PM_STATE_M3] = "M3",
72 	[MHI_PM_STATE_M3_EXIT] = "M3->M0",
73 	[MHI_PM_STATE_FW_DL_ERR] = "Firmware Download Error",
74 	[MHI_PM_STATE_SYS_ERR_DETECT] = "SYS ERROR Detect",
75 	[MHI_PM_STATE_SYS_ERR_PROCESS] = "SYS ERROR Process",
76 	[MHI_PM_STATE_SHUTDOWN_PROCESS] = "SHUTDOWN Process",
77 	[MHI_PM_STATE_LD_ERR_FATAL_DETECT] = "Linkdown or Error Fatal Detect",
78 };
79 
to_mhi_pm_state_str(enum mhi_pm_state state)80 const char *to_mhi_pm_state_str(enum mhi_pm_state state)
81 {
82 	int index = find_last_bit((unsigned long *)&state, 32);
83 
84 	if (index >= ARRAY_SIZE(mhi_pm_state_str))
85 		return "Invalid State";
86 
87 	return mhi_pm_state_str[index];
88 }
89 
serial_number_show(struct device * dev,struct device_attribute * attr,char * buf)90 static ssize_t serial_number_show(struct device *dev,
91 				  struct device_attribute *attr,
92 				  char *buf)
93 {
94 	struct mhi_device *mhi_dev = to_mhi_device(dev);
95 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
96 
97 	return snprintf(buf, PAGE_SIZE, "Serial Number: %u\n",
98 			mhi_cntrl->serial_number);
99 }
100 static DEVICE_ATTR_RO(serial_number);
101 
oem_pk_hash_show(struct device * dev,struct device_attribute * attr,char * buf)102 static ssize_t oem_pk_hash_show(struct device *dev,
103 				struct device_attribute *attr,
104 				char *buf)
105 {
106 	struct mhi_device *mhi_dev = to_mhi_device(dev);
107 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
108 	int i, cnt = 0;
109 
110 	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++)
111 		cnt += snprintf(buf + cnt, PAGE_SIZE - cnt,
112 				"OEMPKHASH[%d]: 0x%x\n", i,
113 				mhi_cntrl->oem_pk_hash[i]);
114 
115 	return cnt;
116 }
117 static DEVICE_ATTR_RO(oem_pk_hash);
118 
119 static struct attribute *mhi_dev_attrs[] = {
120 	&dev_attr_serial_number.attr,
121 	&dev_attr_oem_pk_hash.attr,
122 	NULL,
123 };
124 ATTRIBUTE_GROUPS(mhi_dev);
125 
126 /* MHI protocol requires the transfer ring to be aligned with ring length */
mhi_alloc_aligned_ring(struct mhi_controller * mhi_cntrl,struct mhi_ring * ring,u64 len)127 static int mhi_alloc_aligned_ring(struct mhi_controller *mhi_cntrl,
128 				  struct mhi_ring *ring,
129 				  u64 len)
130 {
131 	ring->alloc_size = len + (len - 1);
132 	ring->pre_aligned = dma_alloc_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
133 					       &ring->dma_handle, GFP_KERNEL);
134 	if (!ring->pre_aligned)
135 		return -ENOMEM;
136 
137 	ring->iommu_base = (ring->dma_handle + (len - 1)) & ~(len - 1);
138 	ring->base = ring->pre_aligned + (ring->iommu_base - ring->dma_handle);
139 
140 	return 0;
141 }
142 
mhi_deinit_free_irq(struct mhi_controller * mhi_cntrl)143 void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl)
144 {
145 	int i;
146 	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
147 
148 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
149 		if (mhi_event->offload_ev)
150 			continue;
151 
152 		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
153 	}
154 
155 	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
156 }
157 
mhi_init_irq_setup(struct mhi_controller * mhi_cntrl)158 int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl)
159 {
160 	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
161 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
162 	unsigned long irq_flags = IRQF_SHARED | IRQF_NO_SUSPEND;
163 	int i, ret;
164 
165 	/* if controller driver has set irq_flags, use it */
166 	if (mhi_cntrl->irq_flags)
167 		irq_flags = mhi_cntrl->irq_flags;
168 
169 	/* Setup BHI_INTVEC IRQ */
170 	ret = request_threaded_irq(mhi_cntrl->irq[0], mhi_intvec_handler,
171 				   mhi_intvec_threaded_handler,
172 				   irq_flags,
173 				   "bhi", mhi_cntrl);
174 	if (ret)
175 		return ret;
176 
177 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
178 		if (mhi_event->offload_ev)
179 			continue;
180 
181 		if (mhi_event->irq >= mhi_cntrl->nr_irqs) {
182 			dev_err(dev, "irq %d not available for event ring\n",
183 				mhi_event->irq);
184 			ret = -EINVAL;
185 			goto error_request;
186 		}
187 
188 		ret = request_irq(mhi_cntrl->irq[mhi_event->irq],
189 				  mhi_irq_handler,
190 				  irq_flags,
191 				  "mhi", mhi_event);
192 		if (ret) {
193 			dev_err(dev, "Error requesting irq:%d for ev:%d\n",
194 				mhi_cntrl->irq[mhi_event->irq], i);
195 			goto error_request;
196 		}
197 	}
198 
199 	return 0;
200 
201 error_request:
202 	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
203 		if (mhi_event->offload_ev)
204 			continue;
205 
206 		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
207 	}
208 	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
209 
210 	return ret;
211 }
212 
mhi_deinit_dev_ctxt(struct mhi_controller * mhi_cntrl)213 void mhi_deinit_dev_ctxt(struct mhi_controller *mhi_cntrl)
214 {
215 	int i;
216 	struct mhi_ctxt *mhi_ctxt = mhi_cntrl->mhi_ctxt;
217 	struct mhi_cmd *mhi_cmd;
218 	struct mhi_event *mhi_event;
219 	struct mhi_ring *ring;
220 
221 	mhi_cmd = mhi_cntrl->mhi_cmd;
222 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++) {
223 		ring = &mhi_cmd->ring;
224 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
225 				  ring->pre_aligned, ring->dma_handle);
226 		ring->base = NULL;
227 		ring->iommu_base = 0;
228 	}
229 
230 	dma_free_coherent(mhi_cntrl->cntrl_dev,
231 			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
232 			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
233 
234 	mhi_event = mhi_cntrl->mhi_event;
235 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
236 		if (mhi_event->offload_ev)
