2 * Broadcom BCM63xx SPI controller support
4 * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
5 * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
18 #include <linux/kernel.h>
19 #include <linux/clk.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/spi/spi.h>
26 #include <linux/completion.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
30 /* BCM 6338/6348 SPI core */
31 #define SPI_6348_RSET_SIZE 64
32 #define SPI_6348_CMD 0x00 /* 16-bits register */
33 #define SPI_6348_INT_STATUS 0x02
34 #define SPI_6348_INT_MASK_ST 0x03
35 #define SPI_6348_INT_MASK 0x04
36 #define SPI_6348_ST 0x05
37 #define SPI_6348_CLK_CFG 0x06
38 #define SPI_6348_FILL_BYTE 0x07
39 #define SPI_6348_MSG_TAIL 0x09
40 #define SPI_6348_RX_TAIL 0x0b
41 #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
42 #define SPI_6348_MSG_CTL_WIDTH 8
43 #define SPI_6348_MSG_DATA 0x41
44 #define SPI_6348_MSG_DATA_SIZE 0x3f
45 #define SPI_6348_RX_DATA 0x80
46 #define SPI_6348_RX_DATA_SIZE 0x3f
48 /* BCM 3368/6358/6262/6368 SPI core */
49 #define SPI_6358_RSET_SIZE 1804
50 #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
51 #define SPI_6358_MSG_CTL_WIDTH 16
52 #define SPI_6358_MSG_DATA 0x02
53 #define SPI_6358_MSG_DATA_SIZE 0x21e
54 #define SPI_6358_RX_DATA 0x400
55 #define SPI_6358_RX_DATA_SIZE 0x220
56 #define SPI_6358_CMD 0x700 /* 16-bits register */
57 #define SPI_6358_INT_STATUS 0x702
58 #define SPI_6358_INT_MASK_ST 0x703
59 #define SPI_6358_INT_MASK 0x704
60 #define SPI_6358_ST 0x705
61 #define SPI_6358_CLK_CFG 0x706
62 #define SPI_6358_FILL_BYTE 0x707
63 #define SPI_6358_MSG_TAIL 0x709
64 #define SPI_6358_RX_TAIL 0x70B
66 /* Shared SPI definitions */
68 /* Message configuration */
69 #define SPI_FD_RW 0x00
72 #define SPI_BYTE_CNT_SHIFT 0
73 #define SPI_6348_MSG_TYPE_SHIFT 6
74 #define SPI_6358_MSG_TYPE_SHIFT 14
77 #define SPI_CMD_NOOP 0x00
78 #define SPI_CMD_SOFT_RESET 0x01
79 #define SPI_CMD_HARD_RESET 0x02
80 #define SPI_CMD_START_IMMEDIATE 0x03
81 #define SPI_CMD_COMMAND_SHIFT 0
82 #define SPI_CMD_COMMAND_MASK 0x000f
83 #define SPI_CMD_DEVICE_ID_SHIFT 4
84 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
85 #define SPI_CMD_ONE_BYTE_SHIFT 11
86 #define SPI_CMD_ONE_WIRE_SHIFT 12
87 #define SPI_DEV_ID_0 0
88 #define SPI_DEV_ID_1 1
89 #define SPI_DEV_ID_2 2
90 #define SPI_DEV_ID_3 3
93 #define SPI_INTR_CMD_DONE 0x01
94 #define SPI_INTR_RX_OVERFLOW 0x02
95 #define SPI_INTR_TX_UNDERFLOW 0x04
96 #define SPI_INTR_TX_OVERFLOW 0x08
97 #define SPI_INTR_RX_UNDERFLOW 0x10
98 #define SPI_INTR_CLEAR_ALL 0x1f
101 #define SPI_RX_EMPTY 0x02
102 #define SPI_CMD_BUSY 0x04
103 #define SPI_SERIAL_BUSY 0x08
105 /* Clock configuration */
106 #define SPI_CLK_20MHZ 0x00
107 #define SPI_CLK_0_391MHZ 0x01
108 #define SPI_CLK_0_781MHZ 0x02 /* default */
109 #define SPI_CLK_1_563MHZ 0x03
110 #define SPI_CLK_3_125MHZ 0x04
111 #define SPI_CLK_6_250MHZ 0x05
112 #define SPI_CLK_12_50MHZ 0x06
113 #define SPI_CLK_MASK 0x07
