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 	return IRQ_HANDLED;
212 }
213 
214 static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
215 {
216 	struct wil6210_priv *wil = cookie;
217 	u32 isr = wil_ioread32_and_clear(wil->csr +
218 					 HOSTADDR(RGF_DMA_EP_TX_ICR) +
219 					 offsetof(struct RGF_ICR, ICR));
220 
221 	trace_wil6210_irq_tx(isr);
222 	wil_dbg_irq(wil, "ISR TX 0x%08x\n", isr);
223 
224 	if (!isr) {
225 		wil_err(wil, "spurious IRQ: TX\n");
226 		return IRQ_NONE;
227 	}
228 
229 	wil6210_mask_irq_tx(wil);
230 
231 	if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
232 		wil_dbg_irq(wil, "TX done\n");
233 		isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
234 		/* clear also all VRING interrupts */
235 		isr &= ~(BIT(25) - 1UL);
236 		if (test_bit(wil_status_reset_done, &wil->status)) {
237 			wil_dbg_txrx(wil, "NAPI(Tx) schedule\n");
238 			napi_schedule(&wil->napi_tx);
239 		} else {
240 			wil_err(wil, "Got Tx interrupt while in reset\n");
241 		}
242 	}
243 
244 	if (isr)
245 		wil_err(wil, "un-handled TX ISR bits 0x%08x\n", isr);
246 
247 	/* Tx IRQ will be enabled when NAPI processing finished */
248 
249 	return IRQ_HANDLED;
250 }
251 
252 static void wil_notify_fw_error(struct wil6210_priv *wil)
253 {
254 	struct device *dev = &wil_to_ndev(wil)->dev;
255 	char *envp[3] = {
256 		[0] = "SOURCE=wil6210",
257 		[1] = "EVENT=FW_ERROR",
258 		[2] = NULL,
259 	};
260 	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
261 }
262 
263 static void wil_cache_mbox_regs(struct wil6210_priv *wil)
264 {
265 	/* make shadow copy of registers that should not change on run time */
266 	wil_memcpy_fromio_32(&wil->mbox_ctl, wil->csr + HOST_MBOX,
267 			     sizeof(struct wil6210_mbox_ctl));
268 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.rx);
269 	wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx);
270 }
271 
272 static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
273 {
274 	struct wil6210_priv *wil = cookie;
275 	u32 isr = wil_ioread32_and_clear(wil->csr +
276 					 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
277 					 offsetof(struct RGF_ICR, ICR));
278 
279 	trace_wil6210_irq_misc(isr);
280 	wil_dbg_irq(wil, "ISR MISC 0x%08x\n", isr);
281 
282 	if (!isr) {
283 		wil_err(wil, "spurious IRQ: MISC\n");
284 		return IRQ_NONE;
285 	}
286 
287 	wil6210_mask_irq_misc(wil);
288 
289 	if (isr & ISR_MISC_FW_ERROR) {
290 		wil_err(wil, "Firmware error detected\n");
291 		clear_bit(wil_status_fwready, &wil->status);
292 		/*
293 		 * do not clear @isr here - we do 2-nd part in thread
294 		 * there, user space get notified, and it should be done
295 		 * in non-atomic context
296 		 */
297 	}
298 
299 	if (isr & ISR_MISC_FW_READY) {
300 		wil_dbg_irq(wil, "IRQ: FW ready\n");
301 		wil_cache_mbox_regs(wil);
302 		set_bit(wil_status_reset_done, &wil->status);
303 		/**
304 		 * Actual FW ready indicated by the
305 		 * WMI_FW_READY_EVENTID
306 		 */
307 		isr &= ~ISR_MISC_FW_READY;
308 	}
309 
310 	wil->isr_misc = isr;
311 
312 	if (isr) {
313 		return IRQ_WAKE_THREAD;
314 	} else {
315 		wil6210_unmask_irq_misc(wil);
316 		return IRQ_HANDLED;
317 	}
318 }
319 
320 static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
321 {
322 	struct wil6210_priv *wil = cookie;
323 	u32 isr = wil->isr_misc;
324 
325 	trace_wil6210_irq_misc_thread(isr);
326 	wil_dbg_irq(wil, "Thread ISR MISC 0x%08x\n", isr);
327 
328 	if (isr & ISR_MISC_FW_ERROR) {
329 		wil_notify_fw_error(wil);
330 		isr &= ~ISR_MISC_FW_ERROR;
331 		wil_fw_error_recovery(wil);
332 	}
333 
334 	if (isr & ISR_MISC_MBOX_EVT) {