237 			continue;
238 
239 		ring = &mhi_event->ring;
240 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
241 				  ring->pre_aligned, ring->dma_handle);
242 		ring->base = NULL;
243 		ring->iommu_base = 0;
244 	}
245 
246 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
247 			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
248 			  mhi_ctxt->er_ctxt_addr);
249 
250 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
251 			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
252 			  mhi_ctxt->chan_ctxt_addr);
253 
254 	kfree(mhi_ctxt);
255 	mhi_cntrl->mhi_ctxt = NULL;
256 }
257 
mhi_init_dev_ctxt(struct mhi_controller * mhi_cntrl)258 int mhi_init_dev_ctxt(struct mhi_controller *mhi_cntrl)
259 {
260 	struct mhi_ctxt *mhi_ctxt;
261 	struct mhi_chan_ctxt *chan_ctxt;
262 	struct mhi_event_ctxt *er_ctxt;
263 	struct mhi_cmd_ctxt *cmd_ctxt;
264 	struct mhi_chan *mhi_chan;
265 	struct mhi_event *mhi_event;
266 	struct mhi_cmd *mhi_cmd;
267 	u32 tmp;
268 	int ret = -ENOMEM, i;
269 
270 	atomic_set(&mhi_cntrl->dev_wake, 0);
271 	atomic_set(&mhi_cntrl->pending_pkts, 0);
272 
273 	mhi_ctxt = kzalloc(sizeof(*mhi_ctxt), GFP_KERNEL);
274 	if (!mhi_ctxt)
275 		return -ENOMEM;
276 
277 	/* Setup channel ctxt */
278 	mhi_ctxt->chan_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
279 						 sizeof(*mhi_ctxt->chan_ctxt) *
280 						 mhi_cntrl->max_chan,
281 						 &mhi_ctxt->chan_ctxt_addr,
282 						 GFP_KERNEL);
283 	if (!mhi_ctxt->chan_ctxt)
284 		goto error_alloc_chan_ctxt;
285 
286 	mhi_chan = mhi_cntrl->mhi_chan;
287 	chan_ctxt = mhi_ctxt->chan_ctxt;
288 	for (i = 0; i < mhi_cntrl->max_chan; i++, chan_ctxt++, mhi_chan++) {
289 		/* Skip if it is an offload channel */
290 		if (mhi_chan->offload_ch)
291 			continue;
292 
293 		tmp = chan_ctxt->chcfg;
294 		tmp &= ~CHAN_CTX_CHSTATE_MASK;
295 		tmp |= (MHI_CH_STATE_DISABLED << CHAN_CTX_CHSTATE_SHIFT);
296 		tmp &= ~CHAN_CTX_BRSTMODE_MASK;
297 		tmp |= (mhi_chan->db_cfg.brstmode << CHAN_CTX_BRSTMODE_SHIFT);
298 		tmp &= ~CHAN_CTX_POLLCFG_MASK;
299 		tmp |= (mhi_chan->db_cfg.pollcfg << CHAN_CTX_POLLCFG_SHIFT);
300 		chan_ctxt->chcfg = tmp;
301 
302 		chan_ctxt->chtype = mhi_chan->type;
303 		chan_ctxt->erindex = mhi_chan->er_index;
304 
305 		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
306 		mhi_chan->tre_ring.db_addr = (void __iomem *)&chan_ctxt->wp;
307 	}
308 
309 	/* Setup event context */
310 	mhi_ctxt->er_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
311 					       sizeof(*mhi_ctxt->er_ctxt) *
312 					       mhi_cntrl->total_ev_rings,
313 					       &mhi_ctxt->er_ctxt_addr,
314 					       GFP_KERNEL);
315 	if (!mhi_ctxt->er_ctxt)
316 		goto error_alloc_er_ctxt;
317 
318 	er_ctxt = mhi_ctxt->er_ctxt;
319 	mhi_event = mhi_cntrl->mhi_event;
320 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
321 		     mhi_event++) {
322 		struct mhi_ring *ring = &mhi_event->ring;
323 
324 		/* Skip if it is an offload event */
325 		if (mhi_event->offload_ev)
326 			continue;
327 
328 		tmp = er_ctxt->intmod;
329 		tmp &= ~EV_CTX_INTMODC_MASK;
330 		tmp &= ~EV_CTX_INTMODT_MASK;
331 		tmp |= (mhi_event->intmod << EV_CTX_INTMODT_SHIFT);
332 		er_ctxt->intmod = tmp;
333 
334 		er_ctxt->ertype = MHI_ER_TYPE_VALID;
335 		er_ctxt->msivec = mhi_event->irq;
336 		mhi_event->db_cfg.db_mode = true;
337 
338 		ring->el_size = sizeof(struct mhi_tre);
339 		ring->len = ring->el_size * ring->elements;
340 		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
341 		if (ret)
342 			goto error_alloc_er;
343 
344 		/*
345 		 * If the read pointer equals to the write pointer, then the
346 		 * ring is empty
347 		 */
348 		ring->rp = ring->wp = ring->base;
349 		er_ctxt->rbase = ring->iommu_base;
350 		er_ctxt->rp = er_ctxt->wp = er_ctxt->rbase;
351 		er_ctxt->rlen = ring->len;
352 		ring->ctxt_wp = &er_ctxt->wp;
353 	}
354 
355 	/* Setup cmd context */
356 	ret = -ENOMEM;
357 	mhi_ctxt->cmd_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
358 						sizeof(*mhi_ctxt->cmd_ctxt) *
359 						NR_OF_CMD_RINGS,
360 						&mhi_ctxt->cmd_ctxt_addr,
361 						GFP_KERNEL);
362 	if (!mhi_ctxt->cmd_ctxt)
363 		goto error_alloc_er;
364 
365 	mhi_cmd = mhi_cntrl->mhi_cmd;
366 	cmd_ctxt = mhi_ctxt->cmd_ctxt;
367 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
368 		struct mhi_ring *ring = &mhi_cmd->ring;
369 
370 		ring->el_size = sizeof(struct mhi_tre);
371 		ring->elements = CMD_EL_PER_RING;
372 		ring->len = ring->el_size * ring->elements;
373 		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
374 		if (ret)
375 			goto error_alloc_cmd;
376 
377 		ring->rp = ring->wp = ring->base;
378 		cmd_ctxt->rbase = ring->iommu_base;
379 		cmd_ctxt->rp = cmd_ctxt->wp = cmd_ctxt->rbase;
380 		cmd_ctxt->rlen = ring->len;
381 		ring->ctxt_wp = &cmd_ctxt->wp;
382 	}
383 
384 	mhi_cntrl->mhi_ctxt = mhi_ctxt;
385 
386 	return 0;
387 
388 error_alloc_cmd:
389 	for (--i, --mhi_cmd; i >= 0; i--, mhi_cmd--) {
390 		struct mhi_ring *ring = &mhi_cmd->ring;
391 
392 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
393 				  ring->pre_aligned, ring->dma_handle);
394 	}
395 	dma_free_coherent(mhi_cntrl->cntrl_dev,
396 			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
397 			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
398 	i = mhi_cntrl->total_ev_rings;
399 	mhi_event = mhi_cntrl->mhi_event + i;
400 
401 error_alloc_er:
402 	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
403 		struct mhi_ring *ring = &mhi_event->ring;
404 
405 		if (mhi_event->offload_ev)
406 			continue;
407 
