1 /*
2  * Copyright (c) 2012-2014 Qualcomm Atheros, Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/interrupt.h>
18 
19 #include "wil6210.h"
20 #include "trace.h"
21 
22 /**
23  * Theory of operation:
24  *
25  * There is ISR pseudo-cause register,
26  * dma_rgf->DMA_RGF.PSEUDO_CAUSE.PSEUDO_CAUSE
27  * Its bits represents OR'ed bits from 3 real ISR registers:
28  * TX, RX, and MISC.
29  *
30  * Registers may be configured to either "write 1 to clear" or
31  * "clear on read" mode
32  *
33  * When handling interrupt, one have to mask/unmask interrupts for the
34  * real ISR registers, or hardware may malfunction.
35  *
36  */
37 
38 #define WIL6210_IRQ_DISABLE	(0xFFFFFFFFUL)
39 #define WIL6210_IMC_RX		BIT_DMA_EP_RX_ICR_RX_DONE
40 #define WIL6210_IMC_TX		(BIT_DMA_EP_TX_ICR_TX_DONE | \
41 				BIT_DMA_EP_TX_ICR_TX_DONE_N(0))
42 #define WIL6210_IMC_MISC	(ISR_MISC_FW_READY | \
43 				 ISR_MISC_MBOX_EVT | \
44 				 ISR_MISC_FW_ERROR)
45 
46 #define WIL6210_IRQ_PSEUDO_MASK (u32)(~(BIT_DMA_PSEUDO_CAUSE_RX | \
47 					BIT_DMA_PSEUDO_CAUSE_TX | \
48 					BIT_DMA_PSEUDO_CAUSE_MISC))
49 
50 #if defined(CONFIG_WIL6210_ISR_COR)
51 /* configure to Clear-On-Read mode */
52 #define WIL_ICR_ICC_VALUE	(0xFFFFFFFFUL)
53 
54 static inline void wil_icr_clear(u32 x, void __iomem *addr)
55 {
56 }
57 #else /* defined(CONFIG_WIL6210_ISR_COR) */
58 /* configure to Write-1-to-Clear mode */
59 #define WIL_ICR_ICC_VALUE	(0UL)
60 
61 static inline void wil_icr_clear(u32 x, void __iomem *addr)
62 {
63 	iowrite32(x, addr);
64 }
65 #endif /* defined(CONFIG_WIL6210_ISR_COR) */
66 
67 static inline u32 wil_ioread32_and_clear(void __iomem *addr)
68 {
69 	u32 x = ioread32(addr);
70 
71 	wil_icr_clear(x, addr);
72 
73 	return x;
74 }
75 
76 static void wil6210_mask_irq_tx(struct wil6210_priv *wil)
77 {
78 	iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
79 		  HOSTADDR(RGF_DMA_EP_TX_ICR) +
80 		  offsetof(struct RGF_ICR, IMS));
81 }
82 
83 static void wil6210_mask_irq_rx(struct wil6210_priv *wil)
84 {
85 	iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
86 		  HOSTADDR(RGF_DMA_EP_RX_ICR) +
87 		  offsetof(struct RGF_ICR, IMS));
88 }
89 
90 static void wil6210_mask_irq_misc(struct wil6210_priv *wil)
91 {
92 	iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
93 		  HOSTADDR(RGF_DMA_EP_MISC_ICR) +
94 		  offsetof(struct RGF_ICR, IMS));
95 }
96 
97 static void wil6210_mask_irq_pseudo(struct wil6210_priv *wil)
98 {
99 	wil_dbg_irq(wil, "%s()\n", __func__);
100 
101 	iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
102 		  HOSTADDR(RGF_DMA_PSEUDO_CAUSE_MASK_SW));
103 
104 	clear_bit(wil_status_irqen, &wil->status);
105 }
106 
107 void wil6210_unmask_irq_tx(struct wil6210_priv *wil)
108 {
109 	iowrite32(WIL6210_IMC_TX, wil->csr +
110 		  HOSTADDR(RGF_DMA_EP_TX_ICR) +
111 		  offsetof(struct RGF_ICR, IMC));
112 }
113 
114 void wil6210_unmask_irq_rx(struct wil6210_priv *wil)
115 {
116 	iowrite32(WIL6210_IMC_RX, wil->csr +
117 		  HOSTADDR(RGF_DMA_EP_RX_ICR) +
118 		  offsetof(struct RGF_ICR, IMC));
119 }
120 
121 static void wil6210_unmask_irq_misc(struct wil6210_priv *wil)
122 {
123 	iowrite32(WIL6210_IMC_MISC, wil->csr +
124 		  HOSTADDR(RGF_DMA_EP_MISC_ICR) +
125 		  offsetof(struct RGF_ICR, IMC));
