2 * SuperH MSIOF SPI Master Interface
4 * Copyright (c) 2009 Magnus Damm
5 * Copyright (C) 2014 Glider bvba
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 #include <linux/bitmap.h>
14 #include <linux/clk.h>
15 #include <linux/completion.h>
16 #include <linux/delay.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/dmaengine.h>
19 #include <linux/err.h>
20 #include <linux/gpio.h>
21 #include <linux/interrupt.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
26 #include <linux/of_device.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/sh_dma.h>
31 #include <linux/spi/sh_msiof.h>
32 #include <linux/spi/spi.h>
34 #include <asm/unaligned.h>
37 struct sh_msiof_chipdata {
43 struct sh_msiof_spi_priv {
44 struct spi_master *master;
45 void __iomem *mapbase;
47 struct platform_device *pdev;
48 const struct sh_msiof_chipdata *chipdata;
49 struct sh_msiof_spi_info *info;
50 struct completion done;
55 dma_addr_t tx_dma_addr;
56 dma_addr_t rx_dma_addr;
59 #define TMDR1 0x00 /* Transmit Mode Register 1 */
60 #define TMDR2 0x04 /* Transmit Mode Register 2 */
61 #define TMDR3 0x08 /* Transmit Mode Register 3 */
62 #define RMDR1 0x10 /* Receive Mode Register 1 */
63 #define RMDR2 0x14 /* Receive Mode Register 2 */
64 #define RMDR3 0x18 /* Receive Mode Register 3 */
65 #define TSCR 0x20 /* Transmit Clock Select Register */
66 #define RSCR 0x22 /* Receive Clock Select Register (SH, A1, APE6) */
67 #define CTR 0x28 /* Control Register */
68 #define FCTR 0x30 /* FIFO Control Register */
69 #define STR 0x40 /* Status Register */
70 #define IER 0x44 /* Interrupt Enable Register */
71 #define TDR1 0x48 /* Transmit Control Data Register 1 (SH, A1) */
72 #define TDR2 0x4c /* Transmit Control Data Register 2 (SH, A1) */
73 #define TFDR 0x50 /* Transmit FIFO Data Register */
74 #define RDR1 0x58 /* Receive Control Data Register 1 (SH, A1) */
75 #define RDR2 0x5c /* Receive Control Data Register 2 (SH, A1) */
76 #define RFDR 0x60 /* Receive FIFO Data Register */
79 #define MDR1_TRMD 0x80000000 /* Transfer Mode (1 = Master mode) */
80 #define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */
81 #define MDR1_SYNCMD_SPI 0x20000000 /* Level mode/SPI */
82 #define MDR1_SYNCMD_LR 0x30000000 /* L/R mode */
83 #define MDR1_SYNCAC_SHIFT 25 /* Sync Polarity (1 = Active-low) */
84 #define MDR1_BITLSB_SHIFT 24 /* MSB/LSB First (1 = LSB first) */
85 #define MDR1_FLD_MASK 0x000000c0 /* Frame Sync Signal Interval (0-3) */
86 #define MDR1_FLD_SHIFT 2
87 #define MDR1_XXSTP 0x00000001 /* Transmission/Reception Stop on FIFO */
89 #define TMDR1_PCON 0x40000000 /* Transfer Signal Connection */
92 #define MDR2_BITLEN1(i) (((i) - 1) << 24) /* Data Size (8-32 bits) */
93 #define MDR2_WDLEN1(i) (((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
94 #define MDR2_GRPMASK1 0x00000001 /* Group Output Mask 1 (SH, A1) */
96 #define MAX_WDLEN 256U
99 #define SCR_BRPS_MASK 0x1f00 /* Prescaler Setting (1-32) */
100 #define SCR_BRPS(i) (((i) - 1) << 8)
101 #define SCR_BRDV_MASK 0x0007 /* Baud Rate Generator's Division Ratio */
102 #define SCR_BRDV_DIV_2 0x0000
103 #define SCR_BRDV_DIV_4 0x0001
104 #define SCR_BRDV_DIV_8 0x0002
105 #define SCR_BRDV_DIV_16 0x0003
106 #define SCR_BRDV_DIV_32 0x0004
107 #define SCR_BRDV_DIV_1 0x0007
110 #define CTR_TSCKIZ_MASK 0xc0000000 /* Transmit Clock I/O Polarity Select */
111 #define CTR_TSCKIZ_SCK 0x80000000 /* Disable SCK when TX disabled */
112 #define CTR_TSCKIZ_POL_SHIFT 30 /* Transmit Clock Polarity */
113 #define CTR_RSCKIZ_MASK 0x30000000 /* Receive Clock Polarity Select */
114 #define CTR_RSCKIZ_SCK 0x20000000 /* Must match CTR_TSCKIZ_SCK */
115 #define CTR_RSCKIZ_POL_SHIFT 28 /* Receive Clock Polarity */
116 #define CTR_TEDG_SHIFT 27 /* Transmit Timing (1 = falling edge) */
117 #define CTR_REDG_SHIFT 26 /* Receive Timing (1 = falling edge) */
