xref: /openbmc/linux/drivers/spi/spi-mt65xx.c (revision d5771670)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015 MediaTek Inc.
4  * Author: Leilk Liu <leilk.liu@mediatek.com>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/device.h>
9 #include <linux/err.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/ioport.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/platform_device.h>
17 #include <linux/platform_data/spi-mt65xx.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/spi/spi.h>
20 #include <linux/dma-mapping.h>
21 
22 #define SPI_CFG0_REG                      0x0000
23 #define SPI_CFG1_REG                      0x0004
24 #define SPI_TX_SRC_REG                    0x0008
25 #define SPI_RX_DST_REG                    0x000c
26 #define SPI_TX_DATA_REG                   0x0010
27 #define SPI_RX_DATA_REG                   0x0014
28 #define SPI_CMD_REG                       0x0018
29 #define SPI_STATUS0_REG                   0x001c
30 #define SPI_PAD_SEL_REG                   0x0024
31 #define SPI_CFG2_REG                      0x0028
32 #define SPI_TX_SRC_REG_64                 0x002c
33 #define SPI_RX_DST_REG_64                 0x0030
34 #define SPI_CFG3_IPM_REG                  0x0040
35 
36 #define SPI_CFG0_SCK_HIGH_OFFSET          0
37 #define SPI_CFG0_SCK_LOW_OFFSET           8
38 #define SPI_CFG0_CS_HOLD_OFFSET           16
39 #define SPI_CFG0_CS_SETUP_OFFSET          24
40 #define SPI_ADJUST_CFG0_CS_HOLD_OFFSET    0
41 #define SPI_ADJUST_CFG0_CS_SETUP_OFFSET   16
42 
43 #define SPI_CFG1_CS_IDLE_OFFSET           0
44 #define SPI_CFG1_PACKET_LOOP_OFFSET       8
45 #define SPI_CFG1_PACKET_LENGTH_OFFSET     16
46 #define SPI_CFG1_GET_TICK_DLY_OFFSET      29
47 #define SPI_CFG1_GET_TICK_DLY_OFFSET_V1   30
48 
49 #define SPI_CFG1_GET_TICK_DLY_MASK        0xe0000000
50 #define SPI_CFG1_GET_TICK_DLY_MASK_V1     0xc0000000
51 
52 #define SPI_CFG1_CS_IDLE_MASK             0xff
53 #define SPI_CFG1_PACKET_LOOP_MASK         0xff00
54 #define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
55 #define SPI_CFG1_IPM_PACKET_LENGTH_MASK   GENMASK(31, 16)
56 #define SPI_CFG2_SCK_HIGH_OFFSET          0
57 #define SPI_CFG2_SCK_LOW_OFFSET           16
58 
59 #define SPI_CMD_ACT                  BIT(0)
60 #define SPI_CMD_RESUME               BIT(1)
61 #define SPI_CMD_RST                  BIT(2)
62 #define SPI_CMD_PAUSE_EN             BIT(4)
63 #define SPI_CMD_DEASSERT             BIT(5)
64 #define SPI_CMD_SAMPLE_SEL           BIT(6)
65 #define SPI_CMD_CS_POL               BIT(7)
66 #define SPI_CMD_CPHA                 BIT(8)
67 #define SPI_CMD_CPOL                 BIT(9)
68 #define SPI_CMD_RX_DMA               BIT(10)
69 #define SPI_CMD_TX_DMA               BIT(11)
70 #define SPI_CMD_TXMSBF               BIT(12)
71 #define SPI_CMD_RXMSBF               BIT(13)
72 #define SPI_CMD_RX_ENDIAN            BIT(14)
73 #define SPI_CMD_TX_ENDIAN            BIT(15)
74 #define SPI_CMD_FINISH_IE            BIT(16)
75 #define SPI_CMD_PAUSE_IE             BIT(17)
76 #define SPI_CMD_IPM_NONIDLE_MODE     BIT(19)
77 #define SPI_CMD_IPM_SPIM_LOOP        BIT(21)
78 #define SPI_CMD_IPM_GET_TICKDLY_OFFSET    22
79 
80 #define SPI_CMD_IPM_GET_TICKDLY_MASK	GENMASK(24, 22)
81 #define SPI_CFG3_IPM_HALF_DUPLEX_DIR		BIT(2)
82 #define SPI_CFG3_IPM_HALF_DUPLEX_EN		BIT(3)
83 #define MT8173_SPI_MAX_PAD_SEL 3
84 
85 #define MTK_SPI_PAUSE_INT_STATUS 0x2
86 
87 #define MTK_SPI_IDLE 0
88 #define MTK_SPI_PAUSED 1
89 
90 #define MTK_SPI_MAX_FIFO_SIZE 32U
91 #define MTK_SPI_PACKET_SIZE 1024
92 #define MTK_SPI_IPM_PACKET_SIZE SZ_64K
93 #define MTK_SPI_32BITS_MASK  (0xffffffff)
94 
95 #define DMA_ADDR_EXT_BITS (36)
96 #define DMA_ADDR_DEF_BITS (32)
97 
98 struct mtk_spi_compatible {
99 	bool need_pad_sel;
100 	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
101 	bool must_tx;
102 	/* some IC design adjust cfg register to enhance time accuracy */
103 	bool enhance_timing;
104 	/* some IC support DMA addr extension */
105 	bool dma_ext;
106 	/* some IC no need unprepare SPI clk */
107 	bool no_need_unprepare;
108 	/* IPM design adjust and extend register to support more features */
109 	bool ipm_design;
110 
111 };
112 
