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/interrupt.h>
6#include <linux/io.h>
7#include <linux/log2.h>
8#include <linux/module.h>
9#include <linux/platform_device.h>
10#include <linux/pm_opp.h>
11#include <linux/pm_runtime.h>
12#include <linux/qcom-geni-se.h>
13#include <linux/spi/spi.h>
14#include <linux/spinlock.h>
15
16/* SPI SE specific registers and respective register fields */
17#define SE_SPI_CPHA		0x224
18#define CPHA			BIT(0)
19
20#define SE_SPI_LOOPBACK		0x22c
21#define LOOPBACK_ENABLE		0x1
22#define NORMAL_MODE		0x0
23#define LOOPBACK_MSK		GENMASK(1, 0)
24
25#define SE_SPI_CPOL		0x230
26#define CPOL			BIT(2)
27
28#define SE_SPI_DEMUX_OUTPUT_INV	0x24c
29#define CS_DEMUX_OUTPUT_INV_MSK	GENMASK(3, 0)
30
31#define SE_SPI_DEMUX_SEL	0x250
32#define CS_DEMUX_OUTPUT_SEL	GENMASK(3, 0)
33
34#define SE_SPI_TRANS_CFG	0x25c
35#define CS_TOGGLE		BIT(1)
36
37#define SE_SPI_WORD_LEN		0x268
38#define WORD_LEN_MSK		GENMASK(9, 0)
39#define MIN_WORD_LEN		4
40
41#define SE_SPI_TX_TRANS_LEN	0x26c
42#define SE_SPI_RX_TRANS_LEN	0x270
43#define TRANS_LEN_MSK		GENMASK(23, 0)
44
45#define SE_SPI_PRE_POST_CMD_DLY	0x274
46
47#define SE_SPI_DELAY_COUNTERS	0x278
48#define SPI_INTER_WORDS_DELAY_MSK	GENMASK(9, 0)
49#define SPI_CS_CLK_DELAY_MSK		GENMASK(19, 10)
50#define SPI_CS_CLK_DELAY_SHFT		10
51
52/* M_CMD OP codes for SPI */
53#define SPI_TX_ONLY		1
54#define SPI_RX_ONLY		2
55#define SPI_TX_RX		7
56#define SPI_CS_ASSERT		8
57#define SPI_CS_DEASSERT		9
58#define SPI_SCK_ONLY		10
59/* M_CMD params for SPI */
60#define SPI_PRE_CMD_DELAY	BIT(0)
61#define TIMESTAMP_BEFORE	BIT(1)
62#define FRAGMENTATION		BIT(2)
63#define TIMESTAMP_AFTER		BIT(3)
64#define POST_CMD_DELAY		BIT(4)
65
66struct spi_geni_master {
67	struct geni_se se;
68	struct device *dev;
69	u32 tx_fifo_depth;
70	u32 fifo_width_bits;
71	u32 tx_wm;
72	u32 last_mode;
73	unsigned long cur_speed_hz;
74	unsigned long cur_sclk_hz;
75	unsigned int cur_bits_per_word;
76	unsigned int tx_rem_bytes;
77	unsigned int rx_rem_bytes;
78	const struct spi_transfer *cur_xfer;
79	struct completion cs_done;
80	struct completion cancel_done;
81	struct completion abort_done;
82	unsigned int oversampling;
83	spinlock_t lock;
84	int irq;
85	bool cs_flag;
86	bool abort_failed;
87};
88
89static int get_spi_clk_cfg(unsigned int speed_hz,
90			struct spi_geni_master *mas,
91			unsigned int *clk_idx,
92			unsigned int *clk_div)
93{
94	unsigned long sclk_freq;
95	unsigned int actual_hz;
96	int ret;
97
98	ret = geni_se_clk_freq_match(&mas->se,
99				speed_hz * mas->oversampling,
100				clk_idx, &sclk_freq, false);
101	if (ret) {
102		dev_err(mas->dev, "Failed(%d) to find src clk for %dHz\n",
103							ret, speed_hz);
104		return ret;
105	}
106
107	*clk_div = DIV_ROUND_UP(sclk_freq, mas->oversampling * speed_hz);
108	actual_hz = sclk_freq / (mas->oversampling * *clk_div);
109
110	dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz,
111				actual_hz, sclk_freq, *clk_idx, *clk_div);
112	ret = dev_pm_opp_set_rate(mas->dev, sclk_freq);
113	if (ret)
114		dev_err(mas->dev, "dev_pm_opp_set_rate failed %d\n", ret);
115	else
116		mas->cur_sclk_hz = sclk_freq;
117
118	return ret;
119}
120
121static void handle_fifo_timeout(struct spi_master *spi,
122				struct spi_message *msg)
123{