118 #define CTR_TXDIZ_MASK 0x00c00000 /* Pin Output When TX is Disabled */
119 #define CTR_TXDIZ_LOW 0x00000000 /* 0 */
120 #define CTR_TXDIZ_HIGH 0x00400000 /* 1 */
121 #define CTR_TXDIZ_HIZ 0x00800000 /* High-impedance */
122 #define CTR_TSCKE 0x00008000 /* Transmit Serial Clock Output Enable */
123 #define CTR_TFSE 0x00004000 /* Transmit Frame Sync Signal Output Enable */
124 #define CTR_TXE 0x00000200 /* Transmit Enable */
125 #define CTR_RXE 0x00000100 /* Receive Enable */
128 #define FCTR_TFWM_MASK 0xe0000000 /* Transmit FIFO Watermark */
129 #define FCTR_TFWM_64 0x00000000 /* Transfer Request when 64 empty stages */
130 #define FCTR_TFWM_32 0x20000000 /* Transfer Request when 32 empty stages */
131 #define FCTR_TFWM_24 0x40000000 /* Transfer Request when 24 empty stages */
132 #define FCTR_TFWM_16 0x60000000 /* Transfer Request when 16 empty stages */
133 #define FCTR_TFWM_12 0x80000000 /* Transfer Request when 12 empty stages */
134 #define FCTR_TFWM_8 0xa0000000 /* Transfer Request when 8 empty stages */
135 #define FCTR_TFWM_4 0xc0000000 /* Transfer Request when 4 empty stages */
136 #define FCTR_TFWM_1 0xe0000000 /* Transfer Request when 1 empty stage */
137 #define FCTR_TFUA_MASK 0x07f00000 /* Transmit FIFO Usable Area */
138 #define FCTR_TFUA_SHIFT 20
139 #define FCTR_TFUA(i) ((i) << FCTR_TFUA_SHIFT)
140 #define FCTR_RFWM_MASK 0x0000e000 /* Receive FIFO Watermark */
141 #define FCTR_RFWM_1 0x00000000 /* Transfer Request when 1 valid stages */
142 #define FCTR_RFWM_4 0x00002000 /* Transfer Request when 4 valid stages */
143 #define FCTR_RFWM_8 0x00004000 /* Transfer Request when 8 valid stages */
144 #define FCTR_RFWM_16 0x00006000 /* Transfer Request when 16 valid stages */
145 #define FCTR_RFWM_32 0x00008000 /* Transfer Request when 32 valid stages */
146 #define FCTR_RFWM_64 0x0000a000 /* Transfer Request when 64 valid stages */
147 #define FCTR_RFWM_128 0x0000c000 /* Transfer Request when 128 valid stages */
148 #define FCTR_RFWM_256 0x0000e000 /* Transfer Request when 256 valid stages */
149 #define FCTR_RFUA_MASK 0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */
150 #define FCTR_RFUA_SHIFT 4
151 #define FCTR_RFUA(i) ((i) << FCTR_RFUA_SHIFT)
154 #define STR_TFEMP 0x20000000 /* Transmit FIFO Empty */
155 #define STR_TDREQ 0x10000000 /* Transmit Data Transfer Request */
156 #define STR_TEOF 0x00800000 /* Frame Transmission End */
157 #define STR_TFSERR 0x00200000 /* Transmit Frame Synchronization Error */
158 #define STR_TFOVF 0x00100000 /* Transmit FIFO Overflow */
159 #define STR_TFUDF 0x00080000 /* Transmit FIFO Underflow */
160 #define STR_RFFUL 0x00002000 /* Receive FIFO Full */
161 #define STR_RDREQ 0x00001000 /* Receive Data Transfer Request */
162 #define STR_REOF 0x00000080 /* Frame Reception End */
163 #define STR_RFSERR 0x00000020 /* Receive Frame Synchronization Error */
164 #define STR_RFUDF 0x00000010 /* Receive FIFO Underflow */
165 #define STR_RFOVF 0x00000008 /* Receive FIFO Overflow */
168 #define IER_TDMAE 0x80000000 /* Transmit Data DMA Transfer Req. Enable */
169 #define IER_TFEMPE 0x20000000 /* Transmit FIFO Empty Enable */
170 #define IER_TDREQE 0x10000000 /* Transmit Data Transfer Request Enable */
171 #define IER_TEOFE 0x00800000 /* Frame Transmission End Enable */
172 #define IER_TFSERRE 0x00200000 /* Transmit Frame Sync Error Enable */
173 #define IER_TFOVFE 0x00100000 /* Transmit FIFO Overflow Enable */
174 #define IER_TFUDFE 0x00080000 /* Transmit FIFO Underflow Enable */
175 #define IER_RDMAE 0x00008000 /* Receive Data DMA Transfer Req. Enable */
176 #define IER_RFFULE 0x00002000 /* Receive FIFO Full Enable */
177 #define IER_RDREQE 0x00001000 /* Receive Data Transfer Request Enable */
178 #define IER_REOFE 0x00000080 /* Frame Reception End Enable */
179 #define IER_RFSERRE 0x00000020 /* Receive Frame Sync Error Enable */
