1 /*
2  * Copyright (c) 2012 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 wil6210_disable_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 wil6210_enable_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 	if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
161 		/* disable interrupt moderation for monitor
162 		 * to get better timestamp precision
163 		 */
164 		iowrite32(0, wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_CRL));
165 	} else {
166 		iowrite32(WIL6210_ITR_TRSH,
167 			  wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_TRSH));
168 		iowrite32(BIT_DMA_ITR_CNT_CRL_EN,
169 			  wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_CRL));
170 	}
171 
172 	wil6210_unmask_irq_pseudo(wil);
173 	wil6210_unmask_irq_tx(wil);
174 	wil6210_unmask_irq_rx(wil);
175 	wil6210_unmask_irq_misc(wil);
176 }
177 
178 static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
179 {
180 	struct wil6210_priv *wil = cookie;
181 	u32 isr = wil_ioread32_and_clear(wil->csr +
182 					 HOSTADDR(RGF_DMA_EP_RX_ICR) +
183 					 offsetof(struct RGF_ICR, ICR));
184 
185 	trace_wil6210_irq_rx(isr);
186 	wil_dbg_irq(wil, "ISR RX 0x%08x\n", isr);
187 
188 	if (!isr) {
189 		wil_err(wil, "spurious IRQ: RX\n");
190 		return IRQ_NONE;
191 	}
192 
193 	wil6210_mask_irq_rx(wil);
194 
195 	if (isr & BIT_DMA_EP_RX_ICR_RX_DONE) {
196 		wil_dbg_irq(wil, "RX done\n");
197 		isr &= ~BIT_DMA_EP_RX_ICR_RX_DONE;
198 		if (test_bit(wil_status_reset_done, &wil->status)) {
199 			wil_dbg_txrx(wil, "NAPI(Rx) schedule\n");
200 			napi_schedule(&wil->napi_rx);
201 		} else {
202 			wil_err(wil, "Got Rx interrupt while in reset\n");
203 		}
204 	}
205 
206 	if (isr)
207 		wil_err(wil, "un-handled RX ISR bits 0x%08x\n", isr);
208 
209 	/* Rx IRQ will be enabled when NAPI processing finished */
210 
211 	atomic_inc(&wil->isr_count_rx);
212 	return IRQ_HANDLED;
213 }
214 
215 static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
216 {
217 	struct wil6210_priv *wil = cookie;
218 	u32 isr = wil_ioread32_and_clear(wil->csr +
219 					 HOSTADDR(RGF_DMA_EP_TX_ICR) +
220 					 offsetof(struct RGF_ICR, ICR));
221 
222 	trace_wil6210_irq_tx(isr);
223 	wil_dbg_irq(wil, "ISR TX 0x%08x\n", isr);
224 
225 	if (!isr) {
226 		wil_err(wil, "spurious IRQ: TX\n");
227 		return IRQ_NONE;
228 	}
229 
230 	wil6210_mask_irq_tx(wil);
231 
232 	if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
233 		wil_dbg_irq(wil, "TX done\n");
234 		isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
235 		/* clear also all VRING interrupts */
236 		isr &= ~(BIT(25) - 1UL);
237 		if (test_bit(wil_status_reset_done, &wil->status)) {
238 			wil_dbg_txrx(wil, "NAPI(Tx) schedule\n");
239 			napi_schedule(&wil->napi_tx);
240 		} else {
241 			wil_err(wil, "Got Tx interrupt while in reset\n");
242 		}
243 	}
244 
245 	if (isr)
246 		wil_err(wil, "un-handled TX ISR bits 0x%08x\n", isr);
247 
248 	/* Tx IRQ will be enabled when NAPI processing finished */
249 
250 	atomic_inc(&wil->isr_count_tx);
251 	return IRQ_HANDLED;
252 }
253 
254 static void wil_notify_fw_error(struct wil6210_priv *wil)
255 {
256 	struct device *dev = &wil_to_ndev(wil)->dev;
257 	char *envp[3] = {
258 		[0] = "SOURCE=wil6210",
259 		[1] = "EVENT=FW_ERROR",
260 		[2] = NULL,
261 	};
262 	wil_err(wil, "Notify about firmware error\n");
263 	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
264 }
265 
266 static void wil_cache_mbox_regs(struct wil6210_priv *wil)
267 {
268 	/* make shadow copy of registers that should not change on run time */
269 	wil_memcpy_fromio_32(&wil->mbox_ctl, wil->csr + HOST_MBOX,
270 			     sizeof(struct wil6210_mbox_ctl));
271 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.rx);
272 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx);
273 }
274 
275 static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
276 {
277 	struct wil6210_priv *wil = cookie;
278 	u32 isr = wil_ioread32_and_clear(wil->csr +
