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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 *
5 * Copyright (C) 2008-2012 ST-Ericsson AB
6 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
7 *
8 * Author: Linus Walleij <linus.walleij@stericsson.com>
9 *
10 * Initial version inspired by:
11 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
12 * Initial adoption to PL022 by:
13 * Sachin Verma <sachin.verma@st.com>
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/device.h>
19#include <linux/ioport.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/spi/spi.h>
23#include <linux/delay.h>
24#include <linux/clk.h>
25#include <linux/err.h>
26#include <linux/amba/bus.h>
27#include <linux/amba/pl022.h>
28#include <linux/io.h>
29#include <linux/slab.h>
30#include <linux/dmaengine.h>
31#include <linux/dma-mapping.h>
32#include <linux/scatterlist.h>
33#include <linux/pm_runtime.h>
34#include <linux/of.h>
35#include <linux/pinctrl/consumer.h>
36
37/*
38 * This macro is used to define some register default values.
39 * reg is masked with mask, the OR:ed with an (again masked)
40 * val shifted sb steps to the left.
41 */
42#define SSP_WRITE_BITS(reg, val, mask, sb) \
43 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
44
45/*
46 * This macro is also used to define some default values.
47 * It will just shift val by sb steps to the left and mask
48 * the result with mask.
49 */
50#define GEN_MASK_BITS(val, mask, sb) \
51 (((val)<<(sb)) & (mask))
52
53#define DRIVE_TX 0
54#define DO_NOT_DRIVE_TX 1
55
56#define DO_NOT_QUEUE_DMA 0
57#define QUEUE_DMA 1
58
59#define RX_TRANSFER 1
60#define TX_TRANSFER 2
61
62/*
63 * Macros to access SSP Registers with their offsets
64 */
65#define SSP_CR0(r) (r + 0x000)
66#define SSP_CR1(r) (r + 0x004)
67#define SSP_DR(r) (r + 0x008)
68#define SSP_SR(r) (r + 0x00C)
69#define SSP_CPSR(r) (r + 0x010)
70#define SSP_IMSC(r) (r + 0x014)
71#define SSP_RIS(r) (r + 0x018)
72#define SSP_MIS(r) (r + 0x01C)
73#define SSP_ICR(r) (r + 0x020)
74#define SSP_DMACR(r) (r + 0x024)
75#define SSP_CSR(r) (r + 0x030) /* vendor extension */
76#define SSP_ITCR(r) (r + 0x080)
77#define SSP_ITIP(r) (r + 0x084)
78#define SSP_ITOP(r) (r + 0x088)
79#define SSP_TDR(r) (r + 0x08C)
80
81#define SSP_PID0(r) (r + 0xFE0)
82#define SSP_PID1(r) (r + 0xFE4)
83#define SSP_PID2(r) (r + 0xFE8)
84#define SSP_PID3(r) (r + 0xFEC)
85
86#define SSP_CID0(r) (r + 0xFF0)
87#define SSP_CID1(r) (r + 0xFF4)
88#define SSP_CID2(r) (r + 0xFF8)
89#define SSP_CID3(r) (r + 0xFFC)
90
91/*
92 * SSP Control Register 0 - SSP_CR0
93 */
94#define SSP_CR0_MASK_DSS (0x0FUL << 0)
95#define SSP_CR0_MASK_FRF (0x3UL << 4)
96#define SSP_CR0_MASK_SPO (0x1UL << 6)
97#define SSP_CR0_MASK_SPH (0x1UL << 7)
98#define SSP_CR0_MASK_SCR (0xFFUL << 8)
99
100/*
101 * The ST version of this block moves som bits
102 * in SSP_CR0 and extends it to 32 bits
103 */
104#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
105#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
106#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
107#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
108
109/*
110 * SSP Control Register 0 - SSP_CR1
111 */
112#define SSP_CR1_MASK_LBM (0x1UL << 0)
113#define SSP_CR1_MASK_SSE (0x1UL << 1)
114#define SSP_CR1_MASK_MS (0x1UL << 2)
115#define SSP_CR1_MASK_SOD (0x1UL << 3)
116
117/*
118 * The ST version of this block adds some bits
119 * in SSP_CR1
120 */
121#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
122#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
123#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
124#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
125#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
126/* This one is only in the PL023 variant */
127#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
128
129/*
130 * SSP Status Register - SSP_SR
131 */
132#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
133#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
134#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
135#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
136#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
137
138/*
139 * SSP Clock Prescale Register - SSP_CPSR
140 */
141#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
142
143/*
144 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
145 */
146#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
147#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
148#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
149#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
150
151/*
152 * SSP Raw Interrupt Status Register - SSP_RIS
153 */
154/* Receive Overrun Raw Interrupt status */
155#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
156/* Receive Timeout Raw Interrupt status */
157#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
158/* Receive FIFO Raw Interrupt status */
159#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
160/* Transmit FIFO Raw Interrupt status */
161#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
162
163/*
164 * SSP Masked Interrupt Status Register - SSP_MIS
165 */
166/* Receive Overrun Masked Interrupt status */
167#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
168/* Receive Timeout Masked Interrupt status */
169#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
170/* Receive FIFO Masked Interrupt status */
171#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
172/* Transmit FIFO Masked Interrupt status */
173#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
174
175/*
176 * SSP Interrupt Clear Register - SSP_ICR
177 */
178/* Receive Overrun Raw Clear Interrupt bit */
179#define SSP_ICR_MASK_RORIC (0x1UL << 0)
180/* Receive Timeout Clear Interrupt bit */
181#define SSP_ICR_MASK_RTIC (0x1UL << 1)
182
183/*
184 * SSP DMA Control Register - SSP_DMACR
185 */
186/* Receive DMA Enable bit */
187#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
188/* Transmit DMA Enable bit */
189#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
190
191/*
192 * SSP Chip Select Control Register - SSP_CSR
193 * (vendor extension)
194 */
195#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
196
197/*
198 * SSP Integration Test control Register - SSP_ITCR
199 */
200#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
201#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
202
203/*
204 * SSP Integration Test Input Register - SSP_ITIP
205 */
206#define ITIP_MASK_SSPRXD (0x1UL << 0)
207#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
208#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
209#define ITIP_MASK_RXDMAC (0x1UL << 3)
210#define ITIP_MASK_TXDMAC (0x1UL << 4)
211#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
212
213/*
214 * SSP Integration Test output Register - SSP_ITOP
215 */
216#define ITOP_MASK_SSPTXD (0x1UL << 0)
217#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
218#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
219#define ITOP_MASK_SSPOEn (0x1UL << 3)
220#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
221#define ITOP_MASK_RORINTR (0x1UL << 5)
222#define ITOP_MASK_RTINTR (0x1UL << 6)
223#define ITOP_MASK_RXINTR (0x1UL << 7)
224#define ITOP_MASK_TXINTR (0x1UL << 8)
225#define ITOP_MASK_INTR (0x1UL << 9)
226#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
227#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
228#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
229#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
230
231/*
232 * SSP Test Data Register - SSP_TDR
233 */
234#define TDR_MASK_TESTDATA (0xFFFFFFFF)
235
236/*
237 * Message State
238 * we use the spi_message.state (void *) pointer to
239 * hold a single state value, that's why all this
240 * (void *) casting is done here.
241 */
242#define STATE_START ((void *) 0)
243#define STATE_RUNNING ((void *) 1)
244#define STATE_DONE ((void *) 2)
245#define STATE_ERROR ((void *) -1)
246#define STATE_TIMEOUT ((void *) -2)
247
248/*
249 * SSP State - Whether Enabled or Disabled
250 */
251#define SSP_DISABLED (0)
252#define SSP_ENABLED (1)
253
254/*
255 * SSP DMA State - Whether DMA Enabled or Disabled
256 */
257#define SSP_DMA_DISABLED (0)
258#define SSP_DMA_ENABLED (1)
259
260/*
261 * SSP Clock Defaults
262 */
263#define SSP_DEFAULT_CLKRATE 0x2
264#define SSP_DEFAULT_PRESCALE 0x40
265
266/*
267 * SSP Clock Parameter ranges
268 */
269#define CPSDVR_MIN 0x02
270#define CPSDVR_MAX 0xFE
271#define SCR_MIN 0x00
272#define SCR_MAX 0xFF
273
274/*
275 * SSP Interrupt related Macros
276 */
277#define DEFAULT_SSP_REG_IMSC 0x0UL
278#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
279#define ENABLE_ALL_INTERRUPTS ( \
280 SSP_IMSC_MASK_RORIM | \
281 SSP_IMSC_MASK_RTIM | \
282 SSP_IMSC_MASK_RXIM | \
283 SSP_IMSC_MASK_TXIM \
284)
285
286#define CLEAR_ALL_INTERRUPTS 0x3
287
288#define SPI_POLLING_TIMEOUT 1000
289
290/*
291 * The type of reading going on this chip
292 */
293enum ssp_reading {
294 READING_NULL,
295 READING_U8,
296 READING_U16,
297 READING_U32
298};
299
300/*
301 * The type of writing going on this chip
302 */
303enum ssp_writing {
304 WRITING_NULL,
305 WRITING_U8,
306 WRITING_U16,
307 WRITING_U32
308};
309
310/**
311 * struct vendor_data - vendor-specific config parameters
312 * for PL022 derivates
313 * @fifodepth: depth of FIFOs (both)
314 * @max_bpw: maximum number of bits per word
315 * @unidir: supports unidirection transfers
316 * @extended_cr: 32 bit wide control register 0 with extra
317 * features and extra features in CR1 as found in the ST variants
318 * @pl023: supports a subset of the ST extensions called "PL023"
319 * @loopback: supports loopback mode
320 * @internal_cs_ctrl: supports chip select control register
321 */
322struct vendor_data {
323 int fifodepth;
324 int max_bpw;
325 bool unidir;
326 bool extended_cr;
327 bool pl023;
328 bool loopback;
329 bool internal_cs_ctrl;
330};
331
332/**
333 * struct pl022 - This is the private SSP driver data structure
334 * @adev: AMBA device model hookup
335 * @vendor: vendor data for the IP block
336 * @phybase: the physical memory where the SSP device resides
337 * @virtbase: the virtual memory where the SSP is mapped
338 * @clk: outgoing clock "SPICLK" for the SPI bus
339 * @master: SPI framework hookup
340 * @master_info: controller-specific data from machine setup
341 * @pump_transfers: Tasklet used in Interrupt Transfer mode
342 * @cur_msg: Pointer to current spi_message being processed
343 * @cur_transfer: Pointer to current spi_transfer
344 * @cur_chip: pointer to current clients chip(assigned from controller_state)
345 * @next_msg_cs_active: the next message in the queue has been examined
346 * and it was found that it uses the same chip select as the previous
347 * message, so we left it active after the previous transfer, and it's
348 * active already.
349 * @tx: current position in TX buffer to be read
350 * @tx_end: end position in TX buffer to be read
351 * @rx: current position in RX buffer to be written
352 * @rx_end: end position in RX buffer to be written
353 * @read: the type of read currently going on
354 * @write: the type of write currently going on
355 * @exp_fifo_level: expected FIFO level
356 * @rx_lev_trig: receive FIFO watermark level which triggers IRQ
357 * @tx_lev_trig: transmit FIFO watermark level which triggers IRQ
358 * @dma_rx_channel: optional channel for RX DMA
359 * @dma_tx_channel: optional channel for TX DMA
360 * @sgt_rx: scattertable for the RX transfer
361 * @sgt_tx: scattertable for the TX transfer
362 * @dummypage: a dummy page used for driving data on the bus with DMA
363 * @dma_running: indicates whether DMA is in operation
364 * @cur_cs: current chip select index
365 * @cur_gpiod: current chip select GPIO descriptor
366 */
367struct pl022 {
368 struct amba_device *adev;
369 struct vendor_data *vendor;
370 resource_size_t phybase;
371 void __iomem *virtbase;
372 struct clk *clk;
373 struct spi_master *master;
374 struct pl022_ssp_controller *master_info;
375 /* Message per-transfer pump */
376 struct tasklet_struct pump_transfers;
377 struct spi_message *cur_msg;
378 struct spi_transfer *cur_transfer;
379 struct chip_data *cur_chip;
380 bool next_msg_cs_active;
381 void *tx;
382 void *tx_end;
383 void *rx;
384 void *rx_end;
385 enum ssp_reading read;
386 enum ssp_writing write;
387 u32 exp_fifo_level;
388 enum ssp_rx_level_trig rx_lev_trig;
389 enum ssp_tx_level_trig tx_lev_trig;
390 /* DMA settings */
391#ifdef CONFIG_DMA_ENGINE
392 struct dma_chan *dma_rx_channel;
393 struct dma_chan *dma_tx_channel;
394 struct sg_table sgt_rx;
395 struct sg_table sgt_tx;
396 char *dummypage;
397 bool dma_running;
398#endif
399 int cur_cs;
400 struct gpio_desc *cur_gpiod;
401};
402
403/**
404 * struct chip_data - To maintain runtime state of SSP for each client chip
405 * @cr0: Value of control register CR0 of SSP - on later ST variants this
406 * register is 32 bits wide rather than just 16
407 * @cr1: Value of control register CR1 of SSP
408 * @dmacr: Value of DMA control Register of SSP
409 * @cpsr: Value of Clock prescale register
410 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
411 * @enable_dma: Whether to enable DMA or not
412 * @read: function ptr to be used to read when doing xfer for this chip
413 * @write: function ptr to be used to write when doing xfer for this chip
414 * @xfer_type: polling/interrupt/DMA
415 *
416 * Runtime state of the SSP controller, maintained per chip,
417 * This would be set according to the current message that would be served
418 */
419struct chip_data {
420 u32 cr0;
421 u16 cr1;
422 u16 dmacr;
423 u16 cpsr;
424 u8 n_bytes;
425 bool enable_dma;
426 enum ssp_reading read;
427 enum ssp_writing write;
428 int xfer_type;
429};
430
431/**
432 * internal_cs_control - Control chip select signals via SSP_CSR.
433 * @pl022: SSP driver private data structure
434 * @command: select/delect the chip
435 *
436 * Used on controller with internal chip select control via SSP_CSR register
437 * (vendor extension). Each of the 5 LSB in the register controls one chip
438 * select signal.
439 */
440static void internal_cs_control(struct pl022 *pl022, u32 command)
441{
442 u32 tmp;
443
444 tmp = readw(SSP_CSR(pl022->virtbase));
445 if (command == SSP_CHIP_SELECT)
446 tmp &= ~BIT(pl022->cur_cs);
447 else
448 tmp |= BIT(pl022->cur_cs);
449 writew(tmp, SSP_CSR(pl022->virtbase));
450}
451
452static void pl022_cs_control(struct pl022 *pl022, u32 command)
453{
454 if (pl022->vendor->internal_cs_ctrl)
455 internal_cs_control(pl022, command);
456 else if (pl022->cur_gpiod)
457 /*
458 * This needs to be inverted since with GPIOLIB in
459 * control, the inversion will be handled by
460 * GPIOLIB's active low handling. The "command"
461 * passed into this function will be SSP_CHIP_SELECT
462 * which is enum:ed to 0, so we need the inverse
463 * (1) to activate chip select.
464 */
465 gpiod_set_value(pl022->cur_gpiod, !command);
466}
467
468/**
469 * giveback - current spi_message is over, schedule next message and call
470 * callback of this message. Assumes that caller already
471 * set message->status; dma and pio irqs are blocked
472 * @pl022: SSP driver private data structure
473 */
474static void giveback(struct pl022 *pl022)
475{
476 struct spi_transfer *last_transfer;
477 pl022->next_msg_cs_active = false;
478
479 last_transfer = list_last_entry(&pl022->cur_msg->transfers,
480 struct spi_transfer, transfer_list);
481
482 /* Delay if requested before any change in chip select */
483 /*
484 * FIXME: This runs in interrupt context.
485 * Is this really smart?
486 */
487 spi_transfer_delay_exec(last_transfer);
488
489 if (!last_transfer->cs_change) {
490 struct spi_message *next_msg;
491
492 /*
493 * cs_change was not set. We can keep the chip select
494 * enabled if there is message in the queue and it is
495 * for the same spi device.
496 *
497 * We cannot postpone this until pump_messages, because
498 * after calling msg->complete (below) the driver that
499 * sent the current message could be unloaded, which
500 * could invalidate the cs_control() callback...
501 */
502 /* get a pointer to the next message, if any */
503 next_msg = spi_get_next_queued_message(pl022->master);
504
505 /*
506 * see if the next and current messages point
507 * to the same spi device.
508 */
509 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
510 next_msg = NULL;
511 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
512 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
513 else
514 pl022->next_msg_cs_active = true;
515
516 }
517
518 pl022->cur_msg = NULL;
519 pl022->cur_transfer = NULL;
520 pl022->cur_chip = NULL;
521
522 /* disable the SPI/SSP operation */
523 writew((readw(SSP_CR1(pl022->virtbase)) &
524 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
525
526 spi_finalize_current_message(pl022->master);
527}
528
529/**
530 * flush - flush the FIFO to reach a clean state
531 * @pl022: SSP driver private data structure
532 */
533static int flush(struct pl022 *pl022)
534{
535 unsigned long limit = loops_per_jiffy << 1;
536
537 dev_dbg(&pl022->adev->dev, "flush\n");
538 do {
539 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
540 readw(SSP_DR(pl022->virtbase));
541 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
542
543 pl022->exp_fifo_level = 0;
544
545 return limit;
546}
547
548/**
549 * restore_state - Load configuration of current chip
550 * @pl022: SSP driver private data structure
551 */
552static void restore_state(struct pl022 *pl022)
553{
554 struct chip_data *chip = pl022->cur_chip;
555
556 if (pl022->vendor->extended_cr)
557 writel(chip->cr0, SSP_CR0(pl022->virtbase));
558 else
559 writew(chip->cr0, SSP_CR0(pl022->virtbase));
560 writew(chip->cr1, SSP_CR1(pl022->virtbase));
561 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
562 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
563 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
564 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
565}
566
567/*
568 * Default SSP Register Values
569 */
570#define DEFAULT_SSP_REG_CR0 ( \
571 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
572 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
573 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
574 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
575 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
576)
577
578/* ST versions have slightly different bit layout */
579#define DEFAULT_SSP_REG_CR0_ST ( \
580 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
581 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
582 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
583 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
584 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
585 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
586 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
587)
588
589/* The PL023 version is slightly different again */
590#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
591 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
592 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
593 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
594 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
595)
596
597#define DEFAULT_SSP_REG_CR1 ( \
598 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
599 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
600 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
601 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
602)
603
604/* ST versions extend this register to use all 16 bits */
605#define DEFAULT_SSP_REG_CR1_ST ( \
606 DEFAULT_SSP_REG_CR1 | \
607 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
608 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
609 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
610 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
611 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
612)
613
614/*
615 * The PL023 variant has further differences: no loopback mode, no microwire
616 * support, and a new clock feedback delay setting.
