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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/bitfield.h>
8 #include <linux/debugfs.h>
9 #include <linux/device.h>
10 #include <linux/dma-direction.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/idr.h>
13 #include <linux/interrupt.h>
14 #include <linux/list.h>
15 #include <linux/mhi.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/vmalloc.h>
20 #include <linux/wait.h>
21 #include "internal.h"
22 
23 static DEFINE_IDA(mhi_controller_ida);
24 
25 const char * const mhi_ee_str[MHI_EE_MAX] = {
26 	[MHI_EE_PBL] = "PRIMARY BOOTLOADER",
27 	[MHI_EE_SBL] = "SECONDARY BOOTLOADER",
28 	[MHI_EE_AMSS] = "MISSION MODE",
29 	[MHI_EE_RDDM] = "RAMDUMP DOWNLOAD MODE",
30 	[MHI_EE_WFW] = "WLAN FIRMWARE",
31 	[MHI_EE_PTHRU] = "PASS THROUGH",
32 	[MHI_EE_EDL] = "EMERGENCY DOWNLOAD",
33 	[MHI_EE_FP] = "FLASH PROGRAMMER",
34 	[MHI_EE_DISABLE_TRANSITION] = "DISABLE",
35 	[MHI_EE_NOT_SUPPORTED] = "NOT SUPPORTED",
36 };
37 
38 const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
39 	[DEV_ST_TRANSITION_PBL] = "PBL",
40 	[DEV_ST_TRANSITION_READY] = "READY",
41 	[DEV_ST_TRANSITION_SBL] = "SBL",
42 	[DEV_ST_TRANSITION_MISSION_MODE] = "MISSION MODE",
43 	[DEV_ST_TRANSITION_FP] = "FLASH PROGRAMMER",
44 	[DEV_ST_TRANSITION_SYS_ERR] = "SYS ERROR",
45 	[DEV_ST_TRANSITION_DISABLE] = "DISABLE",
46 };
47 
48 const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX] = {
49 	[MHI_CH_STATE_TYPE_RESET] = "RESET",
50 	[MHI_CH_STATE_TYPE_STOP] = "STOP",
51 	[MHI_CH_STATE_TYPE_START] = "START",
52 };
53 
54 static const char * const mhi_pm_state_str[] = {
55 	[MHI_PM_STATE_DISABLE] = "DISABLE",
56 	[MHI_PM_STATE_POR] = "POWER ON RESET",
57 	[MHI_PM_STATE_M0] = "M0",
58 	[MHI_PM_STATE_M2] = "M2",
59 	[MHI_PM_STATE_M3_ENTER] = "M?->M3",
60 	[MHI_PM_STATE_M3] = "M3",
61 	[MHI_PM_STATE_M3_EXIT] = "M3->M0",
62 	[MHI_PM_STATE_FW_DL_ERR] = "Firmware Download Error",
63 	[MHI_PM_STATE_SYS_ERR_DETECT] = "SYS ERROR Detect",
64 	[MHI_PM_STATE_SYS_ERR_PROCESS] = "SYS ERROR Process",
65 	[MHI_PM_STATE_SHUTDOWN_PROCESS] = "SHUTDOWN Process",
66 	[MHI_PM_STATE_LD_ERR_FATAL_DETECT] = "Linkdown or Error Fatal Detect",
67 };
68 
to_mhi_pm_state_str(u32 state)69 const char *to_mhi_pm_state_str(u32 state)
70 {
71 	int index;
72 
73 	if (state)
74 		index = __fls(state);
75 
76 	if (!state || index >= ARRAY_SIZE(mhi_pm_state_str))
77 		return "Invalid State";
78 
79 	return mhi_pm_state_str[index];
80 }
81 
serial_number_show(struct device * dev,struct device_attribute * attr,char * buf)82 static ssize_t serial_number_show(struct device *dev,
83 				  struct device_attribute *attr,
84 				  char *buf)
85 {
86 	struct mhi_device *mhi_dev = to_mhi_device(dev);
87 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
88 
89 	return sysfs_emit(buf, "Serial Number: %u\n",
90 			mhi_cntrl->serial_number);
91 }
92 static DEVICE_ATTR_RO(serial_number);
93 
oem_pk_hash_show(struct device * dev,struct device_attribute * attr,char * buf)94 static ssize_t oem_pk_hash_show(struct device *dev,
95 				struct device_attribute *attr,
96 				char *buf)
97 {
98 	struct mhi_device *mhi_dev = to_mhi_device(dev);
99 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
100 	int i, cnt = 0;
101 
102 	for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++)
103 		cnt += sysfs_emit_at(buf, cnt, "OEMPKHASH[%d]: 0x%x\n",
104 				i, mhi_cntrl->oem_pk_hash[i]);
105 
106 	return cnt;
107 }
108 static DEVICE_ATTR_RO(oem_pk_hash);
109 
soc_reset_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)110 static ssize_t soc_reset_store(struct device *dev,
111 			       struct device_attribute *attr,
112 			       const char *buf,
113 			       size_t count)
114 {
115 	struct mhi_device *mhi_dev = to_mhi_device(dev);
116 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
117 
118 	mhi_soc_reset(mhi_cntrl);
119 	return count;
120 }
121 static DEVICE_ATTR_WO(soc_reset);
122 
123 static struct attribute *mhi_dev_attrs[] = {
124 	&dev_attr_serial_number.attr,
125 	&dev_attr_oem_pk_hash.attr,
126 	&dev_attr_soc_reset.attr,
127 	NULL,
128 };
129 ATTRIBUTE_GROUPS(mhi_dev);
130 
131 /* 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)132 static int mhi_alloc_aligned_ring(struct mhi_controller *mhi_cntrl,
133 				  struct mhi_ring *ring,
134 				  u64 len)
135 {
136 	ring->alloc_size = len + (len - 1);
137 	ring->pre_aligned = dma_alloc_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
138 					       &ring->dma_handle, GFP_KERNEL);
139 	if (!ring->pre_aligned)
140 		return -ENOMEM;
141 
142 	ring->iommu_base = (ring->dma_handle + (len - 1)) & ~(len - 1);
143 	ring->base = ring->pre_aligned + (ring->iommu_base - ring->dma_handle);
144 
145 	return 0;
146 }
147 
mhi_deinit_free_irq(struct mhi_controller * mhi_cntrl)148 void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl)
149 {
150 	int i;
151 	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
152 
153 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
154 		if (mhi_event->offload_ev)
155 			continue;
156 
157 		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
158 	}
159 
160 	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
161 }
162 
mhi_init_irq_setup(struct mhi_controller * mhi_cntrl)163 int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl)
164 {
165 	struct mhi_event *mhi_event = mhi_cntrl->mhi_event;
166 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
167 	unsigned long irq_flags = IRQF_SHARED | IRQF_NO_SUSPEND;
168 	int i, ret;
169 
170 	/* if controller driver has set irq_flags, use it */
171 	if (mhi_cntrl->irq_flags)
172 		irq_flags = mhi_cntrl->irq_flags;
173 
174 	/* Setup BHI_INTVEC IRQ */
175 	ret = request_threaded_irq(mhi_cntrl->irq[0], mhi_intvec_handler,
176 				   mhi_intvec_threaded_handler,
177 				   irq_flags,
178 				   "bhi", mhi_cntrl);
179 	if (ret)
180 		return ret;
181 	/*
182 	 * IRQs should be enabled during mhi_async_power_up(), so disable them explicitly here.
183 	 * Due to the use of IRQF_SHARED flag as default while requesting IRQs, we assume that
184 	 * IRQ_NOAUTOEN is not applicable.