408 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
409 				  ring->pre_aligned, ring->dma_handle);
410 	}
411 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
412 			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
413 			  mhi_ctxt->er_ctxt_addr);
414 
415 error_alloc_er_ctxt:
416 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
417 			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
418 			  mhi_ctxt->chan_ctxt_addr);
419 
420 error_alloc_chan_ctxt:
421 	kfree(mhi_ctxt);
422 
423 	return ret;
424 }
425 
mhi_init_mmio(struct mhi_controller * mhi_cntrl)426 int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
427 {
428 	u32 val;
429 	int i, ret;
430 	struct mhi_chan *mhi_chan;
431 	struct mhi_event *mhi_event;
432 	void __iomem *base = mhi_cntrl->regs;
433 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
434 	struct {
435 		u32 offset;
436 		u32 mask;
437 		u32 shift;
438 		u32 val;
439 	} reg_info[] = {
440 		{
441 			CCABAP_HIGHER, U32_MAX, 0,
442 			upper_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
443 		},
444 		{
445 			CCABAP_LOWER, U32_MAX, 0,
446 			lower_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
447 		},
448 		{
449 			ECABAP_HIGHER, U32_MAX, 0,
450 			upper_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
451 		},
452 		{
453 			ECABAP_LOWER, U32_MAX, 0,
454 			lower_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
455 		},
456 		{
457 			CRCBAP_HIGHER, U32_MAX, 0,
458 			upper_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
459 		},
460 		{
461 			CRCBAP_LOWER, U32_MAX, 0,
462 			lower_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
463 		},
464 		{
465 			MHICFG, MHICFG_NER_MASK, MHICFG_NER_SHIFT,
466 			mhi_cntrl->total_ev_rings,
467 		},
468 		{
469 			MHICFG, MHICFG_NHWER_MASK, MHICFG_NHWER_SHIFT,
470 			mhi_cntrl->hw_ev_rings,
471 		},
472 		{
473 			MHICTRLBASE_HIGHER, U32_MAX, 0,
474 			upper_32_bits(mhi_cntrl->iova_start),
475 		},
476 		{
477 			MHICTRLBASE_LOWER, U32_MAX, 0,
478 			lower_32_bits(mhi_cntrl->iova_start),
479 		},
480 		{
481 			MHIDATABASE_HIGHER, U32_MAX, 0,
482 			upper_32_bits(mhi_cntrl->iova_start),
483 		},
484 		{
485 			MHIDATABASE_LOWER, U32_MAX, 0,
486 			lower_32_bits(mhi_cntrl->iova_start),
487 		},
488 		{
489 			MHICTRLLIMIT_HIGHER, U32_MAX, 0,
490 			upper_32_bits(mhi_cntrl->iova_stop),
491 		},
492 		{
493 			MHICTRLLIMIT_LOWER, U32_MAX, 0,
494 			lower_32_bits(mhi_cntrl->iova_stop),
495 		},
496 		{
497 			MHIDATALIMIT_HIGHER, U32_MAX, 0,
498 			upper_32_bits(mhi_cntrl->iova_stop),
499 		},
500 		{
501 			MHIDATALIMIT_LOWER, U32_MAX, 0,
502 			lower_32_bits(mhi_cntrl->iova_stop),
503 		},
504 		{ 0, 0, 0 }
505 	};
506 
507 	dev_dbg(dev, "Initializing MHI registers\n");
508 
509 	/* Read channel db offset */
510 	ret = mhi_read_reg_field(mhi_cntrl, base, CHDBOFF, CHDBOFF_CHDBOFF_MASK,
511 				 CHDBOFF_CHDBOFF_SHIFT, &val);
512 	if (ret) {
513 		dev_err(dev, "Unable to read CHDBOFF register\n");
514 		return -EIO;
515 	}
516 
517 	/* Setup wake db */
518 	mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
519 	mhi_cntrl->wake_set = false;
520 
521 	/* Setup channel db address for each channel in tre_ring */
522 	mhi_chan = mhi_cntrl->mhi_chan;
523 	for (i = 0; i < mhi_cntrl->max_chan; i++, val += 8, mhi_chan++)
524 		mhi_chan->tre_ring.db_addr = base + val;
525 
526 	/* Read event ring db offset */
527 	ret = mhi_read_reg_field(mhi_cntrl, base, ERDBOFF, ERDBOFF_ERDBOFF_MASK,
528 				 ERDBOFF_ERDBOFF_SHIFT, &val);
529 	if (ret) {
530 		dev_err(dev, "Unable to read ERDBOFF register\n");
531 		return -EIO;
532 	}
533 
534 	/* Setup event db address for each ev_ring */
535 	mhi_event = mhi_cntrl->mhi_event;
536 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
537 		if (mhi_event->offload_ev)
538 			continue;
539 
540 		mhi_event->ring.db_addr = base + val;
541 	}
542 
543 	/* Setup DB register for primary CMD rings */
544 	mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING].ring.db_addr = base + CRDB_LOWER;
545 
546 	/* Write to MMIO registers */
547 	for (i = 0; reg_info[i].offset; i++)
548 		mhi_write_reg_field(mhi_cntrl, base, reg_info[i].offset,
549 				    reg_info[i].mask, reg_info[i].shift,
550 				    reg_info[i].val);
551 
552 	return 0;
553 }
554 
mhi_deinit_chan_ctxt(struct mhi_controller * mhi_cntrl,struct mhi_chan * mhi_chan)555 void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
556 			  struct mhi_chan *mhi_chan)
557 {
558 	struct mhi_ring *buf_ring;
559 	struct mhi_ring *tre_ring;
560 	struct mhi_chan_ctxt *chan_ctxt;
561 	u32 tmp;
562 
563 	buf_ring = &mhi_chan->buf_ring;
564 	tre_ring = &mhi_chan->tre_ring;
565 	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
566 
567 	if (!chan_ctxt->rbase) /* Already uninitialized */
568 		return;
569 
570 	dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
571 			  tre_ring->pre_aligned, tre_ring->dma_handle);
572 	vfree(buf_ring->base);
573 
574 	buf_ring->base = tre_ring->base = NULL;
575 	tre_ring->ctxt_wp = NULL;
576 	chan_ctxt->rbase = 0;
577 	chan_ctxt->rlen = 0;
578 	chan_ctxt->rp = 0;
579 	chan_ctxt->wp = 0;
580 
581 	tmp = chan_ctxt->chcfg;
582 	tmp &= ~CHAN_CTX_CHSTATE_MASK;
583 	tmp |= (MHI_CH_STATE_DISABLED << CHAN_CTX_CHSTATE_SHIFT);
584 	chan_ctxt->chcfg = tmp;
585 
586 	/* Update to all cores */
587 	smp_wmb();
588 }
589 
mhi_init_chan_ctxt(struct mhi_controller * mhi_cntrl,struct mhi_chan * mhi_chan)590 int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
591 		       struct mhi_chan *mhi_chan)
592 {
593 	struct mhi_ring *buf_ring;
594 	struct mhi_ring *tre_ring;
