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