185 	 */
186 	disable_irq(mhi_cntrl->irq[0]);
187 
188 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
189 		if (mhi_event->offload_ev)
190 			continue;
191 
192 		if (mhi_event->irq >= mhi_cntrl->nr_irqs) {
193 			dev_err(dev, "irq %d not available for event ring\n",
194 				mhi_event->irq);
195 			ret = -EINVAL;
196 			goto error_request;
197 		}
198 
199 		ret = request_irq(mhi_cntrl->irq[mhi_event->irq],
200 				  mhi_irq_handler,
201 				  irq_flags,
202 				  "mhi", mhi_event);
203 		if (ret) {
204 			dev_err(dev, "Error requesting irq:%d for ev:%d\n",
205 				mhi_cntrl->irq[mhi_event->irq], i);
206 			goto error_request;
207 		}
208 
209 		disable_irq(mhi_cntrl->irq[mhi_event->irq]);
210 	}
211 
212 	return 0;
213 
214 error_request:
215 	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
216 		if (mhi_event->offload_ev)
217 			continue;
218 
219 		free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event);
220 	}
221 	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
222 
223 	return ret;
224 }
225 
mhi_deinit_dev_ctxt(struct mhi_controller * mhi_cntrl)226 void mhi_deinit_dev_ctxt(struct mhi_controller *mhi_cntrl)
227 {
228 	int i;
229 	struct mhi_ctxt *mhi_ctxt = mhi_cntrl->mhi_ctxt;
230 	struct mhi_cmd *mhi_cmd;
231 	struct mhi_event *mhi_event;
232 	struct mhi_ring *ring;
233 
234 	mhi_cmd = mhi_cntrl->mhi_cmd;
235 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++) {
236 		ring = &mhi_cmd->ring;
237 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
238 				  ring->pre_aligned, ring->dma_handle);
239 		ring->base = NULL;
240 		ring->iommu_base = 0;
241 	}
242 
243 	dma_free_coherent(mhi_cntrl->cntrl_dev,
244 			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
245 			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
246 
247 	mhi_event = mhi_cntrl->mhi_event;
248 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
249 		if (mhi_event->offload_ev)
250 			continue;
251 
252 		ring = &mhi_event->ring;
253 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
254 				  ring->pre_aligned, ring->dma_handle);
255 		ring->base = NULL;
256 		ring->iommu_base = 0;
257 	}
258 
259 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
260 			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
261 			  mhi_ctxt->er_ctxt_addr);
262 
263 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
264 			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
265 			  mhi_ctxt->chan_ctxt_addr);
266 
267 	kfree(mhi_ctxt);
268 	mhi_cntrl->mhi_ctxt = NULL;
269 }
270 
mhi_init_dev_ctxt(struct mhi_controller * mhi_cntrl)271 int mhi_init_dev_ctxt(struct mhi_controller *mhi_cntrl)
272 {
273 	struct mhi_ctxt *mhi_ctxt;
274 	struct mhi_chan_ctxt *chan_ctxt;
275 	struct mhi_event_ctxt *er_ctxt;
276 	struct mhi_cmd_ctxt *cmd_ctxt;
277 	struct mhi_chan *mhi_chan;
278 	struct mhi_event *mhi_event;
279 	struct mhi_cmd *mhi_cmd;
280 	u32 tmp;
281 	int ret = -ENOMEM, i;
282 
283 	atomic_set(&mhi_cntrl->dev_wake, 0);
284 	atomic_set(&mhi_cntrl->pending_pkts, 0);
285 
286 	mhi_ctxt = kzalloc(sizeof(*mhi_ctxt), GFP_KERNEL);
287 	if (!mhi_ctxt)
288 		return -ENOMEM;
289 
290 	/* Setup channel ctxt */
291 	mhi_ctxt->chan_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
292 						 sizeof(*mhi_ctxt->chan_ctxt) *
293 						 mhi_cntrl->max_chan,
294 						 &mhi_ctxt->chan_ctxt_addr,
295 						 GFP_KERNEL);
296 	if (!mhi_ctxt->chan_ctxt)
297 		goto error_alloc_chan_ctxt;
298 
299 	mhi_chan = mhi_cntrl->mhi_chan;
300 	chan_ctxt = mhi_ctxt->chan_ctxt;
301 	for (i = 0; i < mhi_cntrl->max_chan; i++, chan_ctxt++, mhi_chan++) {
302 		/* Skip if it is an offload channel */
303 		if (mhi_chan->offload_ch)
304 			continue;
305 
306 		tmp = le32_to_cpu(chan_ctxt->chcfg);
307 		tmp &= ~CHAN_CTX_CHSTATE_MASK;
308 		tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED);
309 		tmp &= ~CHAN_CTX_BRSTMODE_MASK;
310 		tmp |= FIELD_PREP(CHAN_CTX_BRSTMODE_MASK, mhi_chan->db_cfg.brstmode);
311 		tmp &= ~CHAN_CTX_POLLCFG_MASK;
312 		tmp |= FIELD_PREP(CHAN_CTX_POLLCFG_MASK, mhi_chan->db_cfg.pollcfg);
313 		chan_ctxt->chcfg = cpu_to_le32(tmp);
314 
315 		chan_ctxt->chtype = cpu_to_le32(mhi_chan->type);
316 		chan_ctxt->erindex = cpu_to_le32(mhi_chan->er_index);
317 
318 		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
319 		mhi_chan->tre_ring.db_addr = (void __iomem *)&chan_ctxt->wp;
320 	}
321 
322 	/* Setup event context */
323 	mhi_ctxt->er_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
324 					       sizeof(*mhi_ctxt->er_ctxt) *
325 					       mhi_cntrl->total_ev_rings,
326 					       &mhi_ctxt->er_ctxt_addr,
327 					       GFP_KERNEL);
328 	if (!mhi_ctxt->er_ctxt)
329 		goto error_alloc_er_ctxt;
330 
331 	er_ctxt = mhi_ctxt->er_ctxt;
332 	mhi_event = mhi_cntrl->mhi_event;
333 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++,
334 		     mhi_event++) {
335 		struct mhi_ring *ring = &mhi_event->ring;
336 
337 		/* Skip if it is an offload event */
338 		if (mhi_event->offload_ev)
339 			continue;
340 
341 		tmp = le32_to_cpu(er_ctxt->intmod);
342 		tmp &= ~EV_CTX_INTMODC_MASK;
343 		tmp &= ~EV_CTX_INTMODT_MASK;
344 		tmp |= FIELD_PREP(EV_CTX_INTMODT_MASK, mhi_event->intmod);
345 		er_ctxt->intmod = cpu_to_le32(tmp);
346 
347 		er_ctxt->ertype = cpu_to_le32(MHI_ER_TYPE_VALID);
348 		er_ctxt->msivec = cpu_to_le32(mhi_event->irq);
349 		mhi_event->db_cfg.db_mode = true;
350 
351 		ring->el_size = sizeof(struct mhi_ring_element);
352 		ring->len = ring->el_size * ring->elements;
353 		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
354 		if (ret)
355 			goto error_alloc_er;
356 
357 		/*
358 		 * If the read pointer equals to the write pointer, then the
359 		 * ring is empty
360 		 */
361 		ring->rp = ring->wp = ring->base;