595 	struct mhi_chan_ctxt *chan_ctxt;
596 	u32 tmp;
597 	int ret;
598 
599 	buf_ring = &mhi_chan->buf_ring;
600 	tre_ring = &mhi_chan->tre_ring;
601 	tre_ring->el_size = sizeof(struct mhi_tre);
602 	tre_ring->len = tre_ring->el_size * tre_ring->elements;
603 	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
604 	ret = mhi_alloc_aligned_ring(mhi_cntrl, tre_ring, tre_ring->len);
605 	if (ret)
606 		return -ENOMEM;
607 
608 	buf_ring->el_size = sizeof(struct mhi_buf_info);
609 	buf_ring->len = buf_ring->el_size * buf_ring->elements;
610 	buf_ring->base = vzalloc(buf_ring->len);
611 
612 	if (!buf_ring->base) {
613 		dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
614 				  tre_ring->pre_aligned, tre_ring->dma_handle);
615 		return -ENOMEM;
616 	}
617 
618 	tmp = chan_ctxt->chcfg;
619 	tmp &= ~CHAN_CTX_CHSTATE_MASK;
620 	tmp |= (MHI_CH_STATE_ENABLED << CHAN_CTX_CHSTATE_SHIFT);
621 	chan_ctxt->chcfg = tmp;
622 
623 	chan_ctxt->rbase = tre_ring->iommu_base;
624 	chan_ctxt->rp = chan_ctxt->wp = chan_ctxt->rbase;
625 	chan_ctxt->rlen = tre_ring->len;
626 	tre_ring->ctxt_wp = &chan_ctxt->wp;
627 
628 	tre_ring->rp = tre_ring->wp = tre_ring->base;
629 	buf_ring->rp = buf_ring->wp = buf_ring->base;
630 	mhi_chan->db_cfg.db_mode = 1;
631 
632 	/* Update to all cores */
633 	smp_wmb();
634 
635 	return 0;
636 }
637 
parse_ev_cfg(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)638 static int parse_ev_cfg(struct mhi_controller *mhi_cntrl,
639 			const struct mhi_controller_config *config)
640 {
641 	struct mhi_event *mhi_event;
642 	const struct mhi_event_config *event_cfg;
643 	struct device *dev = mhi_cntrl->cntrl_dev;
644 	int i, num;
645 
646 	num = config->num_events;
647 	mhi_cntrl->total_ev_rings = num;
648 	mhi_cntrl->mhi_event = kcalloc(num, sizeof(*mhi_cntrl->mhi_event),
649 				       GFP_KERNEL);
650 	if (!mhi_cntrl->mhi_event)
651 		return -ENOMEM;
652 
653 	/* Populate event ring */
654 	mhi_event = mhi_cntrl->mhi_event;
655 	for (i = 0; i < num; i++) {
656 		event_cfg = &config->event_cfg[i];
657 
658 		mhi_event->er_index = i;
659 		mhi_event->ring.elements = event_cfg->num_elements;
660 		mhi_event->intmod = event_cfg->irq_moderation_ms;
661 		mhi_event->irq = event_cfg->irq;
662 
663 		if (event_cfg->channel != U32_MAX) {
664 			/* This event ring has a dedicated channel */
665 			mhi_event->chan = event_cfg->channel;
666 			if (mhi_event->chan >= mhi_cntrl->max_chan) {
667 				dev_err(dev,
668 					"Event Ring channel not available\n");
669 				goto error_ev_cfg;
670 			}
671 
672 			mhi_event->mhi_chan =
673 				&mhi_cntrl->mhi_chan[mhi_event->chan];
674 		}
675 
676 		/* Priority is fixed to 1 for now */
677 		mhi_event->priority = 1;
678 
679 		mhi_event->db_cfg.brstmode = event_cfg->mode;
680 		if (MHI_INVALID_BRSTMODE(mhi_event->db_cfg.brstmode))
681 			goto error_ev_cfg;
682 
683 		if (mhi_event->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
684 			mhi_event->db_cfg.process_db = mhi_db_brstmode;
685 		else
686 			mhi_event->db_cfg.process_db = mhi_db_brstmode_disable;
687 
688 		mhi_event->data_type = event_cfg->data_type;
689 
690 		switch (mhi_event->data_type) {
691 		case MHI_ER_DATA:
692 			mhi_event->process_event = mhi_process_data_event_ring;
693 			break;
694 		case MHI_ER_CTRL:
695 			mhi_event->process_event = mhi_process_ctrl_ev_ring;
696 			break;
697 		default:
698 			dev_err(dev, "Event Ring type not supported\n");
699 			goto error_ev_cfg;
700 		}
701 
702 		mhi_event->hw_ring = event_cfg->hardware_event;
703 		if (mhi_event->hw_ring)
704 			mhi_cntrl->hw_ev_rings++;
705 		else
706 			mhi_cntrl->sw_ev_rings++;
707 
708 		mhi_event->cl_manage = event_cfg->client_managed;
709 		mhi_event->offload_ev = event_cfg->offload_channel;
710 		mhi_event++;
711 	}
712 
713 	return 0;
714 
715 error_ev_cfg:
716 
717 	kfree(mhi_cntrl->mhi_event);
718 	return -EINVAL;
719 }
720 
parse_ch_cfg(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)721 static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
722 			const struct mhi_controller_config *config)
723 {
724 	const struct mhi_channel_config *ch_cfg;
725 	struct device *dev = mhi_cntrl->cntrl_dev;
726 	int i;
727 	u32 chan;
728 
729 	mhi_cntrl->max_chan = config->max_channels;
730 
731 	/*
732 	 * The allocation of MHI channels can exceed 32KB in some scenarios,
733 	 * so to avoid any memory possible allocation failures, vzalloc is
734 	 * used here
735 	 */
736 	mhi_cntrl->mhi_chan = vzalloc(mhi_cntrl->max_chan *
737 				      sizeof(*mhi_cntrl->mhi_chan));
738 	if (!mhi_cntrl->mhi_chan)
739 		return -ENOMEM;
740 
741 	INIT_LIST_HEAD(&mhi_cntrl->lpm_chans);
742 
743 	/* Populate channel configurations */
744 	for (i = 0; i < config->num_channels; i++) {
745 		struct mhi_chan *mhi_chan;
746 
747 		ch_cfg = &config->ch_cfg[i];
748 
749 		chan = ch_cfg->num;
750 		if (chan >= mhi_cntrl->max_chan) {
751 			dev_err(dev, "Channel %d not available\n", chan);
752 			goto error_chan_cfg;
753 		}
754 
755 		mhi_chan = &mhi_cntrl->mhi_chan[chan];
756 		mhi_chan->name = ch_cfg->name;
757 		mhi_chan->chan = chan;
758 
759 		mhi_chan->tre_ring.elements = ch_cfg->num_elements;
760 		if (!mhi_chan->tre_ring.elements)
761 			goto error_chan_cfg;
762 
763 		/*
764 		 * For some channels, local ring length should be bigger than
765 		 * the transfer ring length due to internal logical channels
766 		 * in device. So host can queue much more buffers than transfer
767 		 * ring length. Example, RSC channels should have a larger local
768 		 * channel length than transfer ring length.
