xref: /linux/drivers/spi/spi-geni-qcom.c (revision 9f582e39712f950f13dfa1ad49748a90937e48be)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3 
4 #include <linux/clk.h>
5 #include <linux/dmaengine.h>
6 #include <linux/dma-mapping.h>
7 #include <linux/dma/qcom-gpi-dma.h>
8 #include <linux/interrupt.h>
9 #include <linux/io.h>
10 #include <linux/log2.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_opp.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/property.h>
16 #include <linux/soc/qcom/geni-se.h>
17 #include <linux/spi/spi.h>
18 #include <linux/spinlock.h>
19 
20 /* SPI SE specific registers and respective register fields */
21 #define SE_SPI_CPHA		0x224
22 #define CPHA			BIT(0)
23 
24 #define SE_SPI_LOOPBACK		0x22c
25 #define LOOPBACK_ENABLE		0x1
26 #define NORMAL_MODE		0x0
27 #define LOOPBACK_MSK		GENMASK(1, 0)
28 
29 #define SE_SPI_CPOL		0x230
30 #define CPOL			BIT(2)
31 
32 #define SE_SPI_DEMUX_OUTPUT_INV	0x24c
33 #define CS_DEMUX_OUTPUT_INV_MSK	GENMASK(3, 0)
34 
35 #define SE_SPI_DEMUX_SEL	0x250
36 #define CS_DEMUX_OUTPUT_SEL	GENMASK(3, 0)
37 
38 #define SE_SPI_TRANS_CFG	0x25c
39 #define CS_TOGGLE		BIT(1)
40 
41 #define SE_SPI_WORD_LEN		0x268
42 #define WORD_LEN_MSK		GENMASK(9, 0)
43 #define MIN_WORD_LEN		4
44 
45 #define SE_SPI_TX_TRANS_LEN	0x26c
46 #define SE_SPI_RX_TRANS_LEN	0x270
47 #define TRANS_LEN_MSK		GENMASK(23, 0)
48 
49 #define SE_SPI_PRE_POST_CMD_DLY	0x274
50 
51 #define SE_SPI_DELAY_COUNTERS	0x278
52 #define SPI_INTER_WORDS_DELAY_MSK	GENMASK(9, 0)
53 #define SPI_CS_CLK_DELAY_MSK		GENMASK(19, 10)
54 #define SPI_CS_CLK_DELAY_SHFT		10
55 
56 #define SE_SPI_SLAVE_EN				(0x2BC)
57 #define SPI_SLAVE_EN				BIT(0)
58 
59 /* M_CMD OP codes for SPI */
60 #define SPI_TX_ONLY		1
61 #define SPI_RX_ONLY		2
62 #define SPI_TX_RX		7
63 #define SPI_CS_ASSERT		8
64 #define SPI_CS_DEASSERT		9
65 #define SPI_SCK_ONLY		10
66 /* M_CMD params for SPI */
67 #define SPI_PRE_CMD_DELAY	BIT(0)
68 #define TIMESTAMP_BEFORE	BIT(1)
69 #define FRAGMENTATION		BIT(2)
70 #define TIMESTAMP_AFTER		BIT(3)
71 #define POST_CMD_DELAY		BIT(4)
72 
73 #define GSI_LOOPBACK_EN		BIT(0)
74 #define GSI_CS_TOGGLE		BIT(3)
75 #define GSI_CPHA		BIT(4)
76 #define GSI_CPOL		BIT(5)
77 
78 struct spi_geni_master {
79 	struct geni_se se;
80 	struct device *dev;
81 	u32 tx_fifo_depth;
82 	u32 fifo_width_bits;
83 	u32 tx_wm;
84 	u32 last_mode;
85 	u8 last_cs;
86 	unsigned long cur_speed_hz;
87 	unsigned long cur_sclk_hz;
88 	unsigned int cur_bits_per_word;
89 	unsigned int tx_rem_bytes;
90 	unsigned int rx_rem_bytes;
91 	const struct spi_transfer *cur_xfer;
92 	struct completion cs_done;
93 	struct completion cancel_done;
94 	struct completion abort_done;
95 	struct completion tx_reset_done;
96 	struct completion rx_reset_done;
97 	unsigned int oversampling;
98 	spinlock_t lock;
99 	int irq;
100 	bool cs_flag;
101 	bool abort_failed;
102 	struct dma_chan *tx;
103 	struct dma_chan *rx;
104 	int cur_xfer_mode;
105 };
106 
spi_slv_setup(struct spi_geni_master * mas)107 static void spi_slv_setup(struct spi_geni_master *mas)
108 {
109 	struct geni_se *se = &mas->se;
110 
111 	writel(SPI_SLAVE_EN, se->base + SE_SPI_SLAVE_EN);
112 	writel(GENI_IO_MUX_0_EN, se->base + GENI_OUTPUT_CTRL);
113 	writel(START_TRIGGER, se->base + SE_GENI_CFG_SEQ_START);
114 	dev_dbg(mas->dev, "spi slave setup done\n");
115 }
116 
get_spi_clk_cfg(unsigned int speed_hz,struct spi_geni_master * mas,unsigned int * clk_idx,unsigned int * clk_div)117 static int get_spi_clk_cfg(unsigned int speed_hz,
118 			struct spi_geni_master *mas,
119 			unsigned int *clk_idx,
120 			unsigned int *clk_div)
121 {
122 	unsigned long sclk_freq;
123 	unsigned int actual_hz;
124 	int ret;
125 
126 	ret = geni_se_clk_freq_match(&mas->se,
127 				speed_hz * mas->oversampling,
128 				clk_idx, &sclk_freq, false);
129 	if (ret) {
130 		dev_err(mas->dev, "Failed(%d) to find src clk for %dHz\n",
131 							ret, speed_hz);
132 		return ret;
133 	}
134 
135 	*clk_div = DIV_ROUND_UP(sclk_freq, mas->oversampling * speed_hz);
136 	actual_hz = sclk_freq / (mas->oversampling * *clk_div);
137 
138 	dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz,
139 				actual_hz, sclk_freq, *clk_idx, *clk_div);
140 	ret = dev_pm_opp_set_rate(mas->dev, sclk_freq);
141 	if (ret)
142 		dev_err(mas->dev, "dev_pm_opp_set_rate failed %d\n", ret);
143 	else
144 		mas->cur_sclk_hz = sclk_freq;
145 
146 	return ret;
147 }
148 
handle_se_timeout(struct spi_controller * spi)149 static void handle_se_timeout(struct spi_controller *spi)
150 {
151 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
152 	unsigned long time_left;
153 	struct geni_se *se = &mas->se;
154 	const struct spi_transfer *xfer;
155 
156 	spin_lock_irq(&mas->lock);
157 	if (mas->cur_xfer_mode == GENI_SE_FIFO)
158 		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
159 
160 	xfer = mas->cur_xfer;
161 	mas->cur_xfer = NULL;
162 
163 	/* The controller doesn't support the Cancel commnand in target mode */
164 	if (!spi->target) {
165 		reinit_completion(&mas->cancel_done);
166 		geni_se_cancel_m_cmd(se);
167 
168 		spin_unlock_irq(&mas->lock);
169 
170 		time_left = wait_for_completion_timeout(&mas->cancel_done, HZ);
171 		if (time_left)
172 			goto reset_if_dma;
173 
174 		spin_lock_irq(&mas->lock);
175 	}
176 
177 	reinit_completion(&mas->abort_done);
178 	geni_se_abort_m_cmd(se);
179 	spin_unlock_irq(&mas->lock);
180 
181 	time_left = wait_for_completion_timeout(&mas->abort_done, HZ);
182 	if (!time_left) {
183 		dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
184 
185 		/*
186 		 * No need for a lock since SPI core has a lock and we never
187 		 * access this from an interrupt.