124	struct spi_geni_master *mas = spi_master_get_devdata(spi);
125	unsigned long time_left;
126	struct geni_se *se = &mas->se;
127
128	spin_lock_irq(&mas->lock);
129	reinit_completion(&mas->cancel_done);
130	writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
131	mas->cur_xfer = NULL;
132	geni_se_cancel_m_cmd(se);
133	spin_unlock_irq(&mas->lock);
134
135	time_left = wait_for_completion_timeout(&mas->cancel_done, HZ);
136	if (time_left)
137		return;
138
139	spin_lock_irq(&mas->lock);
140	reinit_completion(&mas->abort_done);
141	geni_se_abort_m_cmd(se);
142	spin_unlock_irq(&mas->lock);
143
144	time_left = wait_for_completion_timeout(&mas->abort_done, HZ);
145	if (!time_left) {
146		dev_err(mas->dev, "Failed to cancel/abort m_cmd\n");
147
148		/*
149		 * No need for a lock since SPI core has a lock and we never
150		 * access this from an interrupt.
151		 */
152		mas->abort_failed = true;
153	}
154}
155
156static bool spi_geni_is_abort_still_pending(struct spi_geni_master *mas)
157{
158	struct geni_se *se = &mas->se;
159	u32 m_irq, m_irq_en;
160
161	if (!mas->abort_failed)
162		return false;
163
164	/*
165	 * The only known case where a transfer times out and then a cancel
166	 * times out then an abort times out is if something is blocking our
167	 * interrupt handler from running.  Avoid starting any new transfers
168	 * until that sorts itself out.
169	 */
170	spin_lock_irq(&mas->lock);
171	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
172	m_irq_en = readl(se->base + SE_GENI_M_IRQ_EN);
173	spin_unlock_irq(&mas->lock);
174
175	if (m_irq & m_irq_en) {
176		dev_err(mas->dev, "Interrupts pending after abort: %#010x\n",
177			m_irq & m_irq_en);
178		return true;
179	}
180
181	/*
182	 * If we're here the problem resolved itself so no need to check more
183	 * on future transfers.
184	 */
185	mas->abort_failed = false;
186
187	return false;
188}
189
190static void spi_geni_set_cs(struct spi_device *slv, bool set_flag)
191{
192	struct spi_geni_master *mas = spi_master_get_devdata(slv->master);
193	struct spi_master *spi = dev_get_drvdata(mas->dev);
194	struct geni_se *se = &mas->se;
195	unsigned long time_left;
196
197	if (!(slv->mode & SPI_CS_HIGH))
198		set_flag = !set_flag;
199
200	if (set_flag == mas->cs_flag)
201		return;
202
203	pm_runtime_get_sync(mas->dev);
204
205	if (spi_geni_is_abort_still_pending(mas)) {
206		dev_err(mas->dev, "Can't set chip select\n");
207		goto exit;
208	}
209
210	mas->cs_flag = set_flag;
211
212	spin_lock_irq(&mas->lock);
213	reinit_completion(&mas->cs_done);
214	if (set_flag)
215		geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);
216	else
217		geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0);
218	spin_unlock_irq(&mas->lock);
219
220	time_left = wait_for_completion_timeout(&mas->cs_done, HZ);
221	if (!time_left)
222		handle_fifo_timeout(spi, NULL);
223
224exit:
225	pm_runtime_put(mas->dev);
226}
227
228static void spi_setup_word_len(struct spi_geni_master *mas, u16 mode,
229					unsigned int bits_per_word)
230{
231	unsigned int pack_words;
232	bool msb_first = (mode & SPI_LSB_FIRST) ? false : true;
233	struct geni_se *se = &mas->se;
234	u32 word_len;
235
236	/*
237	 * If bits_per_word isn't a byte aligned value, set the packing to be
238	 * 1 SPI word per FIFO word.
