1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Broadcom BCM63xx SPI controller support
5 * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
6 * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
9 #include <linux/kernel.h>
10 #include <linux/clk.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/interrupt.h>
16 #include <linux/spi/spi.h>
17 #include <linux/completion.h>
18 #include <linux/err.h>
19 #include <linux/pm_runtime.h>
22 /* BCM 6338/6348 SPI core */
23 #define SPI_6348_RSET_SIZE 64
24 #define SPI_6348_CMD 0x00 /* 16-bits register */
25 #define SPI_6348_INT_STATUS 0x02
26 #define SPI_6348_INT_MASK_ST 0x03
27 #define SPI_6348_INT_MASK 0x04
28 #define SPI_6348_ST 0x05
29 #define SPI_6348_CLK_CFG 0x06
30 #define SPI_6348_FILL_BYTE 0x07
31 #define SPI_6348_MSG_TAIL 0x09
32 #define SPI_6348_RX_TAIL 0x0b
33 #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
34 #define SPI_6348_MSG_CTL_WIDTH 8
35 #define SPI_6348_MSG_DATA 0x41
36 #define SPI_6348_MSG_DATA_SIZE 0x3f
37 #define SPI_6348_RX_DATA 0x80
38 #define SPI_6348_RX_DATA_SIZE 0x3f
40 /* BCM 3368/6358/6262/6368 SPI core */
41 #define SPI_6358_RSET_SIZE 1804
42 #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
43 #define SPI_6358_MSG_CTL_WIDTH 16
44 #define SPI_6358_MSG_DATA 0x02
45 #define SPI_6358_MSG_DATA_SIZE 0x21e
46 #define SPI_6358_RX_DATA 0x400
47 #define SPI_6358_RX_DATA_SIZE 0x220
48 #define SPI_6358_CMD 0x700 /* 16-bits register */
49 #define SPI_6358_INT_STATUS 0x702
50 #define SPI_6358_INT_MASK_ST 0x703
51 #define SPI_6358_INT_MASK 0x704
52 #define SPI_6358_ST 0x705
53 #define SPI_6358_CLK_CFG 0x706
54 #define SPI_6358_FILL_BYTE 0x707
55 #define SPI_6358_MSG_TAIL 0x709
56 #define SPI_6358_RX_TAIL 0x70B
58 /* Shared SPI definitions */
60 /* Message configuration */
61 #define SPI_FD_RW 0x00
64 #define SPI_BYTE_CNT_SHIFT 0
65 #define SPI_6348_MSG_TYPE_SHIFT 6
66 #define SPI_6358_MSG_TYPE_SHIFT 14
69 #define SPI_CMD_NOOP 0x00
70 #define SPI_CMD_SOFT_RESET 0x01
71 #define SPI_CMD_HARD_RESET 0x02
72 #define SPI_CMD_START_IMMEDIATE 0x03
73 #define SPI_CMD_COMMAND_SHIFT 0
74 #define SPI_CMD_COMMAND_MASK 0x000f
75 #define SPI_CMD_DEVICE_ID_SHIFT 4
76 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
77 #define SPI_CMD_ONE_BYTE_SHIFT 11
78 #define SPI_CMD_ONE_WIRE_SHIFT 12
79 #define SPI_DEV_ID_0 0
80 #define SPI_DEV_ID_1 1
81 #define SPI_DEV_ID_2 2
82 #define SPI_DEV_ID_3 3
85 #define SPI_INTR_CMD_DONE 0x01
86 #define SPI_INTR_RX_OVERFLOW 0x02
87 #define SPI_INTR_TX_UNDERFLOW 0x04
88 #define SPI_INTR_TX_OVERFLOW 0x08
89 #define SPI_INTR_RX_UNDERFLOW 0x10
90 #define SPI_INTR_CLEAR_ALL 0x1f
93 #define SPI_RX_EMPTY 0x02
94 #define SPI_CMD_BUSY 0x04
95 #define SPI_SERIAL_BUSY 0x08
97 /* Clock configuration */
98 #define SPI_CLK_20MHZ 0x00
99 #define SPI_CLK_0_391MHZ 0x01
100 #define SPI_CLK_0_781MHZ 0x02 /* default */
101 #define SPI_CLK_1_563MHZ 0x03
102 #define SPI_CLK_3_125MHZ 0x04
103 #define SPI_CLK_6_250MHZ 0x05
104 #define SPI_CLK_12_50MHZ 0x06
105 #define SPI_CLK_MASK 0x07
106 #define SPI_SSOFFTIME_MASK 0x38
107 #define SPI_SSOFFTIME_SHIFT 3
108 #define SPI_BYTE_SWAP 0x80
110 enum bcm63xx_regs_spi
{
128 #define BCM63XX_SPI_MAX_PREPEND 15