126 }
127 
128 static void wil6210_unmask_irq_pseudo(struct wil6210_priv *wil)
129 {
130 	wil_dbg_irq(wil, "%s()\n", __func__);
131 
132 	set_bit(wil_status_irqen, &wil->status);
133 
134 	iowrite32(WIL6210_IRQ_PSEUDO_MASK, wil->csr +
135 		  HOSTADDR(RGF_DMA_PSEUDO_CAUSE_MASK_SW));
136 }
137 
138 void wil_mask_irq(struct wil6210_priv *wil)
139 {
140 	wil_dbg_irq(wil, "%s()\n", __func__);
141 
142 	wil6210_mask_irq_tx(wil);
143 	wil6210_mask_irq_rx(wil);
144 	wil6210_mask_irq_misc(wil);
145 	wil6210_mask_irq_pseudo(wil);
146 }
147 
148 void wil_unmask_irq(struct wil6210_priv *wil)
149 {
150 	wil_dbg_irq(wil, "%s()\n", __func__);
151 
152 	iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_RX_ICR) +
153 		  offsetof(struct RGF_ICR, ICC));
154 	iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_TX_ICR) +
155 		  offsetof(struct RGF_ICR, ICC));
156 	iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_MISC_ICR) +
157 		  offsetof(struct RGF_ICR, ICC));
158 
159 	/* interrupt moderation parameters */
160 	wil_set_itr_trsh(wil);
161 
162 	wil6210_unmask_irq_pseudo(wil);
163 	wil6210_unmask_irq_tx(wil);
164 	wil6210_unmask_irq_rx(wil);
165 	wil6210_unmask_irq_misc(wil);
166 }
167 
168 static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
169 {
170 	struct wil6210_priv *wil = cookie;
171 	u32 isr = wil_ioread32_and_clear(wil->csr +
172 					 HOSTADDR(RGF_DMA_EP_RX_ICR) +
173 					 offsetof(struct RGF_ICR, ICR));
174 
175 	trace_wil6210_irq_rx(isr);
176 	wil_dbg_irq(wil, "ISR RX 0x%08x\n", isr);
177 
178 	if (!isr) {
179 		wil_err(wil, "spurious IRQ: RX\n");
180 		return IRQ_NONE;
181 	}
182 
183 	wil6210_mask_irq_rx(wil);
184 
185 	if (isr & BIT_DMA_EP_RX_ICR_RX_DONE) {
186 		wil_dbg_irq(wil, "RX done\n");
187 		isr &= ~BIT_DMA_EP_RX_ICR_RX_DONE;
188 		if (test_bit(wil_status_reset_done, &wil->status)) {
189 			if (test_bit(wil_status_napi_en, &wil->status)) {
190 				wil_dbg_txrx(wil, "NAPI(Rx) schedule\n");
191 				napi_schedule(&wil->napi_rx);
192 			} else {
193 				wil_err(wil, "Got Rx interrupt while "
194 					"stopping interface\n");
195 			}
196 		} else {
197 			wil_err(wil, "Got Rx interrupt while in reset\n");
198 		}
199 	}
200 
201 	if (isr)
202 		wil_err(wil, "un-handled RX ISR bits 0x%08x\n", isr);
203 
204 	/* Rx IRQ will be enabled when NAPI processing finished */
205 
206 	atomic_inc(&wil->isr_count_rx);
207 	return IRQ_HANDLED;
208 }
209 
210 static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
211 {
212 	struct wil6210_priv *wil = cookie;
213 	u32 isr = wil_ioread32_and_clear(wil->csr +
214 					 HOSTADDR(RGF_DMA_EP_TX_ICR) +
215 					 offsetof(struct RGF_ICR, ICR));
216 
217 	trace_wil6210_irq_tx(isr);
218 	wil_dbg_irq(wil, "ISR TX 0x%08x\n", isr);
219 
220 	if (!isr) {
221 		wil_err(wil, "spurious IRQ: TX\n");
222 		return IRQ_NONE;
223 	}
224 
225 	wil6210_mask_irq_tx(wil);
226 
227 	if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
228 		wil_dbg_irq(wil, "TX done\n");
229 		isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
230 		/* clear also all VRING interrupts */
231 		isr &= ~(BIT(25) - 1UL);
232 		if (test_bit(wil_status_reset_done, &wil->status)) {
233 			wil_dbg_txrx(wil, "NAPI(Tx) schedule\n");