188 		 */
189 		mas->abort_failed = true;
190 	}
191 
192 reset_if_dma:
193 	if (mas->cur_xfer_mode == GENI_SE_DMA) {
194 		if (xfer) {
195 			if (xfer->tx_buf) {
196 				spin_lock_irq(&mas->lock);
197 				reinit_completion(&mas->tx_reset_done);
198 				writel(1, se->base + SE_DMA_TX_FSM_RST);
199 				spin_unlock_irq(&mas->lock);
200 				time_left = wait_for_completion_timeout(&mas->tx_reset_done, HZ);
201 				if (!time_left)
202 					dev_err(mas->dev, "DMA TX RESET failed\n");
203 			}
204 			if (xfer->rx_buf) {
205 				spin_lock_irq(&mas->lock);
206 				reinit_completion(&mas->rx_reset_done);
207 				writel(1, se->base + SE_DMA_RX_FSM_RST);
208 				spin_unlock_irq(&mas->lock);
209 				time_left = wait_for_completion_timeout(&mas->rx_reset_done, HZ);
210 				if (!time_left)
211 					dev_err(mas->dev, "DMA RX RESET failed\n");
212 			}
213 		} else {
214 			/*
215 			 * This can happen if a timeout happened and we had to wait
216 			 * for lock in this function because isr was holding the lock
217 			 * and handling transfer completion at that time.
218 			 */
219 			dev_warn(mas->dev, "Cancel/Abort on completed SPI transfer\n");
220 		}
221 	}
222 }
223 
handle_gpi_timeout(struct spi_controller * spi)224 static void handle_gpi_timeout(struct spi_controller *spi)
225 {
226 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
227 
228 	dmaengine_terminate_sync(mas->tx);
229 	dmaengine_terminate_sync(mas->rx);
230 }
231 
spi_geni_handle_err(struct spi_controller * spi,struct spi_message * msg)232 static void spi_geni_handle_err(struct spi_controller *spi, struct spi_message *msg)
233 {
234 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
235 
236 	switch (mas->cur_xfer_mode) {
237 	case GENI_SE_FIFO:
238 	case GENI_SE_DMA:
239 		handle_se_timeout(spi);
240 		break;
241 	case GENI_GPI_DMA:
242 		handle_gpi_timeout(spi);
243 		break;
244 	default:
245 		dev_err(mas->dev, "Abort on Mode:%d not supported", mas->cur_xfer_mode);
246 	}
247 }
248 
spi_geni_is_abort_still_pending(struct spi_geni_master * mas)249 static bool spi_geni_is_abort_still_pending(struct spi_geni_master *mas)
250 {
251 	struct geni_se *se = &mas->se;
252 	u32 m_irq, m_irq_en;
253 
254 	if (!mas->abort_failed)
255 		return false;
256 
257 	/*
258 	 * The only known case where a transfer times out and then a cancel
259 	 * times out then an abort times out is if something is blocking our
260 	 * interrupt handler from running.  Avoid starting any new transfers
261 	 * until that sorts itself out.
262 	 */
263 	spin_lock_irq(&mas->lock);
264 	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
265 	m_irq_en = readl(se->base + SE_GENI_M_IRQ_EN);
266 	spin_unlock_irq(&mas->lock);
267 
268 	if (m_irq & m_irq_en) {
269 		dev_err(mas->dev, "Interrupts pending after abort: %#010x\n",
270 			m_irq & m_irq_en);
271 		return true;
272 	}
273 
274 	/*
275 	 * If we're here the problem resolved itself so no need to check more
276 	 * on future transfers.
277 	 */
278 	mas->abort_failed = false;
279 
280 	return false;
281 }
282 
spi_setup_word_len(struct spi_geni_master * mas,u16 mode,unsigned int bits_per_word)283 static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode,
284 					unsigned int bits_per_word)
285 {
286 	unsigned int pack_words;
287 	bool msb_first = (mode & SPI_LSB_FIRST) ? false : true;
288 	struct geni_se *se = &mas->se;
289 	u32 word_len;
290 
291 	/*
292 	 * If bits_per_word isn't a byte aligned value, set the packing to be
293 	 * 1 SPI word per FIFO word.
294 	 */
295 	if (!(mas->fifo_width_bits % bits_per_word))
296 		pack_words = mas->fifo_width_bits / bits_per_word;
297 	else
298 		pack_words = 1;
299 	geni_se_config_packing(&mas->se, bits_per_word, pack_words, msb_first,
300 								true, true);
301 	word_len = (bits_per_word - MIN_WORD_LEN) & WORD_LEN_MSK;
302 	writel(word_len, se->base + SE_SPI_WORD_LEN);
303 }
304 
geni_spi_set_clock_and_bw(struct spi_geni_master * mas,unsigned long clk_hz)305 static int geni_spi_set_clock_and_bw(struct spi_geni_master *mas,
306 					unsigned long clk_hz)
307 {
308 	u32 clk_sel, m_clk_cfg, idx, div;
309 	struct geni_se *se = &mas->se;
310 	int ret;
311 
312 	if (clk_hz == mas->cur_speed_hz)
313 		return 0;
314 
315 	ret = get_spi_clk_cfg(clk_hz, mas, &idx, &div);
316 	if (ret) {
317 		dev_err(mas->dev, "Err setting clk to %lu: %d\n", clk_hz, ret);
318 		return ret;
319 	}
320 
321 	/*
322 	 * SPI core clock gets configured with the requested frequency
323 	 * or the frequency closer to the requested frequency.
