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>
21 #include <linux/reset.h>
23 /* BCM 6338/6348 SPI core */
24 #define SPI_6348_RSET_SIZE 64
25 #define SPI_6348_CMD 0x00 /* 16-bits register */
26 #define SPI_6348_INT_STATUS 0x02
27 #define SPI_6348_INT_MASK_ST 0x03
28 #define SPI_6348_INT_MASK 0x04
29 #define SPI_6348_ST 0x05
30 #define SPI_6348_CLK_CFG 0x06
31 #define SPI_6348_FILL_BYTE 0x07
32 #define SPI_6348_MSG_TAIL 0x09
33 #define SPI_6348_RX_TAIL 0x0b
34 #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
35 #define SPI_6348_MSG_CTL_WIDTH 8
36 #define SPI_6348_MSG_DATA 0x41
37 #define SPI_6348_MSG_DATA_SIZE 0x3f
38 #define SPI_6348_RX_DATA 0x80
39 #define SPI_6348_RX_DATA_SIZE 0x3f
41 /* BCM 3368/6358/6262/6368 SPI core */
42 #define SPI_6358_RSET_SIZE 1804
43 #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
44 #define SPI_6358_MSG_CTL_WIDTH 16
45 #define SPI_6358_MSG_DATA 0x02
46 #define SPI_6358_MSG_DATA_SIZE 0x21e
47 #define SPI_6358_RX_DATA 0x400
48 #define SPI_6358_RX_DATA_SIZE 0x220
49 #define SPI_6358_CMD 0x700 /* 16-bits register */
50 #define SPI_6358_INT_STATUS 0x702
51 #define SPI_6358_INT_MASK_ST 0x703
52 #define SPI_6358_INT_MASK 0x704
53 #define SPI_6358_ST 0x705
54 #define SPI_6358_CLK_CFG 0x706
55 #define SPI_6358_FILL_BYTE 0x707
56 #define SPI_6358_MSG_TAIL 0x709
57 #define SPI_6358_RX_TAIL 0x70B
59 /* Shared SPI definitions */
61 /* Message configuration */
62 #define SPI_FD_RW 0x00
65 #define SPI_BYTE_CNT_SHIFT 0
66 #define SPI_6348_MSG_TYPE_SHIFT 6
67 #define SPI_6358_MSG_TYPE_SHIFT 14
70 #define SPI_CMD_NOOP 0x00
71 #define SPI_CMD_SOFT_RESET 0x01
72 #define SPI_CMD_HARD_RESET 0x02
73 #define SPI_CMD_START_IMMEDIATE 0x03
74 #define SPI_CMD_COMMAND_SHIFT 0
75 #define SPI_CMD_COMMAND_MASK 0x000f
76 #define SPI_CMD_DEVICE_ID_SHIFT 4
77 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
78 #define SPI_CMD_ONE_BYTE_SHIFT 11
79 #define SPI_CMD_ONE_WIRE_SHIFT 12
80 #define SPI_DEV_ID_0 0
81 #define SPI_DEV_ID_1 1
82 #define SPI_DEV_ID_2 2
83 #define SPI_DEV_ID_3 3
86 #define SPI_INTR_CMD_DONE 0x01
87 #define SPI_INTR_RX_OVERFLOW 0x02
88 #define SPI_INTR_TX_UNDERFLOW 0x04
89 #define SPI_INTR_TX_OVERFLOW 0x08
90 #define SPI_INTR_RX_UNDERFLOW 0x10
91 #define SPI_INTR_CLEAR_ALL 0x1f
94 #define SPI_RX_EMPTY 0x02
95 #define SPI_CMD_BUSY 0x04
96 #define SPI_SERIAL_BUSY 0x08
98 /* Clock configuration */
99 #define SPI_CLK_20MHZ 0x00
100 #define SPI_CLK_0_391MHZ 0x01
101 #define SPI_CLK_0_781MHZ 0x02 /* default */
102 #define SPI_CLK_1_563MHZ 0x03
103 #define SPI_CLK_3_125MHZ 0x04
104 #define SPI_CLK_6_250MHZ 0x05
105 #define SPI_CLK_12_50MHZ 0x06
106 #define SPI_CLK_MASK 0x07
107 #define SPI_SSOFFTIME_MASK 0x38
108 #define SPI_SSOFFTIME_SHIFT 3
109 #define SPI_BYTE_SWAP 0x80
111 enum bcm63xx_regs_spi
{
129 #define BCM63XX_SPI_MAX_PREPEND 7
131 #define BCM63XX_SPI_MAX_CS 8
132 #define BCM63XX_SPI_BUS_NUM 0
135 struct completion done
;
141 const unsigned long *reg_offsets
;
142 unsigned int fifo_size
;
143 unsigned int msg_type_shift
;
144 unsigned int msg_ctl_width
;
148 const u8 __iomem
*rx_io
;
151 struct platform_device
*pdev
;
154 static inline u8