617 */
618#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
619 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
620 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
621 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
622 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
623 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
624 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
625 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
626 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
627)
628
629#define DEFAULT_SSP_REG_CPSR ( \
630 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
631)
632
633#define DEFAULT_SSP_REG_DMACR (\
634 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
635 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
636)
637
638/**
639 * load_ssp_default_config - Load default configuration for SSP
640 * @pl022: SSP driver private data structure
641 */
642static void load_ssp_default_config(struct pl022 *pl022)
643{
644 if (pl022->vendor->pl023) {
645 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
646 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
647 } else if (pl022->vendor->extended_cr) {
648 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
649 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
650 } else {
651 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
652 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
653 }
654 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
655 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
656 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
657 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
658}
659
660/*
661 * This will write to TX and read from RX according to the parameters
662 * set in pl022.
663 */
664static void readwriter(struct pl022 *pl022)
665{
666
667 /*
668 * The FIFO depth is different between primecell variants.
669 * I believe filling in too much in the FIFO might cause
670 * errons in 8bit wide transfers on ARM variants (just 8 words
671 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
672 *
673 * To prevent this issue, the TX FIFO is only filled to the
674 * unused RX FIFO fill length, regardless of what the TX
675 * FIFO status flag indicates.
676 */
677 dev_dbg(&pl022->adev->dev,
678 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
679 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
680
681 /* Read as much as you can */
682 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
683 && (pl022->rx < pl022->rx_end)) {
684 switch (pl022->read) {
685 case READING_NULL:
686 readw(SSP_DR(pl022->virtbase));
687 break;
688 case READING_U8:
689 *(u8 *) (pl022->rx) =
690 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
691 break;
692 case READING_U16:
693 *(u16 *) (pl022->rx) =
694 (u16) readw(SSP_DR(pl022->virtbase));
695 break;
696 case READING_U32:
697 *(u32 *) (pl022->rx) =
698 readl(SSP_DR(pl022->virtbase));
699 break;
700 }
701 pl022->rx += (pl022->cur_chip->n_bytes);
702 pl022->exp_fifo_level--;
703 }
704 /*
705 * Write as much as possible up to the RX FIFO size
706 */
707 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
708 && (pl022->tx < pl022->tx_end)) {
709 switch (pl022->write) {
710 case WRITING_NULL:
711 writew(0x0, SSP_DR(pl022->virtbase));
712 break;
713 case WRITING_U8:
714 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
715 break;
716 case WRITING_U16:
717 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
718 break;
719 case WRITING_U32:
720 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
721 break;
722 }
723 pl022->tx += (pl022->cur_chip->n_bytes);
724 pl022->exp_fifo_level++;
725 /*
726 * This inner reader takes care of things appearing in the RX
727 * FIFO as we're transmitting. This will happen a lot since the
728 * clock starts running when you put things into the TX FIFO,
729 * and then things are continuously clocked into the RX FIFO.
730 */
731 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
732 && (pl022->rx < pl022->rx_end)) {
733 switch (pl022->read) {
734 case READING_NULL:
735 readw(SSP_DR(pl022->virtbase));
736 break;
737 case READING_U8:
738 *(u8 *) (pl022->rx) =
739 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
740 break;
741 case READING_U16:
742 *(u16 *) (pl022->rx) =
743 (u16) readw(SSP_DR(pl022->virtbase));
744 break;
745 case READING_U32:
746 *(u32 *) (pl022->rx) =
747 readl(SSP_DR(pl022->virtbase));
748 break;
749 }
750 pl022->rx += (pl022->cur_chip->n_bytes);
751 pl022->exp_fifo_level--;
752 }
753 }
754 /*
755 * When we exit here the TX FIFO should be full and the RX FIFO
756 * should be empty
757 */
758}
759
760/**
761 * next_transfer - Move to the Next transfer in the current spi message
762 * @pl022: SSP driver private data structure
763 *
764 * This function moves though the linked list of spi transfers in the
765 * current spi message and returns with the state of current spi
766 * message i.e whether its last transfer is done(STATE_DONE) or
767 * Next transfer is ready(STATE_RUNNING)
768 */
769static void *next_transfer(struct pl022 *pl022)
770{
771 struct spi_message *msg = pl022->cur_msg;
772 struct spi_transfer *trans = pl022->cur_transfer;
773
774 /* Move to next transfer */
775 if (trans->transfer_list.next != &msg->transfers) {
776 pl022->cur_transfer =
777 list_entry(trans->transfer_list.next,
778 struct spi_transfer, transfer_list);
779 return STATE_RUNNING;
780 }
781 return STATE_DONE;
782}
783
784/*
785 * This DMA functionality is only compiled in if we have
786 * access to the generic DMA devices/DMA engine.
787 */
788#ifdef CONFIG_DMA_ENGINE
789static void unmap_free_dma_scatter(struct pl022 *pl022)
790{
791 /* Unmap and free the SG tables */
792 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
793 pl022->sgt_tx.nents, DMA_TO_DEVICE);
794 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
795 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
796 sg_free_table(&pl022->sgt_rx);
797 sg_free_table(&pl022->sgt_tx);
798}
799
800static void dma_callback(void *data)
801{
802 struct pl022 *pl022 = data;
803 struct spi_message *msg = pl022->cur_msg;
804
805 BUG_ON(!pl022->sgt_rx.sgl);
806
807#ifdef VERBOSE_DEBUG
808 /*
809 * Optionally dump out buffers to inspect contents, this is
810 * good if you want to convince yourself that the loopback
811 * read/write contents are the same, when adopting to a new
812 * DMA engine.
813 */
814 {
815 struct scatterlist *sg;
816 unsigned int i;
817
818 dma_sync_sg_for_cpu(&pl022->adev->dev,
819 pl022->sgt_rx.sgl,
820 pl022->sgt_rx.nents,
821 DMA_FROM_DEVICE);
822
823 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
824 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
825 print_hex_dump(KERN_ERR, "SPI RX: ",
826 DUMP_PREFIX_OFFSET,
827 16,
828 1,
829 sg_virt(sg),
830 sg_dma_len(sg),
831 1);
832 }
833 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
834 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
835 print_hex_dump(KERN_ERR, "SPI TX: ",
836 DUMP_PREFIX_OFFSET,
837 16,
838 1,
839 sg_virt(sg),
840 sg_dma_len(sg),
841 1);
842 }
843 }
844#endif
845
846 unmap_free_dma_scatter(pl022);
847
848 /* Update total bytes transferred */
849 msg->actual_length += pl022->cur_transfer->len;
850 /* Move to next transfer */
851 msg->state = next_transfer(pl022);
852 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
853 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
854 tasklet_schedule(&pl022->pump_transfers);
855}
856
857static void setup_dma_scatter(struct pl022 *pl022,
858 void *buffer,
859 unsigned int length,
860 struct sg_table *sgtab)
861{
862 struct scatterlist *sg;
863 int bytesleft = length;
864 void *bufp = buffer;
865 int mapbytes;
866 int i;
867
868 if (buffer) {
869 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
870 /*
871 * If there are less bytes left than what fits
872 * in the current page (plus page alignment offset)
873 * we just feed in this, else we stuff in as much
874 * as we can.
875 */
876 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
877 mapbytes = bytesleft;
878 else
879 mapbytes = PAGE_SIZE - offset_in_page(bufp);
880 sg_set_page(sg, virt_to_page(bufp),
881 mapbytes, offset_in_page(bufp));
882 bufp += mapbytes;
883 bytesleft -= mapbytes;
884 dev_dbg(&pl022->adev->dev,
885 "set RX/TX target page @ %p, %d bytes, %d left\n",
886 bufp, mapbytes, bytesleft);
887 }
888 } else {
889 /* Map the dummy buffer on every page */
890 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
891 if (bytesleft < PAGE_SIZE)
892 mapbytes = bytesleft;
893 else
894 mapbytes = PAGE_SIZE;
895 sg_set_page(sg, virt_to_page(pl022->dummypage),
896 mapbytes, 0);
897 bytesleft -= mapbytes;
898 dev_dbg(&pl022->adev->dev,
899 "set RX/TX to dummy page %d bytes, %d left\n",
900 mapbytes, bytesleft);
901
902 }
903 }
904 BUG_ON(bytesleft);
905}
906
907/**
908 * configure_dma - configures the channels for the next transfer
909 * @pl022: SSP driver's private data structure
910 */
911static int configure_dma(struct pl022 *pl022)
912{
913 struct dma_slave_config rx_conf = {
914 .src_addr = SSP_DR(pl022->phybase),
915 .direction = DMA_DEV_TO_MEM,
916 .device_fc = false,
917 };
918 struct dma_slave_config tx_conf = {
919 .dst_addr = SSP_DR(pl022->phybase),
920 .direction = DMA_MEM_TO_DEV,
921 .device_fc = false,
922 };
923 unsigned int pages;
924 int ret;
925 int rx_sglen, tx_sglen;
926 struct dma_chan *rxchan = pl022->dma_rx_channel;
927 struct dma_chan *txchan = pl022->dma_tx_channel;
928 struct dma_async_tx_descriptor *rxdesc;
929 struct dma_async_tx_descriptor *txdesc;
930
931 /* Check that the channels are available */
932 if (!rxchan || !txchan)
933 return -ENODEV;
934
935 /*
936 * If supplied, the DMA burstsize should equal the FIFO trigger level.
937 * Notice that the DMA engine uses one-to-one mapping. Since we can
938 * not trigger on 2 elements this needs explicit mapping rather than
939 * calculation.
940 */
941 switch (pl022->rx_lev_trig) {
942 case SSP_RX_1_OR_MORE_ELEM:
943 rx_conf.src_maxburst = 1;
944 break;
945 case SSP_RX_4_OR_MORE_ELEM:
946 rx_conf.src_maxburst = 4;
947 break;
948 case SSP_RX_8_OR_MORE_ELEM:
949 rx_conf.src_maxburst = 8;
950 break;
951 case SSP_RX_16_OR_MORE_ELEM:
952 rx_conf.src_maxburst = 16;
953 break;
954 case SSP_RX_32_OR_MORE_ELEM:
955 rx_conf.src_maxburst = 32;
956 break;
957 default:
958 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
959 break;
960 }
961
962 switch (pl022->tx_lev_trig) {
963 case SSP_TX_1_OR_MORE_EMPTY_LOC:
964 tx_conf.dst_maxburst = 1;
965 break;
966 case SSP_TX_4_OR_MORE_EMPTY_LOC:
967 tx_conf.dst_maxburst = 4;
968 break;
969 case SSP_TX_8_OR_MORE_EMPTY_LOC:
970 tx_conf.dst_maxburst = 8;
971 break;
972 case SSP_TX_16_OR_MORE_EMPTY_LOC:
973 tx_conf.dst_maxburst = 16;
974 break;
975 case SSP_TX_32_OR_MORE_EMPTY_LOC:
976 tx_conf.dst_maxburst = 32;
977 break;
978 default:
979 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
980 break;
981 }
982
983 switch (pl022->read) {
984 case READING_NULL:
985 /* Use the same as for writing */
986 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
987 break;
988 case READING_U8:
989 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
990 break;
991 case READING_U16:
992 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
993 break;
994 case READING_U32:
995 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
996 break;
997 }
998
999 switch (pl022->write) {
1000 case WRITING_NULL:
1001 /* Use the same as for reading */
1002 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1003 break;
1004 case WRITING_U8:
1005 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1006 break;
1007 case WRITING_U16:
1008 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1009 break;
1010 case WRITING_U32:
1011 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1012 break;
1013 }
1014
1015 /* SPI pecularity: we need to read and write the same width */
1016 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1017 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1018 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1019 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1020 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1021
1022 dmaengine_slave_config(rxchan, &rx_conf);
1023 dmaengine_slave_config(txchan, &tx_conf);
1024
1025 /* Create sglists for the transfers */
1026 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1027 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1028
1029 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1030 if (ret)
1031 goto err_alloc_rx_sg;
1032
1033 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1034 if (ret)
1035 goto err_alloc_tx_sg;
1036
1037 /* Fill in the scatterlists for the RX+TX buffers */
1038 setup_dma_scatter(pl022, pl022->rx,
1039 pl022->cur_transfer->len, &pl022->sgt_rx);
1040 setup_dma_scatter(pl022, pl022->tx,
1041 pl022->cur_transfer->len, &pl022->sgt_tx);
1042
1043 /* Map DMA buffers */
1044 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1045 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1046 if (!rx_sglen)
1047 goto err_rx_sgmap;
1048
1049 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1050 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1051 if (!tx_sglen)
1052 goto err_tx_sgmap;
1053
1054 /* Send both scatterlists */
1055 rxdesc = dmaengine_prep_slave_sg(rxchan,
1056 pl022->sgt_rx.sgl,
1057 rx_sglen,
1058 DMA_DEV_TO_MEM,
1059 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1060 if (!rxdesc)
1061 goto err_rxdesc;
1062
1063 txdesc = dmaengine_prep_slave_sg(txchan,
1064 pl022->sgt_tx.sgl,
1065 tx_sglen,
1066 DMA_MEM_TO_DEV,
1067 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1068 if (!txdesc)
1069 goto err_txdesc;
1070
1071 /* Put the callback on the RX transfer only, that should finish last */
1072 rxdesc->callback = dma_callback;
1073 rxdesc->callback_param = pl022;
1074
1075 /* Submit and fire RX and TX with TX last so we're ready to read! */
1076 dmaengine_submit(rxdesc);
1077 dmaengine_submit(txdesc);
1078 dma_async_issue_pending(rxchan);
1079 dma_async_issue_pending(txchan);
1080 pl022->dma_running = true;
1081
1082 return 0;
1083
1084err_txdesc:
1085 dmaengine_terminate_all(txchan);
1086err_rxdesc:
1087 dmaengine_terminate_all(rxchan);
1088 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1089 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1090err_tx_sgmap:
1091 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1092 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1093err_rx_sgmap:
1094 sg_free_table(&pl022->sgt_tx);
1095err_alloc_tx_sg:
1096 sg_free_table(&pl022->sgt_rx);
1097err_alloc_rx_sg:
1098 return -ENOMEM;
1099}
1100
1101static int pl022_dma_probe(struct pl022 *pl022)
1102{
1103 dma_cap_mask_t mask;
1104
1105 /* Try to acquire a generic DMA engine slave channel */
1106 dma_cap_zero(mask);
1107 dma_cap_set(DMA_SLAVE, mask);
1108 /*
1109 * We need both RX and TX channels to do DMA, else do none
1110 * of them.
1111 */
1112 pl022->dma_rx_channel = dma_request_channel(mask,
1113 pl022->master_info->dma_filter,
1114 pl022->master_info->dma_rx_param);
1115 if (!pl022->dma_rx_channel) {
1116 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1117 goto err_no_rxchan;
1118 }
1119
1120 pl022->dma_tx_channel = dma_request_channel(mask,
1121 pl022->master_info->dma_filter,
1122 pl022->master_info->dma_tx_param);
1123 if (!pl022->dma_tx_channel) {
1124 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1125 goto err_no_txchan;
1126 }
1127
1128 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1129 if (!pl022->dummypage)
1130 goto err_no_dummypage;
1131
1132 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1133 dma_chan_name(pl022->dma_rx_channel),
1134 dma_chan_name(pl022->dma_tx_channel));
1135
1136 return 0;
1137
1138err_no_dummypage:
1139 dma_release_channel(pl022->dma_tx_channel);
1140err_no_txchan:
1141 dma_release_channel(pl022->dma_rx_channel);
1142 pl022->dma_rx_channel = NULL;
1143err_no_rxchan:
1144 dev_err(&pl022->adev->dev,
1145 "Failed to work in dma mode, work without dma!\n");
1146 return -ENODEV;
1147}
1148
1149static int pl022_dma_autoprobe(struct pl022 *pl022)
1150{
1151 struct device *dev = &pl022->adev->dev;
1152 struct dma_chan *chan;
1153 int err;
1154
1155 /* automatically configure DMA channels from platform, normally using DT */
1156 chan = dma_request_chan(dev, "rx");
1157 if (IS_ERR(chan)) {
1158 err = PTR_ERR(chan);
1159 goto err_no_rxchan;
1160 }
1161
1162 pl022->dma_rx_channel = chan;
1163
1164 chan = dma_request_chan(dev, "tx");
1165 if (IS_ERR(chan)) {
1166 err = PTR_ERR(chan);
1167 goto err_no_txchan;
1168 }
1169
1170 pl022->dma_tx_channel = chan;
1171
1172 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1173 if (!pl022->dummypage) {
1174 err = -ENOMEM;
1175 goto err_no_dummypage;
1176 }
1177
1178 return 0;
1179
1180err_no_dummypage:
1181 dma_release_channel(pl022->dma_tx_channel);
1182 pl022->dma_tx_channel = NULL;
1183err_no_txchan:
1184 dma_release_channel(pl022->dma_rx_channel);
1185 pl022->dma_rx_channel = NULL;
1186err_no_rxchan:
1187 return err;
1188}
1189
1190static void terminate_dma(struct pl022 *pl022)
1191{
1192 struct dma_chan *rxchan = pl022->dma_rx_channel;
1193 struct dma_chan *txchan = pl022->dma_tx_channel;
1194
1195 dmaengine_terminate_all(rxchan);
1196 dmaengine_terminate_all(txchan);
1197 unmap_free_dma_scatter(pl022);
1198 pl022->dma_running = false;
1199}
1200
1201static void pl022_dma_remove(struct pl022 *pl022)
1202{
1203 if (pl022->dma_running)
1204 terminate_dma(pl022);
1205 if (pl022->dma_tx_channel)
1206 dma_release_channel(pl022->dma_tx_channel);
1207 if (pl022->dma_rx_channel)
1208 dma_release_channel(pl022->dma_rx_channel);
1209 kfree(pl022->dummypage);
1210}
1211
1212#else
1213static inline int configure_dma(struct pl022 *pl022)
1214{
1215 return -ENODEV;
1216}
1217
1218static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1219{
1220 return 0;
1221}
1222
1223static inline int pl022_dma_probe(struct pl022 *pl022)
1224{
1225 return 0;
1226}
1227
1228static inline void pl022_dma_remove(struct pl022 *pl022)
1229{
1230}
1231#endif
1232
1233/**
1234 * pl022_interrupt_handler - Interrupt handler for SSP controller
1235 * @irq: IRQ number
1236 * @dev_id: Local device data
1237 *
1238 * This function handles interrupts generated for an interrupt based transfer.