362 		er_ctxt->rbase = cpu_to_le64(ring->iommu_base);
363 		er_ctxt->rp = er_ctxt->wp = er_ctxt->rbase;
364 		er_ctxt->rlen = cpu_to_le64(ring->len);
365 		ring->ctxt_wp = &er_ctxt->wp;
366 	}
367 
368 	/* Setup cmd context */
369 	ret = -ENOMEM;
370 	mhi_ctxt->cmd_ctxt = dma_alloc_coherent(mhi_cntrl->cntrl_dev,
371 						sizeof(*mhi_ctxt->cmd_ctxt) *
372 						NR_OF_CMD_RINGS,
373 						&mhi_ctxt->cmd_ctxt_addr,
374 						GFP_KERNEL);
375 	if (!mhi_ctxt->cmd_ctxt)
376 		goto error_alloc_er;
377 
378 	mhi_cmd = mhi_cntrl->mhi_cmd;
379 	cmd_ctxt = mhi_ctxt->cmd_ctxt;
380 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) {
381 		struct mhi_ring *ring = &mhi_cmd->ring;
382 
383 		ring->el_size = sizeof(struct mhi_ring_element);
384 		ring->elements = CMD_EL_PER_RING;
385 		ring->len = ring->el_size * ring->elements;
386 		ret = mhi_alloc_aligned_ring(mhi_cntrl, ring, ring->len);
387 		if (ret)
388 			goto error_alloc_cmd;
389 
390 		ring->rp = ring->wp = ring->base;
391 		cmd_ctxt->rbase = cpu_to_le64(ring->iommu_base);
392 		cmd_ctxt->rp = cmd_ctxt->wp = cmd_ctxt->rbase;
393 		cmd_ctxt->rlen = cpu_to_le64(ring->len);
394 		ring->ctxt_wp = &cmd_ctxt->wp;
395 	}
396 
397 	mhi_cntrl->mhi_ctxt = mhi_ctxt;
398 
399 	return 0;
400 
401 error_alloc_cmd:
402 	for (--i, --mhi_cmd; i >= 0; i--, mhi_cmd--) {
403 		struct mhi_ring *ring = &mhi_cmd->ring;
404 
405 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
406 				  ring->pre_aligned, ring->dma_handle);
407 	}
408 	dma_free_coherent(mhi_cntrl->cntrl_dev,
409 			  sizeof(*mhi_ctxt->cmd_ctxt) * NR_OF_CMD_RINGS,
410 			  mhi_ctxt->cmd_ctxt, mhi_ctxt->cmd_ctxt_addr);
411 	i = mhi_cntrl->total_ev_rings;
412 	mhi_event = mhi_cntrl->mhi_event + i;
413 
414 error_alloc_er:
415 	for (--i, --mhi_event; i >= 0; i--, mhi_event--) {
416 		struct mhi_ring *ring = &mhi_event->ring;
417 
418 		if (mhi_event->offload_ev)
419 			continue;
420 
421 		dma_free_coherent(mhi_cntrl->cntrl_dev, ring->alloc_size,
422 				  ring->pre_aligned, ring->dma_handle);
423 	}
424 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->er_ctxt) *
425 			  mhi_cntrl->total_ev_rings, mhi_ctxt->er_ctxt,
426 			  mhi_ctxt->er_ctxt_addr);
427 
428 error_alloc_er_ctxt:
429 	dma_free_coherent(mhi_cntrl->cntrl_dev, sizeof(*mhi_ctxt->chan_ctxt) *
430 			  mhi_cntrl->max_chan, mhi_ctxt->chan_ctxt,
431 			  mhi_ctxt->chan_ctxt_addr);
432 
433 error_alloc_chan_ctxt:
434 	kfree(mhi_ctxt);
435 
436 	return ret;
437 }
438 
mhi_init_mmio(struct mhi_controller * mhi_cntrl)439 int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
440 {
441 	u32 val;
442 	int i, ret;
443 	struct mhi_chan *mhi_chan;
444 	struct mhi_event *mhi_event;
445 	void __iomem *base = mhi_cntrl->regs;
446 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
447 	struct {
448 		u32 offset;
449 		u32 val;
450 	} reg_info[] = {
451 		{
452 			CCABAP_HIGHER,
453 			upper_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
454 		},
455 		{
456 			CCABAP_LOWER,
457 			lower_32_bits(mhi_cntrl->mhi_ctxt->chan_ctxt_addr),
458 		},
459 		{
460 			ECABAP_HIGHER,
461 			upper_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
462 		},
463 		{
464 			ECABAP_LOWER,
465 			lower_32_bits(mhi_cntrl->mhi_ctxt->er_ctxt_addr),
466 		},
467 		{
468 			CRCBAP_HIGHER,
469 			upper_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
470 		},
471 		{
472 			CRCBAP_LOWER,
473 			lower_32_bits(mhi_cntrl->mhi_ctxt->cmd_ctxt_addr),
474 		},
475 		{
476 			MHICTRLBASE_HIGHER,
477 			upper_32_bits(mhi_cntrl->iova_start),
478 		},
479 		{
480 			MHICTRLBASE_LOWER,
481 			lower_32_bits(mhi_cntrl->iova_start),
482 		},
483 		{
484 			MHIDATABASE_HIGHER,
485 			upper_32_bits(mhi_cntrl->iova_start),
486 		},
487 		{
488 			MHIDATABASE_LOWER,
489 			lower_32_bits(mhi_cntrl->iova_start),
490 		},
491 		{
492 			MHICTRLLIMIT_HIGHER,
493 			upper_32_bits(mhi_cntrl->iova_stop),
494 		},
495 		{
496 			MHICTRLLIMIT_LOWER,
497 			lower_32_bits(mhi_cntrl->iova_stop),
498 		},
499 		{
500 			MHIDATALIMIT_HIGHER,
501 			upper_32_bits(mhi_cntrl->iova_stop),
502 		},
503 		{
504 			MHIDATALIMIT_LOWER,
505 			lower_32_bits(mhi_cntrl->iova_stop),
506 		},
507 		{0, 0}
508 	};
509 
510 	dev_dbg(dev, "Initializing MHI registers\n");
511 
512 	/* Read channel db offset */
513 	ret = mhi_read_reg(mhi_cntrl, base, CHDBOFF, &val);
514 	if (ret) {
515 		dev_err(dev, "Unable to read CHDBOFF register\n");
516 		return -EIO;
517 	}
518 
519 	if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
520 		dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
521 			val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
522 		return -ERANGE;
523 	}
524 
525 	/* Setup wake db */
526 	mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
527 	mhi_cntrl->wake_set = false;
528 
529 	/* Setup channel db address for each channel in tre_ring */
530 	mhi_chan = mhi_cntrl->mhi_chan;
531 	for (i = 0; i < mhi_cntrl->max_chan; i++, val += 8, mhi_chan++)
532 		mhi_chan->tre_ring.db_addr = base + val;
533 
534 	/* Read event ring db offset */
535 	ret = mhi_read_reg(mhi_cntrl, base, ERDBOFF, &val);
536 	if (ret) {
537 		dev_err(dev, "Unable to read ERDBOFF register\n");
538 		return -EIO;
539 	}
540 
541 	if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
542 		dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
543 			val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
544 		return -ERANGE;
545 	}
546 
547 	/* Setup event db address for each ev_ring */
548 	mhi_event = mhi_cntrl->mhi_event;
549 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
550 		if (mhi_event->offload_ev)
551 			continue;
552 
553 		mhi_event->ring.db_addr = base + val;
554 	}
555 
556 	/* Setup DB register for primary CMD rings */