130 #define BCM63XX_SPI_MAX_CS 8
131 #define BCM63XX_SPI_BUS_NUM 0
134 struct completion done
;
140 const unsigned long *reg_offsets
;
141 unsigned int fifo_size
;
142 unsigned int msg_type_shift
;
143 unsigned int msg_ctl_width
;
147 const u8 __iomem
*rx_io
;
150 struct platform_device
*pdev
;
153 static inline u8
bcm_spi_readb(struct bcm63xx_spi
*bs
,
156 return readb(bs
->regs
+ bs
->reg_offsets
[offset
]);
159 static inline u16
bcm_spi_readw(struct bcm63xx_spi
*bs
,
162 #ifdef CONFIG_CPU_BIG_ENDIAN
163 return ioread16be(bs
->regs
+ bs
->reg_offsets
[offset
]);
165 return readw(bs
->regs
+ bs
->reg_offsets
[offset
]);
169 static inline void bcm_spi_writeb(struct bcm63xx_spi
*bs
,
170 u8 value
, unsigned int offset
)
172 writeb(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
175 static inline void bcm_spi_writew(struct bcm63xx_spi
*bs
,
176 u16 value
, unsigned int offset
)
178 #ifdef CONFIG_CPU_BIG_ENDIAN
179 iowrite16be(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
181 writew(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
185 static const unsigned int bcm63xx_spi_freq_table
[SPI_CLK_MASK
][2] = {
186 { 20000000, SPI_CLK_20MHZ
},
187 { 12500000, SPI_CLK_12_50MHZ
},
188 { 6250000, SPI_CLK_6_250MHZ
},
189 { 3125000, SPI_CLK_3_125MHZ
},
190 { 1563000, SPI_CLK_1_563MHZ
},
191 { 781000, SPI_CLK_0_781MHZ
},
192 { 391000, SPI_CLK_0_391MHZ
}
195 static void bcm63xx_spi_setup_transfer(struct spi_device
*spi
,
196 struct spi_transfer
*t
)
198 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
202 /* Default to lowest clock configuration */
203 clk_cfg
= SPI_CLK_0_391MHZ
;
205 /* Find the closest clock configuration */
206 for (i
= 0; i
< SPI_CLK_MASK
; i
++) {
207 if (t
->speed_hz
>= bcm63xx_spi_freq_table
[i
][0]) {
208 clk_cfg
= bcm63xx_spi_freq_table
[i
][1];
213 /* clear existing clock configuration bits of the register */
214 reg
= bcm_spi_readb(bs
, SPI_CLK_CFG
);
215 reg
&= ~SPI_CLK_MASK
;
218 bcm_spi_writeb(bs
, reg
, SPI_CLK_CFG
);
219 dev_dbg(&spi
->dev
, "Setting clock register to %02x (hz %d)\n",
220 clk_cfg
, t
->speed_hz
);
223 /* the spi->mode bits understood by this driver: */
224 #define MODEBITS (SPI_CPOL | SPI_CPHA)
226 static int bcm63xx_txrx_bufs(struct spi_device
*spi
, struct spi_transfer
*first
,
227 unsigned int num_transfers
)
229 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
232 unsigned int i
, timeout
= 0, prepend_len
= 0, len
= 0;
233 struct spi_transfer
*t
= first
;
237 /* Disable the CMD_DONE interrupt */
238 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
240 dev_dbg(&spi
->dev
, "txrx: tx %p, rx %p, len %d\n",
241 t
->tx_buf
, t
->rx_buf
, t
->len
);
243 if (num_transfers
> 1 && t
->tx_buf
&& t
->len
<= BCM63XX_SPI_MAX_PREPEND
)
244 prepend_len
= t
->len
;
246 /* prepare the buffer */
247 for (i
= 0; i
< num_transfers
; i
++) {
250 memcpy_toio(bs
->tx_io
+ len
, t
->tx_buf
, t
->len
);
252 /* don't prepend more than one tx */
259 /* prepend is half-duplex write only */
266 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
270 reinit_completion(&bs
->done
);
272 /* Fill in the Message control register */
273 msg_ctl
= (len
<< SPI_BYTE_CNT_SHIFT