113 struct mtk_spi {
114 	void __iomem *base;
115 	u32 state;
116 	int pad_num;
117 	u32 *pad_sel;
118 	struct clk *parent_clk, *sel_clk, *spi_clk;
119 	struct spi_transfer *cur_transfer;
120 	u32 xfer_len;
121 	u32 num_xfered;
122 	struct scatterlist *tx_sgl, *rx_sgl;
123 	u32 tx_sgl_len, rx_sgl_len;
124 	const struct mtk_spi_compatible *dev_comp;
125 	u32 spi_clk_hz;
126 };
127 
128 static const struct mtk_spi_compatible mtk_common_compat;
129 
130 static const struct mtk_spi_compatible mt2712_compat = {
131 	.must_tx = true,
132 };
133 
134 static const struct mtk_spi_compatible mtk_ipm_compat = {
135 	.enhance_timing = true,
136 	.dma_ext = true,
137 	.ipm_design = true,
138 };
139 
140 static const struct mtk_spi_compatible mt6765_compat = {
141 	.need_pad_sel = true,
142 	.must_tx = true,
143 	.enhance_timing = true,
144 	.dma_ext = true,
145 };
146 
147 static const struct mtk_spi_compatible mt7622_compat = {
148 	.must_tx = true,
149 	.enhance_timing = true,
150 };
151 
152 static const struct mtk_spi_compatible mt8173_compat = {
153 	.need_pad_sel = true,
154 	.must_tx = true,
155 };
156 
157 static const struct mtk_spi_compatible mt8183_compat = {
158 	.need_pad_sel = true,
159 	.must_tx = true,
160 	.enhance_timing = true,
161 };
162 
163 static const struct mtk_spi_compatible mt6893_compat = {
164 	.need_pad_sel = true,
165 	.must_tx = true,
166 	.enhance_timing = true,
167 	.dma_ext = true,
168 	.no_need_unprepare = true,
169 };
170 
171 /*
172  * A piece of default chip info unless the platform
173  * supplies it.
174  */
175 static const struct mtk_chip_config mtk_default_chip_info = {
176 	.sample_sel = 0,
177 	.tick_delay = 0,
178 };
179 
180 static const struct of_device_id mtk_spi_of_match[] = {
181 	{ .compatible = "mediatek,spi-ipm",
182 		.data = (void *)&mtk_ipm_compat,
183 	},
184 	{ .compatible = "mediatek,mt2701-spi",
185 		.data = (void *)&mtk_common_compat,
186 	},
187 	{ .compatible = "mediatek,mt2712-spi",
188 		.data = (void *)&mt2712_compat,
189 	},
190 	{ .compatible = "mediatek,mt6589-spi",
191 		.data = (void *)&mtk_common_compat,
192 	},
193 	{ .compatible = "mediatek,mt6765-spi",
194 		.data = (void *)&mt6765_compat,
195 	},
196 	{ .compatible = "mediatek,mt7622-spi",
197 		.data = (void *)&mt7622_compat,
198 	},
199 	{ .compatible = "mediatek,mt7629-spi",
200 		.data = (void *)&mt7622_compat,
201 	},
202 	{ .compatible = "mediatek,mt8135-spi",
203 		.data = (void *)&mtk_common_compat,
204 	},
205 	{ .compatible = "mediatek,mt8173-spi",
206 		.data = (void *)&mt8173_compat,
207 	},
208 	{ .compatible = "mediatek,mt8183-spi",
209 		.data = (void *)&mt8183_compat,
210 	},
211 	{ .compatible = "mediatek,mt8192-spi",
212 		.data = (void *)&mt6765_compat,
213 	},
214 	{ .compatible = "mediatek,mt6893-spi",
215 		.data = (void *)&mt6893_compat,
216 	},
217 	{}
218 };
219 MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
220 
221 static void mtk_spi_reset(struct mtk_spi *mdata)
222 {
223 	u32 reg_val;
224 
225 	/* set the software reset bit in SPI_CMD_REG. */
226 	reg_val = readl(mdata->base + SPI_CMD_REG);
227 	reg_val |= SPI_CMD_RST;
228 	writel(reg_val, mdata->base + SPI_CMD_REG);
229 
230 	reg_val = readl(mdata->base + SPI_CMD_REG);
231 	reg_val &= ~SPI_CMD_RST;
232 	writel(reg_val, mdata->base + SPI_CMD_REG);
233 }
234 
235 static int mtk_spi_set_hw_cs_timing(struct spi_device *spi)
236 {
237 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
238 	struct spi_delay *cs_setup = &spi->cs_setup;
239 	struct spi_delay *cs_hold = &spi->cs_hold;
240 	struct spi_delay *cs_inactive = &spi->cs_inactive;
241 	u32 setup, hold, inactive;
242 	u32 reg_val;
243 	int delay;
244 
245 	delay = spi_delay_to_ns(cs_setup, NULL);
246 	if (delay < 0)
247 		return delay;
248 	setup = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
249 
250 	delay = spi_delay_to_ns(cs_hold, NULL);
251 	if (delay < 0)
252 		return delay;
253 	hold = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
254 
255 	delay = spi_delay_to_ns(cs_inactive, NULL);
256 	if (delay < 0)
257 		return delay;
258 	inactive = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
259 
260 	if (hold || setup) {