335 		wil_dbg_irq(wil, "MBOX event\n");
336 		wmi_recv_cmd(wil);
337 		isr &= ~ISR_MISC_MBOX_EVT;
338 	}
339 
340 	if (isr)
341 		wil_err(wil, "un-handled MISC ISR bits 0x%08x\n", isr);
342 
343 	wil->isr_misc = 0;
344 
345 	wil6210_unmask_irq_misc(wil);
346 
347 	return IRQ_HANDLED;
348 }
349 
350 /**
351  * thread IRQ handler
352  */
353 static irqreturn_t wil6210_thread_irq(int irq, void *cookie)
354 {
355 	struct wil6210_priv *wil = cookie;
356 
357 	wil_dbg_irq(wil, "Thread IRQ\n");
358 	/* Discover real IRQ cause */
359 	if (wil->isr_misc)
360 		wil6210_irq_misc_thread(irq, cookie);
361 
362 	wil6210_unmask_irq_pseudo(wil);
363 
364 	return IRQ_HANDLED;
365 }
366 
367 /* DEBUG
368  * There is subtle bug in hardware that causes IRQ to raise when it should be
369  * masked. It is quite rare and hard to debug.
370  *
371  * Catch irq issue if it happens and print all I can.
372  */
373 static int wil6210_debug_irq_mask(struct wil6210_priv *wil, u32 pseudo_cause)
374 {
375 	if (!test_bit(wil_status_irqen, &wil->status)) {
376 		u32 icm_rx = wil_ioread32_and_clear(wil->csr +
377 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
378 				offsetof(struct RGF_ICR, ICM));
379 		u32 icr_rx = wil_ioread32_and_clear(wil->csr +
380 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
381 				offsetof(struct RGF_ICR, ICR));
382 		u32 imv_rx = ioread32(wil->csr +
383 				HOSTADDR(RGF_DMA_EP_RX_ICR) +
384 				offsetof(struct RGF_ICR, IMV));
385 		u32 icm_tx = wil_ioread32_and_clear(wil->csr +
386 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
387 				offsetof(struct RGF_ICR, ICM));
388 		u32 icr_tx = wil_ioread32_and_clear(wil->csr +
389 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
390 				offsetof(struct RGF_ICR, ICR));
391 		u32 imv_tx = ioread32(wil->csr +
392 				HOSTADDR(RGF_DMA_EP_TX_ICR) +
393 				offsetof(struct RGF_ICR, IMV));
394 		u32 icm_misc = wil_ioread32_and_clear(wil->csr +
395 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
396 				offsetof(struct RGF_ICR, ICM));
397 		u32 icr_misc = wil_ioread32_and_clear(wil->csr +
398 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
399 				offsetof(struct RGF_ICR, ICR));
400 		u32 imv_misc = ioread32(wil->csr +
401 				HOSTADDR(RGF_DMA_EP_MISC_ICR) +
402 				offsetof(struct RGF_ICR, IMV));
403 		wil_err(wil, "IRQ when it should be masked: pseudo 0x%08x\n"
404 				"Rx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
405 				"Tx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
406 				"Misc icm:icr:imv 0x%08x 0x%08x 0x%08x\n",
407 				pseudo_cause,
408 				icm_rx, icr_rx, imv_rx,
409 				icm_tx, icr_tx, imv_tx,
410 				icm_misc, icr_misc, imv_misc);
411 
412 		return -EINVAL;
413 	}
414 
415 	return 0;
416 }
417 
418 static irqreturn_t wil6210_hardirq(int irq, void *cookie)
419 {
420 	irqreturn_t rc = IRQ_HANDLED;
421 	struct wil6210_priv *wil = cookie;
422 	u32 pseudo_cause = ioread32(wil->csr + HOSTADDR(RGF_DMA_PSEUDO_CAUSE));
423 
424 	/**
425 	 * pseudo_cause is Clear-On-Read, no need to ACK
426 	 */
427 	if ((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff))
428 		return IRQ_NONE;
429 
430 	/* FIXME: IRQ mask debug */
431 	if (wil6210_debug_irq_mask(wil, pseudo_cause))
432 		return IRQ_NONE;
433 
434 	trace_wil6210_irq_pseudo(pseudo_cause);
435 	wil_dbg_irq(wil, "Pseudo IRQ 0x%08x\n", pseudo_cause);
436 
437 	wil6210_mask_irq_pseudo(wil);
438 
439 	/* Discover real IRQ cause
440 	 * There are 2 possible phases for every IRQ:
441 	 * - hard IRQ handler called right here
442 	 * - threaded handler called later
443 	 *
444 	 * Hard IRQ handler reads and clears ISR.
