1 /**
2  * Copyright (c) 2014 Redpine Signals 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 
18 #include <linux/firmware.h>
19 #include <net/rsi_91x.h>
20 #include "rsi_sdio.h"
21 #include "rsi_common.h"
22 
23 /**
24  * rsi_sdio_master_access_msword() - This function sets the AHB master access
25  *				     MS word in the SDIO slave registers.
26  * @adapter: Pointer to the adapter structure.
27  * @ms_word: ms word need to be initialized.
28  *
29  * Return: status: 0 on success, -1 on failure.
30  */
31 int rsi_sdio_master_access_msword(struct rsi_hw *adapter, u16 ms_word)
32 {
33 	u8 byte;
34 	u8 function = 0;
35 	int status = 0;
36 
37 	byte = (u8)(ms_word & 0x00FF);
38 
39 	rsi_dbg(INIT_ZONE,
40 		"%s: MASTER_ACCESS_MSBYTE:0x%x\n", __func__, byte);
41 
42 	status = rsi_sdio_write_register(adapter,
43 					 function,
44 					 SDIO_MASTER_ACCESS_MSBYTE,
45 					 &byte);
46 	if (status) {
47 		rsi_dbg(ERR_ZONE,
48 			"%s: fail to access MASTER_ACCESS_MSBYTE\n",
49 			__func__);
50 		return -1;
51 	}
52 
53 	byte = (u8)(ms_word >> 8);
54 
55 	rsi_dbg(INIT_ZONE, "%s:MASTER_ACCESS_LSBYTE:0x%x\n", __func__, byte);
56 	status = rsi_sdio_write_register(adapter,
57 					 function,
58 					 SDIO_MASTER_ACCESS_LSBYTE,
59 					 &byte);
60 	return status;
61 }
62 
63 void rsi_sdio_rx_thread(struct rsi_common *common)
64 {
65 	struct rsi_hw *adapter = common->priv;
66 	struct rsi_91x_sdiodev *sdev = adapter->rsi_dev;
67 	struct sk_buff *skb;
68 	int status;
69 
70 	do {
71 		rsi_wait_event(&sdev->rx_thread.event, EVENT_WAIT_FOREVER);
72 		rsi_reset_event(&sdev->rx_thread.event);
73 
74 		while (true) {
75 			if (atomic_read(&sdev->rx_thread.thread_done))
76 				goto out;
77 
78 			skb = skb_dequeue(&sdev->rx_q.head);
79 			if (!skb)
80 				break;
81 			if (sdev->rx_q.num_rx_pkts > 0)
82 				sdev->rx_q.num_rx_pkts--;
83 			status = rsi_read_pkt(common, skb->data, skb->len);
84 			if (status) {
85 				rsi_dbg(ERR_ZONE, "Failed to read the packet\n");
86 				dev_kfree_skb(skb);
87 				break;
88 			}
89 			dev_kfree_skb(skb);
90 		}
91 	} while (1);
92 
93 out:
94 	rsi_dbg(INFO_ZONE, "%s: Terminated SDIO RX thread\n", __func__);
95 	skb_queue_purge(&sdev->rx_q.head);
96 	atomic_inc(&sdev->rx_thread.thread_done);
97 	complete_and_exit(&sdev->rx_thread.completion, 0);
98 }
99 
100 /**
101  * rsi_process_pkt() - This Function reads rx_blocks register and figures out
102  *		       the size of the rx pkt.
103  * @common: Pointer to the driver private structure.
104  *
105  * Return: 0 on success, -1 on failure.