261 		reg_val = readl(mdata->base + SPI_CFG0_REG);
262 		if (mdata->dev_comp->enhance_timing) {
263 			if (hold) {
264 				hold = min_t(u32, hold, 0x10000);
265 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
266 				reg_val |= (((hold - 1) & 0xffff)
267 					<< SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
268 			}
269 			if (setup) {
270 				setup = min_t(u32, setup, 0x10000);
271 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
272 				reg_val |= (((setup - 1) & 0xffff)
273 					<< SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
274 			}
275 		} else {
276 			if (hold) {
277 				hold = min_t(u32, hold, 0x100);
278 				reg_val &= ~(0xff << SPI_CFG0_CS_HOLD_OFFSET);
279 				reg_val |= (((hold - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
280 			}
281 			if (setup) {
282 				setup = min_t(u32, setup, 0x100);
283 				reg_val &= ~(0xff << SPI_CFG0_CS_SETUP_OFFSET);
284 				reg_val |= (((setup - 1) & 0xff)
285 					<< SPI_CFG0_CS_SETUP_OFFSET);
286 			}
287 		}
288 		writel(reg_val, mdata->base + SPI_CFG0_REG);
289 	}
290 
291 	if (inactive) {
292 		inactive = min_t(u32, inactive, 0x100);
293 		reg_val = readl(mdata->base + SPI_CFG1_REG);
294 		reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
295 		reg_val |= (((inactive - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
296 		writel(reg_val, mdata->base + SPI_CFG1_REG);
297 	}
298 
299 	return 0;
300 }
301 
302 static int mtk_spi_hw_init(struct spi_master *master,
303 			   struct spi_device *spi)
304 {
305 	u16 cpha, cpol;
306 	u32 reg_val;
307 	struct mtk_chip_config *chip_config = spi->controller_data;
308 	struct mtk_spi *mdata = spi_master_get_devdata(master);
309 
310 	cpha = spi->mode & SPI_CPHA ? 1 : 0;
311 	cpol = spi->mode & SPI_CPOL ? 1 : 0;
312 
313 	reg_val = readl(mdata->base + SPI_CMD_REG);
314 	if (mdata->dev_comp->ipm_design) {
315 		/* SPI transfer without idle time until packet length done */
316 		reg_val |= SPI_CMD_IPM_NONIDLE_MODE;
317 		if (spi->mode & SPI_LOOP)
318 			reg_val |= SPI_CMD_IPM_SPIM_LOOP;
319 		else
320 			reg_val &= ~SPI_CMD_IPM_SPIM_LOOP;
321 	}
322 
323 	if (cpha)
324 		reg_val |= SPI_CMD_CPHA;
325 	else
326 		reg_val &= ~SPI_CMD_CPHA;
327 	if (cpol)
328 		reg_val |= SPI_CMD_CPOL;
329 	else
330 		reg_val &= ~SPI_CMD_CPOL;
331 
332 	/* set the mlsbx and mlsbtx */
333 	if (spi->mode & SPI_LSB_FIRST) {
334 		reg_val &= ~SPI_CMD_TXMSBF;
335 		reg_val &= ~SPI_CMD_RXMSBF;
336 	} else {
337 		reg_val |= SPI_CMD_TXMSBF;
338 		reg_val |= SPI_CMD_RXMSBF;
339 	}
340 
341 	/* set the tx/rx endian */
342 #ifdef __LITTLE_ENDIAN
343 	reg_val &= ~SPI_CMD_TX_ENDIAN;
344 	reg_val &= ~SPI_CMD_RX_ENDIAN;
345 #else
346 	reg_val |= SPI_CMD_TX_ENDIAN;
347 	reg_val |= SPI_CMD_RX_ENDIAN;
348 #endif
349 
350 	if (mdata->dev_comp->enhance_timing) {
351 		/* set CS polarity */
352 		if (spi->mode & SPI_CS_HIGH)
353 			reg_val |= SPI_CMD_CS_POL;
354 		else
355 			reg_val &= ~SPI_CMD_CS_POL;
356 
357 		if (chip_config->sample_sel)
358 			reg_val |= SPI_CMD_SAMPLE_SEL;
359 		else
360 			reg_val &= ~SPI_CMD_SAMPLE_SEL;
361 	}
362 
363 	/* set finish and pause interrupt always enable */
364 	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
365 
366 	/* disable dma mode */
367 	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
368 
369 	/* disable deassert mode */
370 	reg_val &= ~SPI_CMD_DEASSERT;
371 
372 	writel(reg_val, mdata->base + SPI_CMD_REG);
373 
374 	/* pad select */
375 	if (mdata->dev_comp->need_pad_sel)
376 		writel(mdata->pad_sel[spi->chip_select],
377 		       mdata->base + SPI_PAD_SEL_REG);
378 
379 	/* tick delay */
380 	if (mdata->dev_comp->enhance_timing) {
381 		if (mdata->dev_comp->ipm_design) {
382 			reg_val = readl(mdata->base + SPI_CMD_REG);
383 			reg_val &= ~SPI_CMD_IPM_GET_TICKDLY_MASK;
384 			reg_val |= ((chip_config->tick_delay & 0x7)
385 				    << SPI_CMD_IPM_GET_TICKDLY_OFFSET);
386 			writel(reg_val, mdata->base + SPI_CMD_REG);
387 		} else {
388 			reg_val = readl(mdata->base + SPI_CFG1_REG);
389 			reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK;
390 			reg_val |= ((chip_config->tick_delay & 0x7)
391 				    << SPI_CFG1_GET_TICK_DLY_OFFSET);
