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