1239 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1240 * current message's state as STATE_ERROR and schedule the tasklet
1241 * pump_transfers which will do the postprocessing of the current message by
1242 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1243 * more data, and writes data in TX FIFO till it is not full. If we complete
1244 * the transfer we move to the next transfer and schedule the tasklet.
1245 */
1246static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1247{
1248 struct pl022 *pl022 = dev_id;
1249 struct spi_message *msg = pl022->cur_msg;
1250 u16 irq_status = 0;
1251
1252 if (unlikely(!msg)) {
1253 dev_err(&pl022->adev->dev,
1254 "bad message state in interrupt handler");
1255 /* Never fail */
1256 return IRQ_HANDLED;
1257 }
1258
1259 /* Read the Interrupt Status Register */
1260 irq_status = readw(SSP_MIS(pl022->virtbase));
1261
1262 if (unlikely(!irq_status))
1263 return IRQ_NONE;
1264
1265 /*
1266 * This handles the FIFO interrupts, the timeout
1267 * interrupts are flatly ignored, they cannot be
1268 * trusted.
1269 */
1270 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1271 /*
1272 * Overrun interrupt - bail out since our Data has been
1273 * corrupted
1274 */
1275 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1276 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1277 dev_err(&pl022->adev->dev,
1278 "RXFIFO is full\n");
1279
1280 /*
1281 * Disable and clear interrupts, disable SSP,
1282 * mark message with bad status so it can be
1283 * retried.
1284 */
1285 writew(DISABLE_ALL_INTERRUPTS,
1286 SSP_IMSC(pl022->virtbase));
1287 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1288 writew((readw(SSP_CR1(pl022->virtbase)) &
1289 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1290 msg->state = STATE_ERROR;
1291
1292 /* Schedule message queue handler */
1293 tasklet_schedule(&pl022->pump_transfers);
1294 return IRQ_HANDLED;
1295 }
1296
1297 readwriter(pl022);
1298
1299 if (pl022->tx == pl022->tx_end) {
1300 /* Disable Transmit interrupt, enable receive interrupt */
1301 writew((readw(SSP_IMSC(pl022->virtbase)) &
1302 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1303 SSP_IMSC(pl022->virtbase));
1304 }
1305
1306 /*
1307 * Since all transactions must write as much as shall be read,
1308 * we can conclude the entire transaction once RX is complete.
1309 * At this point, all TX will always be finished.
1310 */
1311 if (pl022->rx >= pl022->rx_end) {
1312 writew(DISABLE_ALL_INTERRUPTS,
1313 SSP_IMSC(pl022->virtbase));
1314 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1315 if (unlikely(pl022->rx > pl022->rx_end)) {
1316 dev_warn(&pl022->adev->dev, "read %u surplus "
1317 "bytes (did you request an odd "
1318 "number of bytes on a 16bit bus?)\n",
1319 (u32) (pl022->rx - pl022->rx_end));
1320 }
1321 /* Update total bytes transferred */
1322 msg->actual_length += pl022->cur_transfer->len;
1323 /* Move to next transfer */
1324 msg->state = next_transfer(pl022);
1325 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
1326 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1327 tasklet_schedule(&pl022->pump_transfers);
1328 return IRQ_HANDLED;
1329 }
1330
1331 return IRQ_HANDLED;
1332}
1333
1334/*
1335 * This sets up the pointers to memory for the next message to
1336 * send out on the SPI bus.
1337 */
1338static int set_up_next_transfer(struct pl022 *pl022,
1339 struct spi_transfer *transfer)
1340{
1341 int residue;
1342
1343 /* Sanity check the message for this bus width */
1344 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1345 if (unlikely(residue != 0)) {
1346 dev_err(&pl022->adev->dev,
1347 "message of %u bytes to transmit but the current "
1348 "chip bus has a data width of %u bytes!\n",
1349 pl022->cur_transfer->len,
1350 pl022->cur_chip->n_bytes);
1351 dev_err(&pl022->adev->dev, "skipping this message\n");
1352 return -EIO;
1353 }
1354 pl022->tx = (void *)transfer->tx_buf;
1355 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1356 pl022->rx = (void *)transfer->rx_buf;
1357 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1358 pl022->write =
1359 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1360 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1361 return 0;
1362}
1363
1364/**
1365 * pump_transfers - Tasklet function which schedules next transfer
1366 * when running in interrupt or DMA transfer mode.
1367 * @data: SSP driver private data structure
1368 *
1369 */
1370static void pump_transfers(unsigned long data)
1371{
1372 struct pl022 *pl022 = (struct pl022 *) data;
1373 struct spi_message *message = NULL;
1374 struct spi_transfer *transfer = NULL;
1375 struct spi_transfer *previous = NULL;
1376
1377 /* Get current state information */
1378 message = pl022->cur_msg;
1379 transfer = pl022->cur_transfer;
1380
1381 /* Handle for abort */
1382 if (message->state == STATE_ERROR) {
1383 message->status = -EIO;
1384 giveback(pl022);
1385 return;
1386 }
1387
1388 /* Handle end of message */
1389 if (message->state == STATE_DONE) {
1390 message->status = 0;
1391 giveback(pl022);
1392 return;
1393 }
1394
1395 /* Delay if requested at end of transfer before CS change */
1396 if (message->state == STATE_RUNNING) {
1397 previous = list_entry(transfer->transfer_list.prev,
1398 struct spi_transfer,
1399 transfer_list);
1400 /*
1401 * FIXME: This runs in interrupt context.
1402 * Is this really smart?
1403 */
1404 spi_transfer_delay_exec(previous);
1405
1406 /* Reselect chip select only if cs_change was requested */
1407 if (previous->cs_change)
1408 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1409 } else {
1410 /* STATE_START */
1411 message->state = STATE_RUNNING;
1412 }
1413
1414 if (set_up_next_transfer(pl022, transfer)) {
1415 message->state = STATE_ERROR;
1416 message->status = -EIO;
1417 giveback(pl022);
1418 return;
1419 }
1420 /* Flush the FIFOs and let's go! */
1421 flush(pl022);
1422
1423 if (pl022->cur_chip->enable_dma) {
1424 if (configure_dma(pl022)) {
1425 dev_dbg(&pl022->adev->dev,
1426 "configuration of DMA failed, fall back to interrupt mode\n");
1427 goto err_config_dma;
1428 }
1429 return;
1430 }
1431
1432err_config_dma:
1433 /* enable all interrupts except RX */
1434 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1435}
1436
1437static void do_interrupt_dma_transfer(struct pl022 *pl022)
1438{
1439 /*
1440 * Default is to enable all interrupts except RX -
1441 * this will be enabled once TX is complete
1442 */
1443 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1444
1445 /* Enable target chip, if not already active */
1446 if (!pl022->next_msg_cs_active)
1447 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1448
1449 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1450 /* Error path */
1451 pl022->cur_msg->state = STATE_ERROR;
1452 pl022->cur_msg->status = -EIO;
1453 giveback(pl022);
1454 return;
1455 }
1456 /* If we're using DMA, set up DMA here */
1457 if (pl022->cur_chip->enable_dma) {
1458 /* Configure DMA transfer */
1459 if (configure_dma(pl022)) {
1460 dev_dbg(&pl022->adev->dev,
1461 "configuration of DMA failed, fall back to interrupt mode\n");
1462 goto err_config_dma;
1463 }
1464 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1465 irqflags = DISABLE_ALL_INTERRUPTS;
1466 }
1467err_config_dma:
1468 /* Enable SSP, turn on interrupts */
1469 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1470 SSP_CR1(pl022->virtbase));
1471 writew(irqflags, SSP_IMSC(pl022->virtbase));
1472}
1473
1474static void print_current_status(struct pl022 *pl022)
1475{
1476 u32 read_cr0;
1477 u16 read_cr1, read_dmacr, read_sr;
1478
1479 if (pl022->vendor->extended_cr)
1480 read_cr0 = readl(SSP_CR0(pl022->virtbase));
1481 else
1482 read_cr0 = readw(SSP_CR0(pl022->virtbase));
1483 read_cr1 = readw(SSP_CR1(pl022->virtbase));
1484 read_dmacr = readw(SSP_DMACR(pl022->virtbase));
1485 read_sr = readw(SSP_SR(pl022->virtbase));
1486
1487 dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
1488 dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
1489 dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
1490 dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
1491 dev_warn(&pl022->adev->dev,
1492 "spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
1493 pl022->exp_fifo_level,
1494 pl022->vendor->fifodepth);
1495
1496}
1497
1498static void do_polling_transfer(struct pl022 *pl022)
1499{
1500 struct spi_message *message = NULL;
1501 struct spi_transfer *transfer = NULL;
1502 struct spi_transfer *previous = NULL;
1503 unsigned long time, timeout;
1504
1505 message = pl022->cur_msg;
1506
1507 while (message->state != STATE_DONE) {
1508 /* Handle for abort */
1509 if (message->state == STATE_ERROR)
1510 break;
1511 transfer = pl022->cur_transfer;
1512
1513 /* Delay if requested at end of transfer */
1514 if (message->state == STATE_RUNNING) {
1515 previous =
1516 list_entry(transfer->transfer_list.prev,
1517 struct spi_transfer, transfer_list);
1518 spi_transfer_delay_exec(previous);
1519 if (previous->cs_change)
1520 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1521 } else {
1522 /* STATE_START */
1523 message->state = STATE_RUNNING;
1524 if (!pl022->next_msg_cs_active)
1525 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1526 }
1527
1528 /* Configuration Changing Per Transfer */
1529 if (set_up_next_transfer(pl022, transfer)) {
1530 /* Error path */
1531 message->state = STATE_ERROR;
1532 break;
1533 }
1534 /* Flush FIFOs and enable SSP */
1535 flush(pl022);
1536 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1537 SSP_CR1(pl022->virtbase));
1538
1539 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1540
1541 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1542 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1543 time = jiffies;
1544 readwriter(pl022);
1545 if (time_after(time, timeout)) {
1546 dev_warn(&pl022->adev->dev,
1547 "%s: timeout!\n", __func__);
1548 message->state = STATE_TIMEOUT;
1549 print_current_status(pl022);
1550 goto out;
1551 }
1552 cpu_relax();
1553 }
1554
1555 /* Update total byte transferred */
1556 message->actual_length += pl022->cur_transfer->len;
1557 /* Move to next transfer */
1558 message->state = next_transfer(pl022);
1559 if (message->state != STATE_DONE
1560 && pl022->cur_transfer->cs_change)
1561 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1562 }
1563out:
1564 /* Handle end of message */
1565 if (message->state == STATE_DONE)
1566 message->status = 0;
1567 else if (message->state == STATE_TIMEOUT)
1568 message->status = -EAGAIN;
1569 else
1570 message->status = -EIO;
1571
1572 giveback(pl022);
1573 return;
1574}
1575
1576static int pl022_transfer_one_message(struct spi_master *master,
1577 struct spi_message *msg)
1578{
1579 struct pl022 *pl022 = spi_master_get_devdata(master);
1580
1581 /* Initial message state */
1582 pl022->cur_msg = msg;
1583 msg->state = STATE_START;
1584
1585 pl022->cur_transfer = list_entry(msg->transfers.next,
1586 struct spi_transfer, transfer_list);
1587
1588 /* Setup the SPI using the per chip configuration */
1589 pl022->cur_chip = spi_get_ctldata(msg->spi);
1590 pl022->cur_cs = msg->spi->chip_select;
1591 /* This is always available but may be set to -ENOENT */
1592 pl022->cur_gpiod = msg->spi->cs_gpiod;
1593
1594 restore_state(pl022);
1595 flush(pl022);
1596
1597 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1598 do_polling_transfer(pl022);
1599 else
1600 do_interrupt_dma_transfer(pl022);
1601
1602 return 0;
1603}
1604
1605static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1606{
1607 struct pl022 *pl022 = spi_master_get_devdata(master);
1608
1609 /* nothing more to do - disable spi/ssp and power off */
1610 writew((readw(SSP_CR1(pl022->virtbase)) &
1611 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1612
1613 return 0;
1614}
1615
1616static int verify_controller_parameters(struct pl022 *pl022,
1617 struct pl022_config_chip const *chip_info)
1618{
1619 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1620 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1621 dev_err(&pl022->adev->dev,
1622 "interface is configured incorrectly\n");
1623 return -EINVAL;
1624 }
1625 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1626 (!pl022->vendor->unidir)) {
1627 dev_err(&pl022->adev->dev,
1628 "unidirectional mode not supported in this "
1629 "hardware version\n");
1630 return -EINVAL;
1631 }
1632 if ((chip_info->hierarchy != SSP_MASTER)
1633 && (chip_info->hierarchy != SSP_SLAVE)) {
1634 dev_err(&pl022->adev->dev,
1635 "hierarchy is configured incorrectly\n");
1636 return -EINVAL;
1637 }
1638 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1639 && (chip_info->com_mode != DMA_TRANSFER)
1640 && (chip_info->com_mode != POLLING_TRANSFER)) {
1641 dev_err(&pl022->adev->dev,
1642 "Communication mode is configured incorrectly\n");
1643 return -EINVAL;
1644 }
1645 switch (chip_info->rx_lev_trig) {
1646 case SSP_RX_1_OR_MORE_ELEM:
1647 case SSP_RX_4_OR_MORE_ELEM:
1648 case SSP_RX_8_OR_MORE_ELEM:
1649 /* These are always OK, all variants can handle this */
1650 break;
1651 case SSP_RX_16_OR_MORE_ELEM:
1652 if (pl022->vendor->fifodepth < 16) {
1653 dev_err(&pl022->adev->dev,
1654 "RX FIFO Trigger Level is configured incorrectly\n");
1655 return -EINVAL;
1656 }
1657 break;
1658 case SSP_RX_32_OR_MORE_ELEM:
1659 if (pl022->vendor->fifodepth < 32) {
1660 dev_err(&pl022->adev->dev,
1661 "RX FIFO Trigger Level is configured incorrectly\n");
1662 return -EINVAL;
1663 }
1664 break;
1665 default:
1666 dev_err(&pl022->adev->dev,
1667 "RX FIFO Trigger Level is configured incorrectly\n");
1668 return -EINVAL;
1669 }
1670 switch (chip_info->tx_lev_trig) {
1671 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1672 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1673 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1674 /* These are always OK, all variants can handle this */
1675 break;
1676 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1677 if (pl022->vendor->fifodepth < 16) {
1678 dev_err(&pl022->adev->dev,
1679 "TX FIFO Trigger Level is configured incorrectly\n");
1680 return -EINVAL;
1681 }
1682 break;
1683 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1684 if (pl022->vendor->fifodepth < 32) {
1685 dev_err(&pl022->adev->dev,
1686 "TX FIFO Trigger Level is configured incorrectly\n");
1687 return -EINVAL;
1688 }
1689 break;
1690 default:
1691 dev_err(&pl022->adev->dev,
1692 "TX FIFO Trigger Level is configured incorrectly\n");
1693 return -EINVAL;
1694 }
1695 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1696 if ((chip_info->ctrl_len < SSP_BITS_4)
1697 || (chip_info->ctrl_len > SSP_BITS_32)) {
1698 dev_err(&pl022->adev->dev,
1699 "CTRL LEN is configured incorrectly\n");
1700 return -EINVAL;
1701 }
1702 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1703 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1704 dev_err(&pl022->adev->dev,
1705 "Wait State is configured incorrectly\n");
1706 return -EINVAL;
1707 }
1708 /* Half duplex is only available in the ST Micro version */
1709 if (pl022->vendor->extended_cr) {
1710 if ((chip_info->duplex !=
1711 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1712 && (chip_info->duplex !=
1713 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1714 dev_err(&pl022->adev->dev,
1715 "Microwire duplex mode is configured incorrectly\n");
1716 return -EINVAL;
1717 }
1718 } else {
1719 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) {
1720 dev_err(&pl022->adev->dev,
1721 "Microwire half duplex mode requested,"
1722 " but this is only available in the"
1723 " ST version of PL022\n");
1724 return -EINVAL;
1725 }
1726 }
1727 }
1728 return 0;
1729}
1730
1731static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1732{
1733 return rate / (cpsdvsr * (1 + scr));
1734}
1735
1736static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1737 ssp_clock_params * clk_freq)
1738{
1739 /* Lets calculate the frequency parameters */
1740 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1741 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1742 best_scr = 0, tmp, found = 0;
1743
1744 rate = clk_get_rate(pl022->clk);
1745 /* cpsdvscr = 2 & scr 0 */
1746 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1747 /* cpsdvsr = 254 & scr = 255 */
1748 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1749
1750 if (freq > max_tclk)
1751 dev_warn(&pl022->adev->dev,
1752 "Max speed that can be programmed is %d Hz, you requested %d\n",
1753 max_tclk, freq);
1754
1755 if (freq < min_tclk) {
1756 dev_err(&pl022->adev->dev,
1757 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1758 freq, min_tclk);
1759 return -EINVAL;
1760 }
1761
1762 /*
1763 * best_freq will give closest possible available rate (<= requested
1764 * freq) for all values of scr & cpsdvsr.