392 			writel(reg_val, mdata->base + SPI_CFG1_REG);
393 		}
394 	} else {
395 		reg_val = readl(mdata->base + SPI_CFG1_REG);
396 		reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK_V1;
397 		reg_val |= ((chip_config->tick_delay & 0x3)
398 			    << SPI_CFG1_GET_TICK_DLY_OFFSET_V1);
399 		writel(reg_val, mdata->base + SPI_CFG1_REG);
400 	}
401 
402 	/* set hw cs timing */
403 	mtk_spi_set_hw_cs_timing(spi);
404 	return 0;
405 }
406 
407 static int mtk_spi_prepare_message(struct spi_master *master,
408 				   struct spi_message *msg)
409 {
410 	return mtk_spi_hw_init(master, msg->spi);
411 }
412 
413 static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
414 {
415 	u32 reg_val;
416 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
417 
418 	if (spi->mode & SPI_CS_HIGH)
419 		enable = !enable;
420 
421 	reg_val = readl(mdata->base + SPI_CMD_REG);
422 	if (!enable) {
423 		reg_val |= SPI_CMD_PAUSE_EN;
424 		writel(reg_val, mdata->base + SPI_CMD_REG);
425 	} else {
426 		reg_val &= ~SPI_CMD_PAUSE_EN;
427 		writel(reg_val, mdata->base + SPI_CMD_REG);
428 		mdata->state = MTK_SPI_IDLE;
429 		mtk_spi_reset(mdata);
430 	}
431 }
432 
433 static void mtk_spi_prepare_transfer(struct spi_master *master,
434 				     u32 speed_hz)
435 {
436 	u32 div, sck_time, reg_val;
437 	struct mtk_spi *mdata = spi_master_get_devdata(master);
438 
439 	if (speed_hz < mdata->spi_clk_hz / 2)
440 		div = DIV_ROUND_UP(mdata->spi_clk_hz, speed_hz);
441 	else
442 		div = 1;
443 
444 	sck_time = (div + 1) / 2;
445 
446 	if (mdata->dev_comp->enhance_timing) {
447 		reg_val = readl(mdata->base + SPI_CFG2_REG);
448 		reg_val &= ~(0xffff << SPI_CFG2_SCK_HIGH_OFFSET);
449 		reg_val |= (((sck_time - 1) & 0xffff)
450 			   << SPI_CFG2_SCK_HIGH_OFFSET);
451 		reg_val &= ~(0xffff << SPI_CFG2_SCK_LOW_OFFSET);
452 		reg_val |= (((sck_time - 1) & 0xffff)
453 			   << SPI_CFG2_SCK_LOW_OFFSET);
454 		writel(reg_val, mdata->base + SPI_CFG2_REG);
455 	} else {
456 		reg_val = readl(mdata->base + SPI_CFG0_REG);
457 		reg_val &= ~(0xff << SPI_CFG0_SCK_HIGH_OFFSET);
458 		reg_val |= (((sck_time - 1) & 0xff)
459 			   << SPI_CFG0_SCK_HIGH_OFFSET);
460 		reg_val &= ~(0xff << SPI_CFG0_SCK_LOW_OFFSET);
461 		reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
462 		writel(reg_val, mdata->base + SPI_CFG0_REG);
463 	}
464 }
465 
466 static void mtk_spi_setup_packet(struct spi_master *master)
467 {
468 	u32 packet_size, packet_loop, reg_val;
469 	struct mtk_spi *mdata = spi_master_get_devdata(master);
470 
471 	if (mdata->dev_comp->ipm_design)
472 		packet_size = min_t(u32,
473 				    mdata->xfer_len,
474 				    MTK_SPI_IPM_PACKET_SIZE);
475 	else
476 		packet_size = min_t(u32,
477 				    mdata->xfer_len,
478 				    MTK_SPI_PACKET_SIZE);
479 
480 	packet_loop = mdata->xfer_len / packet_size;
481 
482 	reg_val = readl(mdata->base + SPI_CFG1_REG);
483 	if (mdata->dev_comp->ipm_design)
484 		reg_val &= ~SPI_CFG1_IPM_PACKET_LENGTH_MASK;
485 	else
486 		reg_val &= ~SPI_CFG1_PACKET_LENGTH_MASK;
487 	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
488 	reg_val &= ~SPI_CFG1_PACKET_LOOP_MASK;
489 	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
490 	writel(reg_val, mdata->base + SPI_CFG1_REG);
491 }
492 
493 static void mtk_spi_enable_transfer(struct spi_master *master)
494 {
495 	u32 cmd;
496 	struct mtk_spi *mdata = spi_master_get_devdata(master);
497 
498 	cmd = readl(mdata->base + SPI_CMD_REG);
499 	if (mdata->state == MTK_SPI_IDLE)
500 		cmd |= SPI_CMD_ACT;
501 	else
502 		cmd |= SPI_CMD_RESUME;
503 	writel(cmd, mdata->base + SPI_CMD_REG);
504 }
505 
506 static int mtk_spi_get_mult_delta(u32 xfer_len)
507 {
508 	u32 mult_delta;
509 
510 	if (xfer_len > MTK_SPI_PACKET_SIZE)
511 		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
512 	else
513 		mult_delta = 0;
514 
515 	return mult_delta;
516 }
517 
518 static void mtk_spi_update_mdata_len(struct spi_master *master)
519 {
520 	int mult_delta;
521 	struct mtk_spi *mdata = spi_master_get_devdata(master);
522 
523 	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
524 		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