bcm_spi_readb(struct bcm63xx_spi
*bs
,
157 return readb(bs
->regs
+ bs
->reg_offsets
[offset
]);
160 static inline void bcm_spi_writeb(struct bcm63xx_spi
*bs
,
161 u8 value
, unsigned int offset
)
163 writeb(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
166 static inline void bcm_spi_writew(struct bcm63xx_spi
*bs
,
167 u16 value
, unsigned int offset
)
169 #ifdef CONFIG_CPU_BIG_ENDIAN
170 iowrite16be(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
172 writew(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
176 static const unsigned int bcm63xx_spi_freq_table
[SPI_CLK_MASK
][2] = {
177 { 20000000, SPI_CLK_20MHZ
},
178 { 12500000, SPI_CLK_12_50MHZ
},
179 { 6250000, SPI_CLK_6_250MHZ
},
180 { 3125000, SPI_CLK_3_125MHZ
},
181 { 1563000, SPI_CLK_1_563MHZ
},
182 { 781000, SPI_CLK_0_781MHZ
},
183 { 391000, SPI_CLK_0_391MHZ
}
186 static void bcm63xx_spi_setup_transfer(struct spi_device
*spi
,
187 struct spi_transfer
*t
)
189 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(spi
->controller
);
193 /* Default to lowest clock configuration */
194 clk_cfg
= SPI_CLK_0_391MHZ
;
196 /* Find the closest clock configuration */
197 for (i
= 0; i
< SPI_CLK_MASK
; i
++) {
198 if (t
->speed_hz
>= bcm63xx_spi_freq_table
[i
][0]) {
199 clk_cfg
= bcm63xx_spi_freq_table
[i
][1];
204 /* clear existing clock configuration bits of the register */
205 reg
= bcm_spi_readb(bs
, SPI_CLK_CFG
);
206 reg
&= ~SPI_CLK_MASK
;
209 bcm_spi_writeb(bs
, reg
, SPI_CLK_CFG
);
210 dev_dbg(&spi
->dev
, "Setting clock register to %02x (hz %d)\n",
211 clk_cfg
, t
->speed_hz
);
214 /* the spi->mode bits understood by this driver: */
215 #define MODEBITS (SPI_CPOL | SPI_CPHA)
217 static int bcm63xx_txrx_bufs(struct spi_device
*spi
, struct spi_transfer
*first
,
218 unsigned int num_transfers
)
220 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(spi
->controller
);
223 unsigned int i
, timeout
= 0, prepend_len
= 0, len
= 0;
224 struct spi_transfer
*t
= first
;
228 /* Disable the CMD_DONE interrupt */
229 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
231 dev_dbg(&spi
->dev
, "txrx: tx %p, rx %p, len %d\n",
232 t
->tx_buf
, t
->rx_buf
, t
->len
);
234 if (num_transfers
> 1 && t
->tx_buf
&& t
->len
<= BCM63XX_SPI_MAX_PREPEND
)
235 prepend_len
= t
->len
;
237 /* prepare the buffer */
238 for (i
= 0; i
< num_transfers
; i
++) {
241 memcpy_toio(bs
->tx_io
+ len
, t
->tx_buf
, t
->len
);
243 /* don't prepend more than one tx */
250 /* prepend is half-duplex write only */
257 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
261 reinit_completion(&bs
->done
);
263 /* Fill in the Message control register */
264 msg_ctl
= (len
<< SPI_BYTE_CNT_SHIFT
);
266 if (do_rx
&& do_tx
&& prepend_len
== 0)
267 msg_ctl
|= (SPI_FD_RW
<< bs
->msg_type_shift
);
269 msg_ctl
|= (SPI_HD_R
<< bs
->msg_type_shift
);
271 msg_ctl
|= (SPI_HD_W
<< bs
->msg_type_shift
);
273 switch (bs
->msg_ctl_width
) {
275 bcm_spi_writeb(bs
, msg_ctl
, SPI_MSG_CTL
);
278 bcm_spi_writew(bs
, msg_ctl
, SPI_MSG_CTL
);
282 /* Issue the transfer */
283 cmd
= SPI_CMD_START_IMMEDIATE
;
284 cmd
|= (prepend_len
<< SPI_CMD_PREPEND_BYTE_CNT_SHIFT
);
285 cmd