239	 */
240	if (!(mas->fifo_width_bits % bits_per_word))
241		pack_words = mas->fifo_width_bits / bits_per_word;
242	else
243		pack_words = 1;
244	geni_se_config_packing(&mas->se, bits_per_word, pack_words, msb_first,
245								true, true);
246	word_len = (bits_per_word - MIN_WORD_LEN) & WORD_LEN_MSK;
247	writel(word_len, se->base + SE_SPI_WORD_LEN);
248}
249
250static int geni_spi_set_clock_and_bw(struct spi_geni_master *mas,
251					unsigned long clk_hz)
252{
253	u32 clk_sel, m_clk_cfg, idx, div;
254	struct geni_se *se = &mas->se;
255	int ret;
256
257	if (clk_hz == mas->cur_speed_hz)
258		return 0;
259
260	ret = get_spi_clk_cfg(clk_hz, mas, &idx, &div);
261	if (ret) {
262		dev_err(mas->dev, "Err setting clk to %lu: %d\n", clk_hz, ret);
263		return ret;
264	}
265
266	/*
267	 * SPI core clock gets configured with the requested frequency
268	 * or the frequency closer to the requested frequency.
269	 * For that reason requested frequency is stored in the
270	 * cur_speed_hz and referred in the consecutive transfer instead
271	 * of calling clk_get_rate() API.
272	 */
273	mas->cur_speed_hz = clk_hz;
274
275	clk_sel = idx & CLK_SEL_MSK;
276	m_clk_cfg = (div << CLK_DIV_SHFT) | SER_CLK_EN;
277	writel(clk_sel, se->base + SE_GENI_CLK_SEL);
278	writel(m_clk_cfg, se->base + GENI_SER_M_CLK_CFG);
279
280	/* Set BW quota for CPU as driver supports FIFO mode only. */
281	se->icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(mas->cur_speed_hz);
282	ret = geni_icc_set_bw(se);
283	if (ret)
284		return ret;
285
286	return 0;
287}
288
289static int setup_fifo_params(struct spi_device *spi_slv,
290					struct spi_master *spi)
291{
292	struct spi_geni_master *mas = spi_master_get_devdata(spi);
293	struct geni_se *se = &mas->se;
294	u32 loopback_cfg = 0, cpol = 0, cpha = 0, demux_output_inv = 0;
295	u32 demux_sel;
296
297	if (mas->last_mode != spi_slv->mode) {
298		if (spi_slv->mode & SPI_LOOP)
299			loopback_cfg = LOOPBACK_ENABLE;
300
301		if (spi_slv->mode & SPI_CPOL)
302			cpol = CPOL;
303
304		if (spi_slv->mode & SPI_CPHA)
305			cpha = CPHA;
306
307		if (spi_slv->mode & SPI_CS_HIGH)
308			demux_output_inv = BIT(spi_slv->chip_select);
309
310		demux_sel = spi_slv->chip_select;
311		mas->cur_bits_per_word = spi_slv->bits_per_word;
312
313		spi_setup_word_len(mas, spi_slv->mode, spi_slv->bits_per_word);
314		writel(loopback_cfg, se->base + SE_SPI_LOOPBACK);
315		writel(demux_sel, se->base + SE_SPI_DEMUX_SEL);
316		writel(cpha, se->base + SE_SPI_CPHA);
317		writel(cpol, se->base + SE_SPI_CPOL);
318		writel(demux_output_inv, se->base + SE_SPI_DEMUX_OUTPUT_INV);
319
320		mas->last_mode = spi_slv->mode;
321	}
322
323	return geni_spi_set_clock_and_bw(mas, spi_slv->max_speed_hz);
324}
325
326static int spi_geni_prepare_message(struct spi_master *spi,
327					struct spi_message *spi_msg)
328{
329	int ret;
330	struct spi_geni_master *mas = spi_master_get_devdata(spi);
331
332	if (spi_geni_is_abort_still_pending(mas))
333		return -EBUSY;
334
335	ret = setup_fifo_params(spi_msg->spi, spi);
336	if (ret)
337		dev_err(mas->dev, "Couldn't select mode %d\n", ret);
338	return ret;
339}
340
341static int spi_geni_init(struct spi_geni_master *mas)
342{
343	struct geni_se *se = &mas->se;
344	unsigned int proto, major, minor, ver;
345	u32 spi_tx_cfg;
346
347	pm_runtime_get_sync(mas->dev);
348
349	proto = geni_se_read_proto(se);
350	if (proto != GENI_SE_SPI) {
351		dev_err(mas->dev, "Invalid proto %d\n", proto);
352		pm_runtime_put(mas->dev);
353		return -ENXIO;
354	}
355	mas->tx_fifo_depth = geni_se_get_tx_fifo_depth(se);
356
357	/* Width of Tx and Rx FIFO is same */
358	mas->fifo_width_bits = geni_se_get_tx_fifo_width(se);
359
360	/*
361	 * Hardware programming guide suggests to configure
362	 * RX FIFO RFR level to fifo_depth-2.