114 #define SPI_SSOFFTIME_MASK 0x38
115 #define SPI_SSOFFTIME_SHIFT 3
116 #define SPI_BYTE_SWAP 0x80
118 enum bcm63xx_regs_spi
{
136 #define BCM63XX_SPI_MAX_PREPEND 15
138 #define BCM63XX_SPI_MAX_CS 8
139 #define BCM63XX_SPI_BUS_NUM 0
142 struct completion done
;
148 const unsigned long *reg_offsets
;
150 unsigned int msg_type_shift
;
151 unsigned int msg_ctl_width
;
155 const u8 __iomem
*rx_io
;
158 struct platform_device
*pdev
;
161 static inline u8
bcm_spi_readb(struct bcm63xx_spi
*bs
,
164 return readb(bs
->regs
+ bs
->reg_offsets
[offset
]);
167 static inline u16
bcm_spi_readw(struct bcm63xx_spi
*bs
,
170 #ifdef CONFIG_CPU_BIG_ENDIAN
171 return ioread16be(bs
->regs
+ bs
->reg_offsets
[offset
]);
173 return readw(bs
->regs
+ bs
->reg_offsets
[offset
]);
177 static inline void bcm_spi_writeb(struct bcm63xx_spi
*bs
,
178 u8 value
, unsigned int offset
)
180 writeb(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
183 static inline void bcm_spi_writew(struct bcm63xx_spi
*bs
,
184 u16 value
, unsigned int offset
)
186 #ifdef CONFIG_CPU_BIG_ENDIAN
187 iowrite16be(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
189 writew(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
193 static const unsigned bcm63xx_spi_freq_table
[SPI_CLK_MASK
][2] = {
194 { 20000000, SPI_CLK_20MHZ
},
195 { 12500000, SPI_CLK_12_50MHZ
},
196 { 6250000, SPI_CLK_6_250MHZ
},
197 { 3125000, SPI_CLK_3_125MHZ
},
198 { 1563000, SPI_CLK_1_563MHZ
},
199 { 781000, SPI_CLK_0_781MHZ
},
200 { 391000, SPI_CLK_0_391MHZ
}
203 static void bcm63xx_spi_setup_transfer(struct spi_device
*spi
,
204 struct spi_transfer
*t
)
206 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
210 /* Default to lowest clock configuration */
211 clk_cfg
= SPI_CLK_0_391MHZ
;
213 /* Find the closest clock configuration */
214 for (i
= 0; i
< SPI_CLK_MASK
; i
++) {
215 if (t
->speed_hz
>= bcm63xx_spi_freq_table
[i
][0]) {
216 clk_cfg
= bcm63xx_spi_freq_table
[i
][1];
221 /* clear existing clock configuration bits of the register */
222 reg
= bcm_spi_readb(bs
, SPI_CLK_CFG
);
223 reg
&= ~SPI_CLK_MASK
;
226 bcm_spi_writeb(bs
, reg
, SPI_CLK_CFG
);
227 dev_dbg(&spi
->dev
, "Setting clock register to %02x (hz %d)\n",
228 clk_cfg
, t
->speed_hz
);
231 /* the spi->mode bits understood by this driver: */
232 #define MODEBITS (SPI_CPOL | SPI_CPHA)
234 static int bcm63xx_txrx_bufs(struct spi_device
*spi
, struct spi_transfer
*first
,
235 unsigned int num_transfers
)
237 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
240 unsigned int i
, timeout
= 0, prepend_len
= 0, len
= 0;
241 struct spi_transfer
*t
= first
;
245 /* Disable the CMD_DONE interrupt */
246 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
248 dev_dbg(&spi
->dev
, "txrx: tx %p, rx %p, len %d\n",
249 t
->tx_buf
, t
->rx_buf
, t
->len
);
251 if (num_transfers
> 1 && t
->tx_buf
&& t
->len
<= BCM63XX_SPI_MAX_PREPEND
)
252 prepend_len
= t
->len
;
254 /* prepare the buffer */
255 for (i
= 0; i
< num_transfers