180 #define IER_RFUDFE 0x00000010 /* Receive FIFO Underflow Enable */
181 #define IER_RFOVFE 0x00000008 /* Receive FIFO Overflow Enable */
184 static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
189 return ioread16(p->mapbase + reg_offs);
191 return ioread32(p->mapbase + reg_offs);
195 static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
201 iowrite16(value, p->mapbase + reg_offs);
204 iowrite32(value, p->mapbase + reg_offs);
209 static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
212 u32 mask = clr | set;
216 data = sh_msiof_read(p, CTR);
219 sh_msiof_write(p, CTR, data);
221 for (k = 100; k > 0; k--) {
222 if ((sh_msiof_read(p, CTR) & mask) == set)
228 return k > 0 ? 0 : -ETIMEDOUT;
231 static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
233 struct sh_msiof_spi_priv *p = data;
235 /* just disable the interrupt and wake up */
236 sh_msiof_write(p, IER, 0);
245 } const sh_msiof_spi_clk_table[] = {
246 { 1, SCR_BRPS( 1) | SCR_BRDV_DIV_1 },
247 { 2, SCR_BRPS( 1) | SCR_BRDV_DIV_2 },
248 { 4, SCR_BRPS( 1) | SCR_BRDV_DIV_4 },
249 { 8, SCR_BRPS( 1) | SCR_BRDV_DIV_8 },
250 { 16, SCR_BRPS( 1) | SCR_BRDV_DIV_16 },
251 { 32, SCR_BRPS( 1) | SCR_BRDV_DIV_32 },
252 { 64, SCR_BRPS(32) | SCR_BRDV_DIV_2 },
253 { 128, SCR_BRPS(32) | SCR_BRDV_DIV_4 },
254 { 256, SCR_BRPS(32) | SCR_BRDV_DIV_8 },
255 { 512, SCR_BRPS(32) | SCR_BRDV_DIV_16 },
256 { 1024, SCR_BRPS(32) | SCR_BRDV_DIV_32 },
259 static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
260 unsigned long parent_rate, u32 spi_hz)
262 unsigned long div = 1024;
265 if (!WARN_ON(!spi_hz || !parent_rate))
266 div = DIV_ROUND_UP(parent_rate, spi_hz);
268 /* TODO: make more fine grained */
270 for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_clk_table); k++) {
271 if (sh_msiof_spi_clk_table[k].div >= div)
275 k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_clk_table) - 1);
277 sh_msiof_write(p, TSCR, sh_msiof_spi_clk_table[k].scr);
278 if (!(p->chipdata->master_flags & SPI_MASTER_MUST_TX))
279 sh_msiof_write(p, RSCR, sh_msiof_spi_clk_table[k].scr);
282 static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
284 u32 tx_hi_z, u32 lsb_first, u32 cs_high)
290 * CPOL CPHA TSCKIZ RSCKIZ TEDG REDG
296 tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP;
297 tmp |= !cs_high << MDR1_SYNCAC_SHIFT;
298 tmp |= lsb_first << MDR1_BITLSB_SHIFT;
299 sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON);
300 if (p->chipdata->master_flags & SPI_MASTER_MUST_TX) {
301 /* These bits are reserved if RX needs TX */
304 sh_msiof_write(p, RMDR1, tmp);
307 tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT;
308 tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT;
312 tmp |= edge << CTR_TEDG_SHIFT;
313 tmp |= edge << CTR_REDG_SHIFT;
314 tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW;
315 sh_msiof_write(p, CTR, tmp);
318 static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
319 const void *tx_buf, void *rx_buf,
322 u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words);
324 if (tx_buf || (p->chipdata->master_flags & SPI_MASTER_MUST_TX))
325 sh_msiof_write(p, TMDR2, dr2);
327 sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1);
330 sh_msiof_write(p, RMDR2, dr2);
333 static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
335 sh_msiof_write(p, STR, sh_msiof_read(p, STR));
338 static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
339 const void *tx_buf, int words, int fs)
341 const u8 *buf_8 = tx_buf;
344 for (k = 0; k < words; k++)
345 sh_msiof_write(p, TFDR, buf_8[k] << fs);
348 static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
349 const void *tx_buf, int words, int fs)
351 const u16 *buf_16 = tx_buf;
354 for (k = 0; k < words; k++)
355 sh_msiof_write(p, TFDR, buf_16[k] << fs);
358 static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