363	 */
364	geni_se_init(se, mas->tx_fifo_depth - 3, mas->tx_fifo_depth - 2);
365	/* Transmit an entire FIFO worth of data per IRQ */
366	mas->tx_wm = 1;
367	ver = geni_se_get_qup_hw_version(se);
368	major = GENI_SE_VERSION_MAJOR(ver);
369	minor = GENI_SE_VERSION_MINOR(ver);
370
371	if (major == 1 && minor == 0)
372		mas->oversampling = 2;
373	else
374		mas->oversampling = 1;
375
376	geni_se_select_mode(se, GENI_SE_FIFO);
377
378	/* We always control CS manually */
379	spi_tx_cfg = readl(se->base + SE_SPI_TRANS_CFG);
380	spi_tx_cfg &= ~CS_TOGGLE;
381	writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG);
382
383	pm_runtime_put(mas->dev);
384	return 0;
385}
386
387static unsigned int geni_byte_per_fifo_word(struct spi_geni_master *mas)
388{
389	/*
390	 * Calculate how many bytes we'll put in each FIFO word.  If the
391	 * transfer words don't pack cleanly into a FIFO word we'll just put
392	 * one transfer word in each FIFO word.  If they do pack we'll pack 'em.
393	 */
394	if (mas->fifo_width_bits % mas->cur_bits_per_word)
395		return roundup_pow_of_two(DIV_ROUND_UP(mas->cur_bits_per_word,
396						       BITS_PER_BYTE));
397
398	return mas->fifo_width_bits / BITS_PER_BYTE;
399}
400
401static bool geni_spi_handle_tx(struct spi_geni_master *mas)
402{
403	struct geni_se *se = &mas->se;
404	unsigned int max_bytes;
405	const u8 *tx_buf;
406	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
407	unsigned int i = 0;
408
409	/* Stop the watermark IRQ if nothing to send */
410	if (!mas->cur_xfer) {
411		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
412		return false;
413	}
414
415	max_bytes = (mas->tx_fifo_depth - mas->tx_wm) * bytes_per_fifo_word;
416	if (mas->tx_rem_bytes < max_bytes)
417		max_bytes = mas->tx_rem_bytes;
418
419	tx_buf = mas->cur_xfer->tx_buf + mas->cur_xfer->len - mas->tx_rem_bytes;
420	while (i < max_bytes) {
421		unsigned int j;
422		unsigned int bytes_to_write;
423		u32 fifo_word = 0;
424		u8 *fifo_byte = (u8 *)&fifo_word;
425
426		bytes_to_write = min(bytes_per_fifo_word, max_bytes - i);
427		for (j = 0; j < bytes_to_write; j++)
428			fifo_byte[j] = tx_buf[i++];
429		iowrite32_rep(se->base + SE_GENI_TX_FIFOn, &fifo_word, 1);
430	}
431	mas->tx_rem_bytes -= max_bytes;
432	if (!mas->tx_rem_bytes) {
433		writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
434		return false;
435	}
436	return true;
437}
438
439static void geni_spi_handle_rx(struct spi_geni_master *mas)
440{
441	struct geni_se *se = &mas->se;
442	u32 rx_fifo_status;
443	unsigned int rx_bytes;
444	unsigned int rx_last_byte_valid;
445	u8 *rx_buf;
446	unsigned int bytes_per_fifo_word = geni_byte_per_fifo_word(mas);
447	unsigned int i = 0;
448
449	rx_fifo_status = readl(se->base + SE_GENI_RX_FIFO_STATUS);
450	rx_bytes = (rx_fifo_status & RX_FIFO_WC_MSK) * bytes_per_fifo_word;
451	if (rx_fifo_status & RX_LAST) {
452		rx_last_byte_valid = rx_fifo_status & RX_LAST_BYTE_VALID_MSK;