234 			napi_schedule(&wil->napi_tx);
235 		} else {
236 			wil_err(wil, "Got Tx interrupt while in reset\n");
237 		}
238 	}
239 
240 	if (isr)
241 		wil_err(wil, "un-handled TX ISR bits 0x%08x\n", isr);
242 
243 	/* Tx IRQ will be enabled when NAPI processing finished */
244 
245 	atomic_inc(&wil->isr_count_tx);
246 	return IRQ_HANDLED;
247 }
248 
249 static void wil_notify_fw_error(struct wil6210_priv *wil)
250 {
251 	struct device *dev = &wil_to_ndev(wil)->dev;
252 	char *envp[3] = {
253 		[0] = "SOURCE=wil6210",
254 		[1] = "EVENT=FW_ERROR",
255 		[2] = NULL,
256 	};
257 	wil_err(wil, "Notify about firmware error\n");
258 	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
259 }
260 
261 static void wil_cache_mbox_regs(struct wil6210_priv *wil)
262 {
263 	/* make shadow copy of registers that should not change on run time */
264 	wil_memcpy_fromio_32(&wil->mbox_ctl, wil->csr + HOST_MBOX,
265 			     sizeof(struct wil6210_mbox_ctl));
266 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.rx);
267 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx);
268 }
269 
270 static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
271 {
272 	struct wil6210_priv *wil = cookie;
273 	u32 isr = wil_ioread32_and_clear(wil->csr +
274 					 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
275 					 offsetof(struct RGF_ICR, ICR));
276 
277 	trace_wil6210_irq_misc(isr);
278 	wil_dbg_irq(wil, "ISR MISC 0x%08x\n", isr);
279 
280 	if (!isr) {
281 		wil_err(wil, "spurious IRQ: MISC\n");
282 		return IRQ_NONE;
283 	}
284 
285 	wil6210_mask_irq_misc(wil);
286 
287 	if (isr & ISR_MISC_FW_ERROR) {
288 		wil_err(wil, "Firmware error detected\n");
289 		clear_bit(wil_status_fwready, &wil->status);
290 		/*
291 		 * do not clear @isr here - we do 2-nd part in thread
292 		 * there, user space get notified, and it should be done
293 		 * in non-atomic context
294 		 */
295 	}
296 
297 	if (isr & ISR_MISC_FW_READY) {
298 		wil_dbg_irq(wil, "IRQ: FW ready\n");
299 		wil_cache_mbox_regs(wil);
300 		set_bit(wil_status_reset_done, &wil->status);
301 		/**
302 		 * Actual FW ready indicated by the
303 		 * WMI_FW_READY_EVENTID
304 		 */
305 		isr &= ~ISR_MISC_FW_READY;
306 	}
307 
308 	wil->isr_misc = isr;
309 
310 	if (isr) {
311 		return IRQ_WAKE_THREAD;
312 	} else {
313 		wil6210_unmask_irq_misc(wil);
314 		return IRQ_HANDLED;
315 	}
316 }
317 
318 static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
319 {
320 	struct wil6210_priv *wil = cookie;
321 	u32 isr = wil->isr_misc;
322 
323 	trace_wil6210_irq_misc_thread(isr);
324 	wil_dbg_irq(wil, "Thread ISR MISC 0x%08x\n", isr);
325 
326 	if (isr & ISR_MISC_FW_ERROR) {
327 		wil_notify_fw_error(wil);
328 		isr &= ~ISR_MISC_FW_ERROR;
329 		wil_fw_error_recovery(wil);
330 	}
331 
332 	if (isr & ISR_MISC_MBOX_EVT) {
333 		wil_dbg_irq(wil, "MBOX event\n");
334 		wmi_recv_cmd(wil);
335 		isr &= ~ISR_MISC_MBOX_EVT;
336 	}
337 
338 	if (isr)
339 		wil_dbg_irq(wil, "un-handled MISC ISR bits 0x%08x\n", isr);
340 
341 	wil->isr_misc = 0;
342 
343 	wil6210_unmask_irq_misc(wil);
344 
345 	return IRQ_HANDLED;
346 }
347 
348 /**
349  * thread IRQ handler
350  */
351 static irqreturn_t wil6210_thread_irq(int irq, void *cookie)
352 {
353 	struct wil6210_priv *wil = cookie;