|= (spi_get_chipselect(spi
, 0) << SPI_CMD_DEVICE_ID_SHIFT
);
286 bcm_spi_writew(bs
, cmd
, SPI_CMD
);
288 /* Enable the CMD_DONE interrupt */
289 bcm_spi_writeb(bs
, SPI_INTR_CMD_DONE
, SPI_INT_MASK
);
291 timeout
= wait_for_completion_timeout(&bs
->done
, HZ
);
300 /* Read out all the data */
301 for (i
= 0; i
< num_transfers
; i
++) {
303 memcpy_fromio(t
->rx_buf
, bs
->rx_io
+ len
, t
->len
);
305 if (t
!= first
|| prepend_len
== 0)
308 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
315 static int bcm63xx_spi_transfer_one(struct spi_controller
*host
,
316 struct spi_message
*m
)
318 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(host
);
319 struct spi_transfer
*t
, *first
= NULL
;
320 struct spi_device
*spi
= m
->spi
;
322 unsigned int n_transfers
= 0, total_len
= 0;
323 bool can_use_prepend
= false;
326 * This SPI controller does not support keeping CS active after a
328 * Work around this by merging as many transfers we can into one big
329 * full-duplex transfers.
331 list_for_each_entry(t
, &m
->transfers
, transfer_list
) {
338 if (n_transfers
== 2 && !first
->rx_buf
&& !t
->tx_buf
&&
339 first
->len
<= BCM63XX_SPI_MAX_PREPEND
)
340 can_use_prepend
= true;
341 else if (can_use_prepend
&& t
->tx_buf
)
342 can_use_prepend
= false;
344 /* we can only transfer one fifo worth of data */
345 if ((can_use_prepend
&&
346 total_len
> (bs
->fifo_size
+ BCM63XX_SPI_MAX_PREPEND
)) ||
347 (!can_use_prepend
&& total_len
> bs
->fifo_size
)) {
348 dev_err(&spi
->dev
, "unable to do transfers larger than FIFO size (%i > %i)\n",
349 total_len
, bs
->fifo_size
);
354 /* all combined transfers have to have the same speed */
355 if (t
->speed_hz
!= first
->speed_hz
) {
356 dev_err(&spi
->dev
, "unable to change speed between transfers\n");
361 /* CS will be deasserted directly after transfer */
362 if (t
->delay
.value
) {
363 dev_err(&spi
->dev
, "unable to keep CS asserted after transfer\n");
369 list_is_last(&t
->transfer_list
, &m
->transfers
)) {
370 /* configure adapter for a new transfer */
371 bcm63xx_spi_setup_transfer(spi
, first
);
374 status
= bcm63xx_txrx_bufs(spi
, first
, n_transfers
);
378 m
->actual_length
+= total_len
;
383 can_use_prepend
= false;
388 spi_finalize_current_message(host
);
393 /* This driver supports single host mode only. Hence
394 * CMD_DONE is the only interrupt we care about
396 static irqreturn_t
bcm63xx_spi_interrupt(int irq
, void *dev_id
)
398 struct spi_controller
*host
= (struct spi_controller
*)dev_id
;
399 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(host
);
402 /* Read interupts and clear them immediately */
403 intr
= bcm_spi_readb(bs
, SPI_INT_STATUS
);
404 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
405 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
407 /* A transfer completed */
408 if (intr
& SPI_INTR_CMD_DONE
)
414 static size_t bcm63xx_spi_max_length(struct spi_device
*spi
)
416 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(spi
->controller
);
418 return bs
->fifo_size
;
421 static const unsigned long bcm6348_spi_reg_offsets
[] = {
422 [SPI_CMD
] = SPI_6348_CMD
,
423 [SPI_INT_STATUS
] = SPI_6348_INT_STATUS