324 	 * For that reason requested frequency is stored in the
325 	 * cur_speed_hz and referred in the consecutive transfer instead
326 	 * of calling clk_get_rate() API.
327 	 */
328 	mas->cur_speed_hz = clk_hz;
329 
330 	clk_sel = idx & CLK_SEL_MSK;
331 	m_clk_cfg = (div << CLK_DIV_SHFT) | SER_CLK_EN;
332 	writel(clk_sel, se->base + SE_GENI_CLK_SEL);
333 	writel(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG);
334 
335 	/* Set BW quota for CPU as driver supports FIFO mode only. */
336 	se->icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(mas->cur_speed_hz);
337 	ret = geni_icc_set_bw(se);
338 	if (ret)
339 		return ret;
340 
341 	return 0;
342 }
343 
setup_fifo_params(struct spi_device * spi_slv,struct spi_controller * spi)344 static int setup_fifo_params(struct spi_device *spi_slv,
345 					struct spi_controller *spi)
346 {
347 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
348 	struct geni_se *se = &mas->se;
349 	u8 chipselect = spi_get_chipselect(spi_slv, 0);
350 	bool cs_changed = (mas->last_cs != chipselect);
351 	u32 mode_changed = mas->last_mode ^ spi_slv->mode;
352 
353 	mas->last_cs = chipselect;
354 	mas->last_mode = spi_slv->mode;
355 
356 	if (mode_changed & SPI_LSB_FIRST)
357 		mas->cur_bits_per_word = 0; /* force next setup_se_xfer to call spi_setup_word_len */
358 	if (mode_changed & SPI_LOOP)
359 		writel((spi_slv->mode & SPI_LOOP) ? LOOPBACK_ENABLE : 0, se->base + SE_SPI_LOOPBACK);
360 	if (cs_changed)
361 		writel(chipselect, se->base + SE_SPI_DEMUX_SEL);
362 	if (mode_changed & SPI_CPHA)
363 		writel((spi_slv->mode & SPI_CPHA) ? CPHA : 0, se->base + SE_SPI_CPHA);
364 	if (mode_changed & SPI_CPOL)
365 		writel((spi_slv->mode & SPI_CPOL) ? CPOL : 0, se->base + SE_SPI_CPOL);
366 	if ((mode_changed & SPI_CS_HIGH) || (cs_changed && (spi_slv->mode & SPI_CS_HIGH)))
367 		writel((spi_slv->mode & SPI_CS_HIGH) ? BIT(chipselect) : 0, se->base + SE_SPI_DEMUX_OUTPUT_INV);
368 
369 	return 0;
370 }
371 
372 static void
spi_gsi_callback_result(void * cb,const struct dmaengine_result * result)373 spi_gsi_callback_result(void *cb, const struct dmaengine_result *result)
374 {
375 	struct spi_controller *spi = cb;
376 
377 	spi->cur_msg->status = -EIO;
378 	if (result->result != DMA_TRANS_NOERROR) {
379 		dev_err(&spi->dev, "DMA txn failed: %d\n", result->result);
380 		spi_finalize_current_transfer(spi);
381 		return;
382 	}
383 
384 	if (!result->residue) {
385 		spi->cur_msg->status = 0;
386 		dev_dbg(&spi->dev, "DMA txn completed\n");
387 	} else {
388 		dev_err(&spi->dev, "DMA xfer has pending: %d\n", result->residue);
389 	}
390 
391 	spi_finalize_current_transfer(spi);
392 }
393 
setup_gsi_xfer(struct spi_transfer * xfer,struct spi_geni_master * mas,struct spi_device * spi_slv,struct spi_controller * spi)394 static int setup_gsi_xfer(struct spi_transfer *xfer, struct spi_geni_master *mas,
395 			  struct spi_device *spi_slv, struct spi_controller *spi)
396 {
397 	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
398 	struct dma_slave_config config = {};
399 	struct gpi_spi_config peripheral = {};
400 	struct dma_async_tx_descriptor *tx_desc, *rx_desc;
401 	int ret;
402 
403 	config.peripheral_config = &peripheral;
404 	config.peripheral_size = sizeof(peripheral);
405 	peripheral.set_config = true;
406 
407 	if (xfer->bits_per_word != mas->cur_bits_per_word ||
408 	    xfer->speed_hz != mas->cur_speed_hz) {
409 		mas->cur_bits_per_word = xfer->bits_per_word;
410 		mas->cur_speed_hz = xfer->speed_hz;
411 	}
412 
413 	if (xfer->tx_buf && xfer->rx_buf) {
414 		peripheral.cmd = SPI_DUPLEX;
415 	} else if (xfer->tx_buf) {
416 		peripheral.cmd = SPI_TX;
417 		peripheral.rx_len = 0;
418 	} else if (xfer->rx_buf) {
419 		peripheral.cmd = SPI_RX;
420 		if (!(mas->cur_bits_per_word % MIN_WORD_LEN)) {
421 			peripheral.rx_len = ((xfer->len << 3) / mas->cur_bits_per_word);
422 		} else {
423 			int bytes_per_word = (mas->cur_bits_per_word / BITS_PER_BYTE) + 1;
424 
425 			peripheral.rx_len = (xfer->len / bytes_per_word);
426 		}
427 	}
428 
429 	peripheral.loopback_en = !!(spi_slv->mode & SPI_LOOP);
430 	peripheral.clock_pol_high = !!(spi_slv->mode & SPI_CPOL);
431 	peripheral.data_pol_high = !!(spi_slv->mode & SPI_CPHA);
432 	peripheral.cs = spi_get_chipselect(spi_slv, 0);
433 	peripheral.pack_en = true;
434 	peripheral.word_len = xfer->bits_per_word - MIN_WORD_LEN;
435 
436 	ret = get_spi_clk_cfg(mas->cur_speed_hz, mas,
437 			      &peripheral.clk_src, &peripheral.clk_div);
438 	if (ret) {
439 		dev_err(mas->dev, "Err in get_spi_clk_cfg() :%d\n", ret);
440 		return ret;
441 	}
442 
443 	if (!xfer->cs_change) {
444 		if (!list_is_last(&xfer->transfer_list, &spi->cur_msg->transfers))
445 			peripheral.fragmentation = FRAGMENTATION;
446 	}
447 
448 	if (peripheral.cmd & SPI_RX) {
449 		dmaengine_slave_config(mas->rx, &config);
450 		rx_desc = dmaengine_prep_slave_sg(mas->rx, xfer->rx_sg.sgl, xfer->rx_sg.nents,
451 						  DMA_DEV_TO_MEM, flags);
452 		if (!rx_desc) {
453 			dev_err(mas->dev, "Err setting up rx desc\n");
454 			return -EIO;
455 		}
456 	}
457 