1765 */
1766 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1767 while (scr <= SCR_MAX) {
1768 tmp = spi_rate(rate, cpsdvsr, scr);
1769
1770 if (tmp > freq) {
1771 /* we need lower freq */
1772 scr++;
1773 continue;
1774 }
1775
1776 /*
1777 * If found exact value, mark found and break.
1778 * If found more closer value, update and break.
1779 */
1780 if (tmp > best_freq) {
1781 best_freq = tmp;
1782 best_cpsdvsr = cpsdvsr;
1783 best_scr = scr;
1784
1785 if (tmp == freq)
1786 found = 1;
1787 }
1788 /*
1789 * increased scr will give lower rates, which are not
1790 * required
1791 */
1792 break;
1793 }
1794 cpsdvsr += 2;
1795 scr = SCR_MIN;
1796 }
1797
1798 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1799 freq);
1800
1801 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1802 clk_freq->scr = (u8) (best_scr & 0xFF);
1803 dev_dbg(&pl022->adev->dev,
1804 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1805 freq, best_freq);
1806 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1807 clk_freq->cpsdvsr, clk_freq->scr);
1808
1809 return 0;
1810}
1811
1812/*
1813 * A piece of default chip info unless the platform
1814 * supplies it.
1815 */
1816static const struct pl022_config_chip pl022_default_chip_info = {
1817 .com_mode = INTERRUPT_TRANSFER,
1818 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1819 .hierarchy = SSP_MASTER,
1820 .slave_tx_disable = DO_NOT_DRIVE_TX,
1821 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1822 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1823 .ctrl_len = SSP_BITS_8,
1824 .wait_state = SSP_MWIRE_WAIT_ZERO,
1825 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1826};
1827
1828/**
1829 * pl022_setup - setup function registered to SPI master framework
1830 * @spi: spi device which is requesting setup
1831 *
1832 * This function is registered to the SPI framework for this SPI master
1833 * controller. If it is the first time when setup is called by this device,
1834 * this function will initialize the runtime state for this chip and save
1835 * the same in the device structure. Else it will update the runtime info
1836 * with the updated chip info. Nothing is really being written to the
1837 * controller hardware here, that is not done until the actual transfer
1838 * commence.
1839 */
1840static int pl022_setup(struct spi_device *spi)
1841{
1842 struct pl022_config_chip const *chip_info;
1843 struct pl022_config_chip chip_info_dt;
1844 struct chip_data *chip;
1845 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1846 int status = 0;
1847 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1848 unsigned int bits = spi->bits_per_word;
1849 u32 tmp;
1850 struct device_node *np = spi->dev.of_node;
1851
1852 if (!spi->max_speed_hz)
1853 return -EINVAL;
1854
1855 /* Get controller_state if one is supplied */
1856 chip = spi_get_ctldata(spi);
1857
1858 if (chip == NULL) {
1859 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1860 if (!chip)
1861 return -ENOMEM;
1862 dev_dbg(&spi->dev,
1863 "allocated memory for controller's runtime state\n");
1864 }
1865
1866 /* Get controller data if one is supplied */
1867 chip_info = spi->controller_data;
1868
1869 if (chip_info == NULL) {
1870 if (np) {
1871 chip_info_dt = pl022_default_chip_info;
1872
1873 chip_info_dt.hierarchy = SSP_MASTER;
1874 of_property_read_u32(np, "pl022,interface",
1875 &chip_info_dt.iface);
1876 of_property_read_u32(np, "pl022,com-mode",
1877 &chip_info_dt.com_mode);
1878 of_property_read_u32(np, "pl022,rx-level-trig",
1879 &chip_info_dt.rx_lev_trig);
1880 of_property_read_u32(np, "pl022,tx-level-trig",
1881 &chip_info_dt.tx_lev_trig);
1882 of_property_read_u32(np, "pl022,ctrl-len",
1883 &chip_info_dt.ctrl_len);
1884 of_property_read_u32(np, "pl022,wait-state",
1885 &chip_info_dt.wait_state);
1886 of_property_read_u32(np, "pl022,duplex",
1887 &chip_info_dt.duplex);
1888
1889 chip_info = &chip_info_dt;
1890 } else {
1891 chip_info = &pl022_default_chip_info;
1892 /* spi_board_info.controller_data not is supplied */
1893 dev_dbg(&spi->dev,
1894 "using default controller_data settings\n");
1895 }
1896 } else
1897 dev_dbg(&spi->dev,
1898 "using user supplied controller_data settings\n");
1899
1900 /*
1901 * We can override with custom divisors, else we use the board
1902 * frequency setting
1903 */
1904 if ((0 == chip_info->clk_freq.cpsdvsr)
1905 && (0 == chip_info->clk_freq.scr)) {
1906 status = calculate_effective_freq(pl022,
1907 spi->max_speed_hz,
1908 &clk_freq);
1909 if (status < 0)
1910 goto err_config_params;
1911 } else {
1912 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1913 if ((clk_freq.cpsdvsr % 2) != 0)
1914 clk_freq.cpsdvsr =
1915 clk_freq.cpsdvsr - 1;
1916 }
1917 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1918 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1919 status = -EINVAL;
1920 dev_err(&spi->dev,
1921 "cpsdvsr is configured incorrectly\n");
1922 goto err_config_params;
1923 }
1924
1925 status = verify_controller_parameters(pl022, chip_info);
1926 if (status) {
1927 dev_err(&spi->dev, "controller data is incorrect");
1928 goto err_config_params;
1929 }
1930
1931 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1932 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1933
1934 /* Now set controller state based on controller data */
1935 chip->xfer_type = chip_info->com_mode;
1936
1937 /* Check bits per word with vendor specific range */
1938 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1939 status = -ENOTSUPP;
1940 dev_err(&spi->dev, "illegal data size for this controller!\n");
1941 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1942 pl022->vendor->max_bpw);
1943 goto err_config_params;
1944 } else if (bits <= 8) {
1945 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1946 chip->n_bytes = 1;
1947 chip->read = READING_U8;
1948 chip->write = WRITING_U8;
1949 } else if (bits <= 16) {
1950 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1951 chip->n_bytes = 2;
1952 chip->read = READING_U16;
1953 chip->write = WRITING_U16;
1954 } else {
1955 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1956 chip->n_bytes = 4;
1957 chip->read = READING_U32;
1958 chip->write = WRITING_U32;
1959 }
1960
1961 /* Now Initialize all register settings required for this chip */
1962 chip->cr0 = 0;
1963 chip->cr1 = 0;
1964 chip->dmacr = 0;
1965 chip->cpsr = 0;
1966 if ((chip_info->com_mode == DMA_TRANSFER)
1967 && ((pl022->master_info)->enable_dma)) {
1968 chip->enable_dma = true;
1969 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1970 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1971 SSP_DMACR_MASK_RXDMAE, 0);
1972 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1973 SSP_DMACR_MASK_TXDMAE, 1);
1974 } else {
1975 chip->enable_dma = false;
1976 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1977 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1978 SSP_DMACR_MASK_RXDMAE, 0);
1979 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1980 SSP_DMACR_MASK_TXDMAE, 1);
1981 }
1982
1983 chip->cpsr = clk_freq.cpsdvsr;
1984
1985 /* Special setup for the ST micro extended control registers */
1986 if (pl022->vendor->extended_cr) {
1987 u32 etx;
1988
1989 if (pl022->vendor->pl023) {
1990 /* These bits are only in the PL023 */
1991 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1992 SSP_CR1_MASK_FBCLKDEL_ST, 13);
1993 } else {
1994 /* These bits are in the PL022 but not PL023 */
1995 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1996 SSP_CR0_MASK_HALFDUP_ST, 5);
1997 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1998 SSP_CR0_MASK_CSS_ST, 16);
1999 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2000 SSP_CR0_MASK_FRF_ST, 21);
2001 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
2002 SSP_CR1_MASK_MWAIT_ST, 6);
2003 }
2004 SSP_WRITE_BITS(chip->cr0, bits - 1,
2005 SSP_CR0_MASK_DSS_ST, 0);
2006
2007 if (spi->mode & SPI_LSB_FIRST) {
2008 tmp = SSP_RX_LSB;
2009 etx = SSP_TX_LSB;
2010 } else {
2011 tmp = SSP_RX_MSB;
2012 etx = SSP_TX_MSB;
2013 }
2014 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2015 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2016 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2017 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2018 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2019 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2020 } else {
2021 SSP_WRITE_BITS(chip->cr0, bits - 1,
2022 SSP_CR0_MASK_DSS, 0);
2023 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2024 SSP_CR0_MASK_FRF, 4);
2025 }
2026
2027 /* Stuff that is common for all versions */
2028 if (spi->mode & SPI_CPOL)
2029 tmp = SSP_CLK_POL_IDLE_HIGH;
2030 else
2031 tmp = SSP_CLK_POL_IDLE_LOW;
2032 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2033
2034 if (spi->mode & SPI_CPHA)
2035 tmp = SSP_CLK_SECOND_EDGE;
2036 else
2037 tmp = SSP_CLK_FIRST_EDGE;
2038 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2039
2040 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2041 /* Loopback is available on all versions except PL023 */
2042 if (pl022->vendor->loopback) {
2043 if (spi->mode & SPI_LOOP)
2044 tmp = LOOPBACK_ENABLED;
2045 else
2046 tmp = LOOPBACK_DISABLED;
2047 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2048 }
2049 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2050 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2051 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2052 3);
2053
2054 /* Save controller_state */
2055 spi_set_ctldata(spi, chip);
2056 return status;
2057 err_config_params:
2058 spi_set_ctldata(spi, NULL);
2059 kfree(chip);
2060 return status;
2061}
2062
2063/**
2064 * pl022_cleanup - cleanup function registered to SPI master framework
2065 * @spi: spi device which is requesting cleanup
2066 *
2067 * This function is registered to the SPI framework for this SPI master
2068 * controller. It will free the runtime state of chip.
2069 */
2070static void pl022_cleanup(struct spi_device *spi)
2071{
2072 struct chip_data *chip = spi_get_ctldata(spi);
2073
2074 spi_set_ctldata(spi, NULL);
2075 kfree(chip);
2076}
2077
2078static struct pl022_ssp_controller *
2079pl022_platform_data_dt_get(struct device *dev)
2080{
2081 struct device_node *np = dev->of_node;
2082 struct pl022_ssp_controller *pd;
2083
2084 if (!np) {
2085 dev_err(dev, "no dt node defined\n");
2086 return NULL;
2087 }
2088
2089 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2090 if (!pd)
2091 return NULL;
2092
2093 pd->bus_id = -1;
2094 pd->enable_dma = 1;
2095 of_property_read_u32(np, "pl022,autosuspend-delay",
2096 &pd->autosuspend_delay);
2097 pd->rt = of_property_read_bool(np, "pl022,rt");
2098
2099 return pd;
2100}
2101
2102static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2103{
2104 struct device *dev = &adev->dev;
2105 struct pl022_ssp_controller *platform_info =
2106 dev_get_platdata(&adev->dev);
2107 struct spi_master *master;
2108 struct pl022 *pl022 = NULL; /*Data for this driver */
2109 int status = 0;
2110
2111 dev_info(&adev->dev,
2112 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2113 if (!platform_info && IS_ENABLED(CONFIG_OF))
2114 platform_info = pl022_platform_data_dt_get(dev);
2115
2116 if (!platform_info) {
2117 dev_err(dev, "probe: no platform data defined\n");
2118 return -ENODEV;
2119 }
2120
2121 /* Allocate master with space for data */
2122 master = spi_alloc_master(dev, sizeof(struct pl022));
2123 if (master == NULL) {
2124 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2125 return -ENOMEM;
2126 }
2127
2128 pl022 = spi_master_get_devdata(master);
2129 pl022->master = master;
2130 pl022->master_info = platform_info;
2131 pl022->adev = adev;
2132 pl022->vendor = id->data;
2133
2134 /*
2135 * Bus Number Which has been Assigned to this SSP controller
2136 * on this board
2137 */
2138 master->bus_num = platform_info->bus_id;
2139 master->cleanup = pl022_cleanup;
2140 master->setup = pl022_setup;
2141 master->auto_runtime_pm = true;
2142 master->transfer_one_message = pl022_transfer_one_message;
2143 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2144 master->rt = platform_info->rt;
2145 master->dev.of_node = dev->of_node;
2146 master->use_gpio_descriptors = true;
2147
2148 /*
2149 * Supports mode 0-3, loopback, and active low CS. Transfers are
2150 * always MS bit first on the original pl022.
2151 */
2152 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2153 if (pl022->vendor->extended_cr)
2154 master->mode_bits |= SPI_LSB_FIRST;
2155
2156 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2157
2158 status = amba_request_regions(adev, NULL);
2159 if (status)
2160 goto err_no_ioregion;
2161
2162 pl022->phybase = adev->res.start;
2163 pl022->virtbase = devm_ioremap(dev, adev->res.start,
2164 resource_size(&adev->res));
2165 if (pl022->virtbase == NULL) {
2166 status = -ENOMEM;
2167 goto err_no_ioremap;
2168 }
2169 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2170 &adev->res.start, pl022->virtbase);
2171
2172 pl022->clk = devm_clk_get(&adev->dev, NULL);
2173 if (IS_ERR(pl022->clk)) {
2174 status = PTR_ERR(pl022->clk);
2175 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2176 goto err_no_clk;
2177 }
2178
2179 status = clk_prepare_enable(pl022->clk);
2180 if (status) {
2181 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2182 goto err_no_clk_en;
2183 }
2184
2185 /* Initialize transfer pump */
2186 tasklet_init(&pl022->pump_transfers, pump_transfers,
2187 (unsigned long)pl022);
2188
2189 /* Disable SSP */
2190 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2191 SSP_CR1(pl022->virtbase));
2192 load_ssp_default_config(pl022);
2193
2194 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2195 0, "pl022", pl022);
2196 if (status < 0) {
2197 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2198 goto err_no_irq;
2199 }
2200
2201 /* Get DMA channels, try autoconfiguration first */
2202 status = pl022_dma_autoprobe(pl022);
2203 if (status == -EPROBE_DEFER) {
2204 dev_dbg(dev, "deferring probe to get DMA channel\n");
2205 goto err_no_irq;
2206 }
2207
2208 /* If that failed, use channels from platform_info */
2209 if (status == 0)
2210 platform_info->enable_dma = 1;
2211 else if (platform_info->enable_dma) {
2212 status = pl022_dma_probe(pl022);
2213 if (status != 0)
2214 platform_info->enable_dma = 0;
2215 }
2216
2217 /* Register with the SPI framework */
2218 amba_set_drvdata(adev, pl022);
2219 status = devm_spi_register_master(&adev->dev, master);
2220 if (status != 0) {
2221 dev_err(&adev->dev,
2222 "probe - problem registering spi master\n");
2223 goto err_spi_register;
2224 }
2225 dev_dbg(dev, "probe succeeded\n");
2226
2227 /* let runtime pm put suspend */
2228 if (platform_info->autosuspend_delay > 0) {
2229 dev_info(&adev->dev,
2230 "will use autosuspend for runtime pm, delay %dms\n",
2231 platform_info->autosuspend_delay);
2232 pm_runtime_set_autosuspend_delay(dev,
2233 platform_info->autosuspend_delay);
2234 pm_runtime_use_autosuspend(dev);
2235 }
2236 pm_runtime_put(dev);
2237
2238 return 0;
2239
2240 err_spi_register:
2241 if (platform_info->enable_dma)
2242 pl022_dma_remove(pl022);
2243 err_no_irq:
2244 clk_disable_unprepare(pl022->clk);
2245 err_no_clk_en:
2246 err_no_clk:
2247 err_no_ioremap:
2248 amba_release_regions(adev);
2249 err_no_ioregion:
2250 spi_master_put(master);
2251 return status;
2252}
2253
2254static void
2255pl022_remove(struct amba_device *adev)
2256{
2257 struct pl022 *pl022 = amba_get_drvdata(adev);
2258
2259 if (!pl022)
2260 return;
2261
2262 /*
2263 * undo pm_runtime_put() in probe. I assume that we're not
2264 * accessing the primecell here.