106  */
107 static int rsi_process_pkt(struct rsi_common *common)
108 {
109 	struct rsi_hw *adapter = common->priv;
110 	struct rsi_91x_sdiodev *dev =
111 		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
112 	u8 num_blks = 0;
113 	u32 rcv_pkt_len = 0;
114 	int status = 0;
115 	u8 value = 0;
116 	struct sk_buff *skb;
117 
118 	if (dev->rx_q.num_rx_pkts >= RSI_MAX_RX_PKTS)
119 		return 0;
120 
121 	num_blks = ((adapter->interrupt_status & 1) |
122 			((adapter->interrupt_status >> RECV_NUM_BLOCKS) << 1));
123 
124 	if (!num_blks) {
125 		status = rsi_sdio_read_register(adapter,
126 						SDIO_RX_NUM_BLOCKS_REG,
127 						&value);
128 		if (status) {
129 			rsi_dbg(ERR_ZONE,
130 				"%s: Failed to read pkt length from the card:\n",
131 				__func__);
132 			return status;
133 		}
134 		num_blks = value & 0x1f;
135 	}
136 
137 	if (dev->write_fail == 2)
138 		rsi_sdio_ack_intr(common->priv, (1 << MSDU_PKT_PENDING));
139 
140 	if (unlikely(!num_blks)) {
141 		dev->write_fail = 2;
142 		return -1;
143 	}
144 
145 	rcv_pkt_len = (num_blks * 256);
146 
147 	skb = dev_alloc_skb(rcv_pkt_len);
148 	if (!skb)
149 		return -ENOMEM;
150 
151 	status = rsi_sdio_host_intf_read_pkt(adapter, skb->data, rcv_pkt_len);
152 	if (status) {
153 		rsi_dbg(ERR_ZONE, "%s: Failed to read packet from card\n",
154 			__func__);
155 		dev_kfree_skb(skb);
156 		return status;
157 	}
158 	skb_put(skb, rcv_pkt_len);
159 	skb_queue_tail(&dev->rx_q.head, skb);
160 	dev->rx_q.num_rx_pkts++;
161 
162 	rsi_set_event(&dev->rx_thread.event);
163 
164 	return 0;
165 }
166 
167 /**
168  * rsi_init_sdio_slave_regs() - This function does the actual initialization
169  *				of SDBUS slave registers.
170  * @adapter: Pointer to the adapter structure.
171  *
172  * Return: status: 0 on success, -1 on failure.
173  */
174 int rsi_init_sdio_slave_regs(struct rsi_hw *adapter)
175 {
176 	struct rsi_91x_sdiodev *dev =
177 		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
178 	u8 function = 0;
179 	u8 byte;
180 	int status = 0;
181 
182 	if (dev->next_read_delay) {
183 		byte = dev->next_read_delay;
184 		status = rsi_sdio_write_register(adapter,
185 						 function,
186 						 SDIO_NXT_RD_DELAY2,
187 						 &byte);
188 		if (status) {
189 			rsi_dbg(ERR_ZONE,
190 				"%s: Failed to write SDIO_NXT_RD_DELAY2\n",
191 				__func__);
192 			return -1;
193 		}
194 	}
195 
196 	if (dev->sdio_high_speed_enable) {
197 		rsi_dbg(INIT_ZONE, "%s: Enabling SDIO High speed\n", __func__);
198 		byte = 0x3;
199 
200 		status = rsi_sdio_write_register(adapter,
201 						 function,
202 						 SDIO_REG_HIGH_SPEED,
203 						 &byte);
204 		if (status) {
205 			rsi_dbg(ERR_ZONE,
206 				"%s: Failed to enable SDIO high speed\n",
207 				__func__);
208 			return -1;
209 		}
210 	}
211 
212 	/* This tells SDIO FIFO when to start read to host */
213 	rsi_dbg(INIT_ZONE, "%s: Initializing SDIO read start level\n", __func__);
214 	byte = 0x24;
215 
216 	status = rsi_sdio_write_register(adapter,
217 					 function,
218 					 SDIO_READ_START_LVL,
219 					 &byte);
220 	if (status) {
221 		rsi_dbg(ERR_ZONE,
222 			"%s: Failed to write SDIO_READ_START_LVL\n", __func__);
223 		return -1;
224 	}
225 
226 	rsi_dbg(INIT_ZONE, "%s: Initializing FIFO ctrl registers\n", __func__);
227 	byte = (128 - 32);
228 
229 	status = rsi_sdio_write_register(adapter,
230 					 function,
231 					 SDIO_READ_FIFO_CTL,
232 					 &byte);
233 	if (status) {
234 		rsi_dbg(ERR_ZONE,
235 			"%s: Failed to write SDIO_READ_FIFO_CTL\n", __func__);
236 		return -1;
237 	}
238 
239 	byte = 32;
240 	status = rsi_sdio_write_register(adapter,
241 					 function,
242 					 SDIO_WRITE_FIFO_CTL,
243 					 &byte);
244 	if (status) {
245 		rsi_dbg(ERR_ZONE,
246 			"%s: Failed to write SDIO_WRITE_FIFO_CTL\n", __func__);
247 		return -1;
248 	}
249 
250 	return 0;
251 }
252 
253 /**
254  * rsi_interrupt_handler() - This function read and process SDIO interrupts.