557 	mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING].ring.db_addr = base + CRDB_LOWER;
558 
559 	/* Write to MMIO registers */
560 	for (i = 0; reg_info[i].offset; i++)
561 		mhi_write_reg(mhi_cntrl, base, reg_info[i].offset,
562 			      reg_info[i].val);
563 
564 	ret = mhi_write_reg_field(mhi_cntrl, base, MHICFG, MHICFG_NER_MASK,
565 				  mhi_cntrl->total_ev_rings);
566 	if (ret) {
567 		dev_err(dev, "Unable to write MHICFG register\n");
568 		return ret;
569 	}
570 
571 	ret = mhi_write_reg_field(mhi_cntrl, base, MHICFG, MHICFG_NHWER_MASK,
572 				  mhi_cntrl->hw_ev_rings);
573 	if (ret) {
574 		dev_err(dev, "Unable to write MHICFG register\n");
575 		return ret;
576 	}
577 
578 	return 0;
579 }
580 
mhi_deinit_chan_ctxt(struct mhi_controller * mhi_cntrl,struct mhi_chan * mhi_chan)581 void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
582 			  struct mhi_chan *mhi_chan)
583 {
584 	struct mhi_ring *buf_ring;
585 	struct mhi_ring *tre_ring;
586 	struct mhi_chan_ctxt *chan_ctxt;
587 	u32 tmp;
588 
589 	buf_ring = &mhi_chan->buf_ring;
590 	tre_ring = &mhi_chan->tre_ring;
591 	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
592 
593 	if (!chan_ctxt->rbase) /* Already uninitialized */
594 		return;
595 
596 	dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
597 			  tre_ring->pre_aligned, tre_ring->dma_handle);
598 	vfree(buf_ring->base);
599 
600 	buf_ring->base = tre_ring->base = NULL;
601 	tre_ring->ctxt_wp = NULL;
602 	chan_ctxt->rbase = 0;
603 	chan_ctxt->rlen = 0;
604 	chan_ctxt->rp = 0;
605 	chan_ctxt->wp = 0;
606 
607 	tmp = le32_to_cpu(chan_ctxt->chcfg);
608 	tmp &= ~CHAN_CTX_CHSTATE_MASK;
609 	tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED);
610 	chan_ctxt->chcfg = cpu_to_le32(tmp);
611 
612 	/* Update to all cores */
613 	smp_wmb();
614 }
615 
mhi_init_chan_ctxt(struct mhi_controller * mhi_cntrl,struct mhi_chan * mhi_chan)616 int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
617 		       struct mhi_chan *mhi_chan)
618 {
619 	struct mhi_ring *buf_ring;
620 	struct mhi_ring *tre_ring;
621 	struct mhi_chan_ctxt *chan_ctxt;
622 	u32 tmp;
623 	int ret;
624 
625 	buf_ring = &mhi_chan->buf_ring;
626 	tre_ring = &mhi_chan->tre_ring;
627 	tre_ring->el_size = sizeof(struct mhi_ring_element);
628 	tre_ring->len = tre_ring->el_size * tre_ring->elements;
629 	chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
630 	ret = mhi_alloc_aligned_ring(mhi_cntrl, tre_ring, tre_ring->len);
631 	if (ret)
632 		return -ENOMEM;
633 
634 	buf_ring->el_size = sizeof(struct mhi_buf_info);
635 	buf_ring->len = buf_ring->el_size * buf_ring->elements;
636 	buf_ring->base = vzalloc(buf_ring->len);
637 
638 	if (!buf_ring->base) {
639 		dma_free_coherent(mhi_cntrl->cntrl_dev, tre_ring->alloc_size,
640 				  tre_ring->pre_aligned, tre_ring->dma_handle);
641 		return -ENOMEM;
642 	}
643 
644 	tmp = le32_to_cpu(chan_ctxt->chcfg);
645 	tmp &= ~CHAN_CTX_CHSTATE_MASK;
646 	tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_ENABLED);
647 	chan_ctxt->chcfg = cpu_to_le32(tmp);
648 
649 	chan_ctxt->rbase = cpu_to_le64(tre_ring->iommu_base);
650 	chan_ctxt->rp = chan_ctxt->wp = chan_ctxt->rbase;
651 	chan_ctxt->rlen = cpu_to_le64(tre_ring->len);
652 	tre_ring->ctxt_wp = &chan_ctxt->wp;
653 
654 	tre_ring->rp = tre_ring->wp = tre_ring->base;
655 	buf_ring->rp = buf_ring->wp = buf_ring->base;
656 	mhi_chan->db_cfg.db_mode = 1;
657 
658 	/* Update to all cores */
659 	smp_wmb();
660 
661 	return 0;
662 }
663 
parse_ev_cfg(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)664 static int parse_ev_cfg(struct mhi_controller *mhi_cntrl,
665 			const struct mhi_controller_config *config)
666 {
667 	struct mhi_event *mhi_event;
668 	const struct mhi_event_config *event_cfg;
669 	struct device *dev = mhi_cntrl->cntrl_dev;
670 	int i, num;
671 
672 	num = config->num_events;
673 	mhi_cntrl->total_ev_rings = num;
674 	mhi_cntrl->mhi_event = kcalloc(num, sizeof(*mhi_cntrl->mhi_event),
675 				       GFP_KERNEL);
676 	if (!mhi_cntrl->mhi_event)
677 		return -ENOMEM;
678 
679 	/* Populate event ring */
680 	mhi_event = mhi_cntrl->mhi_event;
681 	for (i = 0; i < num; i++) {
682 		event_cfg = &config->event_cfg[i];
683 
684 		mhi_event->er_index = i;
685 		mhi_event->ring.elements = event_cfg->num_elements;
686 		mhi_event->intmod = event_cfg->irq_moderation_ms;
687 		mhi_event->irq = event_cfg->irq;
688 
689 		if (event_cfg->channel != U32_MAX) {
690 			/* This event ring has a dedicated channel */
691 			mhi_event->chan = event_cfg->channel;
692 			if (mhi_event->chan >= mhi_cntrl->max_chan) {
693 				dev_err(dev,
694 					"Event Ring channel not available\n");
695 				goto error_ev_cfg;
696 			}
697 
698 			mhi_event->mhi_chan =
699 				&mhi_cntrl->mhi_chan[mhi_event->chan];
700 		}
701 
702 		/* Priority is fixed to 1 for now */
703 		mhi_event->priority = 1;
704 
705 		mhi_event->db_cfg.brstmode = event_cfg->mode;
706 		if (MHI_INVALID_BRSTMODE(mhi_event->db_cfg.brstmode))
707 			goto error_ev_cfg;
708 
709 		if (mhi_event->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
710 			mhi_event->db_cfg.process_db = mhi_db_brstmode;
711 		else
712 			mhi_event->db_cfg.process_db = mhi_db_brstmode_disable;
713 
714 		mhi_event->data_type = event_cfg->data_type;
715 
716 		switch (mhi_event->data_type) {
717 		case MHI_ER_DATA:
718 			mhi_event->process_event = mhi_process_data_event_ring;
719 			break;
720 		case MHI_ER_CTRL:
721 			mhi_event->process_event = mhi_process_ctrl_ev_ring;
722 			break;
723 		default:
724 			dev_err(dev, "Event Ring type not supported\n");
725 			goto error_ev_cfg;
726 		}
727 
728 		mhi_event->hw_ring = event_cfg->hardware_event;
729 		if (mhi_event->hw_ring)
730 			mhi_cntrl->hw_ev_rings++;