279 					 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
280 					 offsetof(struct RGF_ICR, ICR));
281 
282 	trace_wil6210_irq_misc(isr);
283 	wil_dbg_irq(wil, "ISR MISC 0x%08x\n", isr);
284 
285 	if (!isr) {
286 		wil_err(wil, "spurious IRQ: MISC\n");
287 		return IRQ_NONE;
288 	}
289 
290 	wil6210_mask_irq_misc(wil);
291 
292 	if (isr & ISR_MISC_FW_ERROR) {
293 		wil_err(wil, "Firmware error detected\n");
294 		clear_bit(wil_status_fwready, &wil->status);
295 		/*
296 		 * do not clear @isr here - we do 2-nd part in thread
297 		 * there, user space get notified, and it should be done
298 		 * in non-atomic context
299 		 */
300 	}
301 
302 	if (isr & ISR_MISC_FW_READY) {
303 		wil_dbg_irq(wil, "IRQ: FW ready\n");
304 		wil_cache_mbox_regs(wil);
305 		set_bit(wil_status_reset_done, &wil->status);
306 		/**
307 		 * Actual FW ready indicated by the
308 		 * WMI_FW_READY_EVENTID
309 		 */
310 		isr &= ~ISR_MISC_FW_READY;
311 	}
312 
313 	wil->isr_misc = isr;
314 
315 	if (isr) {
316 		return IRQ_WAKE_THREAD;
317 	} else {
318 		wil6210_unmask_irq_misc(wil);
319 		return IRQ_HANDLED;
320 	}
321 }
322 
323 static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
324 {
325 	struct wil6210_priv *wil = cookie;
326 	u32 isr = wil->isr_misc;
327 
328 	trace_wil6210_irq_misc_thread(isr);
329 	wil_dbg_irq(wil, "Thread ISR MISC 0x%08x\n", isr);
330 
331 	if (isr & ISR_MISC_FW_ERROR) {
332 		wil_notify_fw_error(wil);
333 		isr &= ~ISR_MISC_FW_ERROR;
334 		wil_fw_error_recovery(wil);
335 	}
336 
337 	if (isr & ISR_MISC_MBOX_EVT) {
338 		wil_dbg_irq(wil, "MBOX event\n");
339 		wmi_recv_cmd(wil);
340 		isr &= ~ISR_MISC_MBOX_EVT;
341 	}
342 
343 	if (isr)
344 		wil_dbg_irq(wil, "un-handled MISC ISR bits 0x%08x\n", isr);
345 
346 	wil->isr_misc = 0;
347 
348 	wil6210_unmask_irq_misc(wil);
349 
350 	return IRQ_HANDLED;
351 }
352 
353 /**
354  * thread IRQ handler
355  */
356 static irqreturn_t wil6210_thread_irq(int irq, void *cookie)
357 {
358 	struct wil6210_priv *wil = cookie;
359 
360 	wil_dbg_irq(wil, "Thread IRQ\n");
361 	/* Discover real IRQ cause */
362 	if (wil->isr_misc)
363 		wil6210_irq_misc_thread(irq, cookie);
364 
365 	wil6210_unmask_irq_pseudo(wil);
366 
367 	return IRQ_HANDLED;
368 }
369 
370 /* DEBUG
371  * There is subtle bug in hardware that causes IRQ to raise when it should be
372  * masked. It is quite rare and hard to debug.
373  *
374  * Catch irq issue if it happens and print all I can.
375  */
376 static int wil6210_debug_irq_mask(struct wil6210_priv *wil, u32 pseudo_cause)
377 {
378 	if (!test_bit(wil_status_irqen, &wil->status)) {
379 		u32 icm_rx = wil_ioread32_and_clear(wil->csr +
380 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
381 				offsetof(struct RGF_ICR, ICM));
382 		u32 icr_rx = wil_ioread32_and_clear(wil->csr +
383 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
384 				offsetof(struct RGF_ICR, ICR));
385 		u32 imv_rx = ioread32(wil->csr +
386 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
387 				offsetof(struct RGF_ICR, IMV));
388 		u32 icm_tx = wil_ioread32_and_clear(wil->csr +
389 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
390 				offsetof(struct RGF_ICR, ICM));
391 		u32 icr_tx = wil_ioread32_and_clear(wil->csr +
392 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
393 				offsetof(struct RGF_ICR, ICR));
394 		u32 imv_tx = ioread32(wil->csr +
395 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
396 				offsetof(struct RGF_ICR, IMV));
397 		u32 icm_misc = wil_ioread32_and_clear(wil->csr +
398 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
399 				offsetof(struct RGF_ICR, ICM));
400 		u32 icr_misc = wil_ioread32_and_clear(wil->csr +
401 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
402 				offsetof(struct RGF_ICR, ICR));
403 		u32 imv_misc = ioread32(wil->csr +
404 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
405 				offsetof(struct RGF_ICR, IMV));
406 		wil_err(wil, "IRQ when it should be masked: pseudo 0x%08x\n"