458 	/*
459 	 * Prepare the TX always, even for RX or tx_buf being null, we would
460 	 * need TX to be prepared per GSI spec
461 	 */
462 	dmaengine_slave_config(mas->tx, &config);
463 	tx_desc = dmaengine_prep_slave_sg(mas->tx, xfer->tx_sg.sgl, xfer->tx_sg.nents,
464 					  DMA_MEM_TO_DEV, flags);
465 	if (!tx_desc) {
466 		dev_err(mas->dev, "Err setting up tx desc\n");
467 		return -EIO;
468 	}
469 
470 	tx_desc->callback_result = spi_gsi_callback_result;
471 	tx_desc->callback_param = spi;
472 
473 	if (peripheral.cmd & SPI_RX)
474 		dmaengine_submit(rx_desc);
475 	dmaengine_submit(tx_desc);
476 
477 	if (peripheral.cmd & SPI_RX)
478 		dma_async_issue_pending(mas->rx);
479 
480 	dma_async_issue_pending(mas->tx);
481 	return 1;
482 }
483 
get_xfer_len_in_words(struct spi_transfer * xfer,struct spi_geni_master * mas)484 static u32 get_xfer_len_in_words(struct spi_transfer *xfer,
485 				struct spi_geni_master *mas)
486 {
487 	u32 len;
488 
489 	if (!(xfer->bits_per_word % MIN_WORD_LEN))
490 		len = xfer->len * BITS_PER_BYTE / xfer->bits_per_word;
491 	else
492 		len = xfer->len / (xfer->bits_per_word / BITS_PER_BYTE + 1);
493 	len &= TRANS_LEN_MSK;
494 
495 	return len;
496 }
497 
geni_can_dma(struct spi_controller * ctlr,struct spi_device * slv,struct spi_transfer * xfer)498 static bool geni_can_dma(struct spi_controller *ctlr,
499 			 struct spi_device *slv, struct spi_transfer *xfer)
500 {
501 	struct spi_geni_master *mas = spi_controller_get_devdata(slv->controller);
502 	u32 len, fifo_size;
503 
504 	if (mas->cur_xfer_mode == GENI_GPI_DMA)
505 		return true;
506 
507 	/* Set SE DMA mode for SPI target. */
508 	if (ctlr->target)
509 		return true;
510 
511 	len = get_xfer_len_in_words(xfer, mas);
512 	fifo_size = mas->tx_fifo_depth * mas->fifo_width_bits / xfer->bits_per_word;
513 
514 	if (len > fifo_size)
515 		return true;
516 	else
517 		return false;
518 }
519 
spi_geni_prepare_message(struct spi_controller * spi,struct spi_message * spi_msg)520 static int spi_geni_prepare_message(struct spi_controller *spi,
521 				    struct spi_message *spi_msg)
522 {
523 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
524 	int ret;
525 
526 	switch (mas->cur_xfer_mode) {
527 	case GENI_SE_FIFO:
528 	case GENI_SE_DMA:
529 		if (spi_geni_is_abort_still_pending(mas))
530 			return -EBUSY;
531 		ret = setup_fifo_params(spi_msg->spi, spi);
532 		if (ret)
533 			dev_err(mas->dev, "Couldn't select mode %d\n", ret);
534 		return ret;
535 
536 	case GENI_GPI_DMA:
537 		/* nothing to do for GPI DMA */
538 		return 0;
539 	}
540 
541 	dev_err(mas->dev, "Mode not supported %d", mas->cur_xfer_mode);
542 	return -EINVAL;
543 }
544 
spi_geni_release_dma_chan(void * data)545 static void spi_geni_release_dma_chan(void *data)
546 {
547 	struct spi_geni_master *mas = data;
548 
549 	if (mas->rx) {
550 		dma_release_channel(mas->rx);
551 		mas->rx = NULL;
552 	}
553 
554 	if (mas->tx) {
555 		dma_release_channel(mas->tx);
556 		mas->tx = NULL;
557 	}
558 }
559 
spi_geni_grab_gpi_chan(struct spi_geni_master * mas)560 static int spi_geni_grab_gpi_chan(struct spi_geni_master *mas)
561 {
562 	int ret;
563 
564 	mas->tx = dma_request_chan(mas->dev, "tx");
565 	if (IS_ERR(mas->tx)) {
566 		ret = dev_err_probe(mas->dev, PTR_ERR(mas->tx),
567 				    "Failed to get tx DMA ch\n");
568 		goto err_tx;
569 	}
570 
571 	mas->rx = dma_request_chan(mas->dev, "rx");
572 	if (IS_ERR(mas->rx)) {
573 		ret = dev_err_probe(mas->dev, PTR_ERR(mas->rx),
574 				    "Failed to get rx DMA ch\n");
575 		goto err_rx;
576 	}
577 
578 	ret = devm_add_action_or_reset(mas->dev, spi_geni_release_dma_chan, mas);
579 	if (ret) {
580 		dev_err(mas->dev, "Unable to add action.\n");
581 		return ret;
582 	}
583 
584 	return 0;
585 
586 err_rx:
587 	mas->rx = NULL;
588 	dma_release_channel(mas->tx);
589 err_tx:
590 	mas->tx = NULL;
591 	return ret;
592 }
593 
spi_geni_init(struct spi_geni_master * mas)594 static int spi_geni_init(struct spi_geni_master *mas)
595 {
596 	struct spi_controller *spi = dev_get_drvdata(mas->dev);
597 	struct geni_se *se = &mas->se;
598 	unsigned int proto, major, minor, ver;
599 	u32 spi_tx_cfg, fifo_disable;
600 	int ret = -ENXIO;
601 
602 	pm_runtime_get_sync(mas->dev);
603 
604 	proto = geni_se_read_proto(se);
605 
606 	if (spi->target) {
607 		if (proto != GENI_SE_SPI_SLAVE) {
608 			dev_err(mas->dev, "Invalid proto %d\n", proto);
609 			goto out_pm;
610 		}
611 		spi_slv_setup(mas);
612 	} else if (proto == GENI_SE_INVALID_PROTO) {
613 		ret = geni_load_se_firmware(se, GENI_SE_SPI);
614 		if (ret) {
615 			dev_err(mas->dev, "spi master firmware load failed ret: %d\n", ret);
616 			goto out_pm;
617 		}
618 	} else if (proto != GENI_SE_SPI) {
619 		dev_err(mas->dev, "Invalid proto %d\n", proto);
620 		goto out_pm;
621 	}
622 	mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se);
623 
624 	/* Width of Tx and Rx FIFO is same */
625 	mas->fifo_width_bits = geni_se_get_tx_fifo_width(se);
626 
627 	/*
628 	 * Hardware programming guide suggests to configure
629 	 * RX FIFO RFR level to fifo_depth-2.