731 		else
732 			mhi_cntrl->sw_ev_rings++;
733 
734 		mhi_event->cl_manage = event_cfg->client_managed;
735 		mhi_event->offload_ev = event_cfg->offload_channel;
736 		mhi_event++;
737 	}
738 
739 	return 0;
740 
741 error_ev_cfg:
742 
743 	kfree(mhi_cntrl->mhi_event);
744 	return -EINVAL;
745 }
746 
parse_ch_cfg(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)747 static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
748 			const struct mhi_controller_config *config)
749 {
750 	const struct mhi_channel_config *ch_cfg;
751 	struct device *dev = mhi_cntrl->cntrl_dev;
752 	int i;
753 	u32 chan;
754 
755 	mhi_cntrl->max_chan = config->max_channels;
756 
757 	/*
758 	 * The allocation of MHI channels can exceed 32KB in some scenarios,
759 	 * so to avoid any memory possible allocation failures, vzalloc is
760 	 * used here
761 	 */
762 	mhi_cntrl->mhi_chan = vzalloc(mhi_cntrl->max_chan *
763 				      sizeof(*mhi_cntrl->mhi_chan));
764 	if (!mhi_cntrl->mhi_chan)
765 		return -ENOMEM;
766 
767 	INIT_LIST_HEAD(&mhi_cntrl->lpm_chans);
768 
769 	/* Populate channel configurations */
770 	for (i = 0; i < config->num_channels; i++) {
771 		struct mhi_chan *mhi_chan;
772 
773 		ch_cfg = &config->ch_cfg[i];
774 
775 		chan = ch_cfg->num;
776 		if (chan >= mhi_cntrl->max_chan) {
777 			dev_err(dev, "Channel %d not available\n", chan);
778 			goto error_chan_cfg;
779 		}
780 
781 		mhi_chan = &mhi_cntrl->mhi_chan[chan];
782 		mhi_chan->name = ch_cfg->name;
783 		mhi_chan->chan = chan;
784 
785 		mhi_chan->tre_ring.elements = ch_cfg->num_elements;
786 		if (!mhi_chan->tre_ring.elements)
787 			goto error_chan_cfg;
788 
789 		/*
790 		 * For some channels, local ring length should be bigger than
791 		 * the transfer ring length due to internal logical channels
792 		 * in device. So host can queue much more buffers than transfer
793 		 * ring length. Example, RSC channels should have a larger local
794 		 * channel length than transfer ring length.
795 		 */
796 		mhi_chan->buf_ring.elements = ch_cfg->local_elements;
797 		if (!mhi_chan->buf_ring.elements)
798 			mhi_chan->buf_ring.elements = mhi_chan->tre_ring.elements;
799 		mhi_chan->er_index = ch_cfg->event_ring;
800 		mhi_chan->dir = ch_cfg->dir;
801 
802 		/*
803 		 * For most channels, chtype is identical to channel directions.
804 		 * So, if it is not defined then assign channel direction to
805 		 * chtype
806 		 */
807 		mhi_chan->type = ch_cfg->type;
808 		if (!mhi_chan->type)
809 			mhi_chan->type = (enum mhi_ch_type)mhi_chan->dir;
810 
811 		mhi_chan->ee_mask = ch_cfg->ee_mask;
812 		mhi_chan->db_cfg.pollcfg = ch_cfg->pollcfg;
813 		mhi_chan->lpm_notify = ch_cfg->lpm_notify;
814 		mhi_chan->offload_ch = ch_cfg->offload_channel;
815 		mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
816 		mhi_chan->pre_alloc = ch_cfg->auto_queue;
817 		mhi_chan->wake_capable = ch_cfg->wake_capable;
818 
819 		/*
820 		 * If MHI host allocates buffers, then the channel direction
821 		 * should be DMA_FROM_DEVICE
822 		 */
823 		if (mhi_chan->pre_alloc && mhi_chan->dir != DMA_FROM_DEVICE) {
824 			dev_err(dev, "Invalid channel configuration\n");
825 			goto error_chan_cfg;
826 		}
827 
828 		/*
829 		 * Bi-directional and direction less channel must be an
830 		 * offload channel
831 		 */
832 		if ((mhi_chan->dir == DMA_BIDIRECTIONAL ||
833 		     mhi_chan->dir == DMA_NONE) && !mhi_chan->offload_ch) {
834 			dev_err(dev, "Invalid channel configuration\n");
835 			goto error_chan_cfg;
836 		}
837 
838 		if (!mhi_chan->offload_ch) {
839 			mhi_chan->db_cfg.brstmode = ch_cfg->doorbell;
840 			if (MHI_INVALID_BRSTMODE(mhi_chan->db_cfg.brstmode)) {
841 				dev_err(dev, "Invalid Door bell mode\n");
842 				goto error_chan_cfg;
843 			}
844 		}
845 
846 		if (mhi_chan->db_cfg.brstmode == MHI_DB_BRST_ENABLE)
847 			mhi_chan->db_cfg.process_db = mhi_db_brstmode;
848 		else
849 			mhi_chan->db_cfg.process_db = mhi_db_brstmode_disable;
850 
851 		mhi_chan->configured = true;
852 
853 		if (mhi_chan->lpm_notify)
854 			list_add_tail(&mhi_chan->node, &mhi_cntrl->lpm_chans);
855 	}
856 
857 	return 0;
858 
859 error_chan_cfg:
860 	vfree(mhi_cntrl->mhi_chan);
861 
862 	return -EINVAL;
863 }
864 
parse_config(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)865 static int parse_config(struct mhi_controller *mhi_cntrl,
866 			const struct mhi_controller_config *config)
867 {
868 	int ret;
869 
870 	/* Parse MHI channel configuration */
871 	ret = parse_ch_cfg(mhi_cntrl, config);
872 	if (ret)
873 		return ret;
874 
875 	/* Parse MHI event configuration */
876 	ret = parse_ev_cfg(mhi_cntrl, config);
877 	if (ret)
878 		goto error_ev_cfg;
879 
880 	mhi_cntrl->timeout_ms = config->timeout_ms;
881 	if (!mhi_cntrl->timeout_ms)
882 		mhi_cntrl->timeout_ms = MHI_TIMEOUT_MS;
883 
884 	mhi_cntrl->bounce_buf = config->use_bounce_buf;
885 	mhi_cntrl->buffer_len = config->buf_len;
886 	if (!mhi_cntrl->buffer_len)
887 		mhi_cntrl->buffer_len = MHI_MAX_MTU;
888 
889 	/* By default, host is allowed to ring DB in both M0 and M2 states */
890 	mhi_cntrl->db_access = MHI_PM_M0 | MHI_PM_M2;
891 	if (config->m2_no_db)
892 		mhi_cntrl->db_access &= ~MHI_PM_M2;
893 
894 	return 0;
895 
896 error_ev_cfg:
897 	vfree(mhi_cntrl->mhi_chan);
898 
899 	return ret;
900 }
901 
mhi_register_controller(struct mhi_controller * mhi_cntrl,const struct mhi_controller_config * config)902 int mhi_register_controller(struct mhi_controller *mhi_cntrl,
903 			    const struct mhi_controller_config *config)
904 {
905 	struct mhi_event *mhi_event;
906 	struct mhi_chan *mhi_chan;
907 	struct mhi_cmd *mhi_cmd;
908 	struct mhi_device *mhi_dev;
909 	u32 soc_info;
910 	int ret, i;
911 
912 	if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->regs ||