525 			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
526 			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
527 			mdata->rx_sgl_len = mult_delta;
528 			mdata->tx_sgl_len -= mdata->xfer_len;
529 		} else {
530 			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
531 			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
532 			mdata->tx_sgl_len = mult_delta;
533 			mdata->rx_sgl_len -= mdata->xfer_len;
534 		}
535 	} else if (mdata->tx_sgl_len) {
536 		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
537 		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
538 		mdata->tx_sgl_len = mult_delta;
539 	} else if (mdata->rx_sgl_len) {
540 		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
541 		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
542 		mdata->rx_sgl_len = mult_delta;
543 	}
544 }
545 
546 static void mtk_spi_setup_dma_addr(struct spi_master *master,
547 				   struct spi_transfer *xfer)
548 {
549 	struct mtk_spi *mdata = spi_master_get_devdata(master);
550 
551 	if (mdata->tx_sgl) {
552 		writel((u32)(xfer->tx_dma & MTK_SPI_32BITS_MASK),
553 		       mdata->base + SPI_TX_SRC_REG);
554 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
555 		if (mdata->dev_comp->dma_ext)
556 			writel((u32)(xfer->tx_dma >> 32),
557 			       mdata->base + SPI_TX_SRC_REG_64);
558 #endif
559 	}
560 
561 	if (mdata->rx_sgl) {
562 		writel((u32)(xfer->rx_dma & MTK_SPI_32BITS_MASK),
563 		       mdata->base + SPI_RX_DST_REG);
564 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
565 		if (mdata->dev_comp->dma_ext)
566 			writel((u32)(xfer->rx_dma >> 32),
567 			       mdata->base + SPI_RX_DST_REG_64);
568 #endif
569 	}
570 }
571 
572 static int mtk_spi_fifo_transfer(struct spi_master *master,
573 				 struct spi_device *spi,
574 				 struct spi_transfer *xfer)
575 {
576 	int cnt, remainder;
577 	u32 reg_val;
578 	struct mtk_spi *mdata = spi_master_get_devdata(master);
579 
580 	mdata->cur_transfer = xfer;
581 	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
582 	mdata->num_xfered = 0;
583 	mtk_spi_prepare_transfer(master, xfer->speed_hz);
584 	mtk_spi_setup_packet(master);
585 
586 	if (xfer->tx_buf) {
587 		cnt = xfer->len / 4;
588 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
589 		remainder = xfer->len % 4;
590 		if (remainder > 0) {
591 			reg_val = 0;
592 			memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
593 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
594 		}
595 	}
596 
597 	mtk_spi_enable_transfer(master);
598 
599 	return 1;
600 }
601 
602 static int mtk_spi_dma_transfer(struct spi_master *master,
603 				struct spi_device *spi,
604 				struct spi_transfer *xfer)
605 {
606 	int cmd;
607 	struct mtk_spi *mdata = spi_master_get_devdata(master);
608 
609 	mdata->tx_sgl = NULL;
610 	mdata->rx_sgl = NULL;
611 	mdata->tx_sgl_len = 0;
612 	mdata->rx_sgl_len = 0;
613 	mdata->cur_transfer = xfer;
614 	mdata->num_xfered = 0;
615 
616 	mtk_spi_prepare_transfer(master, xfer->speed_hz);
617 
618 	cmd = readl(mdata->base + SPI_CMD_REG);
619 	if (xfer->tx_buf)
620 		cmd |= SPI_CMD_TX_DMA;
621 	if (xfer->rx_buf)
622 		cmd |= SPI_CMD_RX_DMA;
623 	writel(cmd, mdata->base + SPI_CMD_REG);
624 
625 	if (xfer->tx_buf)
626 		mdata->tx_sgl = xfer->tx_sg.sgl;
627 	if (xfer->rx_buf)
628 		mdata->rx_sgl = xfer->rx_sg.sgl;
629 
630 	if (mdata->tx_sgl) {
631 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
632 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
633 	}
634 	if (mdata->rx_sgl) {
635 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
636 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
637 	}
638 
639 	mtk_spi_update_mdata_len(master);
640 	mtk_spi_setup_packet(master);
641 	mtk_spi_setup_dma_addr(master, xfer);
642 	mtk_spi_enable_transfer(master);
643 
644 	return 1;
645 }
646 
647 static int mtk_spi_transfer_one(struct spi_master *master,
648 				struct spi_device *spi,
649 				struct spi_transfer *xfer)
650 {
651 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
652 	u32 reg_val = 0;
653 
654 	/* prepare xfer direction and duplex mode */
655 	if (mdata->dev_comp->ipm_design) {
656 		if (!xfer->tx_buf || !xfer->rx_buf) {