630 	 */
631 	geni_se_init(se, mas->tx_fifo_depth - 3, mas->tx_fifo_depth - 2);
632 	/* Transmit an entire FIFO worth of data per IRQ */
633 	mas->tx_wm = 1;
634 	ver = geni_se_get_qup_hw_version(se);
635 	major = GENI_SE_VERSION_MAJOR(ver);
636 	minor = GENI_SE_VERSION_MINOR(ver);
637 
638 	if (major == 1 && minor == 0)
639 		mas->oversampling = 2;
640 	else
641 		mas->oversampling = 1;
642 
643 	fifo_disable = readl(se->base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE;
644 	switch (fifo_disable) {
645 	case 1:
646 		ret = spi_geni_grab_gpi_chan(mas);
647 		if (!ret) { /* success case */
648 			mas->cur_xfer_mode = GENI_GPI_DMA;
649 			geni_se_select_mode(se, GENI_GPI_DMA);
650 			dev_dbg(mas->dev, "Using GPI DMA mode for SPI\n");
651 			break;
652 		} else if (ret == -EPROBE_DEFER) {
653 			goto out_pm;
654 		}
655 		/*
656 		 * in case of failure to get gpi dma channel, we can still do the
657 		 * FIFO mode, so fallthrough
658 		 */
659 		dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n");
660 		fallthrough;
661 
662 	case 0:
663 		mas->cur_xfer_mode = GENI_SE_FIFO;
664 		geni_se_select_mode(se, GENI_SE_FIFO);
665 		/* setup_fifo_params assumes that these registers start with a zero value */
666 		writel(0, se->base + SE_SPI_LOOPBACK);
667 		writel(0, se->base + SE_SPI_DEMUX_SEL);
668 		writel(0, se->base + SE_SPI_CPHA);
669 		writel(0, se->base + SE_SPI_CPOL);
670 		writel(0, se->base + SE_SPI_DEMUX_OUTPUT_INV);
671 		ret = 0;
672 		break;
673 	}
674 
675 	/* We never control CS manually */
676 	if (!spi->target) {
677 		spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG);
678 		spi_tx_cfg &= ~CS_TOGGLE;
679 		writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG);
680 	}
681 
682 out_pm:
683 	pm_runtime_put(mas->dev);
684 	return ret;
685 }
686 
geni_byte_per_fifo_word(struct spi_geni_master * mas)687 static unsigned int geni_byte_per_fifo_word(struct spi_geni_master *mas)
688 {
689 	/*
690 	 * Calculate how many bytes we'll put in each FIFO word.  If the
691 	 * transfer words don't pack cleanly into a FIFO word we'll just put
692 	 * one transfer word in each FIFO word.  If they do pack we'll pack 'em.
693 	 */
694 	if (mas->fifo_width_bits % mas->cur_bits_per_word)
695 		return roundup_pow_of_two(DIV_ROUND_UP(mas->cur_bits_per_word,
696 						       BITS_PER_BYTE));
697 
698 	return mas->fifo_width_bits / BITS_PER_BYTE;
699 }
700 
geni_spi_handle_tx(struct spi_geni_master * mas)701 static bool geni_spi_handle_tx(struct spi_geni_master *mas)
702 {
703 	struct geni_se *se = &mas->se;
704 	unsigned int max_bytes;
705 	const u8 *tx_buf;
706 	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
707 	unsigned int i = 0;
708 
709 	/* Stop the watermark IRQ if nothing to send */
710 	if (!mas->cur_xfer) {
711 		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
712 		return false;
713 	}
714 
715 	max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * bytes_per_fifo_word;
716 	if (mas->tx_rem_bytes < max_bytes)
717 		max_bytes = mas->tx_rem_bytes;
718 
719 	tx_buf = mas->cur_xfer->tx_buf + mas->cur_xfer->len - mas->tx_rem_bytes;
720 	while (i < max_bytes) {
721 		unsigned int j;
722 		unsigned int bytes_to_write;
723 		u32 fifo_word = 0;
724 		u8 *fifo_byte = (u8 *)&fifo_word;
725 
726 		bytes_to_write = min(bytes_per_fifo_word, max_bytes - i);
727 		for (j = 0; j < bytes_to_write; j++)
728 			fifo_byte[j] = tx_buf[i++];
729 		iowrite32_rep(se->base + SE_GENI_TX_FIFOn, &fifo_word, 1);
730 	}
731 	mas->tx_rem_bytes -= max_bytes;
732 	if (!mas->tx_rem_bytes) {
733 		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
734 		return false;
735 	}
736 	return true;
737 }
738 
geni_spi_handle_rx(struct spi_geni_master * mas)739 static void geni_spi_handle_rx(struct spi_geni_master *mas)
740 {
741 	struct geni_se *se = &mas->se;
742 	u32 rx_fifo_status;
743 	unsigned int rx_bytes;
744 	unsigned int rx_last_byte_valid;
745 	u8 *rx_buf;
746 	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
747 	unsigned int i = 0;
748 