359 const void *tx_buf, int words, int fs)
361 const u16 *buf_16 = tx_buf;
364 for (k = 0; k < words; k++)
365 sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
368 static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
369 const void *tx_buf, int words, int fs)
371 const u32 *buf_32 = tx_buf;
374 for (k = 0; k < words; k++)
375 sh_msiof_write(p, TFDR, buf_32[k] << fs);
378 static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
379 const void *tx_buf, int words, int fs)
381 const u32 *buf_32 = tx_buf;
384 for (k = 0; k < words; k++)
385 sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
388 static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
389 const void *tx_buf, int words, int fs)
391 const u32 *buf_32 = tx_buf;
394 for (k = 0; k < words; k++)
395 sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
398 static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
399 const void *tx_buf, int words, int fs)
401 const u32 *buf_32 = tx_buf;
404 for (k = 0; k < words; k++)
405 sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
408 static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
409 void *rx_buf, int words, int fs)
414 for (k = 0; k < words; k++)
415 buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
418 static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
419 void *rx_buf, int words, int fs)
421 u16 *buf_16 = rx_buf;
424 for (k = 0; k < words; k++)
425 buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
428 static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
429 void *rx_buf, int words, int fs)
431 u16 *buf_16 = rx_buf;
434 for (k = 0; k < words; k++)
435 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
438 static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
439 void *rx_buf, int words, int fs)
441 u32 *buf_32 = rx_buf;
444 for (k = 0; k < words; k++)
445 buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
448 static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
449 void *rx_buf, int words, int fs)
451 u32 *buf_32 = rx_buf;
454 for (k = 0; k < words; k++)
455 put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
458 static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
459 void *rx_buf, int words, int fs)
461 u32 *buf_32 = rx_buf;
464 for (k = 0; k < words; k++)
465 buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
468 static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
469 void *rx_buf, int words, int fs)
471 u32 *buf_32 = rx_buf;
474 for (k = 0; k < words; k++)
475 put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
478 static int sh_msiof_spi_setup(struct spi_device *spi)
480 struct device_node *np = spi->master->dev.of_node;
481 struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
483 pm_runtime_get_sync(&p->pdev->dev);
487 * Use spi->controller_data for CS (same strategy as spi_gpio),
488 * if any. otherwise let HW control CS
490 spi->cs_gpio = (uintptr_t)spi->controller_data;
493 /* Configure pins before deasserting CS */
494 sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
495 !!(spi->mode & SPI_CPHA),
496 !!(spi->mode & SPI_3WIRE),
497 !!(spi->mode & SPI_LSB_FIRST),
498 !!(spi->mode & SPI_CS_HIGH));
500 if (spi->cs_gpio >= 0)
501 gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
504 pm_runtime_put_sync(&p->pdev->dev);
509 static int sh_msiof_prepare_message(struct spi_master *master,
510 struct spi_message *msg)
512 struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
513 const struct spi_device *spi = msg->spi;
515 /* Configure pins before asserting CS */
516 sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
517 !!(spi->mode & SPI_CPHA),
518 !!(spi->mode & SPI_3WIRE),
519 !!(spi->mode & SPI_LSB_FIRST),
520 !!(spi->mode & SPI_CS_HIGH));
524 static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
528 /* setup clock and rx/tx signals */