453		rx_last_byte_valid >>= RX_LAST_BYTE_VALID_SHFT;
454		if (rx_last_byte_valid && rx_last_byte_valid < 4)
455			rx_bytes -= bytes_per_fifo_word - rx_last_byte_valid;
456	}
457
458	/* Clear out the FIFO and bail if nowhere to put it */
459	if (!mas->cur_xfer) {
460		for (i = 0; i < DIV_ROUND_UP(rx_bytes, bytes_per_fifo_word); i++)
461			readl(se->base + SE_GENI_RX_FIFOn);
462		return;
463	}
464
465	if (mas->rx_rem_bytes < rx_bytes)
466		rx_bytes = mas->rx_rem_bytes;
467
468	rx_buf = mas->cur_xfer->rx_buf + mas->cur_xfer->len - mas->rx_rem_bytes;
469	while (i < rx_bytes) {
470		u32 fifo_word = 0;
471		u8 *fifo_byte = (u8 *)&fifo_word;
472		unsigned int bytes_to_read;
473		unsigned int j;
474
475		bytes_to_read = min(bytes_per_fifo_word, rx_bytes - i);
476		ioread32_rep(se->base + SE_GENI_RX_FIFOn, &fifo_word, 1);
477		for (j = 0; j < bytes_to_read; j++)
478			rx_buf[i++] = fifo_byte[j];
479	}
480	mas->rx_rem_bytes -= rx_bytes;
481}
482
483static void setup_fifo_xfer(struct spi_transfer *xfer,
484				struct spi_geni_master *mas,
485				u16 mode, struct spi_master *spi)
486{
487	u32 m_cmd = 0;
488	u32 len;
489	struct geni_se *se = &mas->se;
490	int ret;
491
492	/*
493	 * Ensure that our interrupt handler isn't still running from some
494	 * prior command before we start messing with the hardware behind
495	 * its back.  We don't need to _keep_ the lock here since we're only
496	 * worried about racing with out interrupt handler.  The SPI core
497	 * already handles making sure that we're not trying to do two
498	 * transfers at once or setting a chip select and doing a transfer
499	 * concurrently.
500	 *
501	 * NOTE: we actually _can't_ hold the lock here because possibly we
502	 * might call clk_set_rate() which needs to be able to sleep.
503	 */
504	spin_lock_irq(&mas->lock);
505	spin_unlock_irq(&mas->lock);
506
507	if (xfer->bits_per_word != mas->cur_bits_per_word) {
508		spi_setup_word_len(mas, mode, xfer->bits_per_word);
509		mas->cur_bits_per_word = xfer->bits_per_word;
510	}
511
512	/* Speed and bits per word can be overridden per transfer */
513	ret = geni_spi_set_clock_and_bw(mas, xfer->speed_hz);
514	if (ret)
515		return;
516
517	mas->tx_rem_bytes = 0;
518	mas->rx_rem_bytes = 0;
519
520	if (!(mas->cur_bits_per_word % MIN_WORD_LEN))
521		len = xfer->len * BITS_PER_BYTE / mas->cur_bits_per_word;
522	else
523		len = xfer->len / (mas->cur_bits_per_word / BITS_PER_BYTE + 1);
524	len &= TRANS_LEN_MSK;
525
526	mas->cur_xfer = xfer;
527	if (xfer->tx_buf) {
528		m_cmd |= SPI_TX_ONLY;
529		mas->tx_rem_bytes = xfer->len;
530		writel(len, se->base + SE_SPI_TX_TRANS_LEN);
531	}
532
533	if (xfer->rx_buf) {
534		m_cmd |= SPI_RX_ONLY;
535		writel(len, se->base + SE_SPI_RX_TRANS_LEN);
536		mas->rx_rem_bytes = xfer->len;
537	}
538
539	/*
540	 * Lock around right before we start the transfer since our
541	 * interrupt could come in at any time now.