769 		 */
770 		mhi_chan->buf_ring.elements = ch_cfg->local_elements;
771 		if (!mhi_chan->buf_ring.elements)
772 			mhi_chan->buf_ring.elements = mhi_chan->tre_ring.elements;
773 		mhi_chan->er_index = ch_cfg->event_ring;
774 		mhi_chan->dir = ch_cfg->dir;
775 
776 		/*
777 		 * For most channels, chtype is identical to channel directions.
778 		 * So, if it is not defined then assign channel direction to
779 		 * chtype
780 		 */
781 		mhi_chan->type = ch_cfg->type;
782 		if (!mhi_chan->type)
783 			mhi_chan->type = (enum mhi_ch_type)mhi_chan->dir;
784 
785 		mhi_chan->ee_mask = ch_cfg->ee_mask;
786 		mhi_chan->db_cfg.pollcfg = ch_cfg->pollcfg;
787 		mhi_chan->lpm_notify = ch_cfg->lpm_notify;
788 		mhi_chan->offload_ch = ch_cfg->offload_channel;
789 		mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
790 		mhi_chan->pre_alloc = ch_cfg->auto_queue;
791 
792 		/*
793 		 * If MHI host allocates buffers, then the channel direction
794 		 * should be DMA_FROM_DEVICE
795 		 */
796 		if (mhi_chan->pre_alloc && mhi_chan->dir != DMA_FROM_DEVICE) {
797 			dev_err(dev, "Invalid channel configuration\n");
798 			goto error_chan_cfg;
799 		}
800 
801 		/*
802 		 * Bi-directional and direction less channel must be an
803 		 * offload channel
804 		 */
805 		if ((mhi_chan->dir == DMA_BIDIRECTIONAL ||
806 		     mhi_chan->dir == DMA_NONE) && !mhi_chan->offload_ch) {
807 			dev_err(dev, "Invalid channel configuration\n");
808 			goto error_chan_cfg;
809 		}
810 
811 		if (!mhi_chan->offload_ch) {
812 			mhi_chan->db_cfg.brstmode = ch_cfg->doorbell;
813 			if (MHI_INVALID_BRSTMODE(mhi_chan->db_cfg.brstmode)) {
814 				dev_err(dev, "Invalid Door bell mode\n");
815 				goto error_chan_cfg;
816 			}
817 		}
818 
819 		if (mhi_chan->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
820 			mhi_chan->db_cfg.process_db = mhi_db_brstmode;
821 		else
822 			mhi_chan->db_cfg.process_db = mhi_db_brstmode_disable;
823 
824 		mhi_chan->configured = true;
825 
826 		if (mhi_chan->lpm_notify)
827 			list_add_tail(&mhi_chan->node, &mhi_cntrl->lpm_chans);
828 	}
829 
830 	return 0;
831 
832 error_chan_cfg:
833 	vfree(mhi_cntrl->mhi_chan);
834 
835 	return -EINVAL;
836 }
837 
parse_config(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)838 static int parse_config(struct mhi_controller *mhi_cntrl,
839 			const struct mhi_controller_config *config)
840 {
841 	int ret;
842 
843 	/* Parse MHI channel configuration */
844 	ret = parse_ch_cfg(mhi_cntrl, config);
845 	if (ret)
846 		return ret;
847 
848 	/* Parse MHI event configuration */
849 	ret = parse_ev_cfg(mhi_cntrl, config);
850 	if (ret)
851 		goto error_ev_cfg;
852 
853 	mhi_cntrl->timeout_ms = config->timeout_ms;
854 	if (!mhi_cntrl->timeout_ms)
855 		mhi_cntrl->timeout_ms = MHI_TIMEOUT_MS;
856 
857 	mhi_cntrl->bounce_buf = config->use_bounce_buf;
858 	mhi_cntrl->buffer_len = config->buf_len;
859 	if (!mhi_cntrl->buffer_len)
860 		mhi_cntrl->buffer_len = MHI_MAX_MTU;
861 
862 	/* By default, host is allowed to ring DB in both M0 and M2 states */
863 	mhi_cntrl->db_access = MHI_PM_M0 | MHI_PM_M2;
864 	if (config->m2_no_db)
865 		mhi_cntrl->db_access &= ~MHI_PM_M2;
866 
867 	return 0;
868 
869 error_ev_cfg:
870 	vfree(mhi_cntrl->mhi_chan);
871 
872 	return ret;
873 }
874 
mhi_register_controller(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)875 int mhi_register_controller(struct mhi_controller *mhi_cntrl,
876 			    const struct mhi_controller_config *config)
877 {
878 	struct mhi_event *mhi_event;
879 	struct mhi_chan *mhi_chan;
880 	struct mhi_cmd *mhi_cmd;
881 	struct mhi_device *mhi_dev;
882 	u32 soc_info;
883 	int ret, i;
884 
885 	if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->regs ||
886 	    !mhi_cntrl->runtime_get || !mhi_cntrl->runtime_put ||
887 	    !mhi_cntrl->status_cb || !mhi_cntrl->read_reg ||
888 	    !mhi_cntrl->write_reg || !mhi_cntrl->nr_irqs ||
889 	    !mhi_cntrl->irq || !mhi_cntrl->reg_len)
890 		return -EINVAL;
891 
892 	ret = parse_config(mhi_cntrl, config);
893 	if (ret)
894 		return -EINVAL;
895 
896 	mhi_cntrl->mhi_cmd = kcalloc(NR_OF_CMD_RINGS,
897 				     sizeof(*mhi_cntrl->mhi_cmd), GFP_KERNEL);
898 	if (!mhi_cntrl->mhi_cmd) {
899 		ret = -ENOMEM;
900 		goto err_free_event;
901 	}
902 
903 	INIT_LIST_HEAD(&mhi_cntrl->transition_list);
904 	mutex_init(&mhi_cntrl->pm_mutex);
905 	rwlock_init(&mhi_cntrl->pm_lock);
906 	spin_lock_init(&mhi_cntrl->transition_lock);
907 	spin_lock_init(&mhi_cntrl->wlock);
908 	INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
909 	init_waitqueue_head(&mhi_cntrl->state_event);
910 
911 	mhi_cntrl->hiprio_wq = alloc_ordered_workqueue("mhi_hiprio_wq", WQ_HIGHPRI);
912 	if (!mhi_cntrl->hiprio_wq) {
913 		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate workqueue\n");
914 		ret = -ENOMEM;
915 		goto err_free_cmd;
916 	}
917 
918 	mhi_cmd = mhi_cntrl->mhi_cmd;
919 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++)
920 		spin_lock_init(&mhi_cmd->lock);
921 
922 	mhi_event = mhi_cntrl->mhi_event;
923 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
924 		/* Skip for offload events */
925 		if (mhi_event->offload_ev)
926 			continue;
927 
928 		mhi_event->mhi_cntrl = mhi_cntrl;
929 		spin_lock_init(&mhi_event->lock);
930 		if (mhi_event->data_type == MHI_ER_CTRL)
931 			tasklet_init(&mhi_event->task, mhi_ctrl_ev_task,
932 				     (ulong)mhi_event);
933 		else
934 			tasklet_init(&mhi_event->task, mhi_ev_task,
935 				     (ulong)mhi_event);
936 	}
937 
938 	mhi_chan = mhi_cntrl->mhi_chan;