,
424 [SPI_INT_MASK_ST
] = SPI_6348_INT_MASK_ST
,
425 [SPI_INT_MASK
] = SPI_6348_INT_MASK
,
426 [SPI_ST
] = SPI_6348_ST
,
427 [SPI_CLK_CFG
] = SPI_6348_CLK_CFG
,
428 [SPI_FILL_BYTE
] = SPI_6348_FILL_BYTE
,
429 [SPI_MSG_TAIL
] = SPI_6348_MSG_TAIL
,
430 [SPI_RX_TAIL
] = SPI_6348_RX_TAIL
,
431 [SPI_MSG_CTL
] = SPI_6348_MSG_CTL
,
432 [SPI_MSG_DATA
] = SPI_6348_MSG_DATA
,
433 [SPI_RX_DATA
] = SPI_6348_RX_DATA
,
434 [SPI_MSG_TYPE_SHIFT
] = SPI_6348_MSG_TYPE_SHIFT
,
435 [SPI_MSG_CTL_WIDTH
] = SPI_6348_MSG_CTL_WIDTH
,
436 [SPI_MSG_DATA_SIZE
] = SPI_6348_MSG_DATA_SIZE
,
439 static const unsigned long bcm6358_spi_reg_offsets
[] = {
440 [SPI_CMD
] = SPI_6358_CMD
,
441 [SPI_INT_STATUS
] = SPI_6358_INT_STATUS
,
442 [SPI_INT_MASK_ST
] = SPI_6358_INT_MASK_ST
,
443 [SPI_INT_MASK
] = SPI_6358_INT_MASK
,
444 [SPI_ST
] = SPI_6358_ST
,
445 [SPI_CLK_CFG
] = SPI_6358_CLK_CFG
,
446 [SPI_FILL_BYTE
] = SPI_6358_FILL_BYTE
,
447 [SPI_MSG_TAIL
] = SPI_6358_MSG_TAIL
,
448 [SPI_RX_TAIL
] = SPI_6358_RX_TAIL
,
449 [SPI_MSG_CTL
] = SPI_6358_MSG_CTL
,
450 [SPI_MSG_DATA
] = SPI_6358_MSG_DATA
,
451 [SPI_RX_DATA
] = SPI_6358_RX_DATA
,
452 [SPI_MSG_TYPE_SHIFT
] = SPI_6358_MSG_TYPE_SHIFT
,
453 [SPI_MSG_CTL_WIDTH
] = SPI_6358_MSG_CTL_WIDTH
,
454 [SPI_MSG_DATA_SIZE
] = SPI_6358_MSG_DATA_SIZE
,
457 static const struct platform_device_id bcm63xx_spi_dev_match
[] = {
459 .name
= "bcm6348-spi",
460 .driver_data
= (unsigned long)bcm6348_spi_reg_offsets
,
463 .name
= "bcm6358-spi",
464 .driver_data
= (unsigned long)bcm6358_spi_reg_offsets
,
469 MODULE_DEVICE_TABLE(platform
, bcm63xx_spi_dev_match
);
471 static const struct of_device_id bcm63xx_spi_of_match
[] = {
472 { .compatible
= "brcm,bcm6348-spi", .data
= &bcm6348_spi_reg_offsets
},
473 { .compatible
= "brcm,bcm6358-spi", .data
= &bcm6358_spi_reg_offsets
},
476 MODULE_DEVICE_TABLE(of
, bcm63xx_spi_of_match
);
478 static int bcm63xx_spi_probe(struct platform_device
*pdev
)
481 const unsigned long *bcm63xx_spireg
;
482 struct device
*dev
= &pdev
->dev
;
484 struct spi_controller
*host
;
486 struct bcm63xx_spi
*bs
;
488 u32 num_cs
= BCM63XX_SPI_MAX_CS
;
489 struct reset_control
*reset
;
492 const struct of_device_id
*match
;
494 match
= of_match_node(bcm63xx_spi_of_match
, dev
->of_node
);
497 bcm63xx_spireg
= match
->data
;
499 of_property_read_u32(dev
->of_node
, "num-cs", &num_cs
);
500 if (num_cs
> BCM63XX_SPI_MAX_CS
) {
501 dev_warn(dev
, "unsupported number of cs (%i), reducing to 8\n",
503 num_cs
= BCM63XX_SPI_MAX_CS
;
507 } else if (pdev
->id_entry
->driver_data
) {
508 const struct platform_device_id
*match
= pdev
->id_entry
;
510 bcm63xx_spireg
= (const unsigned long *)match
->driver_data
;
511 bus_num
= BCM63XX_SPI_BUS_NUM
;
516 irq
= platform_get_irq(pdev
, 0);
520 clk
= devm_clk_get(dev
, "spi");
522 dev_err(dev
, "no clock for device\n");
526 reset
= devm_reset_control_get_optional_exclusive(dev
, NULL
);
528 return PTR_ERR(reset
);
530 host
= spi_alloc_host(dev
, sizeof(*bs
));
532 dev_err(dev
, "out of memory\n");
536 bs
= spi_controller_get_devdata(host
);
537 init_completion(&bs
->done
);
539 platform_set_drvdata(pdev
, host
);
542 bs
->regs