2265 */
2266 pm_runtime_get_noresume(&adev->dev);
2267
2268 load_ssp_default_config(pl022);
2269 if (pl022->master_info->enable_dma)
2270 pl022_dma_remove(pl022);
2271
2272 clk_disable_unprepare(pl022->clk);
2273 amba_release_regions(adev);
2274 tasklet_disable(&pl022->pump_transfers);
2275}
2276
2277#ifdef CONFIG_PM_SLEEP
2278static int pl022_suspend(struct device *dev)
2279{
2280 struct pl022 *pl022 = dev_get_drvdata(dev);
2281 int ret;
2282
2283 ret = spi_master_suspend(pl022->master);
2284 if (ret)
2285 return ret;
2286
2287 ret = pm_runtime_force_suspend(dev);
2288 if (ret) {
2289 spi_master_resume(pl022->master);
2290 return ret;
2291 }
2292
2293 pinctrl_pm_select_sleep_state(dev);
2294
2295 dev_dbg(dev, "suspended\n");
2296 return 0;
2297}
2298
2299static int pl022_resume(struct device *dev)
2300{
2301 struct pl022 *pl022 = dev_get_drvdata(dev);
2302 int ret;
2303
2304 ret = pm_runtime_force_resume(dev);
2305 if (ret)
2306 dev_err(dev, "problem resuming\n");
2307
2308 /* Start the queue running */
2309 ret = spi_master_resume(pl022->master);
2310 if (!ret)
2311 dev_dbg(dev, "resumed\n");
2312
2313 return ret;
2314}
2315#endif
2316
2317#ifdef CONFIG_PM
2318static int pl022_runtime_suspend(struct device *dev)
2319{
2320 struct pl022 *pl022 = dev_get_drvdata(dev);
2321
2322 clk_disable_unprepare(pl022->clk);
2323 pinctrl_pm_select_idle_state(dev);
2324
2325 return 0;
2326}
2327
2328static int pl022_runtime_resume(struct device *dev)
2329{
2330 struct pl022 *pl022 = dev_get_drvdata(dev);
2331
2332 pinctrl_pm_select_default_state(dev);
2333 clk_prepare_enable(pl022->clk);
2334
2335 return 0;
2336}
2337#endif
2338
2339static const struct dev_pm_ops pl022_dev_pm_ops = {
2340 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2341 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2342};
2343
2344static struct vendor_data vendor_arm = {
2345 .fifodepth = 8,
2346 .max_bpw = 16,
2347 .unidir = false,
2348 .extended_cr = false,
2349 .pl023 = false,
2350 .loopback = true,
2351 .internal_cs_ctrl = false,
2352};
2353
2354static struct vendor_data vendor_st = {
2355 .fifodepth = 32,
2356 .max_bpw = 32,
2357 .unidir = false,
2358 .extended_cr = true,
2359 .pl023 = false,
2360 .loopback = true,
2361 .internal_cs_ctrl = false,
2362};
2363
2364static struct vendor_data vendor_st_pl023 = {
2365 .fifodepth = 32,
2366 .max_bpw = 32,
2367 .unidir = false,
2368 .extended_cr = true,
2369 .pl023 = true,
2370 .loopback = false,
2371 .internal_cs_ctrl = false,
2372};
2373
2374static struct vendor_data vendor_lsi = {
2375 .fifodepth = 8,
2376 .max_bpw = 16,
2377 .unidir = false,
2378 .extended_cr = false,
2379 .pl023 = false,
2380 .loopback = true,
2381 .internal_cs_ctrl = true,
2382};
2383
2384static const struct amba_id pl022_ids[] = {
2385 {
2386 /*
2387 * ARM PL022 variant, this has a 16bit wide
2388 * and 8 locations deep TX/RX FIFO
2389 */
2390 .id = 0x00041022,
2391 .mask = 0x000fffff,
2392 .data = &vendor_arm,
2393 },
2394 {
2395 /*
2396 * ST Micro derivative, this has 32bit wide
2397 * and 32 locations deep TX/RX FIFO
2398 */
2399 .id = 0x01080022,
2400 .mask = 0xffffffff,
2401 .data = &vendor_st,
2402 },
2403 {
2404 /*
2405 * ST-Ericsson derivative "PL023" (this is not
2406 * an official ARM number), this is a PL022 SSP block
2407 * stripped to SPI mode only, it has 32bit wide
2408 * and 32 locations deep TX/RX FIFO but no extended
2409 * CR0/CR1 register
2410 */
2411 .id = 0x00080023,
2412 .mask = 0xffffffff,
2413 .data = &vendor_st_pl023,
2414 },
2415 {
2416 /*
2417 * PL022 variant that has a chip select control register whih
2418 * allows control of 5 output signals nCS[0:4].
2419 */
2420 .id = 0x000b6022,
2421 .mask = 0x000fffff,
2422 .data = &vendor_lsi,
2423 },
2424 { 0, 0 },
2425};
2426
2427MODULE_DEVICE_TABLE(amba, pl022_ids);
2428
2429static struct amba_driver pl022_driver = {
2430 .drv = {
2431 .name = "ssp-pl022",
2432 .pm = &pl022_dev_pm_ops,
2433 },
2434 .id_table = pl022_ids,
2435 .probe = pl022_probe,
2436 .remove = pl022_remove,
2437};
2438
2439static int __init pl022_init(void)
2440{
2441 return amba_driver_register(&pl022_driver);
2442}
2443subsys_initcall(pl022_init);
2444
2445static void __exit pl022_exit(void)
2446{
2447 amba_driver_unregister(&pl022_driver);
2448}
2449module_exit(pl022_exit);
2450
2451MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2452MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2453MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 *
5 * Copyright (C) 2008-2012 ST-Ericsson AB
6 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
7 *
8 * Author: Linus Walleij <linus.walleij@stericsson.com>
9 *
10 * Initial version inspired by:
11 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
12 * Initial adoption to PL022 by:
13 * Sachin Verma <sachin.verma@st.com>
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/device.h>
19#include <linux/ioport.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/spi/spi.h>
23#include <linux/delay.h>
24#include <linux/clk.h>
25#include <linux/err.h>
26#include <linux/amba/bus.h>
27#include <linux/amba/pl022.h>
28#include <linux/io.h>
29#include <linux/slab.h>
30#include <linux/dmaengine.h>
31#include <linux/dma-mapping.h>
32#include <linux/scatterlist.h>
33#include <linux/pm_runtime.h>
34#include <linux/of.h>
35#include <linux/pinctrl/consumer.h>
36
37/*
38 * This macro is used to define some register default values.
39 * reg is masked with mask, the OR:ed with an (again masked)
40 * val shifted sb steps to the left.
41 */
42#define SSP_WRITE_BITS(reg, val, mask, sb) \
43 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
44
45/*
46 * This macro is also used to define some default values.
47 * It will just shift val by sb steps to the left and mask
48 * the result with mask.
49 */
50#define GEN_MASK_BITS(val, mask, sb) \
51 (((val)<<(sb)) & (mask))
52
53#define DRIVE_TX 0
54#define DO_NOT_DRIVE_TX 1
55
56#define DO_NOT_QUEUE_DMA 0
57#define QUEUE_DMA 1
58
59#define RX_TRANSFER 1
60#define TX_TRANSFER 2
61
62/*
63 * Macros to access SSP Registers with their offsets
64 */
65#define SSP_CR0(r) (r + 0x000)
66#define SSP_CR1(r) (r + 0x004)
67#define SSP_DR(r) (r + 0x008)
68#define SSP_SR(r) (r + 0x00C)
69#define SSP_CPSR(r) (r + 0x010)
70#define SSP_IMSC(r) (r + 0x014)
71#define SSP_RIS(r) (r + 0x018)
72#define SSP_MIS(r) (r + 0x01C)
73#define SSP_ICR(r) (r + 0x020)
74#define SSP_DMACR(r) (r + 0x024)
75#define SSP_CSR(r) (r + 0x030) /* vendor extension */
76#define SSP_ITCR(r) (r + 0x080)
77#define SSP_ITIP(r) (r + 0x084)
78#define SSP_ITOP(r) (r + 0x088)
79#define SSP_TDR(r) (r + 0x08C)
80
81#define SSP_PID0(r) (r + 0xFE0)
82#define SSP_PID1(r) (r + 0xFE4)
83#define SSP_PID2(r) (r + 0xFE8)
84#define SSP_PID3(r) (r + 0xFEC)
85
86#define SSP_CID0(r) (r + 0xFF0)
87#define SSP_CID1(r) (r + 0xFF4)
88#define SSP_CID2(r) (r + 0xFF8)
89#define SSP_CID3(r) (r + 0xFFC)
90
91/*
92 * SSP Control Register 0 - SSP_CR0
93 */
94#define SSP_CR0_MASK_DSS (0x0FUL << 0)
95#define SSP_CR0_MASK_FRF (0x3UL << 4)
96#define SSP_CR0_MASK_SPO (0x1UL << 6)
97#define SSP_CR0_MASK_SPH (0x1UL << 7)
98#define SSP_CR0_MASK_SCR (0xFFUL << 8)
99
100/*
101 * The ST version of this block moves som bits
102 * in SSP_CR0 and extends it to 32 bits
103 */
104#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
105#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
106#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
107#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
108
109/*
110 * SSP Control Register 0 - SSP_CR1
111 */
112#define SSP_CR1_MASK_LBM (0x1UL << 0)
113#define SSP_CR1_MASK_SSE (0x1UL << 1)
114#define SSP_CR1_MASK_MS (0x1UL << 2)
115#define SSP_CR1_MASK_SOD (0x1UL << 3)
116
117/*
118 * The ST version of this block adds some bits
119 * in SSP_CR1
120 */
121#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
122#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
123#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
124#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
125#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
126/* This one is only in the PL023 variant */
127#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
128
129/*
130 * SSP Status Register - SSP_SR
131 */
132#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
133#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
134#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
135#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
136#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
137
138/*
139 * SSP Clock Prescale Register - SSP_CPSR
140 */
141#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
142
143/*
144 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
145 */
146#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
147#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
148#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
149#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
150
151/*
152 * SSP Raw Interrupt Status Register - SSP_RIS
153 */
154/* Receive Overrun Raw Interrupt status */
155#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
156/* Receive Timeout Raw Interrupt status */
157#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
158/* Receive FIFO Raw Interrupt status */
159#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
160/* Transmit FIFO Raw Interrupt status */
161#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
162
163/*
164 * SSP Masked Interrupt Status Register - SSP_MIS
165 */
166/* Receive Overrun Masked Interrupt status */
167#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
168/* Receive Timeout Masked Interrupt status */
169#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
170/* Receive FIFO Masked Interrupt status */
171#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
172/* Transmit FIFO Masked Interrupt status */
173#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
174
175/*
176 * SSP Interrupt Clear Register - SSP_ICR
177 */
178/* Receive Overrun Raw Clear Interrupt bit */
179#define SSP_ICR_MASK_RORIC (0x1UL << 0)
180/* Receive Timeout Clear Interrupt bit */
181#define SSP_ICR_MASK_RTIC (0x1UL << 1)
182
183/*
184 * SSP DMA Control Register - SSP_DMACR
185 */
186/* Receive DMA Enable bit */
187#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
188/* Transmit DMA Enable bit */
189#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
190
191/*
192 * SSP Chip Select Control Register - SSP_CSR
193 * (vendor extension)
194 */
195#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
196
197/*
198 * SSP Integration Test control Register - SSP_ITCR
199 */
200#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
201#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
202
203/*
204 * SSP Integration Test Input Register - SSP_ITIP
205 */
206#define ITIP_MASK_SSPRXD (0x1UL << 0)
207#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
208#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
209#define ITIP_MASK_RXDMAC (0x1UL << 3)
210#define ITIP_MASK_TXDMAC (0x1UL << 4)
211#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
212
213/*
214 * SSP Integration Test output Register - SSP_ITOP
215 */
216#define ITOP_MASK_SSPTXD (0x1UL << 0)
217#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
218#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
219#define ITOP_MASK_SSPOEn (0x1UL << 3)
220#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
221#define ITOP_MASK_RORINTR (0x1UL << 5)
222#define ITOP_MASK_RTINTR (0x1UL << 6)
223#define ITOP_MASK_RXINTR (0x1UL << 7)
224#define ITOP_MASK_TXINTR (0x1UL << 8)
225#define ITOP_MASK_INTR (0x1UL << 9)
226#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
227#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
228#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
229#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
230
231/*
232 * SSP Test Data Register - SSP_TDR
233 */
234#define TDR_MASK_TESTDATA (0xFFFFFFFF)
235
236/*
237 * Message State
238 * we use the spi_message.state (void *) pointer to
239 * hold a single state value, that's why all this
240 * (void *) casting is done here.
241 */
242#define STATE_START ((void *) 0)
243#define STATE_RUNNING ((void *) 1)
244#define STATE_DONE ((void *) 2)
245#define STATE_ERROR ((void *) -1)
246#define STATE_TIMEOUT ((void *) -2)
247
248/*
249 * SSP State - Whether Enabled or Disabled
250 */
251#define SSP_DISABLED (0)
252#define SSP_ENABLED (1)
253
254/*
255 * SSP DMA State - Whether DMA Enabled or Disabled
256 */
257#define SSP_DMA_DISABLED (0)
258#define SSP_DMA_ENABLED (1)
259
260/*
261 * SSP Clock Defaults
262 */
263#define SSP_DEFAULT_CLKRATE 0x2
264#define SSP_DEFAULT_PRESCALE 0x40
265
266/*
267 * SSP Clock Parameter ranges
268 */
269#define CPSDVR_MIN 0x02
270#define CPSDVR_MAX 0xFE
271#define SCR_MIN 0x00
272#define SCR_MAX 0xFF
273
274/*
275 * SSP Interrupt related Macros
276 */
277#define DEFAULT_SSP_REG_IMSC 0x0UL
278#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
279#define ENABLE_ALL_INTERRUPTS ( \
280 SSP_IMSC_MASK_RORIM | \
281 SSP_IMSC_MASK_RTIM | \
282 SSP_IMSC_MASK_RXIM | \
283 SSP_IMSC_MASK_TXIM \
284)
285
286#define CLEAR_ALL_INTERRUPTS 0x3
287
288#define SPI_POLLING_TIMEOUT 1000
289
290/*
291 * The type of reading going on this chip
292 */
293enum ssp_reading {
294 READING_NULL,
295 READING_U8,
296 READING_U16,
297 READING_U32
298};
299
300/*
301 * The type of writing going on this chip
302 */
303enum ssp_writing {
304 WRITING_NULL,
305 WRITING_U8,
306 WRITING_U16,
307 WRITING_U32
308};
309
310/**
311 * struct vendor_data - vendor-specific config parameters
312 * for PL022 derivates
313 * @fifodepth: depth of FIFOs (both)
314 * @max_bpw: maximum number of bits per word
315 * @unidir: supports unidirection transfers
316 * @extended_cr: 32 bit wide control register 0 with extra
317 * features and extra features in CR1 as found in the ST variants
318 * @pl023: supports a subset of the ST extensions called "PL023"
319 * @loopback: supports loopback mode
320 * @internal_cs_ctrl: supports chip select control register
321 */
322struct vendor_data {
323 int fifodepth;
324 int max_bpw;
325 bool unidir;
326 bool extended_cr;
327 bool pl023;
328 bool loopback;
329 bool internal_cs_ctrl;
330};
331
332/**
333 * struct pl022 - This is the private SSP driver data structure
334 * @adev: AMBA device model hookup
335 * @vendor: vendor data for the IP block
336 * @phybase: the physical memory where the SSP device resides
337 * @virtbase: the virtual memory where the SSP is mapped
338 * @clk: outgoing clock "SPICLK" for the SPI bus
339 * @host: SPI framework hookup
340 * @host_info: controller-specific data from machine setup
341 * @cur_transfer: Pointer to current spi_transfer
342 * @cur_chip: pointer to current clients chip(assigned from controller_state)
343 * @tx: current position in TX buffer to be read
344 * @tx_end: end position in TX buffer to be read
345 * @rx: current position in RX buffer to be written
346 * @rx_end: end position in RX buffer to be written
347 * @read: the type of read currently going on
348 * @write: the type of write currently going on
349 * @exp_fifo_level: expected FIFO level
350 * @rx_lev_trig: receive FIFO watermark level which triggers IRQ
351 * @tx_lev_trig: transmit FIFO watermark level which triggers IRQ
352 * @dma_rx_channel: optional channel for RX DMA
353 * @dma_tx_channel: optional channel for TX DMA
354 * @sgt_rx: scattertable for the RX transfer
355 * @sgt_tx: scattertable for the TX transfer
356 * @dummypage: a dummy page used for driving data on the bus with DMA
357 * @dma_running: indicates whether DMA is in operation
358 * @cur_cs: current chip select index
359 */
360struct pl022 {
361 struct amba_device *adev;
362 struct vendor_data *vendor;
363 resource_size_t phybase;
364 void __iomem *virtbase;
365 struct clk *clk;
366 struct spi_controller *host;
367 struct pl022_ssp_controller *host_info;
368 struct spi_transfer *cur_transfer;
369 struct chip_data *cur_chip;
370 void *tx;
371 void *tx_end;
372 void *rx;
373 void *rx_end;
374 enum ssp_reading read;
375 enum ssp_writing write;
376 u32 exp_fifo_level;
377 enum ssp_rx_level_trig rx_lev_trig;
378 enum ssp_tx_level_trig tx_lev_trig;
379 /* DMA settings */
380#ifdef CONFIG_DMA_ENGINE
381 struct dma_chan *dma_rx_channel;
382 struct dma_chan *dma_tx_channel;
383 struct sg_table sgt_rx;
384 struct sg_table sgt_tx;
385 char *dummypage;
386 bool dma_running;
387#endif
388 int cur_cs;
389};
390
391/**
392 * struct chip_data - To maintain runtime state of SSP for each client chip
393 * @cr0: Value of control register CR0 of SSP - on later ST variants this
394 * register is 32 bits wide rather than just 16
395 * @cr1: Value of control register CR1 of SSP
396 * @dmacr: Value of DMA control Register of SSP
397 * @cpsr: Value of Clock prescale register
398 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
399 * @enable_dma: Whether to enable DMA or not
400 * @read: function ptr to be used to read when doing xfer for this chip
401 * @write: function ptr to be used to write when doing xfer for this chip
402 * @xfer_type: polling/interrupt/DMA
403 *
404 * Runtime state of the SSP controller, maintained per chip,
405 * This would be set according to the current message that would be served
406 */
407struct chip_data {
408 u32 cr0;
409 u16 cr1;
410 u16 dmacr;
411 u16 cpsr;
412 u8 n_bytes;
413 bool enable_dma;
414 enum ssp_reading read;
415 enum ssp_writing write;
416 int xfer_type;
417};
418
419/**
420 * internal_cs_control - Control chip select signals via SSP_CSR.
421 * @pl022: SSP driver private data structure
422 * @enable: select/delect the chip
423 *
424 * Used on controller with internal chip select control via SSP_CSR register
425 * (vendor extension). Each of the 5 LSB in the register controls one chip
426 * select signal.