913 	    !mhi_cntrl->runtime_get || !mhi_cntrl->runtime_put ||
914 	    !mhi_cntrl->status_cb || !mhi_cntrl->read_reg ||
915 	    !mhi_cntrl->write_reg || !mhi_cntrl->nr_irqs ||
916 	    !mhi_cntrl->irq || !mhi_cntrl->reg_len)
917 		return -EINVAL;
918 
919 	ret = parse_config(mhi_cntrl, config);
920 	if (ret)
921 		return -EINVAL;
922 
923 	mhi_cntrl->mhi_cmd = kcalloc(NR_OF_CMD_RINGS,
924 				     sizeof(*mhi_cntrl->mhi_cmd), GFP_KERNEL);
925 	if (!mhi_cntrl->mhi_cmd) {
926 		ret = -ENOMEM;
927 		goto err_free_event;
928 	}
929 
930 	INIT_LIST_HEAD(&mhi_cntrl->transition_list);
931 	mutex_init(&mhi_cntrl->pm_mutex);
932 	rwlock_init(&mhi_cntrl->pm_lock);
933 	spin_lock_init(&mhi_cntrl->transition_lock);
934 	spin_lock_init(&mhi_cntrl->wlock);
935 	INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
936 	init_waitqueue_head(&mhi_cntrl->state_event);
937 
938 	mhi_cntrl->hiprio_wq = alloc_ordered_workqueue("mhi_hiprio_wq", WQ_HIGHPRI);
939 	if (!mhi_cntrl->hiprio_wq) {
940 		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate workqueue\n");
941 		ret = -ENOMEM;
942 		goto err_free_cmd;
943 	}
944 
945 	mhi_cmd = mhi_cntrl->mhi_cmd;
946 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++)
947 		spin_lock_init(&mhi_cmd->lock);
948 
949 	mhi_event = mhi_cntrl->mhi_event;
950 	for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) {
951 		/* Skip for offload events */
952 		if (mhi_event->offload_ev)
953 			continue;
954 
955 		mhi_event->mhi_cntrl = mhi_cntrl;
956 		spin_lock_init(&mhi_event->lock);
957 		if (mhi_event->data_type == MHI_ER_CTRL)
958 			tasklet_init(&mhi_event->task, mhi_ctrl_ev_task,
959 				     (ulong)mhi_event);
960 		else
961 			tasklet_init(&mhi_event->task, mhi_ev_task,
962 				     (ulong)mhi_event);
963 	}
964 
965 	mhi_chan = mhi_cntrl->mhi_chan;
966 	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
967 		mutex_init(&mhi_chan->mutex);
968 		init_completion(&mhi_chan->completion);
969 		rwlock_init(&mhi_chan->lock);
970 
971 		/* used in setting bei field of TRE */
972 		mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index];
973 		mhi_chan->intmod = mhi_event->intmod;
974 	}
975 
976 	if (mhi_cntrl->bounce_buf) {
977 		mhi_cntrl->map_single = mhi_map_single_use_bb;
978 		mhi_cntrl->unmap_single = mhi_unmap_single_use_bb;
979 	} else {
980 		mhi_cntrl->map_single = mhi_map_single_no_bb;
981 		mhi_cntrl->unmap_single = mhi_unmap_single_no_bb;
982 	}
983 
984 	/* Read the MHI device info */
985 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs,
986 			   SOC_HW_VERSION_OFFS, &soc_info);
987 	if (ret)
988 		goto err_destroy_wq;
989 
990 	mhi_cntrl->family_number = FIELD_GET(SOC_HW_VERSION_FAM_NUM_BMSK, soc_info);
991 	mhi_cntrl->device_number = FIELD_GET(SOC_HW_VERSION_DEV_NUM_BMSK, soc_info);
992 	mhi_cntrl->major_version = FIELD_GET(SOC_HW_VERSION_MAJOR_VER_BMSK, soc_info);
993 	mhi_cntrl->minor_version = FIELD_GET(SOC_HW_VERSION_MINOR_VER_BMSK, soc_info);
994 
995 	mhi_cntrl->index = ida_alloc(&mhi_controller_ida, GFP_KERNEL);
996 	if (mhi_cntrl->index < 0) {
997 		ret = mhi_cntrl->index;
998 		goto err_destroy_wq;
999 	}
1000 
1001 	ret = mhi_init_irq_setup(mhi_cntrl);
1002 	if (ret)
1003 		goto err_ida_free;
1004 
1005 	/* Register controller with MHI bus */
1006 	mhi_dev = mhi_alloc_device(mhi_cntrl);
1007 	if (IS_ERR(mhi_dev)) {
1008 		dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate MHI device\n");
1009 		ret = PTR_ERR(mhi_dev);
1010 		goto error_setup_irq;
1011 	}
1012 
1013 	mhi_dev->dev_type = MHI_DEVICE_CONTROLLER;
1014 	mhi_dev->mhi_cntrl = mhi_cntrl;
1015 	dev_set_name(&mhi_dev->dev, "mhi%d", mhi_cntrl->index);
1016 	mhi_dev->name = dev_name(&mhi_dev->dev);
1017 
1018 	/* Init wakeup source */
1019 	device_init_wakeup(&mhi_dev->dev, true);
1020 
1021 	ret = device_add(&mhi_dev->dev);
1022 	if (ret)
1023 		goto err_release_dev;
1024 
1025 	mhi_cntrl->mhi_dev = mhi_dev;
1026 
1027 	mhi_create_debugfs(mhi_cntrl);
1028 
1029 	return 0;
1030 
1031 err_release_dev:
1032 	put_device(&mhi_dev->dev);
1033 error_setup_irq:
1034 	mhi_deinit_free_irq(mhi_cntrl);
1035 err_ida_free:
1036 	ida_free(&mhi_controller_ida, mhi_cntrl->index);
1037 err_destroy_wq:
1038 	destroy_workqueue(mhi_cntrl->hiprio_wq);
1039 err_free_cmd:
1040 	kfree(mhi_cntrl->mhi_cmd);
1041 err_free_event:
1042 	kfree(mhi_cntrl->mhi_event);
1043 	vfree(mhi_cntrl->mhi_chan);
1044 
1045 	return ret;
1046 }
1047 EXPORT_SYMBOL_GPL(mhi_register_controller);
1048 
mhi_unregister_controller(struct mhi_controller * mhi_cntrl)1049 void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
1050 {
1051 	struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
1052 	struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan;
1053 	unsigned int i;
1054 
1055 	mhi_deinit_free_irq(mhi_cntrl);
1056 	mhi_destroy_debugfs(mhi_cntrl);
1057 
1058 	destroy_workqueue(mhi_cntrl->hiprio_wq);
1059 	kfree(mhi_cntrl->mhi_cmd);
1060 	kfree(mhi_cntrl->mhi_event);
1061 
1062 	/* Drop the references to MHI devices created for channels */
1063 	for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) {
1064 		if (!mhi_chan->mhi_dev)
1065 			continue;
1066 
1067 		put_device(&mhi_chan->mhi_dev->dev);
1068 	}
1069 	vfree(mhi_cntrl->mhi_chan);
1070 
1071 	device_del(&mhi_dev->dev);
1072 	put_device(&mhi_dev->dev);
1073 
1074 	ida_free(&mhi_controller_ida, mhi_cntrl->index);
1075 }
1076 EXPORT_SYMBOL_GPL(mhi_unregister_controller);
1077 
mhi_alloc_controller(void)1078 struct mhi_controller *mhi_alloc_controller(void)
1079 {
1080 	struct mhi_controller *mhi_cntrl;
1081 
1082 	mhi_cntrl = kzalloc(sizeof(*mhi_cntrl), GFP_KERNEL);
1083 
1084 	return mhi_cntrl;
1085 }
1086 EXPORT_SYMBOL_GPL(mhi_alloc_controller);
1087 