; i
++) {
258 memcpy_toio(bs
->tx_io
+ len
, t
->tx_buf
, t
->len
);
260 /* don't prepend more than one tx */
267 /* prepend is half-duplex write only */
274 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
278 reinit_completion(&bs
->done
);
280 /* Fill in the Message control register */
281 msg_ctl
= (len
<< SPI_BYTE_CNT_SHIFT
);
283 if (do_rx
&& do_tx
&& prepend_len
== 0)
284 msg_ctl
|= (SPI_FD_RW
<< bs
->msg_type_shift
);
286 msg_ctl
|= (SPI_HD_R
<< bs
->msg_type_shift
);
288 msg_ctl
|= (SPI_HD_W
<< bs
->msg_type_shift
);
290 switch (bs
->msg_ctl_width
) {
292 bcm_spi_writeb(bs
, msg_ctl
, SPI_MSG_CTL
);
295 bcm_spi_writew(bs
, msg_ctl
, SPI_MSG_CTL
);
299 /* Issue the transfer */
300 cmd
= SPI_CMD_START_IMMEDIATE
;
301 cmd
|= (prepend_len
<< SPI_CMD_PREPEND_BYTE_CNT_SHIFT
);
302 cmd
|= (spi
->chip_select
<< SPI_CMD_DEVICE_ID_SHIFT
);
303 bcm_spi_writew(bs
, cmd
, SPI_CMD
);
305 /* Enable the CMD_DONE interrupt */
306 bcm_spi_writeb(bs
, SPI_INTR_CMD_DONE
, SPI_INT_MASK
);
308 timeout
= wait_for_completion_timeout(&bs
->done
, HZ
);
317 /* Read out all the data */
318 for (i
= 0; i
< num_transfers
; i
++) {
320 memcpy_fromio(t
->rx_buf
, bs
->rx_io
+ len
, t
->len
);
322 if (t
!= first
|| prepend_len
== 0)
325 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
332 static int bcm63xx_spi_transfer_one(struct spi_master
*master
,
333 struct spi_message
*m
)
335 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
336 struct spi_transfer
*t
, *first
= NULL
;
337 struct spi_device
*spi
= m
->spi
;
339 unsigned int n_transfers
= 0, total_len
= 0;
340 bool can_use_prepend
= false;
343 * This SPI controller does not support keeping CS active after a
345 * Work around this by merging as many transfers we can into one big
346 * full-duplex transfers.
348 list_for_each_entry(t
, &m
->transfers
, transfer_list
) {
355 if (n_transfers
== 2 && !first
->rx_buf
&& !t
->tx_buf
&&
356 first
->len
<= BCM63XX_SPI_MAX_PREPEND
)
357 can_use_prepend
= true;
358 else if (can_use_prepend
&& t
->tx_buf
)
359 can_use_prepend
= false;
361 /* we can only transfer one fifo worth of data */
362 if ((can_use_prepend
&&
363 total_len
> (bs
->fifo_size
+ BCM63XX_SPI_MAX_PREPEND
)) ||
364 (!can_use_prepend
&& total_len
> bs
->fifo_size
)) {
365 dev_err(&spi
->dev
, "unable to do transfers larger than FIFO size (%i > %i)\n",
366 total_len
, bs
->fifo_size
);
371 /* all combined transfers have to have the same speed */
372 if (t
->speed_hz
!= first
->speed_hz
) {
373 dev_err(&spi
->dev
, "unable to change speed between transfers\n");
378 /* CS will be deasserted directly after transfer */
379 if (t
->delay_usecs
) {
380 dev_err(&spi
->dev
, "unable to keep CS asserted after transfer\n");
386 list_is_last(&t
->transfer_list
, &m
->transfers
)) {
387 /* configure adapter for a new transfer */
388 bcm63xx_spi_setup_transfer(spi
, first
);
391 status
= bcm63xx_txrx_bufs(spi
, first
, n_transfers
);
395 m
->actual_length