542	 */
543	spin_lock_irq(&mas->lock);
544	geni_se_setup_m_cmd(se, m_cmd, FRAGMENTATION);
545
546	/*
547	 * TX_WATERMARK_REG should be set after SPI configuration and
548	 * setting up GENI SE engine, as driver starts data transfer
549	 * for the watermark interrupt.
550	 */
551	if (m_cmd & SPI_TX_ONLY) {
552		if (geni_spi_handle_tx(mas))
553			writel(mas->tx_wm, se->base + SE_GENI_TX_WATERMARK_REG);
554	}
555	spin_unlock_irq(&mas->lock);
556}
557
558static int spi_geni_transfer_one(struct spi_master *spi,
559				struct spi_device *slv,
560				struct spi_transfer *xfer)
561{
562	struct spi_geni_master *mas = spi_master_get_devdata(spi);
563
564	if (spi_geni_is_abort_still_pending(mas))
565		return -EBUSY;
566
567	/* Terminate and return success for 0 byte length transfer */
568	if (!xfer->len)
569		return 0;
570
571	setup_fifo_xfer(xfer, mas, slv->mode, spi);
572	return 1;
573}
574
575static irqreturn_t geni_spi_isr(int irq, void *data)
576{
577	struct spi_master *spi = data;
578	struct spi_geni_master *mas = spi_master_get_devdata(spi);
579	struct geni_se *se = &mas->se;
580	u32 m_irq;
581
582	m_irq = readl(se->base + SE_GENI_M_IRQ_STATUS);
583	if (!m_irq)
584		return IRQ_NONE;
585
586	if (m_irq & (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |
587		     M_RX_FIFO_RD_ERR_EN | M_RX_FIFO_WR_ERR_EN |
588		     M_TX_FIFO_RD_ERR_EN | M_TX_FIFO_WR_ERR_EN))
589		dev_warn(mas->dev, "Unexpected IRQ err status %#010x\n", m_irq);
590
591	spin_lock(&mas->lock);
592
593	if ((m_irq & M_RX_FIFO_WATERMARK_EN) || (m_irq & M_RX_FIFO_LAST_EN))
594		geni_spi_handle_rx(mas);
595
596	if (m_irq & M_TX_FIFO_WATERMARK_EN)
597		geni_spi_handle_tx(mas);
598
599	if (m_irq & M_CMD_DONE_EN) {
600		if (mas->cur_xfer) {
601			spi_finalize_current_transfer(spi);
602			mas->cur_xfer = NULL;
603			/*
604			 * If this happens, then a CMD_DONE came before all the
605			 * Tx buffer bytes were sent out. This is unusual, log
606			 * this condition and disable the WM interrupt to
607			 * prevent the system from stalling due an interrupt
608			 * storm.
609			 *
610			 * If this happens when all Rx bytes haven't been
611			 * received, log the condition. The only known time
612			 * this can happen is if bits_per_word != 8 and some
613			 * registers that expect xfer lengths in num spi_words
614			 * weren't written correctly.