mhi_free_controller(struct mhi_controller * mhi_cntrl)1088 void mhi_free_controller(struct mhi_controller *mhi_cntrl)
1089 {
1090 	kfree(mhi_cntrl);
1091 }
1092 EXPORT_SYMBOL_GPL(mhi_free_controller);
1093 
mhi_prepare_for_power_up(struct mhi_controller * mhi_cntrl)1094 int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
1095 {
1096 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
1097 	u32 bhi_off, bhie_off;
1098 	int ret;
1099 
1100 	mutex_lock(&mhi_cntrl->pm_mutex);
1101 
1102 	ret = mhi_init_dev_ctxt(mhi_cntrl);
1103 	if (ret)
1104 		goto error_dev_ctxt;
1105 
1106 	ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIOFF, &bhi_off);
1107 	if (ret) {
1108 		dev_err(dev, "Error getting BHI offset\n");
1109 		goto error_reg_offset;
1110 	}
1111 
1112 	if (bhi_off >= mhi_cntrl->reg_len) {
1113 		dev_err(dev, "BHI offset: 0x%x is out of range: 0x%zx\n",
1114 			bhi_off, mhi_cntrl->reg_len);
1115 		ret = -EINVAL;
1116 		goto error_reg_offset;
1117 	}
1118 	mhi_cntrl->bhi = mhi_cntrl->regs + bhi_off;
1119 
1120 	if (mhi_cntrl->fbc_download || mhi_cntrl->rddm_size) {
1121 		ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->regs, BHIEOFF,
1122 				   &bhie_off);
1123 		if (ret) {
1124 			dev_err(dev, "Error getting BHIE offset\n");
1125 			goto error_reg_offset;
1126 		}
1127 
1128 		if (bhie_off >= mhi_cntrl->reg_len) {
1129 			dev_err(dev,
1130 				"BHIe offset: 0x%x is out of range: 0x%zx\n",
1131 				bhie_off, mhi_cntrl->reg_len);
1132 			ret = -EINVAL;
1133 			goto error_reg_offset;
1134 		}
1135 		mhi_cntrl->bhie = mhi_cntrl->regs + bhie_off;
1136 	}
1137 
1138 	if (mhi_cntrl->rddm_size) {
1139 		/*
1140 		 * This controller supports RDDM, so we need to manually clear
1141 		 * BHIE RX registers since POR values are undefined.
1142 		 */
1143 		memset_io(mhi_cntrl->bhie + BHIE_RXVECADDR_LOW_OFFS,
1144 			  0, BHIE_RXVECSTATUS_OFFS - BHIE_RXVECADDR_LOW_OFFS +
1145 			  4);
1146 		/*
1147 		 * Allocate RDDM table for debugging purpose if specified
1148 		 */
1149 		mhi_alloc_bhie_table(mhi_cntrl, &mhi_cntrl->rddm_image,
1150 				     mhi_cntrl->rddm_size);
1151 		if (mhi_cntrl->rddm_image) {
1152 			ret = mhi_rddm_prepare(mhi_cntrl,
1153 					       mhi_cntrl->rddm_image);
1154 			if (ret) {
1155 				mhi_free_bhie_table(mhi_cntrl,
1156 						    mhi_cntrl->rddm_image);
1157 				goto error_reg_offset;
1158 			}
1159 		}
1160 	}
1161 
1162 	mutex_unlock(&mhi_cntrl->pm_mutex);
1163 
1164 	return 0;
1165 
1166 error_reg_offset:
1167 	mhi_deinit_dev_ctxt(mhi_cntrl);
1168 
1169 error_dev_ctxt:
1170 	mutex_unlock(&mhi_cntrl->pm_mutex);
1171 
1172 	return ret;
1173 }
1174 EXPORT_SYMBOL_GPL(mhi_prepare_for_power_up);
1175 
mhi_unprepare_after_power_down(struct mhi_controller * mhi_cntrl)1176 void mhi_unprepare_after_power_down(struct mhi_controller *mhi_cntrl)
1177 {
1178 	if (mhi_cntrl->fbc_image) {
1179 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
1180 		mhi_cntrl->fbc_image = NULL;
1181 	}
1182 
1183 	if (mhi_cntrl->rddm_image) {
1184 		mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->rddm_image);
1185 		mhi_cntrl->rddm_image = NULL;
1186 	}
1187 
1188 	mhi_cntrl->bhi = NULL;
1189 	mhi_cntrl->bhie = NULL;
1190 
1191 	mhi_deinit_dev_ctxt(mhi_cntrl);
1192 }
1193 EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
1194 
mhi_release_device(struct device * dev)1195 static void mhi_release_device(struct device *dev)
1196 {
1197 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1198 
1199 	/*
1200 	 * We need to set the mhi_chan->mhi_dev to NULL here since the MHI
1201 	 * devices for the channels will only get created if the mhi_dev
1202 	 * associated with it is NULL. This scenario will happen during the
1203 	 * controller suspend and resume.
1204 	 */
1205 	if (mhi_dev->ul_chan)
1206 		mhi_dev->ul_chan->mhi_dev = NULL;
1207 
1208 	if (mhi_dev->dl_chan)
1209 		mhi_dev->dl_chan->mhi_dev = NULL;
1210 
1211 	kfree(mhi_dev);
1212 }
1213 
mhi_alloc_device(struct mhi_controller * mhi_cntrl)1214 struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl)
1215 {
1216 	struct mhi_device *mhi_dev;
1217 	struct device *dev;
1218 
1219 	mhi_dev = kzalloc(sizeof(*mhi_dev), GFP_KERNEL);
1220 	if (!mhi_dev)
1221 		return ERR_PTR(-ENOMEM);
1222 
1223 	dev = &mhi_dev->dev;
1224 	device_initialize(dev);
1225 	dev->bus = &mhi_bus_type;
1226 	dev->release = mhi_release_device;
1227 
1228 	if (mhi_cntrl->mhi_dev) {
1229 		/* for MHI client devices, parent is the MHI controller device */
1230 		dev->parent = &mhi_cntrl->mhi_dev->dev;
1231 	} else {
1232 		/* for MHI controller device, parent is the bus device (e.g. pci device) */
1233 		dev->parent = mhi_cntrl->cntrl_dev;
1234 	}
1235 
1236 	mhi_dev->mhi_cntrl = mhi_cntrl;
1237 	mhi_dev->dev_wake = 0;
1238 
1239 	return mhi_dev;
1240 }
1241 
mhi_driver_probe(struct device * dev)1242 static int mhi_driver_probe(struct device *dev)
1243 {
1244 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1245 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
1246 	struct device_driver *drv = dev->driver;
1247 	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
1248 	struct mhi_event *mhi_event;
1249 	struct mhi_chan *ul_chan = mhi_dev->ul_chan;
1250 	struct mhi_chan *dl_chan = mhi_dev->dl_chan;
1251 	int ret;
1252 
1253 	/* Bring device out of LPM */
1254 	ret = mhi_device_get_sync(mhi_dev);
1255 	if (ret)
1256 		return ret;
1257 
1258 	ret = -EINVAL;
1259 
1260 	if (ul_chan) {
1261 		/*
1262 		 * If channel supports LPM notifications then status_cb should
1263 		 * be provided
1264 		 */
1265 		if (ul_chan->lpm_notify && !mhi_drv->status_cb)
1266 			goto exit_probe;
1267 
1268 		/* For non-offload channels then xfer_cb should be provided */
1269 		if (!ul_chan->offload_ch && !mhi_drv->ul_xfer_cb)