+= total_len
;
400 can_use_prepend
= false;
405 spi_finalize_current_message(master
);
410 /* This driver supports single master mode only. Hence
411 * CMD_DONE is the only interrupt we care about
413 static irqreturn_t
bcm63xx_spi_interrupt(int irq
, void *dev_id
)
415 struct spi_master
*master
= (struct spi_master
*)dev_id
;
416 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
419 /* Read interupts and clear them immediately */
420 intr
= bcm_spi_readb(bs
, SPI_INT_STATUS
);
421 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
422 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
424 /* A transfer completed */
425 if (intr
& SPI_INTR_CMD_DONE
)
431 static const unsigned long bcm6348_spi_reg_offsets
[] = {
432 [SPI_CMD
] = SPI_6348_CMD
,
433 [SPI_INT_STATUS
] = SPI_6348_INT_STATUS
,
434 [SPI_INT_MASK_ST
] = SPI_6348_INT_MASK_ST
,
435 [SPI_INT_MASK
] = SPI_6348_INT_MASK
,
436 [SPI_ST
] = SPI_6348_ST
,
437 [SPI_CLK_CFG
] = SPI_6348_CLK_CFG
,
438 [SPI_FILL_BYTE
] = SPI_6348_FILL_BYTE
,
439 [SPI_MSG_TAIL
] = SPI_6348_MSG_TAIL
,
440 [SPI_RX_TAIL
] = SPI_6348_RX_TAIL
,
441 [SPI_MSG_CTL
] = SPI_6348_MSG_CTL
,
442 [SPI_MSG_DATA
] = SPI_6348_MSG_DATA
,
443 [SPI_RX_DATA
] = SPI_6348_RX_DATA
,
444 [SPI_MSG_TYPE_SHIFT
] = SPI_6348_MSG_TYPE_SHIFT
,
445 [SPI_MSG_CTL_WIDTH
] = SPI_6348_MSG_CTL_WIDTH
,
446 [SPI_MSG_DATA_SIZE
] = SPI_6348_MSG_DATA_SIZE
,
449 static const unsigned long bcm6358_spi_reg_offsets
[] = {
450 [SPI_CMD
] = SPI_6358_CMD
,
451 [SPI_INT_STATUS
] = SPI_6358_INT_STATUS
,
452 [SPI_INT_MASK_ST
] = SPI_6358_INT_MASK_ST
,
453 [SPI_INT_MASK
] = SPI_6358_INT_MASK
,
454 [SPI_ST
] = SPI_6358_ST
,
455 [SPI_CLK_CFG
] = SPI_6358_CLK_CFG
,
456 [SPI_FILL_BYTE
] = SPI_6358_FILL_BYTE
,
457 [SPI_MSG_TAIL
] = SPI_6358_MSG_TAIL
,
458 [SPI_RX_TAIL
] = SPI_6358_RX_TAIL
,
459 [SPI_MSG_CTL
] = SPI_6358_MSG_CTL
,
460 [SPI_MSG_DATA
] = SPI_6358_MSG_DATA
,
461 [SPI_RX_DATA
] = SPI_6358_RX_DATA
,
462 [SPI_MSG_TYPE_SHIFT
] = SPI_6358_MSG_TYPE_SHIFT
,
463 [SPI_MSG_CTL_WIDTH
] = SPI_6358_MSG_CTL_WIDTH
,
464 [SPI_MSG_DATA_SIZE
] = SPI_6358_MSG_DATA_SIZE
,
467 static const struct platform_device_id bcm63xx_spi_dev_match
[] = {
469 .name
= "bcm6348-spi",
470 .driver_data
= (unsigned long)bcm6348_spi_reg_offsets
,
473 .name
= "bcm6358-spi",
474 .driver_data
= (unsigned long)bcm6358_spi_reg_offsets
,
480 static int bcm63xx_spi_probe(struct platform_device
*pdev
)
483 const unsigned long *bcm63xx_spireg
;
484 struct device
*dev
= &pdev
->dev
;
486 struct spi_master
*master
;
488 struct bcm63xx_spi
*bs
;
491 if (!pdev
->id_entry
->driver_data
)
494 bcm63xx_spireg
= (const unsigned long *)pdev
->id_entry
->driver_data
;
496 irq
= platform_get_irq(pdev
, 0);
498 dev_err(dev
, "no irq\n");
502 clk
= devm_clk_get(dev
, "spi");
504 dev_err(dev
, "no clock for device\n");
508 master
= spi_alloc_master(dev
, sizeof(*bs
));
510 dev_err(dev
, "out of memory\n");
514 bs
= spi_master_get_devdata(master
);
515 init_completion(&bs