427 */
428static void internal_cs_control(struct pl022 *pl022, bool enable)
429{
430 u32 tmp;
431
432 tmp = readw(SSP_CSR(pl022->virtbase));
433 if (enable)
434 tmp &= ~BIT(pl022->cur_cs);
435 else
436 tmp |= BIT(pl022->cur_cs);
437 writew(tmp, SSP_CSR(pl022->virtbase));
438}
439
440static void pl022_cs_control(struct spi_device *spi, bool enable)
441{
442 struct pl022 *pl022 = spi_controller_get_devdata(spi->controller);
443 if (pl022->vendor->internal_cs_ctrl)
444 internal_cs_control(pl022, enable);
445}
446
447/**
448 * flush - flush the FIFO to reach a clean state
449 * @pl022: SSP driver private data structure
450 */
451static int flush(struct pl022 *pl022)
452{
453 unsigned long limit = loops_per_jiffy << 1;
454
455 dev_dbg(&pl022->adev->dev, "flush\n");
456 do {
457 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
458 readw(SSP_DR(pl022->virtbase));
459 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
460
461 pl022->exp_fifo_level = 0;
462
463 return limit;
464}
465
466/**
467 * restore_state - Load configuration of current chip
468 * @pl022: SSP driver private data structure
469 */
470static void restore_state(struct pl022 *pl022)
471{
472 struct chip_data *chip = pl022->cur_chip;
473
474 if (pl022->vendor->extended_cr)
475 writel(chip->cr0, SSP_CR0(pl022->virtbase));
476 else
477 writew(chip->cr0, SSP_CR0(pl022->virtbase));
478 writew(chip->cr1, SSP_CR1(pl022->virtbase));
479 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
480 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
481 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
482 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
483}
484
485/*
486 * Default SSP Register Values
487 */
488#define DEFAULT_SSP_REG_CR0 ( \
489 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
490 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
491 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
492 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
493 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
494)
495
496/* ST versions have slightly different bit layout */
497#define DEFAULT_SSP_REG_CR0_ST ( \
498 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
499 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
500 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
501 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
502 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
503 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
504 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
505)
506
507/* The PL023 version is slightly different again */
508#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
509 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
510 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
511 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
512 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
513)
514
515#define DEFAULT_SSP_REG_CR1 ( \
516 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
517 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
518 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
519 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
520)
521
522/* ST versions extend this register to use all 16 bits */
523#define DEFAULT_SSP_REG_CR1_ST ( \
524 DEFAULT_SSP_REG_CR1 | \
525 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
526 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
527 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
528 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
529 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
530)
531
532/*
533 * The PL023 variant has further differences: no loopback mode, no microwire
534 * support, and a new clock feedback delay setting.
535 */
536#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
537 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
538 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
539 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
540 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
541 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
542 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
543 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
544 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
545)
546
547#define DEFAULT_SSP_REG_CPSR ( \
548 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
549)
550
551#define DEFAULT_SSP_REG_DMACR (\
552 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
553 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
554)
555
556/**
557 * load_ssp_default_config - Load default configuration for SSP
558 * @pl022: SSP driver private data structure
559 */
560static void load_ssp_default_config(struct pl022 *pl022)
561{
562 if (pl022->vendor->pl023) {
563 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
564 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
565 } else if (pl022->vendor->extended_cr) {
566 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
567 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
568 } else {
569 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
570 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
571 }
572 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
573 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
574 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
575 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
576}
577
578/*
579 * This will write to TX and read from RX according to the parameters
580 * set in pl022.
581 */
582static void readwriter(struct pl022 *pl022)
583{
584
585 /*
586 * The FIFO depth is different between primecell variants.
587 * I believe filling in too much in the FIFO might cause
588 * errons in 8bit wide transfers on ARM variants (just 8 words
589 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
590 *
591 * To prevent this issue, the TX FIFO is only filled to the
592 * unused RX FIFO fill length, regardless of what the TX
593 * FIFO status flag indicates.
594 */
595 dev_dbg(&pl022->adev->dev,
596 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
597 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
598
599 /* Read as much as you can */
600 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
601 && (pl022->rx < pl022->rx_end)) {
602 switch (pl022->read) {
603 case READING_NULL:
604 readw(SSP_DR(pl022->virtbase));
605 break;
606 case READING_U8:
607 *(u8 *) (pl022->rx) =
608 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
609 break;
610 case READING_U16:
611 *(u16 *) (pl022->rx) =
612 (u16) readw(SSP_DR(pl022->virtbase));
613 break;
614 case READING_U32:
615 *(u32 *) (pl022->rx) =
616 readl(SSP_DR(pl022->virtbase));
617 break;
618 }
619 pl022->rx += (pl022->cur_chip->n_bytes);
620 pl022->exp_fifo_level--;
621 }
622 /*
623 * Write as much as possible up to the RX FIFO size
624 */
625 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
626 && (pl022->tx < pl022->tx_end)) {
627 switch (pl022->write) {
628 case WRITING_NULL:
629 writew(0x0, SSP_DR(pl022->virtbase));
630 break;
631 case WRITING_U8:
632 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
633 break;
634 case WRITING_U16:
635 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
636 break;
637 case WRITING_U32:
638 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
639 break;
640 }
641 pl022->tx += (pl022->cur_chip->n_bytes);
642 pl022->exp_fifo_level++;
643 /*
644 * This inner reader takes care of things appearing in the RX
645 * FIFO as we're transmitting. This will happen a lot since the
646 * clock starts running when you put things into the TX FIFO,
647 * and then things are continuously clocked into the RX FIFO.
648 */
649 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
650 && (pl022->rx < pl022->rx_end)) {
651 switch (pl022->read) {
652 case READING_NULL:
653 readw(SSP_DR(pl022->virtbase));
654 break;
655 case READING_U8:
656 *(u8 *) (pl022->rx) =
657 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
658 break;
659 case READING_U16:
660 *(u16 *) (pl022->rx) =
661 (u16) readw(SSP_DR(pl022->virtbase));
662 break;
663 case READING_U32:
664 *(u32 *) (pl022->rx) =
665 readl(SSP_DR(pl022->virtbase));
666 break;
667 }
668 pl022->rx += (pl022->cur_chip->n_bytes);
669 pl022->exp_fifo_level--;
670 }
671 }
672 /*
673 * When we exit here the TX FIFO should be full and the RX FIFO
674 * should be empty
675 */
676}
677
678/*
679 * This DMA functionality is only compiled in if we have
680 * access to the generic DMA devices/DMA engine.
681 */
682#ifdef CONFIG_DMA_ENGINE
683static void unmap_free_dma_scatter(struct pl022 *pl022)
684{
685 /* Unmap and free the SG tables */
686 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
687 pl022->sgt_tx.nents, DMA_TO_DEVICE);
688 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
689 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
690 sg_free_table(&pl022->sgt_rx);
691 sg_free_table(&pl022->sgt_tx);
692}
693
694static void dma_callback(void *data)
695{
696 struct pl022 *pl022 = data;
697
698 BUG_ON(!pl022->sgt_rx.sgl);
699
700#ifdef VERBOSE_DEBUG
701 /*
702 * Optionally dump out buffers to inspect contents, this is
703 * good if you want to convince yourself that the loopback
704 * read/write contents are the same, when adopting to a new
705 * DMA engine.
706 */
707 {
708 struct scatterlist *sg;
709 unsigned int i;
710
711 dma_sync_sg_for_cpu(&pl022->adev->dev,
712 pl022->sgt_rx.sgl,
713 pl022->sgt_rx.nents,
714 DMA_FROM_DEVICE);
715
716 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
717 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
718 print_hex_dump(KERN_ERR, "SPI RX: ",
719 DUMP_PREFIX_OFFSET,
720 16,
721 1,
722 sg_virt(sg),
723 sg_dma_len(sg),
724 1);
725 }
726 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
727 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
728 print_hex_dump(KERN_ERR, "SPI TX: ",
729 DUMP_PREFIX_OFFSET,
730 16,
731 1,
732 sg_virt(sg),
733 sg_dma_len(sg),
734 1);
735 }
736 }
737#endif
738
739 unmap_free_dma_scatter(pl022);
740
741 spi_finalize_current_transfer(pl022->host);
742}
743
744static void setup_dma_scatter(struct pl022 *pl022,
745 void *buffer,
746 unsigned int length,
747 struct sg_table *sgtab)
748{
749 struct scatterlist *sg;
750 int bytesleft = length;
751 void *bufp = buffer;
752 int mapbytes;
753 int i;
754
755 if (buffer) {
756 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
757 /*
758 * If there are less bytes left than what fits
759 * in the current page (plus page alignment offset)
760 * we just feed in this, else we stuff in as much
761 * as we can.
762 */
763 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
764 mapbytes = bytesleft;
765 else
766 mapbytes = PAGE_SIZE - offset_in_page(bufp);
767 sg_set_page(sg, virt_to_page(bufp),
768 mapbytes, offset_in_page(bufp));
769 bufp += mapbytes;
770 bytesleft -= mapbytes;
771 dev_dbg(&pl022->adev->dev,
772 "set RX/TX target page @ %p, %d bytes, %d left\n",
773 bufp, mapbytes, bytesleft);
774 }
775 } else {
776 /* Map the dummy buffer on every page */
777 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
778 if (bytesleft < PAGE_SIZE)
779 mapbytes = bytesleft;
780 else
781 mapbytes = PAGE_SIZE;
782 sg_set_page(sg, virt_to_page(pl022->dummypage),
783 mapbytes, 0);
784 bytesleft -= mapbytes;
785 dev_dbg(&pl022->adev->dev,
786 "set RX/TX to dummy page %d bytes, %d left\n",
787 mapbytes, bytesleft);
788
789 }
790 }
791 BUG_ON(bytesleft);
792}
793
794/**
795 * configure_dma - configures the channels for the next transfer
796 * @pl022: SSP driver's private data structure
797 */
798static int configure_dma(struct pl022 *pl022)
799{
800 struct dma_slave_config rx_conf = {
801 .src_addr = SSP_DR(pl022->phybase),
802 .direction = DMA_DEV_TO_MEM,
803 .device_fc = false,
804 };
805 struct dma_slave_config tx_conf = {
806 .dst_addr = SSP_DR(pl022->phybase),
807 .direction = DMA_MEM_TO_DEV,
808 .device_fc = false,
809 };
810 unsigned int pages;
811 int ret;
812 int rx_sglen, tx_sglen;
813 struct dma_chan *rxchan = pl022->dma_rx_channel;
814 struct dma_chan *txchan = pl022->dma_tx_channel;
815 struct dma_async_tx_descriptor *rxdesc;
816 struct dma_async_tx_descriptor *txdesc;
817
818 /* Check that the channels are available */
819 if (!rxchan || !txchan)
820 return -ENODEV;
821
822 /*
823 * If supplied, the DMA burstsize should equal the FIFO trigger level.
824 * Notice that the DMA engine uses one-to-one mapping. Since we can
825 * not trigger on 2 elements this needs explicit mapping rather than
826 * calculation.
827 */
828 switch (pl022->rx_lev_trig) {
829 case SSP_RX_1_OR_MORE_ELEM:
830 rx_conf.src_maxburst = 1;
831 break;
832 case SSP_RX_4_OR_MORE_ELEM:
833 rx_conf.src_maxburst = 4;
834 break;
835 case SSP_RX_8_OR_MORE_ELEM:
836 rx_conf.src_maxburst = 8;
837 break;
838 case SSP_RX_16_OR_MORE_ELEM:
839 rx_conf.src_maxburst = 16;
840 break;
841 case SSP_RX_32_OR_MORE_ELEM:
842 rx_conf.src_maxburst = 32;
843 break;
844 default:
845 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
846 break;
847 }
848
849 switch (pl022->tx_lev_trig) {
850 case SSP_TX_1_OR_MORE_EMPTY_LOC:
851 tx_conf.dst_maxburst = 1;
852 break;
853 case SSP_TX_4_OR_MORE_EMPTY_LOC:
854 tx_conf.dst_maxburst = 4;
855 break;
856 case SSP_TX_8_OR_MORE_EMPTY_LOC:
857 tx_conf.dst_maxburst = 8;
858 break;
859 case SSP_TX_16_OR_MORE_EMPTY_LOC:
860 tx_conf.dst_maxburst = 16;
861 break;
862 case SSP_TX_32_OR_MORE_EMPTY_LOC:
863 tx_conf.dst_maxburst = 32;
864 break;
865 default:
866 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
867 break;
868 }
869
870 switch (pl022->read) {
871 case READING_NULL:
872 /* Use the same as for writing */
873 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
874 break;
875 case READING_U8:
876 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
877 break;
878 case READING_U16:
879 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
880 break;
881 case READING_U32:
882 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
883 break;
884 }
885
886 switch (pl022->write) {
887 case WRITING_NULL:
888 /* Use the same as for reading */
889 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
890 break;
891 case WRITING_U8:
892 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
893 break;
894 case WRITING_U16:
895 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
896 break;
897 case WRITING_U32:
898 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
899 break;
900 }
901
902 /* SPI pecularity: we need to read and write the same width */
903 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
904 rx_conf.src_addr_width = tx_conf.dst_addr_width;
905 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
906 tx_conf.dst_addr_width = rx_conf.src_addr_width;
907 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
908
909 dmaengine_slave_config(rxchan, &rx_conf);
910 dmaengine_slave_config(txchan, &tx_conf);
911
912 /* Create sglists for the transfers */
913 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
914 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
915
916 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
917 if (ret)
918 goto err_alloc_rx_sg;
919
920 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
921 if (ret)
922 goto err_alloc_tx_sg;
923
924 /* Fill in the scatterlists for the RX+TX buffers */
925 setup_dma_scatter(pl022, pl022->rx,
926 pl022->cur_transfer->len, &pl022->sgt_rx);
927 setup_dma_scatter(pl022, pl022->tx,
928 pl022->cur_transfer->len, &pl022->sgt_tx);
929
930 /* Map DMA buffers */
931 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
932 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
933 if (!rx_sglen)
934 goto err_rx_sgmap;
935
936 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
937 pl022->sgt_tx.nents, DMA_TO_DEVICE);
938 if (!tx_sglen)
939 goto err_tx_sgmap;
940
941 /* Send both scatterlists */
942 rxdesc = dmaengine_prep_slave_sg(rxchan,
943 pl022->sgt_rx.sgl,
944 rx_sglen,
945 DMA_DEV_TO_MEM,
946 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
947 if (!rxdesc)
948 goto err_rxdesc;
949
950 txdesc = dmaengine_prep_slave_sg(txchan,
951 pl022->sgt_tx.sgl,
952 tx_sglen,
953 DMA_MEM_TO_DEV,
954 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
955 if (!txdesc)
956 goto err_txdesc;
957
958 /* Put the callback on the RX transfer only, that should finish last */
959 rxdesc->callback = dma_callback;
960 rxdesc->callback_param = pl022;
961
962 /* Submit and fire RX and TX with TX last so we're ready to read! */
963 dmaengine_submit(rxdesc);
964 dmaengine_submit(txdesc);
965 dma_async_issue_pending(rxchan);
966 dma_async_issue_pending(txchan);
967 pl022->dma_running = true;
968
969 return 0;
970
971err_txdesc:
972 dmaengine_terminate_all(txchan);
973err_rxdesc:
974 dmaengine_terminate_all(rxchan);
975 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
976 pl022->sgt_tx.nents, DMA_TO_DEVICE);
977err_tx_sgmap:
978 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
979 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
980err_rx_sgmap:
981 sg_free_table(&pl022->sgt_tx);
982err_alloc_tx_sg:
983 sg_free_table(&pl022->sgt_rx);
984err_alloc_rx_sg:
985 return -ENOMEM;
986}
987
988static int pl022_dma_probe(struct pl022 *pl022)
989{
990 dma_cap_mask_t mask;
991
992 /* Try to acquire a generic DMA engine slave channel */
993 dma_cap_zero(mask);
994 dma_cap_set(DMA_SLAVE, mask);
995 /*
996 * We need both RX and TX channels to do DMA, else do none
997 * of them.
998 */
999 pl022->dma_rx_channel = dma_request_channel(mask,
1000 pl022->host_info->dma_filter,
1001 pl022->host_info->dma_rx_param);
1002 if (!pl022->dma_rx_channel) {
1003 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1004 goto err_no_rxchan;
1005 }
1006
1007 pl022->dma_tx_channel = dma_request_channel(mask,
1008 pl022->host_info->dma_filter,
1009 pl022->host_info->dma_tx_param);
1010 if (!pl022->dma_tx_channel) {
1011 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1012 goto err_no_txchan;
1013 }
1014
1015 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1016 if (!pl022->dummypage)
1017 goto err_no_dummypage;
1018
1019 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1020 dma_chan_name(pl022->dma_rx_channel),
1021 dma_chan_name(pl022->dma_tx_channel));
1022
1023 return 0;
1024
1025err_no_dummypage:
1026 dma_release_channel(pl022->dma_tx_channel);
1027err_no_txchan:
1028 dma_release_channel(pl022->dma_rx_channel);
1029 pl022->dma_rx_channel = NULL;
1030err_no_rxchan:
1031 dev_err(&pl022->adev->dev,
1032 "Failed to work in dma mode, work without dma!\n");
1033 return -ENODEV;
1034}
1035
1036static int pl022_dma_autoprobe(struct pl022 *pl022)
1037{
1038 struct device *dev = &pl022->adev->dev;
1039 struct dma_chan *chan;
1040 int err;
1041
1042 /* automatically configure DMA channels from platform, normally using DT */
1043 chan = dma_request_chan(dev, "rx");
1044 if (IS_ERR(chan)) {
1045 err = PTR_ERR(chan);
1046 goto err_no_rxchan;
1047 }
1048
1049 pl022->dma_rx_channel = chan;
1050
1051 chan = dma_request_chan(dev, "tx");
1052 if (IS_ERR(chan)) {
1053 err = PTR_ERR(chan);
1054 goto err_no_txchan;
1055 }
1056
1057 pl022->dma_tx_channel = chan;
1058
1059 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1060 if (!pl022->dummypage) {
1061 err = -ENOMEM;
1062 goto err_no_dummypage;
1063 }
1064
1065 return 0;
1066
1067err_no_dummypage:
1068 dma_release_channel(pl022->dma_tx_channel);
1069 pl022->dma_tx_channel = NULL;
1070err_no_txchan:
1071 dma_release_channel(pl022->dma_rx_channel);
1072 pl022->dma_rx_channel = NULL;
1073err_no_rxchan:
1074 return err;
1075}
1076
1077static void terminate_dma(struct pl022 *pl022)
1078{
1079 if (!pl022->dma_running)
1080 return;
1081
1082 struct dma_chan *rxchan = pl022->dma_rx_channel;
1083 struct dma_chan *txchan = pl022->dma_tx_channel;
1084
1085 dmaengine_terminate_all(rxchan);
1086 dmaengine_terminate_all(txchan);
1087 unmap_free_dma_scatter(pl022);
1088 pl022->dma_running = false;
1089}
1090
1091static void pl022_dma_remove(struct pl022 *pl022)
1092{
1093 terminate_dma(pl022);
1094 if (pl022->dma_tx_channel)
1095 dma_release_channel(pl022->dma_tx_channel);
1096 if (pl022->dma_rx_channel)
1097 dma_release_channel(pl022->dma_rx_channel);
1098 kfree(pl022->dummypage);
1099}
1100
1101#else
1102static inline int configure_dma(struct pl022 *pl022)
1103{
1104 return -ENODEV;
1105}
1106
1107static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1108{
1109 return 0;
1110}
1111
1112static inline int pl022_dma_probe(struct pl022 *pl022)
1113{
1114 return 0;
1115}
1116
1117static inline void terminate_dma(struct pl022 *pl022)
1118{
1119}
1120
1121static inline void pl022_dma_remove(struct pl022 *pl022)
1122{
1123}
1124#endif
1125
1126/**
1127 * pl022_interrupt_handler - Interrupt handler for SSP controller
1128 * @irq: IRQ number
1129 * @dev_id: Local device data
1130 *
1131 * This function handles interrupts generated for an interrupt based transfer.