407 				"Rx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
408 				"Tx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
409 				"Misc icm:icr:imv 0x%08x 0x%08x 0x%08x\n",
410 				pseudo_cause,
411 				icm_rx, icr_rx, imv_rx,
412 				icm_tx, icr_tx, imv_tx,
413 				icm_misc, icr_misc, imv_misc);
414 
415 		return -EINVAL;
416 	}
417 
418 	return 0;
419 }
420 
421 static irqreturn_t wil6210_hardirq(int irq, void *cookie)
422 {
423 	irqreturn_t rc = IRQ_HANDLED;
424 	struct wil6210_priv *wil = cookie;
425 	u32 pseudo_cause = ioread32(wil->csr + HOSTADDR(RGF_DMA_PSEUDO_CAUSE));
426 
427 	/**
428 	 * pseudo_cause is Clear-On-Read, no need to ACK
429 	 */
430 	if ((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff))
431 		return IRQ_NONE;
432 
433 	/* FIXME: IRQ mask debug */
434 	if (wil6210_debug_irq_mask(wil, pseudo_cause))
435 		return IRQ_NONE;
436 
437 	trace_wil6210_irq_pseudo(pseudo_cause);
438 	wil_dbg_irq(wil, "Pseudo IRQ 0x%08x\n", pseudo_cause);
439 
440 	wil6210_mask_irq_pseudo(wil);
441 
442 	/* Discover real IRQ cause
443 	 * There are 2 possible phases for every IRQ:
444 	 * - hard IRQ handler called right here
445 	 * - threaded handler called later
446 	 *
447 	 * Hard IRQ handler reads and clears ISR.
448 	 *
449 	 * If threaded handler requested, hard IRQ handler
450 	 * returns IRQ_WAKE_THREAD and saves ISR register value
451 	 * for the threaded handler use.
452 	 *
453 	 * voting for wake thread - need at least 1 vote
454 	 */
455 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_RX) &&
456 	    (wil6210_irq_rx(irq, cookie) == IRQ_WAKE_THREAD))
457 		rc = IRQ_WAKE_THREAD;
458 
459 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_TX) &&
460 	    (wil6210_irq_tx(irq, cookie) == IRQ_WAKE_THREAD))
461 		rc = IRQ_WAKE_THREAD;
462 
463 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_MISC) &&
464 	    (wil6210_irq_misc(irq, cookie) == IRQ_WAKE_THREAD))
465 		rc = IRQ_WAKE_THREAD;
466 
467 	/* if thread is requested, it will unmask IRQ */
468 	if (rc != IRQ_WAKE_THREAD)
469 		wil6210_unmask_irq_pseudo(wil);
470 
471 	return rc;
472 }
473 
474 static int wil6210_request_3msi(struct wil6210_priv *wil, int irq)
475 {
476 	int rc;
477 	/*
478 	 * IRQ's are in the following order:
479 	 * - Tx
480 	 * - Rx
481 	 * - Misc
482 	 */
483 
484 	rc = request_irq(irq, wil6210_irq_tx, IRQF_SHARED,
485 			 WIL_NAME"_tx", wil);
486 	if (rc)
487 		return rc;
488 
489 	rc = request_irq(irq + 1, wil6210_irq_rx, IRQF_SHARED,
490 			 WIL_NAME"_rx", wil);
491 	if (rc)
492 		goto free0;
493 
494 	rc = request_threaded_irq(irq + 2, wil6210_irq_misc,
495 				  wil6210_irq_misc_thread,
496 				  IRQF_SHARED, WIL_NAME"_misc", wil);
497 	if (rc)
498 		goto free1;
499 
500 	return 0;
501 	/* error branch */
502 free1:
503 	free_irq(irq + 1, wil);
504 free0:
505 	free_irq(irq, wil);
506 
507 	return rc;
508 }
509 /* can't use wil_ioread32_and_clear because ICC value is not ser yet */
510 static inline void wil_clear32(void __iomem *addr)
511 {
512 	u32 x = ioread32(addr);
513 
514 	iowrite32(x, addr);
515 }
516 
517 void wil6210_clear_irq(struct wil6210_priv *wil)
518 {
519 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_RX_ICR) +
520 		    offsetof(struct RGF_ICR, ICR));
521 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_TX_ICR) +
522 		    offsetof(struct RGF_ICR, ICR));
523 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_MISC_ICR) +
524 		    offsetof(struct RGF_ICR, ICR));
525 }
526 
527 int wil6210_init_irq(struct wil6210_priv *wil, int irq)
528 {
529 	int rc;
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 	if (rc)
538 		return rc;
539 
540 	wil6210_enable_irq(wil);
541 
542 	return 0;
543 }
544 
545 void wil6210_fini_irq(struct wil6210_priv *wil, int irq)
546 {
547 	wil6210_disable_irq(wil);
548 	free_irq(irq, wil);
549 	if (wil->n_msi == 3) {
550 		free_irq(irq + 1, wil);
551 		free_irq(irq + 2, wil);
552 	}
553 }
554