529 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
531 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
533 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
535 /* start by setting frame bit */
537 ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
542 static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
546 /* shut down frame, rx/tx and clock signals */
547 ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
549 ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
551 ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
553 ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
558 static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
559 void (*tx_fifo)(struct sh_msiof_spi_priv *,
560 const void *, int, int),
561 void (*rx_fifo)(struct sh_msiof_spi_priv *,
563 const void *tx_buf, void *rx_buf,
569 /* limit maximum word transfer to rx/tx fifo size */
571 words = min_t(int, words, p->tx_fifo_size);
573 words = min_t(int, words, p->rx_fifo_size);
575 /* the fifo contents need shifting */
576 fifo_shift = 32 - bits;
578 /* default FIFO watermarks for PIO */
579 sh_msiof_write(p, FCTR, 0);
581 /* setup msiof transfer mode registers */
582 sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
583 sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE);
587 tx_fifo(p, tx_buf, words, fifo_shift);
589 reinit_completion(&p->done);
591 ret = sh_msiof_spi_start(p, rx_buf);
593 dev_err(&p->pdev->dev, "failed to start hardware\n");
597 /* wait for tx fifo to be emptied / rx fifo to be filled */
598 ret = wait_for_completion_timeout(&p->done, HZ);
600 dev_err(&p->pdev->dev, "PIO timeout\n");
607 rx_fifo(p, rx_buf, words, fifo_shift);
609 /* clear status bits */
610 sh_msiof_reset_str(p);
612 ret = sh_msiof_spi_stop(p, rx_buf);
614 dev_err(&p->pdev->dev, "failed to shut down hardware\n");
621 sh_msiof_reset_str(p);
622 sh_msiof_spi_stop(p, rx_buf);
624 sh_msiof_write(p, IER, 0);
628 static void sh_msiof_dma_complete(void *arg)
630 struct sh_msiof_spi_priv *p = arg;
632 sh_msiof_write(p, IER, 0);
636 static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
637 void *rx, unsigned int len)
640 struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
644 /* First prepare and submit the DMA request(s), as this may fail */
646 ier_bits |= IER_RDREQE | IER_RDMAE;
647 desc_rx = dmaengine_prep_slave_single(p->master->dma_rx,
648 p->rx_dma_addr, len, DMA_FROM_DEVICE,
649 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
653 desc_rx->callback = sh_msiof_dma_complete;
654 desc_rx->callback_param = p;
655 cookie = dmaengine_submit(desc_rx);
656 if (dma_submit_error(cookie))
661 ier_bits |= IER_TDREQE | IER_TDMAE;
662 dma_sync_single_for_device(p->master->dma_tx->device->dev,
663 p->tx_dma_addr, len, DMA_TO_DEVICE);
664 desc_tx = dmaengine_prep_slave_single(p->master->dma_tx,
665 p->tx_dma_addr, len, DMA_TO_DEVICE,
666 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
674 desc_tx->callback = NULL;
676 desc_tx->callback = sh_msiof_dma_complete;
677 desc_tx->callback_param = p;
679 cookie = dmaengine_submit(desc_tx);
680 if (dma_submit_error(cookie)) {
686 /* 1 stage FIFO watermarks for DMA */
687 sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
689 /* setup msiof transfer mode registers (32-bit words) */
690 sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
692 sh_msiof_write(p, IER, ier_bits);
694 reinit_completion(&p->done);
698 dma_async_issue_pending(p->master->dma_rx);
700 dma_async_issue_pending(p->master->dma_tx);
702 ret = sh_msiof_spi_start(p, rx);
704 dev_err(&p->pdev->dev, "failed to start hardware\n");
708 /* wait for tx fifo to be emptied / rx fifo to be filled */
709 ret = wait_for_completion_timeout(&p->done, HZ);
711 dev_err(&p->pdev->dev, "DMA timeout\n");
716 /* clear status bits */
717 sh_msiof_reset_str(p);