939 	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
940 		mutex_init(&mhi_chan->mutex);
941 		init_completion(&mhi_chan->completion);
942 		rwlock_init(&mhi_chan->lock);
943 
944 		/* used in setting bei field of TRE */
945 		mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index];
946 		mhi_chan->intmod = mhi_event->intmod;
947 	}
948 
949 	if (mhi_cntrl->bounce_buf) {
950 		mhi_cntrl->map_single = mhi_map_single_use_bb;
951 		mhi_cntrl->unmap_single = mhi_unmap_single_use_bb;
952 	} else {
953 		mhi_cntrl->map_single = mhi_map_single_no_bb;
954 		mhi_cntrl->unmap_single = mhi_unmap_single_no_bb;
955 	}
956 
957 	/* Read the MHI device info */
958 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs,
959 			   SOC_HW_VERSION_OFFS, &soc_info);
960 	if (ret)
961 		goto err_destroy_wq;
962 
963 	mhi_cntrl->family_number = (soc_info & SOC_HW_VERSION_FAM_NUM_BMSK) >>
964 					SOC_HW_VERSION_FAM_NUM_SHFT;
965 	mhi_cntrl->device_number = (soc_info & SOC_HW_VERSION_DEV_NUM_BMSK) >>
966 					SOC_HW_VERSION_DEV_NUM_SHFT;
967 	mhi_cntrl->major_version = (soc_info & SOC_HW_VERSION_MAJOR_VER_BMSK) >>
968 					SOC_HW_VERSION_MAJOR_VER_SHFT;
969 	mhi_cntrl->minor_version = (soc_info & SOC_HW_VERSION_MINOR_VER_BMSK) >>
970 					SOC_HW_VERSION_MINOR_VER_SHFT;
971 
972 	mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL);
973 	if (mhi_cntrl->index < 0) {
974 		ret = mhi_cntrl->index;
975 		goto err_destroy_wq;
976 	}
977 
978 	/* Register controller with MHI bus */
979 	mhi_dev = mhi_alloc_device(mhi_cntrl);
980 	if (IS_ERR(mhi_dev)) {
981 		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate MHI device\n");
982 		ret = PTR_ERR(mhi_dev);
983 		goto err_ida_free;
984 	}
985 
986 	mhi_dev->dev_type = MHI_DEVICE_CONTROLLER;
987 	mhi_dev->mhi_cntrl = mhi_cntrl;
988 	dev_set_name(&mhi_dev->dev, "mhi%d", mhi_cntrl->index);
989 	mhi_dev->name = dev_name(&mhi_dev->dev);
990 
991 	/* Init wakeup source */
992 	device_init_wakeup(&mhi_dev->dev, true);
993 
994 	ret = device_add(&mhi_dev->dev);
995 	if (ret)
996 		goto err_release_dev;
997 
998 	mhi_cntrl->mhi_dev = mhi_dev;
999 
1000 	mhi_create_debugfs(mhi_cntrl);
1001 
1002 	return 0;
1003 
1004 err_release_dev:
1005 	put_device(&mhi_dev->dev);
1006 err_ida_free:
1007 	ida_free(&mhi_controller_ida, mhi_cntrl->index);
1008 err_destroy_wq:
1009 	destroy_workqueue(mhi_cntrl->hiprio_wq);
1010 err_free_cmd:
1011 	kfree(mhi_cntrl->mhi_cmd);
1012 err_free_event:
1013 	kfree(mhi_cntrl->mhi_event);
1014 	vfree(mhi_cntrl->mhi_chan);
1015 
1016 	return ret;
1017 }
1018 EXPORT_SYMBOL_GPL(mhi_register_controller);
1019 
mhi_unregister_controller(struct mhi_controller * mhi_cntrl)1020 void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
1021 {
1022 	struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
1023 	struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan;
1024 	unsigned int i;
1025 
1026 	mhi_destroy_debugfs(mhi_cntrl);
1027 
1028 	destroy_workqueue(mhi_cntrl->hiprio_wq);
1029 	kfree(mhi_cntrl->mhi_cmd);
1030 	kfree(mhi_cntrl->mhi_event);
1031 
1032 	/* Drop the references to MHI devices created for channels */
1033 	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
1034 		if (!mhi_chan->mhi_dev)
1035 			continue;
1036 
1037 		put_device(&mhi_chan->mhi_dev->dev);
1038 	}
1039 	vfree(mhi_cntrl->mhi_chan);
1040 
1041 	device_del(&mhi_dev->dev);
1042 	put_device(&mhi_dev->dev);
1043 
1044 	ida_free(&mhi_controller_ida, mhi_cntrl->index);
1045 }
1046 EXPORT_SYMBOL_GPL(mhi_unregister_controller);
1047 
mhi_alloc_controller(void)1048 struct mhi_controller *mhi_alloc_controller(void)
1049 {
1050 	struct mhi_controller *mhi_cntrl;
1051 
1052 	mhi_cntrl = kzalloc(sizeof(*mhi_cntrl), GFP_KERNEL);
1053 
1054 	return mhi_cntrl;
1055 }
1056 EXPORT_SYMBOL_GPL(mhi_alloc_controller);
1057 
mhi_free_controller(struct mhi_controller * mhi_cntrl)1058 void mhi_free_controller(struct mhi_controller *mhi_cntrl)
1059 {
1060 	kfree(mhi_cntrl);
1061 }
1062 EXPORT_SYMBOL_GPL(mhi_free_controller);
1063 
mhi_prepare_for_power_up(struct mhi_controller * mhi_cntrl)1064 int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
1065 {
1066 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
1067 	u32 bhi_off, bhie_off;
1068 	int ret;
1069 
1070 	mutex_lock(&mhi_cntrl->pm_mutex);
1071 
1072 	ret = mhi_init_dev_ctxt(mhi_cntrl);
1073 	if (ret)
1074 		goto error_dev_ctxt;
1075 
1076 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIOFF, &bhi_off);
1077 	if (ret) {
1078 		dev_err(dev, "Error getting BHI offset\n");
1079 		goto error_reg_offset;
1080 	}
1081 
1082 	if (bhi_off >= mhi_cntrl->reg_len) {
1083 		dev_err(dev, "BHI offset: 0x%x is out of range: 0x%zx\n",
1084 			bhi_off, mhi_cntrl->reg_len);
1085 		ret = -EINVAL;
1086 		goto error_reg_offset;
1087 	}
1088 	mhi_cntrl->bhi = mhi_cntrl->regs + bhi_off;
1089 
1090 	if (mhi_cntrl->fbc_download || mhi_cntrl->rddm_size) {
1091 		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIEOFF,
1092 				   &bhie_off);
1093 		if (ret) {
1094 			dev_err(dev, "Error getting BHIE offset\n");
1095 			goto error_reg_offset;
1096 		}
1097 
1098 		if (bhie_off >= mhi_cntrl->reg_len) {
1099 			dev_err(dev,
1100 				"BHIe offset: 0x%x is out of range: 0x%zx\n",
1101 				bhie_off, mhi_cntrl->reg_len);
1102 			ret = -EINVAL;
1103 			goto error_reg_offset;
1104 		}
1105 		mhi_cntrl->bhie = mhi_cntrl->regs + bhie_off;
1106 	}
1107 
1108 	if (mhi_cntrl->rddm_size) {
1109 		/*
1110 		 * This controller supports RDDM, so we need to manually clear
1111 		 * BHIE RX registers since POR values are undefined.