749 	rx_fifo_status = readl(se->base + SE_GENI_RX_FIFO_STATUS);
750 	rx_bytes = (rx_fifo_status & RX_FIFO_WC_MSK) * bytes_per_fifo_word;
751 	if (rx_fifo_status & RX_LAST) {
752 		rx_last_byte_valid = rx_fifo_status & RX_LAST_BYTE_VALID_MSK;
753 		rx_last_byte_valid >>= RX_LAST_BYTE_VALID_SHFT;
754 		if (rx_last_byte_valid && rx_last_byte_valid < 4)
755 			rx_bytes -= bytes_per_fifo_word - rx_last_byte_valid;
756 	}
757 
758 	/* Clear out the FIFO and bail if nowhere to put it */
759 	if (!mas->cur_xfer) {
760 		for (i = 0; i < DIV_ROUND_UP(rx_bytes, bytes_per_fifo_word); i++)
761 			readl(se->base + SE_GENI_RX_FIFOn);
762 		return;
763 	}
764 
765 	if (mas->rx_rem_bytes < rx_bytes)
766 		rx_bytes = mas->rx_rem_bytes;
767 
768 	rx_buf = mas->cur_xfer->rx_buf + mas->cur_xfer->len - mas->rx_rem_bytes;
769 	while (i < rx_bytes) {
770 		u32 fifo_word = 0;
771 		u8 *fifo_byte = (u8 *)&fifo_word;
772 		unsigned int bytes_to_read;
773 		unsigned int j;
774 
775 		bytes_to_read = min(bytes_per_fifo_word, rx_bytes - i);
776 		ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1);
777 		for (j = 0; j < bytes_to_read; j++)
778 			rx_buf[i++] = fifo_byte[j];
779 	}
780 	mas->rx_rem_bytes -= rx_bytes;
781 }
782 
setup_se_xfer(struct spi_transfer * xfer,struct spi_geni_master * mas,u16 mode,struct spi_controller * spi)783 static int setup_se_xfer(struct spi_transfer *xfer,
784 				struct spi_geni_master *mas,
785 				u16 mode, struct spi_controller *spi)
786 {
787 	u32 m_cmd = 0;
788 	u32 m_params = 0;
789 	u32 len;
790 	struct geni_se *se = &mas->se;
791 	int ret;
792 
793 	/*
794 	 * Ensure that our interrupt handler isn't still running from some
795 	 * prior command before we start messing with the hardware behind
796 	 * its back.  We don't need to _keep_ the lock here since we're only
797 	 * worried about racing with out interrupt handler.  The SPI core
798 	 * already handles making sure that we're not trying to do two
799 	 * transfers at once or setting a chip select and doing a transfer
800 	 * concurrently.
801 	 *
802 	 * NOTE: we actually _can't_ hold the lock here because possibly we
803 	 * might call clk_set_rate() which needs to be able to sleep.
804 	 */
805 	spin_lock_irq(&mas->lock);
806 	spin_unlock_irq(&mas->lock);
807 
808 	if (xfer->bits_per_word != mas->cur_bits_per_word) {
809 		spi_setup_word_len(mas, mode, xfer->bits_per_word);
810 		mas->cur_bits_per_word = xfer->bits_per_word;
811 	}
812 
813 	/* Speed and bits per word can be overridden per transfer */
814 	ret = geni_spi_set_clock_and_bw(mas, xfer->speed_hz);
815 	if (ret)
816 		return ret;
817 
818 	mas->tx_rem_bytes = 0;
819 	mas->rx_rem_bytes = 0;
820 
821 	len = get_xfer_len_in_words(xfer, mas);
822 
823 	mas->cur_xfer = xfer;
824 	if (xfer->tx_buf) {
825 		m_cmd |= SPI_TX_ONLY;
826 		mas->tx_rem_bytes = xfer->len;
827 		writel(len, se->base + SE_SPI_TX_TRANS_LEN);
828 	}
829 
830 	if (xfer->rx_buf) {
831 		m_cmd |= SPI_RX_ONLY;
832 		writel(len, se->base + SE_SPI_RX_TRANS_LEN);
833 		mas->rx_rem_bytes = xfer->len;
834 	}
835 
836 	/*
837 	 * Select DMA mode if sgt are present; and with only 1 entry
838 	 * This is not a serious limitation because the xfer buffers are
839 	 * expected to fit into in 1 entry almost always, and if any
840 	 * doesn't for any reason we fall back to FIFO mode anyway
841 	 */
842 	if (!xfer->tx_sg.nents && !xfer->rx_sg.nents)
843 		mas->cur_xfer_mode = GENI_SE_FIFO;
844 	else if (xfer->tx_sg.nents > 1 || xfer->rx_sg.nents > 1) {
845 		dev_warn_once(mas->dev, "Doing FIFO, cannot handle tx_nents-%d, rx_nents-%d\n",
846 			xfer->tx_sg.nents, xfer->rx_sg.nents);
847 		mas->cur_xfer_mode = GENI_SE_FIFO;
848 	} else
849 		mas->cur_xfer_mode = GENI_SE_DMA;
850 	geni_se_select_mode(se, mas->cur_xfer_mode);
851 
852 	if (!xfer->cs_change) {
853 		if (!list_is_last(&xfer->transfer_list, &spi->cur_msg->transfers))
854 			m_params = FRAGMENTATION;
855 	}
856 
857 	/*
858 	 * Lock around right before we start the transfer since our
859 	 * interrupt could come in at any time now.