445 	 *
446 	 * If threaded handler requested, hard IRQ handler
447 	 * returns IRQ_WAKE_THREAD and saves ISR register value
448 	 * for the threaded handler use.
449 	 *
450 	 * voting for wake thread - need at least 1 vote
451 	 */
452 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_RX) &&
453 	    (wil6210_irq_rx(irq, cookie) == IRQ_WAKE_THREAD))
454 		rc = IRQ_WAKE_THREAD;
455 
456 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_TX) &&
457 	    (wil6210_irq_tx(irq, cookie) == IRQ_WAKE_THREAD))
458 		rc = IRQ_WAKE_THREAD;
459 
460 	if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_MISC) &&
461 	    (wil6210_irq_misc(irq, cookie) == IRQ_WAKE_THREAD))
462 		rc = IRQ_WAKE_THREAD;
463 
464 	/* if thread is requested, it will unmask IRQ */
465 	if (rc != IRQ_WAKE_THREAD)
466 		wil6210_unmask_irq_pseudo(wil);
467 
468 	return rc;
469 }
470 
471 static int wil6210_request_3msi(struct wil6210_priv *wil, int irq)
472 {
473 	int rc;
474 	/*
475 	 * IRQ's are in the following order:
476 	 * - Tx
477 	 * - Rx
478 	 * - Misc
479 	 */
480 
481 	rc = request_irq(irq, wil6210_irq_tx, IRQF_SHARED,
482 			 WIL_NAME"_tx", wil);
483 	if (rc)
484 		return rc;
485 
486 	rc = request_irq(irq + 1, wil6210_irq_rx, IRQF_SHARED,
487 			 WIL_NAME"_rx", wil);
488 	if (rc)
489 		goto free0;
490 
491 	rc = request_threaded_irq(irq + 2, wil6210_irq_misc,
492 				  wil6210_irq_misc_thread,
493 				  IRQF_SHARED, WIL_NAME"_misc", wil);
494 	if (rc)
495 		goto free1;
496 
497 	return 0;
498 	/* error branch */
499 free1:
500 	free_irq(irq + 1, wil);
501 free0:
502 	free_irq(irq, wil);
503 
504 	return rc;
505 }
506 /* can't use wil_ioread32_and_clear because ICC value is not ser yet */
507 static inline void wil_clear32(void __iomem *addr)
508 {
509 	u32 x = ioread32(addr);
510 
511 	iowrite32(x, addr);
512 }
513 
514 void wil6210_clear_irq(struct wil6210_priv *wil)
515 {
516 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_RX_ICR) +
517 		    offsetof(struct RGF_ICR, ICR));
518 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_TX_ICR) +
519 		    offsetof(struct RGF_ICR, ICR));
520 	wil_clear32(wil->csr + HOSTADDR(RGF_DMA_EP_MISC_ICR) +
521 		    offsetof(struct RGF_ICR, ICR));
522 }
523 
524 int wil6210_init_irq(struct wil6210_priv *wil, int irq)
525 {
526 	int rc;
527 	if (wil->n_msi == 3)
528 		rc = wil6210_request_3msi(wil, irq);
529 	else
530 		rc = request_threaded_irq(irq, wil6210_hardirq,
531 					  wil6210_thread_irq,
532 					  wil->n_msi ? 0 : IRQF_SHARED,
533 					  WIL_NAME, wil);
534 	if (rc)
535 		return rc;
536 
537 	wil6210_enable_irq(wil);
538 
539 	return 0;
540 }
541 
542 void wil6210_fini_irq(struct wil6210_priv *wil, int irq)
543 {
544 	wil6210_disable_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