);
275 if (do_rx
&& do_tx
&& prepend_len
== 0)
276 msg_ctl
|= (SPI_FD_RW
<< bs
->msg_type_shift
);
278 msg_ctl
|= (SPI_HD_R
<< bs
->msg_type_shift
);
280 msg_ctl
|= (SPI_HD_W
<< bs
->msg_type_shift
);
282 switch (bs
->msg_ctl_width
) {
284 bcm_spi_writeb(bs
, msg_ctl
, SPI_MSG_CTL
);
287 bcm_spi_writew(bs
, msg_ctl
, SPI_MSG_CTL
);
291 /* Issue the transfer */
292 cmd
= SPI_CMD_START_IMMEDIATE
;
293 cmd
|= (prepend_len
<< SPI_CMD_PREPEND_BYTE_CNT_SHIFT
);
294 cmd
|= (spi
->chip_select
<< SPI_CMD_DEVICE_ID_SHIFT
);
295 bcm_spi_writew(bs
, cmd
, SPI_CMD
);
297 /* Enable the CMD_DONE interrupt */
298 bcm_spi_writeb(bs
, SPI_INTR_CMD_DONE
, SPI_INT_MASK
);
300 timeout
= wait_for_completion_timeout(&bs
->done
, HZ
);
309 /* Read out all the data */
310 for (i
= 0; i
< num_transfers
; i
++) {
312 memcpy_fromio(t
->rx_buf
, bs
->rx_io
+ len
, t
->len
);
314 if (t
!= first
|| prepend_len
== 0)
317 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
324 static int bcm63xx_spi_transfer_one(struct spi_master
*master
,
325 struct spi_message
*m
)
327 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
328 struct spi_transfer
*t
, *first
= NULL
;
329 struct spi_device
*spi
= m
->spi
;
331 unsigned int n_transfers
= 0, total_len
= 0;
332 bool can_use_prepend
= false;
335 * This SPI controller does not support keeping CS active after a
337 * Work around this by merging as many transfers we can into one big
338 * full-duplex transfers.
340 list_for_each_entry(t
, &m
->transfers
, transfer_list
) {
347 if (n_transfers
== 2 && !first
->rx_buf
&& !t
->tx_buf
&&
348 first
->len
<= BCM63XX_SPI_MAX_PREPEND
)
349 can_use_prepend
= true;
350 else if (can_use_prepend
&& t
->tx_buf
)
351 can_use_prepend
= false;
353 /* we can only transfer one fifo worth of data */
354 if ((can_use_prepend
&&
355 total_len
> (bs
->fifo_size
+ BCM63XX_SPI_MAX_PREPEND
)) ||
356 (!can_use_prepend
&& total_len
> bs
->fifo_size
)) {
357 dev_err(&spi
->dev
, "unable to do transfers larger than FIFO size (%i > %i)\n",
358 total_len
, bs
->fifo_size
);
363 /* all combined transfers have to have the same speed */
364 if (t
->speed_hz
!= first
->speed_hz
) {
365 dev_err(&spi
->dev
, "unable to change speed between transfers\n");
370 /* CS will be deasserted directly after transfer */
371 if (t
->delay_usecs
|| t
->delay
.value
) {
372 dev_err(&spi
->dev
, "unable to keep CS asserted after transfer\n");
378 list_is_last(&t
->transfer_list
, &m
->transfers
)) {
379 /* configure adapter for a new transfer */
380 bcm63xx_spi_setup_transfer(spi
, first
);
383 status
= bcm63xx_txrx_bufs(spi
, first
, n_transfers
);
387 m
->actual_length
+= total_len
;
392 can_use_prepend
= false;
397 spi_finalize_current_message(master
);
402 /* This driver supports single master mode only. Hence
403 * CMD_DONE is the only interrupt we care about
405 static irqreturn_t
bcm63xx_spi_interrupt(int irq
, void *dev_id
)
407 struct spi_master
*master
= (struct spi_master
*)dev_id
;
408 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
411 /* Read interupts and clear them immediately */
412 intr
= bcm_spi_readb(bs
, SPI_INT_STATUS
);
413 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