354 
355 	wil_dbg_irq(wil, "Thread IRQ\n");
356 	/* Discover real IRQ cause */
357 	if (wil->isr_misc)
358 		wil6210_irq_misc_thread(irq, cookie);
359 
360 	wil6210_unmask_irq_pseudo(wil);
361 
362 	return IRQ_HANDLED;
363 }
364 
365 /* DEBUG
366  * There is subtle bug in hardware that causes IRQ to raise when it should be
367  * masked. It is quite rare and hard to debug.
368  *
369  * Catch irq issue if it happens and print all I can.
370  */
371 static int wil6210_debug_irq_mask(struct wil6210_priv *wil, u32 pseudo_cause)
372 {
373 	if (!test_bit(wil_status_irqen, &wil->status)) {
374 		u32 icm_rx = wil_ioread32_and_clear(wil->csr +
375 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
376 				offsetof(struct RGF_ICR, ICM));
377 		u32 icr_rx = wil_ioread32_and_clear(wil->csr +
378 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
379 				offsetof(struct RGF_ICR, ICR));
380 		u32 imv_rx = ioread32(wil->csr +
381 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
382 				offsetof(struct RGF_ICR, IMV));
383 		u32 icm_tx = wil_ioread32_and_clear(wil->csr +
384 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
385 				offsetof(struct RGF_ICR, ICM));
386 		u32 icr_tx = wil_ioread32_and_clear(wil->csr +
387 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
388 				offsetof(struct RGF_ICR, ICR));
389 		u32 imv_tx = ioread32(wil->csr +
390 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
391 				offsetof(struct RGF_ICR, IMV));
392 		u32 icm_misc = wil_ioread32_and_clear(wil->csr +
393 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
394 				offsetof(struct RGF_ICR, ICM));
395 		u32 icr_misc = wil_ioread32_and_clear(wil->csr +
396 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
397 				offsetof(struct RGF_ICR, ICR));
398 		u32 imv_misc = ioread32(wil->csr +
399 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
400 				offsetof(struct RGF_ICR, IMV));
401 		wil_err(wil, "IRQ when it should be masked: pseudo 0x%08x\n"
402 				"Rx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
403 				"Tx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
404 				"Misc icm:icr:imv 0x%08x 0x%08x 0x%08x\n",
405 				pseudo_cause,
406 				icm_rx, icr_rx, imv_rx,
407 				icm_tx, icr_tx, imv_tx,
408 				icm_misc, icr_misc, imv_misc);
409 
410 		return -EINVAL;
411 	}
412 
413 	return 0;
414 }
415 
416 static irqreturn_t wil6210_hardirq(int irq, void *cookie)
417 {
418 	irqreturn_t rc = IRQ_HANDLED;
419 	struct wil6210_priv *wil = cookie;
420 	u32 pseudo_cause = ioread32(wil->csr + HOSTADDR(RGF_DMA_PSEUDO_CAUSE));
421 
422 	/**
423 	 * pseudo_cause is Clear-On-Read, no need to ACK
424 	 */
425 	if ((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff))
426 		return IRQ_NONE;
427 
428 	/* FIXME: IRQ mask debug */
429 	if (wil6210_debug_irq_mask(wil, pseudo_cause))
430 		return IRQ_NONE;
431 
432 	trace_wil6210_irq_pseudo(pseudo_cause);
433 	wil_dbg_irq(wil, "Pseudo IRQ 0x%08x\n", pseudo_cause);
434 
435 	wil6210_mask_irq_pseudo(wil);
436 
437 	/* Discover real IRQ cause
438 	 * There are 2 possible phases for every IRQ:
439 	 * - hard IRQ handler called right here
440 	 * - threaded handler called later
441 	 *
442 	 * Hard IRQ handler reads and clears ISR.