= devm_platform_get_and_ioremap_resource(pdev
, 0, &r
);
543 if (IS_ERR(bs
->regs
)) {
544 ret
= PTR_ERR(bs
->regs
);
550 bs
->reg_offsets
= bcm63xx_spireg
;
551 bs
->fifo_size
= bs
->reg_offsets
[SPI_MSG_DATA_SIZE
];
553 ret
= devm_request_irq(&pdev
->dev
, irq
, bcm63xx_spi_interrupt
, 0,
556 dev_err(dev
, "unable to request irq\n");
560 host
->dev
.of_node
= dev
->of_node
;
561 host
->bus_num
= bus_num
;
562 host
->num_chipselect
= num_cs
;
563 host
->transfer_one_message
= bcm63xx_spi_transfer_one
;
564 host
->mode_bits
= MODEBITS
;
565 host
->bits_per_word_mask
= SPI_BPW_MASK(8);
566 host
->max_transfer_size
= bcm63xx_spi_max_length
;
567 host
->max_message_size
= bcm63xx_spi_max_length
;
568 host
->auto_runtime_pm
= true;
569 bs
->msg_type_shift
= bs
->reg_offsets
[SPI_MSG_TYPE_SHIFT
];
570 bs
->msg_ctl_width
= bs
->reg_offsets
[SPI_MSG_CTL_WIDTH
];
571 bs
->tx_io
= (u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_MSG_DATA
]);
572 bs
->rx_io
= (const u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_RX_DATA
]);
574 /* Initialize hardware */
575 ret
= clk_prepare_enable(bs
->clk
);
579 ret
= reset_control_reset(reset
);
581 dev_err(dev
, "unable to reset device: %d\n", ret
);
582 goto out_clk_disable
;
585 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
587 ret
= devm_pm_runtime_enable(&pdev
->dev
);
589 goto out_clk_disable
;
591 /* register and we are done */
592 ret
= devm_spi_register_controller(dev
, host
);
594 dev_err(dev
, "spi register failed\n");
595 goto out_clk_disable
;
598 dev_info(dev
, "at %pr (irq %d, FIFOs size %d)\n",
599 r
, irq
, bs
->fifo_size
);
604 clk_disable_unprepare(clk
);
606 spi_controller_put(host
);
610 static void bcm63xx_spi_remove(struct platform_device
*pdev
)
612 struct spi_controller
*host
= platform_get_drvdata(pdev
);
613 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(host
);
615 /* reset spi block */
616 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
619 clk_disable_unprepare(bs
->clk
);
622 static int bcm63xx_spi_suspend(struct device
*dev
)
624 struct spi_controller
*host
= dev_get_drvdata(dev
);
625 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(host
);
627 spi_controller_suspend(host
);
629 clk_disable_unprepare(bs
->clk
);
634 static int bcm63xx_spi_resume(struct device
*dev
)
636 struct spi_controller
*host
= dev_get_drvdata(dev
);
637 struct bcm63xx_spi
*bs
= spi_controller_get_devdata(host
);
640 ret
= clk_prepare_enable(bs
->clk
);
644 spi_controller_resume(host
);
649 static DEFINE_SIMPLE_DEV_PM_OPS(bcm63xx_spi_pm_ops
, bcm63xx_spi_suspend
, bcm63xx_spi_resume
);
651 static struct platform_driver bcm63xx_spi_driver
= {
653 .name
= "bcm63xx-spi",
654 .pm
= &bcm63xx_spi_pm_ops
,
655 .of_match_table
= bcm63xx_spi_of_match
,
657 .id_table
= bcm63xx_spi_dev_match
,
658 .probe
= bcm63xx_spi_probe
,
659 .remove
= bcm63xx_spi_remove
,
662 module_platform_driver(bcm63xx_spi_driver
);
664 MODULE_ALIAS("platform:bcm63xx_spi");
665 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
666 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
667 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
668 MODULE_LICENSE("GPL");