414 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
416 /* A transfer completed */
417 if (intr
& SPI_INTR_CMD_DONE
)
423 static size_t bcm63xx_spi_max_length(struct spi_device
*spi
)
425 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
427 return bs
->fifo_size
;
430 static const unsigned long bcm6348_spi_reg_offsets
[] = {
431 [SPI_CMD
] = SPI_6348_CMD
,
432 [SPI_INT_STATUS
] = SPI_6348_INT_STATUS
,
433 [SPI_INT_MASK_ST
] = SPI_6348_INT_MASK_ST
,
434 [SPI_INT_MASK
] = SPI_6348_INT_MASK
,
435 [SPI_ST
] = SPI_6348_ST
,
436 [SPI_CLK_CFG
] = SPI_6348_CLK_CFG
,
437 [SPI_FILL_BYTE
] = SPI_6348_FILL_BYTE
,
438 [SPI_MSG_TAIL
] = SPI_6348_MSG_TAIL
,
439 [SPI_RX_TAIL
] = SPI_6348_RX_TAIL
,
440 [SPI_MSG_CTL
] = SPI_6348_MSG_CTL
,
441 [SPI_MSG_DATA
] = SPI_6348_MSG_DATA
,
442 [SPI_RX_DATA
] = SPI_6348_RX_DATA
,
443 [SPI_MSG_TYPE_SHIFT
] = SPI_6348_MSG_TYPE_SHIFT
,
444 [SPI_MSG_CTL_WIDTH
] = SPI_6348_MSG_CTL_WIDTH
,
445 [SPI_MSG_DATA_SIZE
] = SPI_6348_MSG_DATA_SIZE
,
448 static const unsigned long bcm6358_spi_reg_offsets
[] = {
449 [SPI_CMD
] = SPI_6358_CMD
,
450 [SPI_INT_STATUS
] = SPI_6358_INT_STATUS
,
451 [SPI_INT_MASK_ST
] = SPI_6358_INT_MASK_ST
,
452 [SPI_INT_MASK
] = SPI_6358_INT_MASK
,
453 [SPI_ST
] = SPI_6358_ST
,
454 [SPI_CLK_CFG
] = SPI_6358_CLK_CFG
,
455 [SPI_FILL_BYTE
] = SPI_6358_FILL_BYTE
,
456 [SPI_MSG_TAIL
] = SPI_6358_MSG_TAIL
,
457 [SPI_RX_TAIL
] = SPI_6358_RX_TAIL
,
458 [SPI_MSG_CTL
] = SPI_6358_MSG_CTL
,
459 [SPI_MSG_DATA
] = SPI_6358_MSG_DATA
,
460 [SPI_RX_DATA
] = SPI_6358_RX_DATA
,
461 [SPI_MSG_TYPE_SHIFT
] = SPI_6358_MSG_TYPE_SHIFT
,
462 [SPI_MSG_CTL_WIDTH
] = SPI_6358_MSG_CTL_WIDTH
,
463 [SPI_MSG_DATA_SIZE
] = SPI_6358_MSG_DATA_SIZE
,
466 static const struct platform_device_id bcm63xx_spi_dev_match
[] = {
468 .name
= "bcm6348-spi",
469 .driver_data
= (unsigned long)bcm6348_spi_reg_offsets
,
472 .name
= "bcm6358-spi",
473 .driver_data
= (unsigned long)bcm6358_spi_reg_offsets
,
479 static const struct of_device_id bcm63xx_spi_of_match
[] = {
480 { .compatible
= "brcm,bcm6348-spi", .data
= &bcm6348_spi_reg_offsets
},
481 { .compatible
= "brcm,bcm6358-spi", .data
= &bcm6358_spi_reg_offsets
},
485 static int bcm63xx_spi_probe(struct platform_device
*pdev
)
488 const unsigned long *bcm63xx_spireg
;
489 struct device
*dev
= &pdev
->dev
;
491 struct spi_master
*master
;
493 struct bcm63xx_spi
*bs
;
495 u32 num_cs
= BCM63XX_SPI_MAX_CS
;
498 const struct of_device_id
*match
;
500 match
= of_match_node(bcm63xx_spi_of_match
, dev
->of_node
);
503 bcm63xx_spireg
= match
->data
;
505 of_property_read_u32(dev
->of_node
, "num-cs", &num_cs
);
506 if (num_cs
> BCM63XX_SPI_MAX_CS
) {
507 dev_warn(dev
, "unsupported number of cs (%i), reducing to 8\n",
509 num_cs
= BCM63XX_SPI_MAX_CS
;
513 } else if (pdev
->id_entry
->driver_data
) {
514 const struct platform_device_id
*match
= pdev
->id_entry
;
516 bcm63xx_spireg
= (const unsigned long *)match
->driver_data
;
517 bus_num
= BCM63XX_SPI_BUS_NUM
;
522 irq
= platform_get_irq(pdev
, 0);
526 clk
= devm_clk_get(dev
, "spi");
528 dev_err(dev
, "no clock for device\n");
532 master
= spi_alloc_master(dev
, sizeof(*bs
));
534 dev_err(dev
, "out of memory\n");
538 bs