1112 		 */
1113 		memset_io(mhi_cntrl->bhie + BHIE_RXVECADDR_LOW_OFFS,
1114 			  0, BHIE_RXVECSTATUS_OFFS - BHIE_RXVECADDR_LOW_OFFS +
1115 			  4);
1116 		/*
1117 		 * Allocate RDDM table for debugging purpose if specified
1118 		 */
1119 		mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
1120 				     mhi_cntrl->rddm_size);
1121 		if (mhi_cntrl->rddm_image)
1122 			mhi_rddm_prepare(mhi_cntrl, mhi_cntrl->rddm_image);
1123 	}
1124 
1125 	mutex_unlock(&mhi_cntrl->pm_mutex);
1126 
1127 	return 0;
1128 
1129 error_reg_offset:
1130 	mhi_deinit_dev_ctxt(mhi_cntrl);
1131 
1132 error_dev_ctxt:
1133 	mutex_unlock(&mhi_cntrl->pm_mutex);
1134 
1135 	return ret;
1136 }
1137 EXPORT_SYMBOL_GPL(mhi_prepare_for_power_up);
1138 
mhi_unprepare_after_power_down(struct mhi_controller * mhi_cntrl)1139 void mhi_unprepare_after_power_down(struct mhi_controller *mhi_cntrl)
1140 {
1141 	if (mhi_cntrl->fbc_image) {
1142 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
1143 		mhi_cntrl->fbc_image = NULL;
1144 	}
1145 
1146 	if (mhi_cntrl->rddm_image) {
1147 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->rddm_image);
1148 		mhi_cntrl->rddm_image = NULL;
1149 	}
1150 
1151 	mhi_cntrl->bhi = NULL;
1152 	mhi_cntrl->bhie = NULL;
1153 
1154 	mhi_deinit_dev_ctxt(mhi_cntrl);
1155 }
1156 EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
1157 
mhi_release_device(struct device * dev)1158 static void mhi_release_device(struct device *dev)
1159 {
1160 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1161 
1162 	/*
1163 	 * We need to set the mhi_chan->mhi_dev to NULL here since the MHI
1164 	 * devices for the channels will only get created if the mhi_dev
1165 	 * associated with it is NULL. This scenario will happen during the
1166 	 * controller suspend and resume.
1167 	 */
1168 	if (mhi_dev->ul_chan)
1169 		mhi_dev->ul_chan->mhi_dev = NULL;
1170 
1171 	if (mhi_dev->dl_chan)
1172 		mhi_dev->dl_chan->mhi_dev = NULL;
1173 
1174 	kfree(mhi_dev);
1175 }
1176 
mhi_alloc_device(struct mhi_controller * mhi_cntrl)1177 struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl)
1178 {
1179 	struct mhi_device *mhi_dev;
1180 	struct device *dev;
1181 
1182 	mhi_dev = kzalloc(sizeof(*mhi_dev), GFP_KERNEL);
1183 	if (!mhi_dev)
1184 		return ERR_PTR(-ENOMEM);
1185 
1186 	dev = &mhi_dev->dev;
1187 	device_initialize(dev);
1188 	dev->bus = &mhi_bus_type;
1189 	dev->release = mhi_release_device;
1190 
1191 	if (mhi_cntrl->mhi_dev) {
1192 		/* for MHI client devices, parent is the MHI controller device */
1193 		dev->parent = &mhi_cntrl->mhi_dev->dev;
1194 	} else {
1195 		/* for MHI controller device, parent is the bus device (e.g. pci device) */
1196 		dev->parent = mhi_cntrl->cntrl_dev;
1197 	}
1198 
1199 	mhi_dev->mhi_cntrl = mhi_cntrl;
1200 	mhi_dev->dev_wake = 0;
1201 
1202 	return mhi_dev;
1203 }
1204 
mhi_driver_probe(struct device * dev)1205 static int mhi_driver_probe(struct device *dev)
1206 {
1207 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1208 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
1209 	struct device_driver *drv = dev->driver;
1210 	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
1211 	struct mhi_event *mhi_event;
1212 	struct mhi_chan *ul_chan = mhi_dev->ul_chan;
1213 	struct mhi_chan *dl_chan = mhi_dev->dl_chan;
1214 	int ret;
1215 
1216 	/* Bring device out of LPM */
1217 	ret = mhi_device_get_sync(mhi_dev);
1218 	if (ret)
1219 		return ret;
1220 
1221 	ret = -EINVAL;
1222 
1223 	if (ul_chan) {
1224 		/*
1225 		 * If channel supports LPM notifications then status_cb should
1226 		 * be provided
1227 		 */
1228 		if (ul_chan->lpm_notify && !mhi_drv->status_cb)
1229 			goto exit_probe;
1230 
1231 		/* For non-offload channels then xfer_cb should be provided */
1232 		if (!ul_chan->offload_ch && !mhi_drv->ul_xfer_cb)
1233 			goto exit_probe;
1234 
1235 		ul_chan->xfer_cb = mhi_drv->ul_xfer_cb;
1236 	}
1237 
1238 	ret = -EINVAL;
1239 	if (dl_chan) {
1240 		/*
1241 		 * If channel supports LPM notifications then status_cb should
1242 		 * be provided
1243 		 */
1244 		if (dl_chan->lpm_notify && !mhi_drv->status_cb)
1245 			goto exit_probe;
1246 
1247 		/* For non-offload channels then xfer_cb should be provided */
1248 		if (!dl_chan->offload_ch && !mhi_drv->dl_xfer_cb)
1249 			goto exit_probe;
1250 
1251 		mhi_event = &mhi_cntrl->mhi_event[dl_chan->er_index];
1252 
1253 		/*
1254 		 * If the channel event ring is managed by client, then
1255 		 * status_cb must be provided so that the framework can
1256 		 * notify pending data
1257 		 */
1258 		if (mhi_event->cl_manage && !mhi_drv->status_cb)
1259 			goto exit_probe;
1260 
1261 		dl_chan->xfer_cb = mhi_drv->dl_xfer_cb;
1262 	}
1263 
1264 	/* Call the user provided probe function */
1265 	ret = mhi_drv->probe(mhi_dev, mhi_dev->id);