657 			reg_val |= SPI_CFG3_IPM_HALF_DUPLEX_EN;
658 			if (xfer->rx_buf)
659 				reg_val |= SPI_CFG3_IPM_HALF_DUPLEX_DIR;
660 		}
661 		writel(reg_val, mdata->base + SPI_CFG3_IPM_REG);
662 	}
663 
664 	if (master->can_dma(master, spi, xfer))
665 		return mtk_spi_dma_transfer(master, spi, xfer);
666 	else
667 		return mtk_spi_fifo_transfer(master, spi, xfer);
668 }
669 
670 static bool mtk_spi_can_dma(struct spi_master *master,
671 			    struct spi_device *spi,
672 			    struct spi_transfer *xfer)
673 {
674 	/* Buffers for DMA transactions must be 4-byte aligned */
675 	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
676 		(unsigned long)xfer->tx_buf % 4 == 0 &&
677 		(unsigned long)xfer->rx_buf % 4 == 0);
678 }
679 
680 static int mtk_spi_setup(struct spi_device *spi)
681 {
682 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
683 
684 	if (!spi->controller_data)
685 		spi->controller_data = (void *)&mtk_default_chip_info;
686 
687 	if (mdata->dev_comp->need_pad_sel && spi->cs_gpiod)
688 		/* CS de-asserted, gpiolib will handle inversion */
689 		gpiod_direction_output(spi->cs_gpiod, 0);
690 
691 	return 0;
692 }
693 
694 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
695 {
696 	u32 cmd, reg_val, cnt, remainder, len;
697 	struct spi_master *master = dev_id;
698 	struct mtk_spi *mdata = spi_master_get_devdata(master);
699 	struct spi_transfer *trans = mdata->cur_transfer;
700 
701 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
702 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
703 		mdata->state = MTK_SPI_PAUSED;
704 	else
705 		mdata->state = MTK_SPI_IDLE;
706 
707 	if (!master->can_dma(master, NULL, trans)) {
708 		if (trans->rx_buf) {
709 			cnt = mdata->xfer_len / 4;
710 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
711 				     trans->rx_buf + mdata->num_xfered, cnt);
712 			remainder = mdata->xfer_len % 4;
713 			if (remainder > 0) {
714 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
715 				memcpy(trans->rx_buf +
716 					mdata->num_xfered +
717 					(cnt * 4),
718 					&reg_val,
719 					remainder);
720 			}
721 		}
722 
723 		mdata->num_xfered += mdata->xfer_len;
724 		if (mdata->num_xfered == trans->len) {
725 			spi_finalize_current_transfer(master);
726 			return IRQ_HANDLED;
727 		}
728 
729 		len = trans->len - mdata->num_xfered;
730 		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
731 		mtk_spi_setup_packet(master);
732 
733 		cnt = mdata->xfer_len / 4;
734 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
735 				trans->tx_buf + mdata->num_xfered, cnt);
736 
737 		remainder = mdata->xfer_len % 4;
738 		if (remainder > 0) {
739 			reg_val = 0;
740 			memcpy(&reg_val,
741 				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
742 				remainder);
743 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
744 		}
745 
746 		mtk_spi_enable_transfer(master);
747 
748 		return IRQ_HANDLED;
749 	}
750 
751 	if (mdata->tx_sgl)
752 		trans->tx_dma += mdata->xfer_len;
753 	if (mdata->rx_sgl)
754 		trans->rx_dma += mdata->xfer_len;
755 
756 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
757 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
758 		if (mdata->tx_sgl) {
759 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
760 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
761 		}
762 	}
763 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
764 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
765 		if (mdata->rx_sgl) {
766 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
767 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
768 		}
769 	}
770 
771 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
772 		/* spi disable dma */
773 		cmd = readl(mdata->base + SPI_CMD_REG);
774 		cmd &= ~SPI_CMD_TX_DMA;
775 		cmd &= ~SPI_CMD_RX_DMA;
776 		writel(cmd, mdata->base + SPI_CMD_REG);
777 
778 		spi_finalize_current_transfer(master);
779 		return IRQ_HANDLED;
780 	}
781 
782 	mtk_spi_update_mdata_len(master);
783 	mtk_spi_setup_packet(master);
784 	mtk_spi_setup_dma_addr(master, trans);
785 	mtk_spi_enable_transfer(master);
786 
787 	return IRQ_HANDLED;
788 }
789 
790 static int mtk_spi_probe(struct platform_device *pdev)