1132 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1133 * current message's state as STATE_ERROR and schedule the tasklet
1134 * pump_transfers which will do the postprocessing of the current message by
1135 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1136 * more data, and writes data in TX FIFO till it is not full. If we complete
1137 * the transfer we move to the next transfer and schedule the tasklet.
1138 */
1139static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1140{
1141 struct pl022 *pl022 = dev_id;
1142 u16 irq_status = 0;
1143 /* Read the Interrupt Status Register */
1144 irq_status = readw(SSP_MIS(pl022->virtbase));
1145
1146 if (unlikely(!irq_status))
1147 return IRQ_NONE;
1148
1149 /*
1150 * This handles the FIFO interrupts, the timeout
1151 * interrupts are flatly ignored, they cannot be
1152 * trusted.
1153 */
1154 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1155 /*
1156 * Overrun interrupt - bail out since our Data has been
1157 * corrupted
1158 */
1159 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1160 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1161 dev_err(&pl022->adev->dev,
1162 "RXFIFO is full\n");
1163
1164 /*
1165 * Disable and clear interrupts, disable SSP,
1166 * mark message with bad status so it can be
1167 * retried.
1168 */
1169 writew(DISABLE_ALL_INTERRUPTS,
1170 SSP_IMSC(pl022->virtbase));
1171 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1172 writew((readw(SSP_CR1(pl022->virtbase)) &
1173 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1174 pl022->cur_transfer->error |= SPI_TRANS_FAIL_IO;
1175 spi_finalize_current_transfer(pl022->host);
1176 return IRQ_HANDLED;
1177 }
1178
1179 readwriter(pl022);
1180
1181 if (pl022->tx == pl022->tx_end) {
1182 /* Disable Transmit interrupt, enable receive interrupt */
1183 writew((readw(SSP_IMSC(pl022->virtbase)) &
1184 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1185 SSP_IMSC(pl022->virtbase));
1186 }
1187
1188 /*
1189 * Since all transactions must write as much as shall be read,
1190 * we can conclude the entire transaction once RX is complete.
1191 * At this point, all TX will always be finished.
1192 */
1193 if (pl022->rx >= pl022->rx_end) {
1194 writew(DISABLE_ALL_INTERRUPTS,
1195 SSP_IMSC(pl022->virtbase));
1196 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1197 if (unlikely(pl022->rx > pl022->rx_end)) {
1198 dev_warn(&pl022->adev->dev, "read %u surplus "
1199 "bytes (did you request an odd "
1200 "number of bytes on a 16bit bus?)\n",
1201 (u32) (pl022->rx - pl022->rx_end));
1202 }
1203 spi_finalize_current_transfer(pl022->host);
1204 return IRQ_HANDLED;
1205 }
1206
1207 return IRQ_HANDLED;
1208}
1209
1210/*
1211 * This sets up the pointers to memory for the next message to
1212 * send out on the SPI bus.
1213 */
1214static int set_up_next_transfer(struct pl022 *pl022,
1215 struct spi_transfer *transfer)
1216{
1217 int residue;
1218
1219 /* Sanity check the message for this bus width */
1220 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1221 if (unlikely(residue != 0)) {
1222 dev_err(&pl022->adev->dev,
1223 "message of %u bytes to transmit but the current "
1224 "chip bus has a data width of %u bytes!\n",
1225 pl022->cur_transfer->len,
1226 pl022->cur_chip->n_bytes);
1227 dev_err(&pl022->adev->dev, "skipping this message\n");
1228 return -EIO;
1229 }
1230 pl022->tx = (void *)transfer->tx_buf;
1231 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1232 pl022->rx = (void *)transfer->rx_buf;
1233 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1234 pl022->write =
1235 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1236 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1237 return 0;
1238}
1239
1240static int do_interrupt_dma_transfer(struct pl022 *pl022)
1241{
1242 int ret;
1243
1244 /*
1245 * Default is to enable all interrupts except RX -
1246 * this will be enabled once TX is complete
1247 */
1248 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1249
1250 ret = set_up_next_transfer(pl022, pl022->cur_transfer);
1251 if (ret)
1252 return ret;
1253
1254 /* If we're using DMA, set up DMA here */
1255 if (pl022->cur_chip->enable_dma) {
1256 /* Configure DMA transfer */
1257 if (configure_dma(pl022)) {
1258 dev_dbg(&pl022->adev->dev,
1259 "configuration of DMA failed, fall back to interrupt mode\n");
1260 goto err_config_dma;
1261 }
1262 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1263 irqflags = DISABLE_ALL_INTERRUPTS;
1264 }
1265err_config_dma:
1266 /* Enable SSP, turn on interrupts */
1267 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1268 SSP_CR1(pl022->virtbase));
1269 writew(irqflags, SSP_IMSC(pl022->virtbase));
1270 return 1;
1271}
1272
1273static void print_current_status(struct pl022 *pl022)
1274{
1275 u32 read_cr0;
1276 u16 read_cr1, read_dmacr, read_sr;
1277
1278 if (pl022->vendor->extended_cr)
1279 read_cr0 = readl(SSP_CR0(pl022->virtbase));
1280 else
1281 read_cr0 = readw(SSP_CR0(pl022->virtbase));
1282 read_cr1 = readw(SSP_CR1(pl022->virtbase));
1283 read_dmacr = readw(SSP_DMACR(pl022->virtbase));
1284 read_sr = readw(SSP_SR(pl022->virtbase));
1285
1286 dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
1287 dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
1288 dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
1289 dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
1290 dev_warn(&pl022->adev->dev,
1291 "spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
1292 pl022->exp_fifo_level,
1293 pl022->vendor->fifodepth);
1294
1295}
1296
1297static int do_polling_transfer(struct pl022 *pl022)
1298{
1299 int ret;
1300 unsigned long time, timeout;
1301
1302 /* Configuration Changing Per Transfer */
1303 ret = set_up_next_transfer(pl022, pl022->cur_transfer);
1304 if (ret)
1305 return ret;
1306 /* Flush FIFOs and enable SSP */
1307 flush(pl022);
1308 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1309 SSP_CR1(pl022->virtbase));
1310
1311 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1312
1313 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1314 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1315 time = jiffies;
1316 readwriter(pl022);
1317 if (time_after(time, timeout)) {
1318 dev_warn(&pl022->adev->dev,
1319 "%s: timeout!\n", __func__);
1320 print_current_status(pl022);
1321 return -ETIMEDOUT;
1322 }
1323 cpu_relax();
1324 }
1325
1326 return 0;
1327}
1328
1329static int pl022_transfer_one(struct spi_controller *host, struct spi_device *spi,
1330 struct spi_transfer *transfer)
1331{
1332 struct pl022 *pl022 = spi_controller_get_devdata(host);
1333
1334 pl022->cur_transfer = transfer;
1335
1336 /* Setup the SPI using the per chip configuration */
1337 pl022->cur_chip = spi_get_ctldata(spi);
1338 pl022->cur_cs = spi_get_chipselect(spi, 0);
1339
1340 restore_state(pl022);
1341 flush(pl022);
1342
1343 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1344 return do_polling_transfer(pl022);
1345 else
1346 return do_interrupt_dma_transfer(pl022);
1347}
1348
1349static void pl022_handle_err(struct spi_controller *ctlr, struct spi_message *message)
1350{
1351 struct pl022 *pl022 = spi_controller_get_devdata(ctlr);
1352
1353 terminate_dma(pl022);
1354 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
1355 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1356}
1357
1358static int pl022_unprepare_transfer_hardware(struct spi_controller *host)
1359{
1360 struct pl022 *pl022 = spi_controller_get_devdata(host);
1361
1362 /* nothing more to do - disable spi/ssp and power off */
1363 writew((readw(SSP_CR1(pl022->virtbase)) &
1364 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1365
1366 return 0;
1367}
1368
1369static int verify_controller_parameters(struct pl022 *pl022,
1370 struct pl022_config_chip const *chip_info)
1371{
1372 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1373 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1374 dev_err(&pl022->adev->dev,
1375 "interface is configured incorrectly\n");
1376 return -EINVAL;
1377 }
1378 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1379 (!pl022->vendor->unidir)) {
1380 dev_err(&pl022->adev->dev,
1381 "unidirectional mode not supported in this "
1382 "hardware version\n");
1383 return -EINVAL;
1384 }
1385 if ((chip_info->hierarchy != SSP_MASTER)
1386 && (chip_info->hierarchy != SSP_SLAVE)) {
1387 dev_err(&pl022->adev->dev,
1388 "hierarchy is configured incorrectly\n");
1389 return -EINVAL;
1390 }
1391 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1392 && (chip_info->com_mode != DMA_TRANSFER)
1393 && (chip_info->com_mode != POLLING_TRANSFER)) {
1394 dev_err(&pl022->adev->dev,
1395 "Communication mode is configured incorrectly\n");
1396 return -EINVAL;
1397 }
1398 switch (chip_info->rx_lev_trig) {
1399 case SSP_RX_1_OR_MORE_ELEM:
1400 case SSP_RX_4_OR_MORE_ELEM:
1401 case SSP_RX_8_OR_MORE_ELEM:
1402 /* These are always OK, all variants can handle this */
1403 break;
1404 case SSP_RX_16_OR_MORE_ELEM:
1405 if (pl022->vendor->fifodepth < 16) {
1406 dev_err(&pl022->adev->dev,
1407 "RX FIFO Trigger Level is configured incorrectly\n");
1408 return -EINVAL;
1409 }
1410 break;
1411 case SSP_RX_32_OR_MORE_ELEM:
1412 if (pl022->vendor->fifodepth < 32) {
1413 dev_err(&pl022->adev->dev,
1414 "RX FIFO Trigger Level is configured incorrectly\n");
1415 return -EINVAL;
1416 }
1417 break;
1418 default:
1419 dev_err(&pl022->adev->dev,
1420 "RX FIFO Trigger Level is configured incorrectly\n");
1421 return -EINVAL;
1422 }
1423 switch (chip_info->tx_lev_trig) {
1424 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1425 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1426 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1427 /* These are always OK, all variants can handle this */
1428 break;
1429 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1430 if (pl022->vendor->fifodepth < 16) {
1431 dev_err(&pl022->adev->dev,
1432 "TX FIFO Trigger Level is configured incorrectly\n");
1433 return -EINVAL;
1434 }
1435 break;
1436 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1437 if (pl022->vendor->fifodepth < 32) {
1438 dev_err(&pl022->adev->dev,
1439 "TX FIFO Trigger Level is configured incorrectly\n");
1440 return -EINVAL;
1441 }
1442 break;
1443 default:
1444 dev_err(&pl022->adev->dev,
1445 "TX FIFO Trigger Level is configured incorrectly\n");
1446 return -EINVAL;
1447 }
1448 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1449 if ((chip_info->ctrl_len < SSP_BITS_4)
1450 || (chip_info->ctrl_len > SSP_BITS_32)) {
1451 dev_err(&pl022->adev->dev,
1452 "CTRL LEN is configured incorrectly\n");
1453 return -EINVAL;
1454 }
1455 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1456 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1457 dev_err(&pl022->adev->dev,
1458 "Wait State is configured incorrectly\n");
1459 return -EINVAL;
1460 }
1461 /* Half duplex is only available in the ST Micro version */
1462 if (pl022->vendor->extended_cr) {
1463 if ((chip_info->duplex !=
1464 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1465 && (chip_info->duplex !=
1466 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1467 dev_err(&pl022->adev->dev,
1468 "Microwire duplex mode is configured incorrectly\n");
1469 return -EINVAL;
1470 }
1471 } else {
1472 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) {
1473 dev_err(&pl022->adev->dev,
1474 "Microwire half duplex mode requested,"
1475 " but this is only available in the"
1476 " ST version of PL022\n");
1477 return -EINVAL;
1478 }
1479 }
1480 }
1481 return 0;
1482}
1483
1484static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1485{
1486 return rate / (cpsdvsr * (1 + scr));
1487}
1488
1489static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1490 ssp_clock_params * clk_freq)
1491{
1492 /* Lets calculate the frequency parameters */
1493 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1494 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1495 best_scr = 0, tmp, found = 0;
1496
1497 rate = clk_get_rate(pl022->clk);
1498 /* cpsdvscr = 2 & scr 0 */
1499 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1500 /* cpsdvsr = 254 & scr = 255 */
1501 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1502
1503 if (freq > max_tclk)
1504 dev_warn(&pl022->adev->dev,
1505 "Max speed that can be programmed is %d Hz, you requested %d\n",
1506 max_tclk, freq);
1507
1508 if (freq < min_tclk) {
1509 dev_err(&pl022->adev->dev,
1510 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1511 freq, min_tclk);
1512 return -EINVAL;
1513 }
1514
1515 /*
1516 * best_freq will give closest possible available rate (<= requested
1517 * freq) for all values of scr & cpsdvsr.
1518 */
1519 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1520 while (scr <= SCR_MAX) {
1521 tmp = spi_rate(rate, cpsdvsr, scr);
1522
1523 if (tmp > freq) {
1524 /* we need lower freq */
1525 scr++;
1526 continue;
1527 }
1528
1529 /*
1530 * If found exact value, mark found and break.
1531 * If found more closer value, update and break.
1532 */
1533 if (tmp > best_freq) {
1534 best_freq = tmp;
1535 best_cpsdvsr = cpsdvsr;
1536 best_scr = scr;
1537
1538 if (tmp == freq)
1539 found = 1;
1540 }
1541 /*
1542 * increased scr will give lower rates, which are not
1543 * required
1544 */
1545 break;
1546 }
1547 cpsdvsr += 2;
1548 scr = SCR_MIN;
1549 }
1550
1551 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1552 freq);
1553
1554 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1555 clk_freq->scr = (u8) (best_scr & 0xFF);
1556 dev_dbg(&pl022->adev->dev,
1557 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1558 freq, best_freq);
1559 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1560 clk_freq->cpsdvsr, clk_freq->scr);
1561
1562 return 0;
1563}
1564
1565/*
1566 * A piece of default chip info unless the platform
1567 * supplies it.
1568 */
1569static const struct pl022_config_chip pl022_default_chip_info = {
1570 .com_mode = INTERRUPT_TRANSFER,
1571 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1572 .hierarchy = SSP_MASTER,
1573 .slave_tx_disable = DO_NOT_DRIVE_TX,
1574 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1575 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1576 .ctrl_len = SSP_BITS_8,
1577 .wait_state = SSP_MWIRE_WAIT_ZERO,
1578 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1579};
1580
1581/**
1582 * pl022_setup - setup function registered to SPI host framework
1583 * @spi: spi device which is requesting setup
1584 *
1585 * This function is registered to the SPI framework for this SPI host
1586 * controller. If it is the first time when setup is called by this device,
1587 * this function will initialize the runtime state for this chip and save
1588 * the same in the device structure. Else it will update the runtime info
1589 * with the updated chip info. Nothing is really being written to the
1590 * controller hardware here, that is not done until the actual transfer
1591 * commence.