615			 */
616			if (mas->tx_rem_bytes) {
617				writel(0, se->base + SE_GENI_TX_WATERMARK_REG);
618				dev_err(mas->dev, "Premature done. tx_rem = %d bpw%d\n",
619					mas->tx_rem_bytes, mas->cur_bits_per_word);
620			}
621			if (mas->rx_rem_bytes)
622				dev_err(mas->dev, "Premature done. rx_rem = %d bpw%d\n",
623					mas->rx_rem_bytes, mas->cur_bits_per_word);
624		} else {
625			complete(&mas->cs_done);
626		}
627	}
628
629	if (m_irq & M_CMD_CANCEL_EN)
630		complete(&mas->cancel_done);
631	if (m_irq & M_CMD_ABORT_EN)
632		complete(&mas->abort_done);
633
634	/*
635	 * It's safe or a good idea to Ack all of our our interrupts at the
636	 * end of the function. Specifically:
637	 * - M_CMD_DONE_EN / M_RX_FIFO_LAST_EN: Edge triggered interrupts and
638	 *   clearing Acks. Clearing at the end relies on nobody else having
639	 *   started a new transfer yet or else we could be clearing _their_
640	 *   done bit, but everyone grabs the spinlock before starting a new
641	 *   transfer.
642	 * - M_RX_FIFO_WATERMARK_EN / M_TX_FIFO_WATERMARK_EN: These appear
643	 *   to be "latched level" interrupts so it's important to clear them
644	 *   _after_ you've handled the condition and always safe to do so
645	 *   since they'll re-assert if they're still happening.
646	 */
647	writel(m_irq, se->base + SE_GENI_M_IRQ_CLEAR);
648
649	spin_unlock(&mas->lock);
650
651	return IRQ_HANDLED;
652}
653
654static int spi_geni_probe(struct platform_device *pdev)
655{
656	int ret, irq;
657	struct spi_master *spi;
658	struct spi_geni_master *mas;
659	void __iomem *base;
660	struct clk *clk;
661	struct device *dev = &pdev->dev;
662
663	irq = platform_get_irq(pdev, 0);
664	if (irq < 0)
665		return irq;
666
667	base = devm_platform_ioremap_resource(pdev, 0);
668	if (IS_ERR(base))
669		return PTR_ERR(base);
670
671	clk = devm_clk_get(dev, "se");
672	if (IS_ERR(clk))
673		return PTR_ERR(clk);
674
675	spi = devm_spi_alloc_master(dev, sizeof(*mas));
676	if (!spi)
677		return -ENOMEM;
678
679	platform_set_drvdata(pdev, spi);
680	mas = spi_master_get_devdata(spi);
681	mas->irq = irq;
682	mas->dev = dev;
683	mas->se.dev = dev;
684	mas->se.wrapper = dev_get_drvdata(dev->parent);
685	mas->se.base = base;
686	mas->se.clk = clk;
687	mas->se.opp_table = dev_pm_opp_set_clkname(&pdev->dev, "se");
688	if (IS_ERR(mas->se.opp_table))
689		return PTR_ERR(mas->se.opp_table);
690	/* OPP table is optional */
691	ret = dev_pm_opp_of_add_table(&pdev->dev);
692	if (ret && ret != -ENODEV) {
693		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
694		goto put_clkname;
695	}
696
697	spi->bus_num = -1;
698	spi->dev.of_node = dev->of_node;
699	spi->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_CS_HIGH;
700	spi->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
701	spi->num_chipselect = 4;
702	spi->max_speed_hz = 50000000;
703	spi->prepare_message = spi_geni_prepare_message;
704	spi->transfer_one = spi_geni_transfer_one;
705	spi->auto_runtime_pm = true;
706	spi->handle_err = handle_fifo_timeout;
707	spi->set_cs = spi_geni_set_cs;
708
709	init_completion(&mas->cs_done);
710	init_completion(&mas->cancel_done);
711	init_completion(&mas->abort_done);
712	spin_lock_init(&mas->lock);
713	pm_runtime_use_autosuspend(&pdev->dev);
714	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
715	pm_runtime_enable(dev);
716
717	ret = geni_icc_get(&mas->se, NULL);
718	if (ret)
719		goto spi_geni_probe_runtime_disable;
720	/* Set the bus quota to a reasonable value for register access */