860 	 */
861 	spin_lock_irq(&mas->lock);
862 	geni_se_setup_m_cmd(se, m_cmd, m_params);
863 
864 	if (mas->cur_xfer_mode == GENI_SE_DMA) {
865 		if (m_cmd & SPI_RX_ONLY)
866 			geni_se_rx_init_dma(se, sg_dma_address(xfer->rx_sg.sgl),
867 				sg_dma_len(xfer->rx_sg.sgl));
868 		if (m_cmd & SPI_TX_ONLY)
869 			geni_se_tx_init_dma(se, sg_dma_address(xfer->tx_sg.sgl),
870 				sg_dma_len(xfer->tx_sg.sgl));
871 	} else if (m_cmd & SPI_TX_ONLY) {
872 		if (geni_spi_handle_tx(mas))
873 			writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);
874 	}
875 
876 	spin_unlock_irq(&mas->lock);
877 	return ret;
878 }
879 
spi_geni_transfer_one(struct spi_controller * spi,struct spi_device * slv,struct spi_transfer * xfer)880 static int spi_geni_transfer_one(struct spi_controller *spi,
881 				 struct spi_device *slv,
882 				 struct spi_transfer *xfer)
883 {
884 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
885 	int ret;
886 
887 	if (spi_geni_is_abort_still_pending(mas))
888 		return -EBUSY;
889 
890 	/* Terminate and return success for 0 byte length transfer */
891 	if (!xfer->len)
892 		return 0;
893 
894 	if (mas->cur_xfer_mode == GENI_SE_FIFO || mas->cur_xfer_mode == GENI_SE_DMA) {
895 		ret = setup_se_xfer(xfer, mas, slv->mode, spi);
896 		/* SPI framework expects +ve ret code to wait for transfer complete */
897 		if (!ret)
898 			ret = 1;
899 		return ret;
900 	}
901 	return setup_gsi_xfer(xfer, mas, slv, spi);
902 }
903 
geni_spi_isr(int irq,void * data)904 static irqreturn_t geni_spi_isr(int irq, void *data)
905 {
906 	struct spi_controller *spi = data;
907 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
908 	struct geni_se *se = &mas->se;
909 	u32 m_irq, dma_tx_status, dma_rx_status;
910 
911 	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
912 	dma_tx_status = readl_relaxed(se->base + SE_DMA_TX_IRQ_STAT);
913 	dma_rx_status = readl_relaxed(se->base + SE_DMA_RX_IRQ_STAT);
914 
915 	if (!m_irq && !dma_tx_status && !dma_rx_status)
916 		return IRQ_NONE;
917 
918 	if (m_irq & (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |
919 		     M_RX_FIFO_RD_ERR_EN | M_RX_FIFO_WR_ERR_EN |
920 		     M_TX_FIFO_RD_ERR_EN | M_TX_FIFO_WR_ERR_EN))
921 		dev_warn(mas->dev, "Unexpected IRQ err status %#010x\n", m_irq);
922 
923 	spin_lock(&mas->lock);
924 
925 	if (mas->cur_xfer_mode == GENI_SE_FIFO) {
926 		if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
927 			geni_spi_handle_rx(mas);
928 
929 		if (m_irq & M_TX_FIFO_WATERMARK_EN)
930 			geni_spi_handle_tx(mas);
931 
932 		if (m_irq & M_CMD_DONE_EN) {
933 			if (mas->cur_xfer) {
934 				spi_finalize_current_transfer(spi);
935 				mas->cur_xfer = NULL;
936 				/*
937 				 * If this happens, then a CMD_DONE came before all the
938 				 * Tx buffer bytes were sent out. This is unusual, log
939 				 * this condition and disable the WM interrupt to
940 				 * prevent the system from stalling due an interrupt
941 				 * storm.
942 				 *
943 				 * If this happens when all Rx bytes haven't been
944 				 * received, log the condition. The only known time
945 				 * this can happen is if bits_per_word != 8 and some
946 				 * registers that expect xfer lengths in num spi_words
947 				 * weren't written correctly.
948 				 */
949 				if (mas->tx_rem_bytes) {
950 					writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
951 					dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
952 						mas->tx_rem_bytes, mas->cur_bits_per_word);
953 				}
954 				if (mas->rx_rem_bytes)
955 					dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
956 						mas->rx_rem_bytes, mas->cur_bits_per_word);
957 			} else {
958 				complete(&mas->cs_done);
959 			}
960 		}
961 	} else if (mas->cur_xfer_mode == GENI_SE_DMA) {
962 		const struct spi_transfer *xfer = mas->cur_xfer;
963 
964 		if (dma_tx_status)
965 			writel(dma_tx_status, se->base + SE_DMA_TX_IRQ_CLR);
966 		if (dma_rx_status)
967 			writel(dma_rx_status, se->base + SE_DMA_RX_IRQ_CLR);
968 		if (dma_tx_status & TX_DMA_DONE)
969 			mas->tx_rem_bytes = 0;
970 		if (dma_rx_status & RX_DMA_DONE)
971 			mas->rx_rem_bytes = 0;
972 		if (dma_tx_status & TX_RESET_DONE)
973 			complete(&mas->tx_reset_done);
974 		if (dma_rx_status & RX_RESET_DONE)
975 			complete(&mas->rx_reset_done);
976 		if (!mas->tx_rem_bytes && !mas->rx_rem_bytes && xfer) {
977 			spi_finalize_current_transfer(spi);
978 			mas->cur_xfer = NULL;
979 		}
980 	}
981 
982 	if (m_irq & M_CMD_CANCEL_EN)
983 		complete(&mas->cancel_done);
984 	if (m_irq & M_CMD_ABORT_EN)
985 		complete(&mas->abort_done);
986 
987 	/*
988 	 * It's safe or a good idea to Ack all of our interrupts at the end
989 	 * of the function. Specifically:
990 	 * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and
991 	 *   clearing Acks. Clearing at the end relies on nobody else having
992 	 *   started a new transfer yet or else we could be clearing _their_
993 	 *   done bit, but everyone grabs the spinlock before starting a new
994 	 *   transfer.
995 	 * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear
996 	 *   to be "latched level" interrupts so it's important to clear them
997 	 *   _after_ you've handled the condition and always safe to do so
998 	 *   since they'll re-assert if they're still happening.