->done
);
517 platform_set_drvdata(pdev
, master
);
520 r
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
521 bs
->regs
= devm_ioremap_resource(&pdev
->dev
, r
);
522 if (IS_ERR(bs
->regs
)) {
523 ret
= PTR_ERR(bs
->regs
);
529 bs
->reg_offsets
= bcm63xx_spireg
;
530 bs
->fifo_size
= bs
->reg_offsets
[SPI_MSG_DATA_SIZE
];
532 ret
= devm_request_irq(&pdev
->dev
, irq
, bcm63xx_spi_interrupt
, 0,
535 dev_err(dev
, "unable to request irq\n");
539 master
->bus_num
= BCM63XX_SPI_BUS_NUM
;
540 master
->num_chipselect
= BCM63XX_SPI_MAX_CS
;
541 master
->transfer_one_message
= bcm63xx_spi_transfer_one
;
542 master
->mode_bits
= MODEBITS
;
543 master
->bits_per_word_mask
= SPI_BPW_MASK(8);
544 master
->auto_runtime_pm
= true;
545 bs
->msg_type_shift
= bs
->reg_offsets
[SPI_MSG_TYPE_SHIFT
];
546 bs
->msg_ctl_width
= bs
->reg_offsets
[SPI_MSG_CTL_WIDTH
];
547 bs
->tx_io
= (u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_MSG_DATA
]);
548 bs
->rx_io
= (const u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_RX_DATA
]);
550 /* Initialize hardware */
551 ret
= clk_prepare_enable(bs
->clk
);
555 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
557 /* register and we are done */
558 ret
= devm_spi_register_master(dev
, master
);
560 dev_err(dev
, "spi register failed\n");
561 goto out_clk_disable
;
564 dev_info(dev
, "at %pr (irq %d, FIFOs size %d)\n",
565 r
, irq
, bs
->fifo_size
);
570 clk_disable_unprepare(clk
);
572 spi_master_put(master
);
576 static int bcm63xx_spi_remove(struct platform_device
*pdev
)
578 struct spi_master
*master
= platform_get_drvdata(pdev
);
579 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
581 /* reset spi block */
582 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
585 clk_disable_unprepare(bs
->clk
);
590 #ifdef CONFIG_PM_SLEEP
591 static int bcm63xx_spi_suspend(struct device
*dev
)
593 struct spi_master
*master
= dev_get_drvdata(dev
);
594 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
596 spi_master_suspend(master
);
598 clk_disable_unprepare(bs
->clk
);
603 static int bcm63xx_spi_resume(struct device
*dev
)
605 struct spi_master
*master
= dev_get_drvdata(dev
);
606 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
609 ret
= clk_prepare_enable(bs
->clk
);
613 spi_master_resume(master
);
619 static const struct dev_pm_ops bcm63xx_spi_pm_ops
= {
620 SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend
, bcm63xx_spi_resume
)
623 static struct platform_driver bcm63xx_spi_driver
= {
625 .name
= "bcm63xx-spi",
626 .pm
= &bcm63xx_spi_pm_ops
,
628 .id_table
= bcm63xx_spi_dev_match
,
629 .probe
= bcm63xx_spi_probe
,
630 .remove
= bcm63xx_spi_remove
,
633 module_platform_driver(bcm63xx_spi_driver
);
635 MODULE_ALIAS("platform:bcm63xx_spi");
636 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
637 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
638 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
639 MODULE_LICENSE("GPL");