791 {
792 	struct spi_master *master;
793 	struct mtk_spi *mdata;
794 	const struct of_device_id *of_id;
795 	int i, irq, ret, addr_bits;
796 
797 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
798 	if (!master) {
799 		dev_err(&pdev->dev, "failed to alloc spi master\n");
800 		return -ENOMEM;
801 	}
802 
803 	master->auto_runtime_pm = true;
804 	master->dev.of_node = pdev->dev.of_node;
805 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
806 
807 	master->set_cs = mtk_spi_set_cs;
808 	master->prepare_message = mtk_spi_prepare_message;
809 	master->transfer_one = mtk_spi_transfer_one;
810 	master->can_dma = mtk_spi_can_dma;
811 	master->setup = mtk_spi_setup;
812 	master->set_cs_timing = mtk_spi_set_hw_cs_timing;
813 	master->use_gpio_descriptors = true;
814 
815 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
816 	if (!of_id) {
817 		dev_err(&pdev->dev, "failed to probe of_node\n");
818 		ret = -EINVAL;
819 		goto err_put_master;
820 	}
821 
822 	mdata = spi_master_get_devdata(master);
823 	mdata->dev_comp = of_id->data;
824 
825 	if (mdata->dev_comp->enhance_timing)
826 		master->mode_bits |= SPI_CS_HIGH;
827 
828 	if (mdata->dev_comp->must_tx)
829 		master->flags = SPI_MASTER_MUST_TX;
830 	if (mdata->dev_comp->ipm_design)
831 		master->mode_bits |= SPI_LOOP;
832 
833 	if (mdata->dev_comp->need_pad_sel) {
834 		mdata->pad_num = of_property_count_u32_elems(
835 			pdev->dev.of_node,
836 			"mediatek,pad-select");
837 		if (mdata->pad_num < 0) {
838 			dev_err(&pdev->dev,
839 				"No 'mediatek,pad-select' property\n");
840 			ret = -EINVAL;
841 			goto err_put_master;
842 		}
843 
844 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
845 						    sizeof(u32), GFP_KERNEL);
846 		if (!mdata->pad_sel) {
847 			ret = -ENOMEM;
848 			goto err_put_master;
849 		}
850 
851 		for (i = 0; i < mdata->pad_num; i++) {
852 			of_property_read_u32_index(pdev->dev.of_node,
853 						   "mediatek,pad-select",
854 						   i, &mdata->pad_sel[i]);
855 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
856 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
857 					i, mdata->pad_sel[i]);
858 				ret = -EINVAL;
859 				goto err_put_master;
860 			}
861 		}
862 	}
863 
864 	platform_set_drvdata(pdev, master);
865 	mdata->base = devm_platform_ioremap_resource(pdev, 0);
866 	if (IS_ERR(mdata->base)) {
867 		ret = PTR_ERR(mdata->base);
868 		goto err_put_master;
869 	}
870 
871 	irq = platform_get_irq(pdev, 0);
872 	if (irq < 0) {
873 		ret = irq;
874 		goto err_put_master;
875 	}
876 
877 	if (!pdev->dev.dma_mask)
878 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
879 
880 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
881 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
882 	if (ret) {
883 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
884 		goto err_put_master;
885 	}
886 
887 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
888 	if (IS_ERR(mdata->parent_clk)) {
889 		ret = PTR_ERR(mdata->parent_clk);
890 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
891 		goto err_put_master;
892 	}
893 
894 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
895 	if (IS_ERR(mdata->sel_clk)) {
896 		ret = PTR_ERR(mdata->sel_clk);
897 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
898 		goto err_put_master;
899 	}
900 
901 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
902 	if (IS_ERR(mdata->spi_clk)) {
903 		ret = PTR_ERR(mdata->spi_clk);
904 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
905 		goto err_put_master;
906 	}
907 
908 	ret = clk_prepare_enable(mdata->spi_clk);
909 	if (ret < 0) {
910 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
911 		goto err_put_master;
912 	}
913 
914 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
915 	if (ret < 0) {
916 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
917 		clk_disable_unprepare(mdata->spi_clk);
918 		goto err_put_master;
919 	}
920 
921 	mdata->spi_clk_hz = clk_get_rate(mdata->spi_clk);
922 
923 	if (mdata->dev_comp->no_need_unprepare)
924 		clk_disable(mdata->spi_clk);
925 	else
926 		clk_disable_unprepare(mdata->spi_clk);
927 
928 	pm_runtime_enable(&pdev->dev);