999 	 */
1000 	writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
1001 
1002 	spin_unlock(&mas->lock);
1003 
1004 	return IRQ_HANDLED;
1005 }
1006 
spi_geni_target_abort(struct spi_controller * spi)1007 static int spi_geni_target_abort(struct spi_controller *spi)
1008 {
1009 	if (!spi->cur_msg)
1010 		return 0;
1011 
1012 	handle_se_timeout(spi);
1013 	spi_finalize_current_transfer(spi);
1014 
1015 	return 0;
1016 }
1017 
spi_geni_probe(struct platform_device * pdev)1018 static int spi_geni_probe(struct platform_device *pdev)
1019 {
1020 	int ret, irq;
1021 	struct spi_controller *spi;
1022 	struct spi_geni_master *mas;
1023 	void __iomem *base;
1024 	struct clk *clk;
1025 	struct device *dev = &pdev->dev;
1026 
1027 	irq = platform_get_irq(pdev, 0);
1028 	if (irq < 0)
1029 		return irq;
1030 
1031 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
1032 	if (ret)
1033 		return dev_err_probe(dev, ret, "could not set DMA mask\n");
1034 
1035 	base = devm_platform_ioremap_resource(pdev, 0);
1036 	if (IS_ERR(base))
1037 		return PTR_ERR(base);
1038 
1039 	clk = devm_clk_get(dev, "se");
1040 	if (IS_ERR(clk))
1041 		return PTR_ERR(clk);
1042 
1043 	if (device_property_read_bool(dev, "spi-slave"))
1044 		spi = devm_spi_alloc_target(dev, sizeof(*mas));
1045 	else
1046 		spi = devm_spi_alloc_host(dev, sizeof(*mas));
1047 
1048 	if (!spi)
1049 		return -ENOMEM;
1050 
1051 	platform_set_drvdata(pdev, spi);
1052 	mas = spi_controller_get_devdata(spi);
1053 	mas->irq = irq;
1054 	mas->dev = dev;
1055 	mas->se.dev = dev;
1056 	mas->se.wrapper = dev_get_drvdata(dev->parent);
1057 	mas->se.base = base;
1058 	mas->se.clk = clk;
1059 
1060 	ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
1061 	if (ret)
1062 		return ret;
1063 	/* OPP table is optional */
1064 	ret = devm_pm_opp_of_add_table(&pdev->dev);
1065 	if (ret && ret != -ENODEV) {
1066 		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
1067 		return ret;
1068 	}
1069 
1070 	spi->bus_num = -1;
1071 	spi->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_CS_HIGH;
1072 	spi->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1073 	spi->num_chipselect = 4;
1074 	spi->max_speed_hz = 50000000;
1075 	spi->max_dma_len = 0xffff0; /* 24 bits for tx/rx dma length */
1076 	spi->prepare_message = spi_geni_prepare_message;
1077 	spi->transfer_one = spi_geni_transfer_one;
1078 	spi->can_dma = geni_can_dma;
1079 	spi->dma_map_dev = dev->parent;
1080 	spi->auto_runtime_pm = true;
1081 	spi->handle_err = spi_geni_handle_err;
1082 	spi->use_gpio_descriptors = true;
1083 
1084 	init_completion(&mas->cs_done);
1085 	init_completion(&mas->cancel_done);
1086 	init_completion(&mas->abort_done);
1087 	init_completion(&mas->tx_reset_done);
1088 	init_completion(&mas->rx_reset_done);
1089 	spin_lock_init(&mas->lock);
1090 
1091 	if (spi->target)
1092 		spi->target_abort = spi_geni_target_abort;
1093 
1094 	ret = geni_icc_get(&mas->se, NULL);
1095 	if (ret)
1096 		return ret;
1097 
1098 	pm_runtime_use_autosuspend(&pdev->dev);
1099 	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
1100 	ret = devm_pm_runtime_enable(dev);
1101 	if (ret)
1102 		return ret;
1103 
1104 	/* Set the bus quota to a reasonable value for register access */
1105 	mas->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(CORE_2X_50_MHZ);
1106 	mas->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
1107 
1108 	ret = geni_icc_set_bw(&mas->se);
1109 	if (ret)
1110 		return ret;
1111 
1112 	ret = spi_geni_init(mas);
1113 	if (ret)
1114 		return ret;
1115 
1116 	/*
1117 	 * TX is required per GSI spec, see setup_gsi_xfer().
1118 	 */
1119 	if (mas->cur_xfer_mode == GENI_GPI_DMA)
1120 		spi->flags = SPI_CONTROLLER_MUST_TX;
1121 
1122 	ret = devm_request_irq(dev, mas->irq, geni_spi_isr, 0, dev_name(dev), spi);
1123 	if (ret)
1124 		return ret;
1125 
1126 	return devm_spi_register_controller(dev, spi);
1127 }
1128 
spi_geni_runtime_suspend(struct device * dev)1129 static int __maybe_unused spi_geni_runtime_suspend(struct device *dev)
1130 {
1131 	struct spi_controller *spi = dev_get_drvdata(dev);
1132 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
1133 	int ret;
1134 
1135 	/* Drop the performance state vote */
1136 	dev_pm_opp_set_rate(dev, 0);
1137 
1138 	ret = geni_se_resources_off(&mas->se);
1139 	if (ret)
1140 		return ret;
1141 
1142 	return geni_icc_disable(&mas->se);
1143 }
1144 
spi_geni_runtime_resume(struct device * dev)1145 static int __maybe_unused spi_geni_runtime_resume(struct device *dev)
1146 {
1147 	struct spi_controller *spi = dev_get_drvdata(dev);
1148 	struct spi_geni_master *mas = spi_controller_get_devdata(spi);
1149 	int ret;
1150 
1151 	ret = geni_icc_enable(&mas->se);
1152 	if (ret)
1153 		return ret;
1154 
1155 	ret = geni_se_resources_on(&mas->se);
1156 	if (ret)
1157 		return ret;
1158 
1159 	return dev_pm_opp_set_rate(mas->dev, mas->cur_sclk_hz);
1160 }
1161 
spi_geni_suspend(struct device * dev)1162 static int __maybe_unused spi_geni_suspend(struct device *dev)
1163 {
1164 	struct spi_controller *spi = dev_get_drvdata(dev);
1165 	int ret;
1166 
1167 	ret = spi_controller_suspend(spi);
1168 	if (ret)
1169 		return ret;
1170 
1171 	ret = pm_runtime_force_suspend(dev);
1172 	if (ret)
1173 		spi_controller_resume(spi);
1174 
1175 	return ret;
1176 }
1177 
spi_geni_resume(struct device * dev)1178 static int __maybe_unused spi_geni_resume(struct device *dev)
1179 {
1180 	struct spi_controller *spi = dev_get_drvdata(dev);
1181 	int ret;
1182 
1183 	ret = pm_runtime_force_resume(dev);
1184 	if (ret)
1185 		return ret;
1186 
1187 	ret = spi_controller_resume(spi);
1188 	if (ret)
1189 		pm_runtime_force_suspend(dev);
1190 
1191 	return ret;
1192 }
1193 
1194 static const struct dev_pm_ops spi_geni_pm_ops = {
1195 	SET_RUNTIME_PM_OPS(spi_geni_runtime_suspend,
1196 					spi_geni_runtime_resume, NULL)
1197 	SET_SYSTEM_SLEEP_PM_OPS(spi_geni_suspend, spi_geni_resume)
1198 };
1199 
1200 static const struct of_device_id spi_geni_dt_match[] = {
1201 	{ .compatible = "qcom,geni-spi" },
1202 	{}
1203 };
1204 MODULE_DEVICE_TABLE(of, spi_geni_dt_match);
1205 
1206 static struct platform_driver spi_geni_driver = {
1207 	.probe  = spi_geni_probe,
1208 	.driver = {
1209 		.name = "geni_spi",
1210 		.pm = &spi_geni_pm_ops,
1211 		.of_match_table = spi_geni_dt_match,
1212 	},
1213 };
1214 module_platform_driver(spi_geni_driver);
1215 
1216 MODULE_DESCRIPTION("SPI driver for GENI based QUP cores");
1217 MODULE_LICENSE("GPL v2");
1218