1270 			goto exit_probe;
1271 
1272 		ul_chan->xfer_cb = mhi_drv->ul_xfer_cb;
1273 	}
1274 
1275 	ret = -EINVAL;
1276 	if (dl_chan) {
1277 		/*
1278 		 * If channel supports LPM notifications then status_cb should
1279 		 * be provided
1280 		 */
1281 		if (dl_chan->lpm_notify && !mhi_drv->status_cb)
1282 			goto exit_probe;
1283 
1284 		/* For non-offload channels then xfer_cb should be provided */
1285 		if (!dl_chan->offload_ch && !mhi_drv->dl_xfer_cb)
1286 			goto exit_probe;
1287 
1288 		mhi_event = &mhi_cntrl->mhi_event[dl_chan->er_index];
1289 
1290 		/*
1291 		 * If the channel event ring is managed by client, then
1292 		 * status_cb must be provided so that the framework can
1293 		 * notify pending data
1294 		 */
1295 		if (mhi_event->cl_manage && !mhi_drv->status_cb)
1296 			goto exit_probe;
1297 
1298 		dl_chan->xfer_cb = mhi_drv->dl_xfer_cb;
1299 	}
1300 
1301 	/* Call the user provided probe function */
1302 	ret = mhi_drv->probe(mhi_dev, mhi_dev->id);
1303 	if (ret)
1304 		goto exit_probe;
1305 
1306 	mhi_device_put(mhi_dev);
1307 
1308 	return ret;
1309 
1310 exit_probe:
1311 	mhi_unprepare_from_transfer(mhi_dev);
1312 
1313 	mhi_device_put(mhi_dev);
1314 
1315 	return ret;
1316 }
1317 
mhi_driver_remove(struct device * dev)1318 static int mhi_driver_remove(struct device *dev)
1319 {
1320 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1321 	struct mhi_driver *mhi_drv = to_mhi_driver(dev->driver);
1322 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
1323 	struct mhi_chan *mhi_chan;
1324 	enum mhi_ch_state ch_state[] = {
1325 		MHI_CH_STATE_DISABLED,
1326 		MHI_CH_STATE_DISABLED
1327 	};
1328 	int dir;
1329 
1330 	/* Skip if it is a controller device */
1331 	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
1332 		return 0;
1333 
1334 	/* Reset both channels */
1335 	for (dir = 0; dir < 2; dir++) {
1336 		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
1337 
1338 		if (!mhi_chan)
1339 			continue;
1340 
1341 		/* Wake all threads waiting for completion */
1342 		write_lock_irq(&mhi_chan->lock);
1343 		mhi_chan->ccs = MHI_EV_CC_INVALID;
1344 		complete_all(&mhi_chan->completion);
1345 		write_unlock_irq(&mhi_chan->lock);
1346 
1347 		/* Set the channel state to disabled */
1348 		mutex_lock(&mhi_chan->mutex);
1349 		write_lock_irq(&mhi_chan->lock);
1350 		ch_state[dir] = mhi_chan->ch_state;
1351 		mhi_chan->ch_state = MHI_CH_STATE_SUSPENDED;
1352 		write_unlock_irq(&mhi_chan->lock);
1353 
1354 		/* Reset the non-offload channel */
1355 		if (!mhi_chan->offload_ch)
1356 			mhi_reset_chan(mhi_cntrl, mhi_chan);
1357 
1358 		mutex_unlock(&mhi_chan->mutex);
1359 	}
1360 
1361 	mhi_drv->remove(mhi_dev);
1362 
1363 	/* De-init channel if it was enabled */
1364 	for (dir = 0; dir < 2; dir++) {
1365 		mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan;
1366 
1367 		if (!mhi_chan)
1368 			continue;
1369 
1370 		mutex_lock(&mhi_chan->mutex);
1371 
1372 		if ((ch_state[dir] == MHI_CH_STATE_ENABLED ||
1373 		     ch_state[dir] == MHI_CH_STATE_STOP) &&
1374 		    !mhi_chan->offload_ch)
1375 			mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
1376 
1377 		mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
1378 
1379 		mutex_unlock(&mhi_chan->mutex);
1380 	}
1381 
1382 	while (mhi_dev->dev_wake)
1383 		mhi_device_put(mhi_dev);
1384 
1385 	return 0;
1386 }
1387 
__mhi_driver_register(struct mhi_driver * mhi_drv,struct module * owner)1388 int __mhi_driver_register(struct mhi_driver *mhi_drv, struct module *owner)
1389 {
1390 	struct device_driver *driver = &mhi_drv->driver;
1391 
1392 	if (!mhi_drv->probe || !mhi_drv->remove)
1393 		return -EINVAL;
1394 
1395 	driver->bus = &mhi_bus_type;
1396 	driver->owner = owner;
1397 	driver->probe = mhi_driver_probe;
1398 	driver->remove = mhi_driver_remove;
1399 
1400 	return driver_register(driver);
1401 }
1402 EXPORT_SYMBOL_GPL(__mhi_driver_register);
1403 
mhi_driver_unregister(struct mhi_driver * mhi_drv)1404 void mhi_driver_unregister(struct mhi_driver *mhi_drv)
1405 {
1406 	driver_unregister(&mhi_drv->driver);
1407 }
1408 EXPORT_SYMBOL_GPL(mhi_driver_unregister);
1409 
mhi_uevent(struct device * dev,struct kobj_uevent_env * env)1410 static int mhi_uevent(struct device *dev, struct kobj_uevent_env *env)
1411 {
1412 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1413 
1414 	return add_uevent_var(env, "MODALIAS=" MHI_DEVICE_MODALIAS_FMT,
1415 					mhi_dev->name);
1416 }
1417 
mhi_match(struct device * dev,struct device_driver * drv)1418 static int mhi_match(struct device *dev, struct device_driver *drv)
1419 {
1420 	struct mhi_device *mhi_dev = to_mhi_device(dev);
1421 	struct mhi_driver *mhi_drv = to_mhi_driver(drv);
1422 	const struct mhi_device_id *id;
1423 
1424 	/*
1425 	 * If the device is a controller type then there is no client driver
1426 	 * associated with it
1427 	 */
1428 	if (mhi_dev->dev_type == MHI_DEVICE_CONTROLLER)
1429 		return 0;
1430 
1431 	for (id = mhi_drv->id_table; id->chan[0]; id++)
1432 		if (!strcmp(mhi_dev->name, id->chan)) {
1433 			mhi_dev->id = id;
1434 			return 1;
1435 		}
1436 
1437 	return 0;
1438 };
1439 
1440 struct bus_type mhi_bus_type = {
1441 	.name = "mhi",
1442 	.dev_name = "mhi",
1443 	.match = mhi_match,
1444 	.uevent = mhi_uevent,
1445 	.dev_groups = mhi_dev_groups,
1446 };
1447 
mhi_init(void)1448 static int __init mhi_init(void)
1449 {
1450 	mhi_debugfs_init();
1451 	return bus_register(&mhi_bus_type);
1452 }
1453 
mhi_exit(void)1454 static void __exit mhi_exit(void)
1455 {
1456 	mhi_debugfs_exit();
1457 	bus_unregister(&mhi_bus_type);
1458 }
1459 
1460 postcore_initcall(mhi_init);
1461 module_exit(mhi_exit);
1462 
1463 MODULE_LICENSE("GPL v2");
1464 MODULE_DESCRIPTION("MHI Host Interface");
1465