443 	 *
444 	 * If threaded handler requested, hard IRQ handler
445 	 * returns IRQ_WAKE_THREAD and saves ISR register value
446 	 * for the threaded handler use.
447 	 *
448 	 * voting for wake thread - need at least 1 vote
449 	 */
450 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_RX) &&
451 	    (wil6210_irq_rx(irq, cookie) == IRQ_WAKE_THREAD))
452 		rc = IRQ_WAKE_THREAD;
453 
454 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_TX) &&
455 	    (wil6210_irq_tx(irq, cookie) == IRQ_WAKE_THREAD))
456 		rc = IRQ_WAKE_THREAD;
457 
458 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_MISC) &&
459 	    (wil6210_irq_misc(irq, cookie) == IRQ_WAKE_THREAD))
460 		rc = IRQ_WAKE_THREAD;
461 
462 	/* if thread is requested, it will unmask IRQ */
463 	if (rc != IRQ_WAKE_THREAD)
464 		wil6210_unmask_irq_pseudo(wil);
465 
466 	return rc;
467 }
468 
469 static int wil6210_request_3msi(struct wil6210_priv *wil, int irq)
470 {
471 	int rc;
472 	/*
473 	 * IRQ's are in the following order:
474 	 * - Tx
475 	 * - Rx
476 	 * - Misc
477 	 */
478 
479 	rc = request_irq(irq, wil6210_irq_tx, IRQF_SHARED,
480 			 WIL_NAME"_tx", wil);
481 	if (rc)
482 		return rc;
483 
484 	rc = request_irq(irq + 1, wil6210_irq_rx, IRQF_SHARED,
485 			 WIL_NAME"_rx", wil);
486 	if (rc)
487 		goto free0;
488 
489 	rc = request_threaded_irq(irq + 2, wil6210_irq_misc,
490 				  wil6210_irq_misc_thread,
491 				  IRQF_SHARED, WIL_NAME"_misc", wil);
492 	if (rc)
493 		goto free1;
494 
495 	return 0;
496 	/* error branch */
497 free1:
498 	free_irq(irq + 1, wil);
499 free0:
500 	free_irq(irq, wil);
501 
502 	return rc;
503 }
504 
505 /* can't use wil_ioread32_and_clear because ICC value is not set yet */
506 static inline void wil_clear32(void __iomem *addr)
507 {
508 	u32 x = ioread32(addr);
509 
510 	iowrite32(x, addr);
511 }
512 
513 void wil6210_clear_irq(struct wil6210_priv *wil)
514 {
515 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_RX_ICR) +
516 		    offsetof(struct RGF_ICR, ICR));
517 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_TX_ICR) +
518 		    offsetof(struct RGF_ICR, ICR));
519 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_MISC_ICR) +
520 		    offsetof(struct RGF_ICR, ICR));
521 	wmb(); /* make sure write completed */
522 }
523 
524 int wil6210_init_irq(struct wil6210_priv *wil, int irq)
525 {
526 	int rc;
527 
528 	wil_dbg_misc(wil, "%s() n_msi=%d\n", __func__, wil->n_msi);
529 
530 	if (wil->n_msi == 3)
531 		rc = wil6210_request_3msi(wil, irq);
532 	else
533 		rc = request_threaded_irq(irq, wil6210_hardirq,
534 					  wil6210_thread_irq,
535 					  wil->n_msi ? 0 : IRQF_SHARED,
536 					  WIL_NAME, wil);
537 	return rc;
538 }
539 
540 void wil6210_fini_irq(struct wil6210_priv *wil, int irq)
541 {
542 	wil_dbg_misc(wil, "%s()\n", __func__);
543 
544 	wil_mask_irq(wil);
545 	free_irq(irq, wil);
546 	if (wil->n_msi == 3) {
547 		free_irq(irq + 1, wil);
548 		free_irq(irq + 2, wil);
549 	}
550 }
551