719 ret = sh_msiof_spi_stop(p, rx);
721 dev_err(&p->pdev->dev, "failed to shut down hardware\n");
726 dma_sync_single_for_cpu(p->master->dma_rx->device->dev,
733 sh_msiof_reset_str(p);
734 sh_msiof_spi_stop(p, rx);
737 dmaengine_terminate_all(p->master->dma_tx);
740 dmaengine_terminate_all(p->master->dma_rx);
741 sh_msiof_write(p, IER, 0);
745 static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words)
747 /* src or dst can be unaligned, but not both */
748 if ((unsigned long)src & 3) {
750 *dst++ = swab32(get_unaligned(src));
753 } else if ((unsigned long)dst & 3) {
755 put_unaligned(swab32(*src++), dst);
760 *dst++ = swab32(*src++);
764 static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words)
766 /* src or dst can be unaligned, but not both */
767 if ((unsigned long)src & 3) {
769 *dst++ = swahw32(get_unaligned(src));
772 } else if ((unsigned long)dst & 3) {
774 put_unaligned(swahw32(*src++), dst);
779 *dst++ = swahw32(*src++);
783 static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
785 memcpy(dst, src, words * 4);
788 static int sh_msiof_transfer_one(struct spi_master *master,
789 struct spi_device *spi,
790 struct spi_transfer *t)
792 struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
793 void (*copy32)(u32 *, const u32 *, unsigned int);
794 void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
795 void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
796 const void *tx_buf = t->tx_buf;
797 void *rx_buf = t->rx_buf;
798 unsigned int len = t->len;
799 unsigned int bits = t->bits_per_word;
800 unsigned int bytes_per_word;
806 /* setup clocks (clock already enabled in chipselect()) */
807 sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
809 while (master->dma_tx && len > 15) {
811 * DMA supports 32-bit words only, hence pack 8-bit and 16-bit
812 * words, with byte resp. word swapping.
814 unsigned int l = min(len, MAX_WDLEN * 4);
819 copy32 = copy_bswap32;
820 } else if (bits <= 16) {
823 copy32 = copy_wswap32;
825 copy32 = copy_plain32;
829 copy32(p->tx_dma_page, tx_buf, l / 4);
831 ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
832 if (ret == -EAGAIN) {
833 pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
834 dev_driver_string(&p->pdev->dev),
835 dev_name(&p->pdev->dev));
842 copy32(rx_buf, p->rx_dma_page, l / 4);
853 if (bits <= 8 && len > 15 && !(len & 3)) {
860 /* setup bytes per word and fifo read/write functions */
863 tx_fifo = sh_msiof_spi_write_fifo_8;
864 rx_fifo = sh_msiof_spi_read_fifo_8;
865 } else if (bits <= 16) {
867 if ((unsigned long)tx_buf & 0x01)
868 tx_fifo = sh_msiof_spi_write_fifo_16u;
870 tx_fifo = sh_msiof_spi_write_fifo_16;
872 if ((unsigned long)rx_buf & 0x01)
873 rx_fifo = sh_msiof_spi_read_fifo_16u;
875 rx_fifo = sh_msiof_spi_read_fifo_16;
878 if ((unsigned long)tx_buf & 0x03)
879 tx_fifo = sh_msiof_spi_write_fifo_s32u;
881 tx_fifo = sh_msiof_spi_write_fifo_s32;
883 if ((unsigned long)rx_buf & 0x03)
884 rx_fifo = sh_msiof_spi_read_fifo_s32u;
886 rx_fifo = sh_msiof_spi_read_fifo_s32;
889 if ((unsigned long)tx_buf & 0x03)
890 tx_fifo = sh_msiof_spi_write_fifo_32u;
892 tx_fifo = sh_msiof_spi_write_fifo_32;
894 if ((unsigned long)rx_buf & 0x03)
895 rx_fifo = sh_msiof_spi_read_fifo_32u;
897 rx_fifo = sh_msiof_spi_read_fifo_32;
900 /* transfer in fifo sized chunks */
901 words = len / bytes_per_word;
904 n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
910 tx_buf += n * bytes_per_word;
912 rx_buf += n * bytes_per_word;
919 static const struct sh_msiof_chipdata sh_data = {
925 static const struct sh_msiof_chipdata r8a779x_data = {
928 .master_flags = SPI_MASTER_MUST_TX,
931 static const struct of_device_id sh_msiof_match[] = {
932 { .compatible = "renesas,sh-msiof", .data = &sh_data },
933 { .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