1592 */
1593static int pl022_setup(struct spi_device *spi)
1594{
1595 struct pl022_config_chip const *chip_info;
1596 struct pl022_config_chip chip_info_dt;
1597 struct chip_data *chip;
1598 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1599 int status = 0;
1600 struct pl022 *pl022 = spi_controller_get_devdata(spi->controller);
1601 unsigned int bits = spi->bits_per_word;
1602 u32 tmp;
1603 struct device_node *np = spi->dev.of_node;
1604
1605 if (!spi->max_speed_hz)
1606 return -EINVAL;
1607
1608 /* Get controller_state if one is supplied */
1609 chip = spi_get_ctldata(spi);
1610
1611 if (chip == NULL) {
1612 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1613 if (!chip)
1614 return -ENOMEM;
1615 dev_dbg(&spi->dev,
1616 "allocated memory for controller's runtime state\n");
1617 }
1618
1619 /* Get controller data if one is supplied */
1620 chip_info = spi->controller_data;
1621
1622 if (chip_info == NULL) {
1623 if (np) {
1624 chip_info_dt = pl022_default_chip_info;
1625
1626 chip_info_dt.hierarchy = SSP_MASTER;
1627 of_property_read_u32(np, "pl022,interface",
1628 &chip_info_dt.iface);
1629 of_property_read_u32(np, "pl022,com-mode",
1630 &chip_info_dt.com_mode);
1631 of_property_read_u32(np, "pl022,rx-level-trig",
1632 &chip_info_dt.rx_lev_trig);
1633 of_property_read_u32(np, "pl022,tx-level-trig",
1634 &chip_info_dt.tx_lev_trig);
1635 of_property_read_u32(np, "pl022,ctrl-len",
1636 &chip_info_dt.ctrl_len);
1637 of_property_read_u32(np, "pl022,wait-state",
1638 &chip_info_dt.wait_state);
1639 of_property_read_u32(np, "pl022,duplex",
1640 &chip_info_dt.duplex);
1641
1642 chip_info = &chip_info_dt;
1643 } else {
1644 chip_info = &pl022_default_chip_info;
1645 /* spi_board_info.controller_data not is supplied */
1646 dev_dbg(&spi->dev,
1647 "using default controller_data settings\n");
1648 }
1649 } else
1650 dev_dbg(&spi->dev,
1651 "using user supplied controller_data settings\n");
1652
1653 /*
1654 * We can override with custom divisors, else we use the board
1655 * frequency setting
1656 */
1657 if ((0 == chip_info->clk_freq.cpsdvsr)
1658 && (0 == chip_info->clk_freq.scr)) {
1659 status = calculate_effective_freq(pl022,
1660 spi->max_speed_hz,
1661 &clk_freq);
1662 if (status < 0)
1663 goto err_config_params;
1664 } else {
1665 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1666 if ((clk_freq.cpsdvsr % 2) != 0)
1667 clk_freq.cpsdvsr =
1668 clk_freq.cpsdvsr - 1;
1669 }
1670 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1671 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1672 status = -EINVAL;
1673 dev_err(&spi->dev,
1674 "cpsdvsr is configured incorrectly\n");
1675 goto err_config_params;
1676 }
1677
1678 status = verify_controller_parameters(pl022, chip_info);
1679 if (status) {
1680 dev_err(&spi->dev, "controller data is incorrect");
1681 goto err_config_params;
1682 }
1683
1684 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1685 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1686
1687 /* Now set controller state based on controller data */
1688 chip->xfer_type = chip_info->com_mode;
1689
1690 /* Check bits per word with vendor specific range */
1691 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1692 status = -ENOTSUPP;
1693 dev_err(&spi->dev, "illegal data size for this controller!\n");
1694 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1695 pl022->vendor->max_bpw);
1696 goto err_config_params;
1697 } else if (bits <= 8) {
1698 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1699 chip->n_bytes = 1;
1700 chip->read = READING_U8;
1701 chip->write = WRITING_U8;
1702 } else if (bits <= 16) {
1703 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1704 chip->n_bytes = 2;
1705 chip->read = READING_U16;
1706 chip->write = WRITING_U16;
1707 } else {
1708 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1709 chip->n_bytes = 4;
1710 chip->read = READING_U32;
1711 chip->write = WRITING_U32;
1712 }
1713
1714 /* Now Initialize all register settings required for this chip */
1715 chip->cr0 = 0;
1716 chip->cr1 = 0;
1717 chip->dmacr = 0;
1718 chip->cpsr = 0;
1719 if ((chip_info->com_mode == DMA_TRANSFER)
1720 && ((pl022->host_info)->enable_dma)) {
1721 chip->enable_dma = true;
1722 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1723 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1724 SSP_DMACR_MASK_RXDMAE, 0);
1725 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1726 SSP_DMACR_MASK_TXDMAE, 1);
1727 } else {
1728 chip->enable_dma = false;
1729 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1730 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1731 SSP_DMACR_MASK_RXDMAE, 0);
1732 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1733 SSP_DMACR_MASK_TXDMAE, 1);
1734 }
1735
1736 chip->cpsr = clk_freq.cpsdvsr;
1737
1738 /* Special setup for the ST micro extended control registers */
1739 if (pl022->vendor->extended_cr) {
1740 u32 etx;
1741
1742 if (pl022->vendor->pl023) {
1743 /* These bits are only in the PL023 */
1744 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1745 SSP_CR1_MASK_FBCLKDEL_ST, 13);
1746 } else {
1747 /* These bits are in the PL022 but not PL023 */
1748 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1749 SSP_CR0_MASK_HALFDUP_ST, 5);
1750 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1751 SSP_CR0_MASK_CSS_ST, 16);
1752 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1753 SSP_CR0_MASK_FRF_ST, 21);
1754 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1755 SSP_CR1_MASK_MWAIT_ST, 6);
1756 }
1757 SSP_WRITE_BITS(chip->cr0, bits - 1,
1758 SSP_CR0_MASK_DSS_ST, 0);
1759
1760 if (spi->mode & SPI_LSB_FIRST) {
1761 tmp = SSP_RX_LSB;
1762 etx = SSP_TX_LSB;
1763 } else {
1764 tmp = SSP_RX_MSB;
1765 etx = SSP_TX_MSB;
1766 }
1767 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
1768 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
1769 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
1770 SSP_CR1_MASK_RXIFLSEL_ST, 7);
1771 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
1772 SSP_CR1_MASK_TXIFLSEL_ST, 10);
1773 } else {
1774 SSP_WRITE_BITS(chip->cr0, bits - 1,
1775 SSP_CR0_MASK_DSS, 0);
1776 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1777 SSP_CR0_MASK_FRF, 4);
1778 }
1779
1780 /* Stuff that is common for all versions */
1781 if (spi->mode & SPI_CPOL)
1782 tmp = SSP_CLK_POL_IDLE_HIGH;
1783 else
1784 tmp = SSP_CLK_POL_IDLE_LOW;
1785 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
1786
1787 if (spi->mode & SPI_CPHA)
1788 tmp = SSP_CLK_SECOND_EDGE;
1789 else
1790 tmp = SSP_CLK_FIRST_EDGE;
1791 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
1792
1793 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
1794 /* Loopback is available on all versions except PL023 */
1795 if (pl022->vendor->loopback) {
1796 if (spi->mode & SPI_LOOP)
1797 tmp = LOOPBACK_ENABLED;
1798 else
1799 tmp = LOOPBACK_DISABLED;
1800 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
1801 }
1802 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
1803 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
1804 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
1805 3);
1806
1807 /* Save controller_state */
1808 spi_set_ctldata(spi, chip);
1809 return status;
1810 err_config_params:
1811 spi_set_ctldata(spi, NULL);
1812 kfree(chip);
1813 return status;
1814}
1815
1816/**
1817 * pl022_cleanup - cleanup function registered to SPI host framework
1818 * @spi: spi device which is requesting cleanup
1819 *
1820 * This function is registered to the SPI framework for this SPI host
1821 * controller. It will free the runtime state of chip.
1822 */
1823static void pl022_cleanup(struct spi_device *spi)
1824{
1825 struct chip_data *chip = spi_get_ctldata(spi);
1826
1827 spi_set_ctldata(spi, NULL);
1828 kfree(chip);
1829}
1830
1831static struct pl022_ssp_controller *
1832pl022_platform_data_dt_get(struct device *dev)
1833{
1834 struct device_node *np = dev->of_node;
1835 struct pl022_ssp_controller *pd;
1836
1837 if (!np) {
1838 dev_err(dev, "no dt node defined\n");
1839 return NULL;
1840 }
1841
1842 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
1843 if (!pd)
1844 return NULL;
1845
1846 pd->bus_id = -1;
1847 of_property_read_u32(np, "pl022,autosuspend-delay",
1848 &pd->autosuspend_delay);
1849 pd->rt = of_property_read_bool(np, "pl022,rt");
1850
1851 return pd;
1852}
1853
1854static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
1855{
1856 struct device *dev = &adev->dev;
1857 struct pl022_ssp_controller *platform_info =
1858 dev_get_platdata(&adev->dev);
1859 struct spi_controller *host;
1860 struct pl022 *pl022 = NULL; /*Data for this driver */
1861 int status = 0;
1862
1863 dev_info(&adev->dev,
1864 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
1865 if (!platform_info && IS_ENABLED(CONFIG_OF))
1866 platform_info = pl022_platform_data_dt_get(dev);
1867
1868 if (!platform_info) {
1869 dev_err(dev, "probe: no platform data defined\n");
1870 return -ENODEV;
1871 }
1872
1873 /* Allocate host with space for data */
1874 host = spi_alloc_host(dev, sizeof(struct pl022));
1875 if (host == NULL) {
1876 dev_err(&adev->dev, "probe - cannot alloc SPI host\n");
1877 return -ENOMEM;
1878 }
1879
1880 pl022 = spi_controller_get_devdata(host);
1881 pl022->host = host;
1882 pl022->host_info = platform_info;
1883 pl022->adev = adev;
1884 pl022->vendor = id->data;
1885
1886 /*
1887 * Bus Number Which has been Assigned to this SSP controller
1888 * on this board
1889 */
1890 host->bus_num = platform_info->bus_id;
1891 host->cleanup = pl022_cleanup;
1892 host->setup = pl022_setup;
1893 host->auto_runtime_pm = true;
1894 host->transfer_one = pl022_transfer_one;
1895 host->set_cs = pl022_cs_control;
1896 host->handle_err = pl022_handle_err;
1897 host->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
1898 host->rt = platform_info->rt;
1899 host->dev.of_node = dev->of_node;
1900 host->use_gpio_descriptors = true;
1901
1902 /*
1903 * Supports mode 0-3, loopback, and active low CS. Transfers are
1904 * always MS bit first on the original pl022.
1905 */
1906 host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1907 if (pl022->vendor->extended_cr)
1908 host->mode_bits |= SPI_LSB_FIRST;
1909
1910 dev_dbg(&adev->dev, "BUSNO: %d\n", host->bus_num);
1911
1912 status = amba_request_regions(adev, NULL);
1913 if (status)
1914 goto err_no_ioregion;
1915
1916 pl022->phybase = adev->res.start;
1917 pl022->virtbase = devm_ioremap(dev, adev->res.start,
1918 resource_size(&adev->res));
1919 if (pl022->virtbase == NULL) {
1920 status = -ENOMEM;
1921 goto err_no_ioremap;
1922 }
1923 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
1924 &adev->res.start, pl022->virtbase);
1925
1926 pl022->clk = devm_clk_get_enabled(&adev->dev, NULL);
1927 if (IS_ERR(pl022->clk)) {
1928 status = PTR_ERR(pl022->clk);
1929 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
1930 goto err_no_clk;
1931 }
1932
1933 /* Disable SSP */
1934 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
1935 SSP_CR1(pl022->virtbase));
1936 load_ssp_default_config(pl022);
1937
1938 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
1939 0, "pl022", pl022);
1940 if (status < 0) {
1941 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
1942 goto err_no_irq;
1943 }
1944
1945 /* Get DMA channels, try autoconfiguration first */
1946 status = pl022_dma_autoprobe(pl022);
1947 if (status == -EPROBE_DEFER) {
1948 dev_dbg(dev, "deferring probe to get DMA channel\n");
1949 goto err_no_irq;
1950 }
1951
1952 /* If that failed, use channels from platform_info */
1953 if (status == 0)
1954 platform_info->enable_dma = 1;
1955 else if (platform_info->enable_dma) {
1956 status = pl022_dma_probe(pl022);
1957 if (status != 0)
1958 platform_info->enable_dma = 0;
1959 }
1960
1961 /* Register with the SPI framework */
1962 amba_set_drvdata(adev, pl022);
1963 status = devm_spi_register_controller(&adev->dev, host);
1964 if (status != 0) {
1965 dev_err_probe(&adev->dev, status,
1966 "problem registering spi host\n");
1967 goto err_spi_register;
1968 }
1969 dev_dbg(dev, "probe succeeded\n");
1970
1971 /* let runtime pm put suspend */
1972 if (platform_info->autosuspend_delay > 0) {
1973 dev_info(&adev->dev,
1974 "will use autosuspend for runtime pm, delay %dms\n",
1975 platform_info->autosuspend_delay);
1976 pm_runtime_set_autosuspend_delay(dev,
1977 platform_info->autosuspend_delay);
1978 pm_runtime_use_autosuspend(dev);
1979 }
1980 pm_runtime_put(dev);
1981
1982 return 0;
1983
1984 err_spi_register:
1985 if (platform_info->enable_dma)
1986 pl022_dma_remove(pl022);
1987 err_no_irq:
1988 err_no_clk:
1989 err_no_ioremap:
1990 amba_release_regions(adev);
1991 err_no_ioregion:
1992 spi_controller_put(host);
1993 return status;
1994}
1995
1996static void
1997pl022_remove(struct amba_device *adev)
1998{
1999 struct pl022 *pl022 = amba_get_drvdata(adev);
2000
2001 if (!pl022)
2002 return;
2003
2004 /*
2005 * undo pm_runtime_put() in probe. I assume that we're not
2006 * accessing the primecell here.
2007 */
2008 pm_runtime_get_noresume(&adev->dev);
2009
2010 load_ssp_default_config(pl022);
2011 if (pl022->host_info->enable_dma)
2012 pl022_dma_remove(pl022);
2013
2014 amba_release_regions(adev);
2015}
2016
2017#ifdef CONFIG_PM_SLEEP
2018static int pl022_suspend(struct device *dev)
2019{
2020 struct pl022 *pl022 = dev_get_drvdata(dev);
2021 int ret;
2022
2023 ret = spi_controller_suspend(pl022->host);
2024 if (ret)
2025 return ret;
2026
2027 ret = pm_runtime_force_suspend(dev);
2028 if (ret) {
2029 spi_controller_resume(pl022->host);
2030 return ret;
2031 }
2032
2033 pinctrl_pm_select_sleep_state(dev);
2034
2035 dev_dbg(dev, "suspended\n");
2036 return 0;
2037}
2038
2039static int pl022_resume(struct device *dev)
2040{
2041 struct pl022 *pl022 = dev_get_drvdata(dev);
2042 int ret;
2043
2044 ret = pm_runtime_force_resume(dev);
2045 if (ret)
2046 dev_err(dev, "problem resuming\n");
2047
2048 /* Start the queue running */
2049 ret = spi_controller_resume(pl022->host);
2050 if (!ret)
2051 dev_dbg(dev, "resumed\n");
2052
2053 return ret;
2054}
2055#endif
2056
2057#ifdef CONFIG_PM
2058static int pl022_runtime_suspend(struct device *dev)
2059{
2060 struct pl022 *pl022 = dev_get_drvdata(dev);
2061
2062 clk_disable_unprepare(pl022->clk);
2063 pinctrl_pm_select_idle_state(dev);
2064
2065 return 0;
2066}
2067
2068static int pl022_runtime_resume(struct device *dev)
2069{
2070 struct pl022 *pl022 = dev_get_drvdata(dev);
2071
2072 pinctrl_pm_select_default_state(dev);
2073 clk_prepare_enable(pl022->clk);
2074
2075 return 0;
2076}
2077#endif
2078
2079static const struct dev_pm_ops pl022_dev_pm_ops = {
2080 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2081 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2082};
2083
2084static struct vendor_data vendor_arm = {
2085 .fifodepth = 8,
2086 .max_bpw = 16,
2087 .unidir = false,
2088 .extended_cr = false,
2089 .pl023 = false,
2090 .loopback = true,
2091 .internal_cs_ctrl = false,
2092};
2093
2094static struct vendor_data vendor_st = {
2095 .fifodepth = 32,
2096 .max_bpw = 32,
2097 .unidir = false,
2098 .extended_cr = true,
2099 .pl023 = false,
2100 .loopback = true,
2101 .internal_cs_ctrl = false,
2102};
2103
2104static struct vendor_data vendor_st_pl023 = {
2105 .fifodepth = 32,
2106 .max_bpw = 32,
2107 .unidir = false,
2108 .extended_cr = true,
2109 .pl023 = true,
2110 .loopback = false,
2111 .internal_cs_ctrl = false,
2112};
2113
2114static struct vendor_data vendor_lsi = {
2115 .fifodepth = 8,
2116 .max_bpw = 16,
2117 .unidir = false,
2118 .extended_cr = false,
2119 .pl023 = false,
2120 .loopback = true,
2121 .internal_cs_ctrl = true,
2122};
2123
2124static const struct amba_id pl022_ids[] = {
2125 {
2126 /*
2127 * ARM PL022 variant, this has a 16bit wide
2128 * and 8 locations deep TX/RX FIFO
2129 */
2130 .id = 0x00041022,
2131 .mask = 0x000fffff,
2132 .data = &vendor_arm,
2133 },
2134 {
2135 /*
2136 * ST Micro derivative, this has 32bit wide
2137 * and 32 locations deep TX/RX FIFO
2138 */
2139 .id = 0x01080022,
2140 .mask = 0xffffffff,
2141 .data = &vendor_st,
2142 },
2143 {
2144 /*
2145 * ST-Ericsson derivative "PL023" (this is not
2146 * an official ARM number), this is a PL022 SSP block
2147 * stripped to SPI mode only, it has 32bit wide
2148 * and 32 locations deep TX/RX FIFO but no extended
2149 * CR0/CR1 register
2150 */
2151 .id = 0x00080023,
2152 .mask = 0xffffffff,
2153 .data = &vendor_st_pl023,
2154 },
2155 {
2156 /*
2157 * PL022 variant that has a chip select control register whih
2158 * allows control of 5 output signals nCS[0:4].
2159 */
2160 .id = 0x000b6022,
2161 .mask = 0x000fffff,
2162 .data = &vendor_lsi,
2163 },
2164 { 0, 0 },
2165};
2166
2167MODULE_DEVICE_TABLE(amba, pl022_ids);
2168
2169static struct amba_driver pl022_driver = {
2170 .drv = {
2171 .name = "ssp-pl022",
2172 .pm = &pl022_dev_pm_ops,
2173 },
2174 .id_table = pl022_ids,
2175 .probe = pl022_probe,
2176 .remove = pl022_remove,
2177};
2178
2179static int __init pl022_init(void)
2180{
2181 return amba_driver_register(&pl022_driver);
2182}
2183subsys_initcall(pl022_init);
2184
2185static void __exit pl022_exit(void)
2186{
2187 amba_driver_unregister(&pl022_driver);
2188}
2189module_exit(pl022_exit);
2190
2191MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2192MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2193MODULE_LICENSE("GPL");