= spi_master_get_devdata(master
);
539 init_completion(&bs
->done
);
541 platform_set_drvdata(pdev
, master
);
544 r
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
545 bs
->regs
= devm_ioremap_resource(&pdev
->dev
, r
);
546 if (IS_ERR(bs
->regs
)) {
547 ret
= PTR_ERR(bs
->regs
);
553 bs
->reg_offsets
= bcm63xx_spireg
;
554 bs
->fifo_size
= bs
->reg_offsets
[SPI_MSG_DATA_SIZE
];
556 ret
= devm_request_irq(&pdev
->dev
, irq
, bcm63xx_spi_interrupt
, 0,
559 dev_err(dev
, "unable to request irq\n");
563 master
->dev
.of_node
= dev
->of_node
;
564 master
->bus_num
= bus_num
;
565 master
->num_chipselect
= num_cs
;
566 master
->transfer_one_message
= bcm63xx_spi_transfer_one
;
567 master
->mode_bits
= MODEBITS
;
568 master
->bits_per_word_mask
= SPI_BPW_MASK(8);
569 master
->max_transfer_size
= bcm63xx_spi_max_length
;
570 master
->max_message_size
= bcm63xx_spi_max_length
;
571 master
->auto_runtime_pm
= true;
572 bs
->msg_type_shift
= bs
->reg_offsets
[SPI_MSG_TYPE_SHIFT
];
573 bs
->msg_ctl_width
= bs
->reg_offsets
[SPI_MSG_CTL_WIDTH
];
574 bs
->tx_io
= (u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_MSG_DATA
]);
575 bs
->rx_io
= (const u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_RX_DATA
]);
577 /* Initialize hardware */
578 ret
= clk_prepare_enable(bs
->clk
);
582 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
584 /* register and we are done */
585 ret
= devm_spi_register_master(dev
, master
);
587 dev_err(dev
, "spi register failed\n");
588 goto out_clk_disable
;
591 dev_info(dev
, "at %pr (irq %d, FIFOs size %d)\n",
592 r
, irq
, bs
->fifo_size
);
597 clk_disable_unprepare(clk
);
599 spi_master_put(master
);
603 static int bcm63xx_spi_remove(struct platform_device
*pdev
)
605 struct spi_master
*master
= platform_get_drvdata(pdev
);
606 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
608 /* reset spi block */
609 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
612 clk_disable_unprepare(bs
->clk
);
617 #ifdef CONFIG_PM_SLEEP
618 static int bcm63xx_spi_suspend(struct device
*dev
)
620 struct spi_master
*master
= dev_get_drvdata(dev
);
621 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
623 spi_master_suspend(master
);
625 clk_disable_unprepare(bs
->clk
);
630 static int bcm63xx_spi_resume(struct device
*dev
)
632 struct spi_master
*master
= dev_get_drvdata(dev
);
633 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
636 ret
= clk_prepare_enable(bs
->clk
);
640 spi_master_resume(master
);
646 static const struct dev_pm_ops bcm63xx_spi_pm_ops
= {
647 SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend
, bcm63xx_spi_resume
)
650 static struct platform_driver bcm63xx_spi_driver
= {
652 .name
= "bcm63xx-spi",
653 .pm
= &bcm63xx_spi_pm_ops
,
654 .of_match_table
= bcm63xx_spi_of_match
,
656 .id_table
= bcm63xx_spi_dev_match
,
657 .probe
= bcm63xx_spi_probe
,
658 .remove
= bcm63xx_spi_remove
,
661 module_platform_driver(bcm63xx_spi_driver
);
663 MODULE_ALIAS("platform:bcm63xx_spi");
664 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
665 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
666 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
667 MODULE_LICENSE("GPL");