255  * @adapter: Pointer to the adapter structure.
256  *
257  * Return: None.
258  */
259 void rsi_interrupt_handler(struct rsi_hw *adapter)
260 {
261 	struct rsi_common *common = adapter->priv;
262 	struct rsi_91x_sdiodev *dev =
263 		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
264 	int status;
265 	enum sdio_interrupt_type isr_type;
266 	u8 isr_status = 0;
267 	u8 fw_status = 0;
268 
269 	dev->rx_info.sdio_int_counter++;
270 
271 	do {
272 		mutex_lock(&common->rx_lock);
273 		status = rsi_sdio_read_register(common->priv,
274 						RSI_FN1_INT_REGISTER,
275 						&isr_status);
276 		if (status) {
277 			rsi_dbg(ERR_ZONE,
278 				"%s: Failed to Read Intr Status Register\n",
279 				__func__);
280 			mutex_unlock(&common->rx_lock);
281 			return;
282 		}
283 		adapter->interrupt_status = isr_status;
284 
285 		if (isr_status == 0) {
286 			rsi_set_event(&common->tx_thread.event);
287 			dev->rx_info.sdio_intr_status_zero++;
288 			mutex_unlock(&common->rx_lock);
289 			return;
290 		}
291 
292 		rsi_dbg(ISR_ZONE, "%s: Intr_status = %x %d %d\n",
293 			__func__, isr_status, (1 << MSDU_PKT_PENDING),
294 			(1 << FW_ASSERT_IND));
295 
296 		do {
297 			RSI_GET_SDIO_INTERRUPT_TYPE(isr_status, isr_type);
298 
299 			switch (isr_type) {
300 			case BUFFER_AVAILABLE:
301 				status = rsi_sdio_check_buffer_status(adapter,
302 								      0);
303 				if (status < 0)
304 					rsi_dbg(ERR_ZONE,
305 						"%s: Failed to check buffer status\n",
306 						__func__);
307 				rsi_sdio_ack_intr(common->priv,
308 						  (1 << PKT_BUFF_AVAILABLE));
309 				rsi_set_event(&common->tx_thread.event);
310 
311 				rsi_dbg(ISR_ZONE,
312 					"%s: ==> BUFFER_AVAILABLE <==\n",
313 					__func__);
314 				dev->buff_status_updated = true;
315 				break;
316 
317 			case FIRMWARE_ASSERT_IND:
318 				rsi_dbg(ERR_ZONE,
319 					"%s: ==> FIRMWARE Assert <==\n",
320 					__func__);
321 				status = rsi_sdio_read_register(common->priv,
322 							SDIO_FW_STATUS_REG,
323 							&fw_status);
324 				if (status) {
325 					rsi_dbg(ERR_ZONE,
326 						"%s: Failed to read f/w reg\n",
327 						__func__);
328 				} else {
329 					rsi_dbg(ERR_ZONE,
330 						"%s: Firmware Status is 0x%x\n",
331 						__func__ , fw_status);
332 					rsi_sdio_ack_intr(common->priv,
333 							  (1 << FW_ASSERT_IND));
334 				}
335 
336 				common->fsm_state = FSM_CARD_NOT_READY;
337 				break;
338 
339 			case MSDU_PACKET_PENDING:
340 				rsi_dbg(ISR_ZONE, "Pkt pending interrupt\n");
341 				dev->rx_info.total_sdio_msdu_pending_intr++;
342 
343 				status = rsi_process_pkt(common);
344 				if (status) {
345 					rsi_dbg(ERR_ZONE,
346 						"%s: Failed to read pkt\n",
347 						__func__);
348 					mutex_unlock(&common->rx_lock);
349 					return;
350 				}
351 				break;
352 			default:
353 				rsi_sdio_ack_intr(common->priv, isr_status);
354 				dev->rx_info.total_sdio_unknown_intr++;
355 				isr_status = 0;
356 				rsi_dbg(ISR_ZONE,
357 					"Unknown Interrupt %x\n",
358 					isr_status);
359 				break;
360 			}
361 			isr_status ^= BIT(isr_type - 1);
362 		} while (isr_status);
363 		mutex_unlock(&common->rx_lock);
364 	} while (1);
365 }
366 
367 /* This function is used to read buffer status register and
368  * set relevant fields in rsi_91x_sdiodev struct.