721	mas->se.icc_paths[GENI_TO_CORE].avg_bw = Bps_to_icc(CORE_2X_50_MHZ);
722	mas->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
723
724	ret = geni_icc_set_bw(&mas->se);
725	if (ret)
726		goto spi_geni_probe_runtime_disable;
727
728	ret = spi_geni_init(mas);
729	if (ret)
730		goto spi_geni_probe_runtime_disable;
731
732	ret = request_irq(mas->irq, geni_spi_isr, 0, dev_name(dev), spi);
733	if (ret)
734		goto spi_geni_probe_runtime_disable;
735
736	ret = spi_register_master(spi);
737	if (ret)
738		goto spi_geni_probe_free_irq;
739
740	return 0;
741spi_geni_probe_free_irq:
742	free_irq(mas->irq, spi);
743spi_geni_probe_runtime_disable:
744	pm_runtime_disable(dev);
745	dev_pm_opp_of_remove_table(&pdev->dev);
746put_clkname:
747	dev_pm_opp_put_clkname(mas->se.opp_table);
748	return ret;
749}
750
751static int spi_geni_remove(struct platform_device *pdev)
752{
753	struct spi_master *spi = platform_get_drvdata(pdev);
754	struct spi_geni_master *mas = spi_master_get_devdata(spi);
755
756	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
757	spi_unregister_master(spi);
758
759	free_irq(mas->irq, spi);
760	pm_runtime_disable(&pdev->dev);
761	dev_pm_opp_of_remove_table(&pdev->dev);
762	dev_pm_opp_put_clkname(mas->se.opp_table);
763	return 0;
764}
765
766static int __maybe_unused spi_geni_runtime_suspend(struct device *dev)
767{
768	struct spi_master *spi = dev_get_drvdata(dev);
769	struct spi_geni_master *mas = spi_master_get_devdata(spi);
770	int ret;
771
772	/* Drop the performance state vote */
773	dev_pm_opp_set_rate(dev, 0);
774
775	ret = geni_se_resources_off(&mas->se);
776	if (ret)
777		return ret;
778
779	return geni_icc_disable(&mas->se);
780}
781
782static int __maybe_unused spi_geni_runtime_resume(struct device *dev)
783{
784	struct spi_master *spi = dev_get_drvdata(dev);
785	struct spi_geni_master *mas = spi_master_get_devdata(spi);
786	int ret;
787
788	ret = geni_icc_enable(&mas->se);
789	if (ret)
790		return ret;
791
792	ret = geni_se_resources_on(&mas->se);
793	if (ret)
794		return ret;
795
796	return dev_pm_opp_set_rate(mas->dev, mas->cur_sclk_hz);
797}
798
799static int __maybe_unused spi_geni_suspend(struct device *dev)
800{
801	struct spi_master *spi = dev_get_drvdata(dev);
802	int ret;
803
804	ret = spi_master_suspend(spi);
805	if (ret)
806		return ret;
807
808	ret = pm_runtime_force_suspend(dev);
809	if (ret)
810		spi_master_resume(spi);
811
812	return ret;
813}
814
815static int __maybe_unused spi_geni_resume(struct device *dev)
816{
817	struct spi_master *spi = dev_get_drvdata(dev);
818	int ret;
819
820	ret = pm_runtime_force_resume(dev);
821	if (ret)
822		return ret;
823
824	ret = spi_master_resume(spi);
825	if (ret)
826		pm_runtime_force_suspend(dev);
827
828	return ret;
829}
830
831static const struct dev_pm_ops spi_geni_pm_ops = {
832	SET_RUNTIME_PM_OPS(spi_geni_runtime_suspend,
833					spi_geni_runtime_resume, NULL)
834	SET_SYSTEM_SLEEP_PM_OPS(spi_geni_suspend, spi_geni_resume)
835};
836
837static const struct of_device_id spi_geni_dt_match[] = {
838	{ .compatible = "qcom,geni-spi" },
839	{}
840};
841MODULE_DEVICE_TABLE(of, spi_geni_dt_match);
842
843static struct platform_driver spi_geni_driver = {
844	.probe  = spi_geni_probe,
845	.remove = spi_geni_remove,
846	.driver = {
847		.name = "geni_spi",
848		.pm = &spi_geni_pm_ops,
849		.of_match_table = spi_geni_dt_match,
850	},
851};
852module_platform_driver(spi_geni_driver);
853
854MODULE_DESCRIPTION("SPI driver for GENI based QUP cores");
855MODULE_LICENSE("GPL v2");
856