934 { .compatible = "renesas,msiof-r8a7790", .data = &r8a779x_data },
935 { .compatible = "renesas,msiof-r8a7791", .data = &r8a779x_data },
936 { .compatible = "renesas,msiof-r8a7792", .data = &r8a779x_data },
937 { .compatible = "renesas,msiof-r8a7793", .data = &r8a779x_data },
938 { .compatible = "renesas,msiof-r8a7794", .data = &r8a779x_data },
941 MODULE_DEVICE_TABLE(of, sh_msiof_match);
944 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
946 struct sh_msiof_spi_info *info;
947 struct device_node *np = dev->of_node;
950 info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
954 /* Parse the MSIOF properties */
955 of_property_read_u32(np, "num-cs", &num_cs);
956 of_property_read_u32(np, "renesas,tx-fifo-size",
957 &info->tx_fifo_override);
958 of_property_read_u32(np, "renesas,rx-fifo-size",
959 &info->rx_fifo_override);
961 info->num_chipselect = num_cs;
966 static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
972 static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
973 enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
976 struct dma_chan *chan;
977 struct dma_slave_config cfg;
981 dma_cap_set(DMA_SLAVE, mask);
983 chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
984 (void *)(unsigned long)id, dev,
985 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
987 dev_warn(dev, "dma_request_slave_channel_compat failed\n");
991 memset(&cfg, 0, sizeof(cfg));
994 if (dir == DMA_MEM_TO_DEV) {
995 cfg.dst_addr = port_addr;
996 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
998 cfg.src_addr = port_addr;
999 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1002 ret = dmaengine_slave_config(chan, &cfg);
1004 dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1005 dma_release_channel(chan);
1012 static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1014 struct platform_device *pdev = p->pdev;
1015 struct device *dev = &pdev->dev;
1016 const struct sh_msiof_spi_info *info = dev_get_platdata(dev);
1017 unsigned int dma_tx_id, dma_rx_id;
1018 const struct resource *res;
1019 struct spi_master *master;
1020 struct device *tx_dev, *rx_dev;
1023 /* In the OF case we will get the slave IDs from the DT */
1026 } else if (info && info->dma_tx_id && info->dma_rx_id) {
1027 dma_tx_id = info->dma_tx_id;
1028 dma_rx_id = info->dma_rx_id;
1030 /* The driver assumes no error */
1034 /* The DMA engine uses the second register set, if present */
1035 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1037 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1040 master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1043 if (!master->dma_tx)
1046 master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1049 if (!master->dma_rx)
1052 p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1053 if (!p->tx_dma_page)
1056 p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1057 if (!p->rx_dma_page)
1060 tx_dev = master->dma_tx->device->dev;
1061 p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1063 if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1066 rx_dev = master->dma_rx->device->dev;
1067 p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1069 if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1072 dev_info(dev, "DMA available");
1076 dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1078 free_page((unsigned long)p->rx_dma_page);
1080 free_page((unsigned long)p->tx_dma_page);
1082 dma_release_channel(master->dma_rx);
1084 dma_release_channel(master->dma_tx);
1085 master->dma_tx = NULL;
1089 static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1091 struct spi_master *master = p->master;
1094 if (!master->dma_tx)
1097 dev = &p->pdev->dev;
1098 dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr,
1099 PAGE_SIZE, DMA_FROM_DEVICE);
1100 dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr,
1101 PAGE_SIZE, DMA_TO_DEVICE);