929 
930 	if (mdata->dev_comp->need_pad_sel) {
931 		if (mdata->pad_num != master->num_chipselect) {
932 			dev_err(&pdev->dev,
933 				"pad_num does not match num_chipselect(%d != %d)\n",
934 				mdata->pad_num, master->num_chipselect);
935 			ret = -EINVAL;
936 			goto err_disable_runtime_pm;
937 		}
938 
939 		if (!master->cs_gpiods && master->num_chipselect > 1) {
940 			dev_err(&pdev->dev,
941 				"cs_gpios not specified and num_chipselect > 1\n");
942 			ret = -EINVAL;
943 			goto err_disable_runtime_pm;
944 		}
945 	}
946 
947 	if (mdata->dev_comp->dma_ext)
948 		addr_bits = DMA_ADDR_EXT_BITS;
949 	else
950 		addr_bits = DMA_ADDR_DEF_BITS;
951 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
952 	if (ret)
953 		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
954 			   addr_bits, ret);
955 
956 	ret = devm_spi_register_master(&pdev->dev, master);
957 	if (ret) {
958 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
959 		goto err_disable_runtime_pm;
960 	}
961 
962 	return 0;
963 
964 err_disable_runtime_pm:
965 	pm_runtime_disable(&pdev->dev);
966 err_put_master:
967 	spi_master_put(master);
968 
969 	return ret;
970 }
971 
972 static int mtk_spi_remove(struct platform_device *pdev)
973 {
974 	struct spi_master *master = platform_get_drvdata(pdev);
975 	struct mtk_spi *mdata = spi_master_get_devdata(master);
976 
977 	pm_runtime_disable(&pdev->dev);
978 
979 	mtk_spi_reset(mdata);
980 
981 	if (mdata->dev_comp->no_need_unprepare)
982 		clk_unprepare(mdata->spi_clk);
983 
984 	return 0;
985 }
986 
987 #ifdef CONFIG_PM_SLEEP
988 static int mtk_spi_suspend(struct device *dev)
989 {
990 	int ret;
991 	struct spi_master *master = dev_get_drvdata(dev);
992 	struct mtk_spi *mdata = spi_master_get_devdata(master);
993 
994 	ret = spi_master_suspend(master);
995 	if (ret)
996 		return ret;
997 
998 	if (!pm_runtime_suspended(dev))
999 		clk_disable_unprepare(mdata->spi_clk);
1000 
1001 	return ret;
1002 }
1003 
1004 static int mtk_spi_resume(struct device *dev)
1005 {
1006 	int ret;
1007 	struct spi_master *master = dev_get_drvdata(dev);
1008 	struct mtk_spi *mdata = spi_master_get_devdata(master);
1009 
1010 	if (!pm_runtime_suspended(dev)) {
1011 		ret = clk_prepare_enable(mdata->spi_clk);
1012 		if (ret < 0) {
1013 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
1014 			return ret;
1015 		}
1016 	}
1017 
1018 	ret = spi_master_resume(master);
1019 	if (ret < 0)
1020 		clk_disable_unprepare(mdata->spi_clk);
1021 
1022 	return ret;
1023 }
1024 #endif /* CONFIG_PM_SLEEP */
1025 
1026 #ifdef CONFIG_PM
1027 static int mtk_spi_runtime_suspend(struct device *dev)
1028 {
1029 	struct spi_master *master = dev_get_drvdata(dev);
1030 	struct mtk_spi *mdata = spi_master_get_devdata(master);
1031 
1032 	if (mdata->dev_comp->no_need_unprepare)
1033 		clk_disable(mdata->spi_clk);
1034 	else
1035 		clk_disable_unprepare(mdata->spi_clk);
1036 
1037 	return 0;
1038 }
1039 
1040 static int mtk_spi_runtime_resume(struct device *dev)
1041 {
1042 	struct spi_master *master = dev_get_drvdata(dev);
1043 	struct mtk_spi *mdata = spi_master_get_devdata(master);
1044 	int ret;
1045 
1046 	if (mdata->dev_comp->no_need_unprepare)
1047 		ret = clk_enable(mdata->spi_clk);
1048 	else
1049 		ret = clk_prepare_enable(mdata->spi_clk);
1050 	if (ret < 0) {
1051 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
1052 		return ret;
1053 	}
1054 
1055 	return 0;
1056 }
1057 #endif /* CONFIG_PM */
1058 
1059 static const struct dev_pm_ops mtk_spi_pm = {
1060 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
1061 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
1062 			   mtk_spi_runtime_resume, NULL)
1063 };
1064 
1065 static struct platform_driver mtk_spi_driver = {
1066 	.driver = {
1067 		.name = "mtk-spi",
1068 		.pm	= &mtk_spi_pm,
1069 		.of_match_table = mtk_spi_of_match,
1070 	},
1071 	.probe = mtk_spi_probe,
1072 	.remove = mtk_spi_remove,
1073 };
1074 
1075 module_platform_driver(mtk_spi_driver);
1076 
1077 MODULE_DESCRIPTION("MTK SPI Controller driver");
1078 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
1079 MODULE_LICENSE("GPL v2");
1080 MODULE_ALIAS("platform:mtk-spi");
1081