1266 	if (ret)
1267 		goto exit_probe;
1268 
1269 	mhi_device_put(mhi_dev);
1270 
1271 	return ret;
1272 
1273 exit_probe:
1274 	mhi_unprepare_from_transfer(mhi_dev);
1275 
1276 	mhi_device_put(mhi_dev);
1277 
1278 	return ret;
1279 }
1280 
mhi_driver_remove(struct device * dev)1281 static int mhi_driver_remove(struct device *dev)
1282 {
1283 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1284 	struct mhi_driver *mhi_drv = to_mhi_driver(dev->driver);
1285 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
1286 	struct mhi_chan *mhi_chan;
1287 	enum mhi_ch_state ch_state[] = {
1288 		MHI_CH_STATE_DISABLED,
1289 		MHI_CH_STATE_DISABLED
1290 	};
1291 	int dir;
1292 
1293 	/* Skip if it is a controller device */
1294 	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
1295 		return 0;
1296 
1297 	/* Reset both channels */
1298 	for (dir = 0; dir < 2; dir++) {
1299 		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
1300 
1301 		if (!mhi_chan)
1302 			continue;
1303 
1304 		/* Wake all threads waiting for completion */
1305 		write_lock_irq(&mhi_chan->lock);
1306 		mhi_chan->ccs = MHI_EV_CC_INVALID;
1307 		complete_all(&mhi_chan->completion);
1308 		write_unlock_irq(&mhi_chan->lock);
1309 
1310 		/* Set the channel state to disabled */
1311 		mutex_lock(&mhi_chan->mutex);
1312 		write_lock_irq(&mhi_chan->lock);
1313 		ch_state[dir] = mhi_chan->ch_state;
1314 		mhi_chan->ch_state = MHI_CH_STATE_SUSPENDED;
1315 		write_unlock_irq(&mhi_chan->lock);
1316 
1317 		/* Reset the non-offload channel */
1318 		if (!mhi_chan->offload_ch)
1319 			mhi_reset_chan(mhi_cntrl, mhi_chan);
1320 
1321 		mutex_unlock(&mhi_chan->mutex);
1322 	}
1323 
1324 	mhi_drv->remove(mhi_dev);
1325 
1326 	/* De-init channel if it was enabled */
1327 	for (dir = 0; dir < 2; dir++) {
1328 		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
1329 
1330 		if (!mhi_chan)
1331 			continue;
1332 
1333 		mutex_lock(&mhi_chan->mutex);
1334 
1335 		if ((ch_state[dir] == MHI_CH_STATE_ENABLED ||
1336 		     ch_state[dir] == MHI_CH_STATE_STOP) &&
1337 		    !mhi_chan->offload_ch)
1338 			mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
1339 
1340 		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
1341 
1342 		mutex_unlock(&mhi_chan->mutex);
1343 	}
1344 
1345 	while (mhi_dev->dev_wake)
1346 		mhi_device_put(mhi_dev);
1347 
1348 	return 0;
1349 }
1350 
__mhi_driver_register(struct mhi_driver * mhi_drv,struct module * owner)1351 int __mhi_driver_register(struct mhi_driver *mhi_drv, struct module *owner)
1352 {
1353 	struct device_driver *driver = &mhi_drv->driver;
1354 
1355 	if (!mhi_drv->probe || !mhi_drv->remove)
1356 		return -EINVAL;
1357 
1358 	driver->bus = &mhi_bus_type;
1359 	driver->owner = owner;
1360 	driver->probe = mhi_driver_probe;
1361 	driver->remove = mhi_driver_remove;
1362 
1363 	return driver_register(driver);
1364 }
1365 EXPORT_SYMBOL_GPL(__mhi_driver_register);
1366 
mhi_driver_unregister(struct mhi_driver * mhi_drv)1367 void mhi_driver_unregister(struct mhi_driver *mhi_drv)
1368 {
1369 	driver_unregister(&mhi_drv->driver);
1370 }
1371 EXPORT_SYMBOL_GPL(mhi_driver_unregister);
1372 
mhi_uevent(struct device * dev,struct kobj_uevent_env * env)1373 static int mhi_uevent(struct device *dev, struct kobj_uevent_env *env)
1374 {
1375 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1376 
1377 	return add_uevent_var(env, "MODALIAS=" MHI_DEVICE_MODALIAS_FMT,
1378 					mhi_dev->name);
1379 }
1380 
mhi_match(struct device * dev,struct device_driver * drv)1381 static int mhi_match(struct device *dev, struct device_driver *drv)
1382 {
1383 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1384 	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
1385 	const struct mhi_device_id *id;
1386 
1387 	/*
1388 	 * If the device is a controller type then there is no client driver
1389 	 * associated with it
1390 	 */
1391 	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
1392 		return 0;
1393 
1394 	for (id = mhi_drv->id_table; id->chan[0]; id++)
1395 		if (!strcmp(mhi_dev->name, id->chan)) {
1396 			mhi_dev->id = id;
1397 			return 1;
1398 		}
1399 
1400 	return 0;
1401 };
1402 
1403 struct bus_type mhi_bus_type = {
1404 	.name = "mhi",
1405 	.dev_name = "mhi",
1406 	.match = mhi_match,
1407 	.uevent = mhi_uevent,
1408 	.dev_groups = mhi_dev_groups,
1409 };
1410 
mhi_init(void)1411 static int __init mhi_init(void)
1412 {
1413 	mhi_debugfs_init();
1414 	return bus_register(&mhi_bus_type);
1415 }
1416 
mhi_exit(void)1417 static void __exit mhi_exit(void)
1418 {
1419 	mhi_debugfs_exit();
1420 	bus_unregister(&mhi_bus_type);
1421 }
1422 
1423 postcore_initcall(mhi_init);
1424 module_exit(mhi_exit);
1425 
1426 MODULE_LICENSE("GPL v2");
1427 MODULE_DESCRIPTION("MHI Host Interface");
1428