1102 free_page((unsigned long)p->rx_dma_page);
1103 free_page((unsigned long)p->tx_dma_page);
1104 dma_release_channel(master->dma_rx);
1105 dma_release_channel(master->dma_tx);
1108 static int sh_msiof_spi_probe(struct platform_device *pdev)
1111 struct spi_master *master;
1112 const struct of_device_id *of_id;
1113 struct sh_msiof_spi_priv *p;
1117 master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
1118 if (master == NULL) {
1119 dev_err(&pdev->dev, "failed to allocate spi master\n");
1123 p = spi_master_get_devdata(master);
1125 platform_set_drvdata(pdev, p);
1128 of_id = of_match_device(sh_msiof_match, &pdev->dev);
1130 p->chipdata = of_id->data;
1131 p->info = sh_msiof_spi_parse_dt(&pdev->dev);
1133 p->chipdata = (const void *)pdev->id_entry->driver_data;
1134 p->info = dev_get_platdata(&pdev->dev);
1138 dev_err(&pdev->dev, "failed to obtain device info\n");
1143 init_completion(&p->done);
1145 p->clk = devm_clk_get(&pdev->dev, NULL);
1146 if (IS_ERR(p->clk)) {
1147 dev_err(&pdev->dev, "cannot get clock\n");
1148 ret = PTR_ERR(p->clk);
1152 i = platform_get_irq(pdev, 0);
1154 dev_err(&pdev->dev, "cannot get platform IRQ\n");
1159 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1160 p->mapbase = devm_ioremap_resource(&pdev->dev, r);
1161 if (IS_ERR(p->mapbase)) {
1162 ret = PTR_ERR(p->mapbase);
1166 ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1167 dev_name(&pdev->dev), p);
1169 dev_err(&pdev->dev, "unable to request irq\n");
1174 pm_runtime_enable(&pdev->dev);
1176 /* Platform data may override FIFO sizes */
1177 p->tx_fifo_size = p->chipdata->tx_fifo_size;
1178 p->rx_fifo_size = p->chipdata->rx_fifo_size;
1179 if (p->info->tx_fifo_override)
1180 p->tx_fifo_size = p->info->tx_fifo_override;
1181 if (p->info->rx_fifo_override)
1182 p->rx_fifo_size = p->info->rx_fifo_override;
1184 /* init master code */
1185 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1186 master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1187 master->flags = p->chipdata->master_flags;
1188 master->bus_num = pdev->id;
1189 master->dev.of_node = pdev->dev.of_node;
1190 master->num_chipselect = p->info->num_chipselect;
1191 master->setup = sh_msiof_spi_setup;
1192 master->prepare_message = sh_msiof_prepare_message;
1193 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
1194 master->auto_runtime_pm = true;
1195 master->transfer_one = sh_msiof_transfer_one;
1197 ret = sh_msiof_request_dma(p);
1199 dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1201 ret = devm_spi_register_master(&pdev->dev, master);
1203 dev_err(&pdev->dev, "spi_register_master error.\n");
1210 sh_msiof_release_dma(p);
1211 pm_runtime_disable(&pdev->dev);
1213 spi_master_put(master);
1217 static int sh_msiof_spi_remove(struct platform_device *pdev)
1219 struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
1221 sh_msiof_release_dma(p);
1222 pm_runtime_disable(&pdev->dev);
1226 static struct platform_device_id spi_driver_ids[] = {
1227 { "spi_sh_msiof", (kernel_ulong_t)&sh_data },
1228 { "spi_r8a7790_msiof", (kernel_ulong_t)&r8a779x_data },
1229 { "spi_r8a7791_msiof", (kernel_ulong_t)&r8a779x_data },
1230 { "spi_r8a7792_msiof", (kernel_ulong_t)&r8a779x_data },
1231 { "spi_r8a7793_msiof", (kernel_ulong_t)&r8a779x_data },
1232 { "spi_r8a7794_msiof", (kernel_ulong_t)&r8a779x_data },
1235 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1237 static struct platform_driver sh_msiof_spi_drv = {
1238 .probe = sh_msiof_spi_probe,
1239 .remove = sh_msiof_spi_remove,
1240 .id_table = spi_driver_ids,
1242 .name = "spi_sh_msiof",
1243 .of_match_table = of_match_ptr(sh_msiof_match),
1246 module_platform_driver(sh_msiof_spi_drv);
1248 MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
1249 MODULE_AUTHOR("Magnus Damm");
1250 MODULE_LICENSE("GPL v2");
1251 MODULE_ALIAS("platform:spi_sh_msiof");