369  */
370 int rsi_sdio_check_buffer_status(struct rsi_hw *adapter, u8 q_num)
371 {
372 	struct rsi_common *common = adapter->priv;
373 	struct rsi_91x_sdiodev *dev =
374 		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
375 	u8 buf_status = 0;
376 	int status = 0;
377 	static int counter = 4;
378 
379 	if (!dev->buff_status_updated && counter) {
380 		counter--;
381 		goto out;
382 	}
383 
384 	dev->buff_status_updated = false;
385 	status = rsi_sdio_read_register(common->priv,
386 					RSI_DEVICE_BUFFER_STATUS_REGISTER,
387 					&buf_status);
388 
389 	if (status) {
390 		rsi_dbg(ERR_ZONE,
391 			"%s: Failed to read status register\n", __func__);
392 		return -1;
393 	}
394 
395 	if (buf_status & (BIT(PKT_MGMT_BUFF_FULL))) {
396 		if (!dev->rx_info.mgmt_buffer_full)
397 			dev->rx_info.mgmt_buf_full_counter++;
398 		dev->rx_info.mgmt_buffer_full = true;
399 	} else {
400 		dev->rx_info.mgmt_buffer_full = false;
401 	}
402 
403 	if (buf_status & (BIT(PKT_BUFF_FULL))) {
404 		if (!dev->rx_info.buffer_full)
405 			dev->rx_info.buf_full_counter++;
406 		dev->rx_info.buffer_full = true;
407 	} else {
408 		dev->rx_info.buffer_full = false;
409 	}
410 
411 	if (buf_status & (BIT(PKT_BUFF_SEMI_FULL))) {
412 		if (!dev->rx_info.semi_buffer_full)
413 			dev->rx_info.buf_semi_full_counter++;
414 		dev->rx_info.semi_buffer_full = true;
415 	} else {
416 		dev->rx_info.semi_buffer_full = false;
417 	}
418 
419 	if (dev->rx_info.mgmt_buffer_full || dev->rx_info.buf_full_counter)
420 		counter = 1;
421 	else
422 		counter = 4;
423 
424 out:
425 	if ((q_num == MGMT_SOFT_Q) && (dev->rx_info.mgmt_buffer_full))
426 		return QUEUE_FULL;
427 
428 	if ((q_num < MGMT_SOFT_Q) && (dev->rx_info.buffer_full))
429 		return QUEUE_FULL;
430 
431 	return QUEUE_NOT_FULL;
432 }
433 
434 /**
435  * rsi_sdio_determine_event_timeout() - This Function determines the event
436  *					timeout duration.
437  * @adapter: Pointer to the adapter structure.
438  *
439  * Return: timeout duration is returned.
440  */
441 int rsi_sdio_determine_event_timeout(struct rsi_hw *adapter)
442 {
443 	struct rsi_91x_sdiodev *dev =
444 		(struct rsi_91x_sdiodev *)adapter->rsi_dev;
445 
446 	/* Once buffer full is seen, event timeout to occur every 2 msecs */
447 	if (dev->rx_info.buffer_full)
448 		return 2;
449 
450 	return EVENT_WAIT_FOREVER;
451 }
452