1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Freescale SPI controller driver cpm functions.
4 *
5 * Maintainer: Kumar Gala
6 *
7 * Copyright (C) 2006 Polycom, Inc.
8 * Copyright 2010 Freescale Semiconductor, Inc.
9 *
10 * CPM SPI and QE buffer descriptors mode support:
11 * Copyright (c) 2009 MontaVista Software, Inc.
12 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
13 */
14#include <asm/cpm.h>
15#include <soc/fsl/qe/qe.h>
16#include <linux/dma-mapping.h>
17#include <linux/fsl_devices.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/of_address.h>
21#include <linux/spi/spi.h>
22#include <linux/types.h>
23#include <linux/platform_device.h>
24#include <linux/byteorder/generic.h>
25
26#include "spi-fsl-cpm.h"
27#include "spi-fsl-lib.h"
28#include "spi-fsl-spi.h"
29
30/* CPM1 and CPM2 are mutually exclusive. */
31#ifdef CONFIG_CPM1
32#include <asm/cpm1.h>
33#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0)
34#else
35#include <asm/cpm2.h>
36#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0)
37#endif
38
39#define SPIE_TXB 0x00000200 /* Last char is written to tx fifo */
40#define SPIE_RXB 0x00000100 /* Last char is written to rx buf */
41
42/* SPCOM register values */
43#define SPCOM_STR (1 << 23) /* Start transmit */
44
45#define SPI_PRAM_SIZE 0x100
46#define SPI_MRBLR ((unsigned int)PAGE_SIZE)
47
48static void *fsl_dummy_rx;
49static DEFINE_MUTEX(fsl_dummy_rx_lock);
50static int fsl_dummy_rx_refcnt;
51
52void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi)
53{
54 if (mspi->flags & SPI_QE) {
55 qe_issue_cmd(QE_INIT_TX_RX, device: mspi->subblock,
56 QE_CR_PROTOCOL_UNSPECIFIED, cmd_input: 0);
57 } else {
58 if (mspi->flags & SPI_CPM1) {
59 iowrite32be(0, &mspi->pram->rstate);
60 iowrite16be(ioread16be(&mspi->pram->rbase),
61 &mspi->pram->rbptr);
62 iowrite32be(0, &mspi->pram->tstate);
63 iowrite16be(ioread16be(&mspi->pram->tbase),
64 &mspi->pram->tbptr);
65 } else {
66 cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX);
67 }
68 }
69}
70EXPORT_SYMBOL_GPL(fsl_spi_cpm_reinit_txrx);
71
72static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi)
73{
74 struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd;
75 struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd;
76 unsigned int xfer_len = min(mspi->count, SPI_MRBLR);
77 unsigned int xfer_ofs;
78 struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
79
80 xfer_ofs = mspi->xfer_in_progress->len - mspi->count;
81
82 if (mspi->rx_dma == mspi->dma_dummy_rx)
83 iowrite32be(mspi->rx_dma, &rx_bd->cbd_bufaddr);
84 else
85 iowrite32be(mspi->rx_dma + xfer_ofs, &rx_bd->cbd_bufaddr);
86 iowrite16be(0, &rx_bd->cbd_datlen);
87 iowrite16be(BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP, &rx_bd->cbd_sc);
88
89 if (mspi->tx_dma == mspi->dma_dummy_tx)
90 iowrite32be(mspi->tx_dma, &tx_bd->cbd_bufaddr);
91 else
92 iowrite32be(mspi->tx_dma + xfer_ofs, &tx_bd->cbd_bufaddr);
93 iowrite16be(xfer_len, &tx_bd->cbd_datlen);
94 iowrite16be(BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP | BD_SC_LAST,
95 &tx_bd->cbd_sc);
96
97 /* start transfer */
98 mpc8xxx_spi_write_reg(reg: &reg_base->command, SPCOM_STR);
99}
100
101int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi,
102 struct spi_transfer *t, bool is_dma_mapped)
103{
104 struct device *dev = mspi->dev;
105 struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
106
107 if (is_dma_mapped) {
108 mspi->map_tx_dma = 0;
109 mspi->map_rx_dma = 0;
110 } else {
111 mspi->map_tx_dma = 1;
112 mspi->map_rx_dma = 1;
113 }
114
115 if (!t->tx_buf) {
116 mspi->tx_dma = mspi->dma_dummy_tx;
117 mspi->map_tx_dma = 0;
118 }
119
120 if (!t->rx_buf) {
121 mspi->rx_dma = mspi->dma_dummy_rx;
122 mspi->map_rx_dma = 0;
123 }
124 if (t->bits_per_word == 16 && t->tx_buf) {
125 const u16 *src = t->tx_buf;
126 __le16 *dst;
127 int i;
128
129 dst = kmalloc(size: t->len, GFP_KERNEL);
130 if (!dst)
131 return -ENOMEM;
132
133 for (i = 0; i < t->len >> 1; i++)
134 dst[i] = cpu_to_le16p(p: src + i);
135
136 mspi->tx = dst;
137 mspi->map_tx_dma = 1;
138 }
139
140 if (mspi->map_tx_dma) {
141 void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */
142
143 mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len,
144 DMA_TO_DEVICE);
145 if (dma_mapping_error(dev, dma_addr: mspi->tx_dma)) {
146 dev_err(dev, "unable to map tx dma\n");
147 return -ENOMEM;
148 }
149 } else if (t->tx_buf) {
150 mspi->tx_dma = t->tx_dma;
151 }
152
153 if (mspi->map_rx_dma) {
154 mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len,
155 DMA_FROM_DEVICE);
156 if (dma_mapping_error(dev, dma_addr: mspi->rx_dma)) {
157 dev_err(dev, "unable to map rx dma\n");
158 goto err_rx_dma;
159 }
160 } else if (t->rx_buf) {
161 mspi->rx_dma = t->rx_dma;
162 }
163
164 /* enable rx ints */
165 mpc8xxx_spi_write_reg(reg: &reg_base->mask, SPIE_RXB);
166
167 mspi->xfer_in_progress = t;
168 mspi->count = t->len;
169
170 /* start CPM transfers */
171 fsl_spi_cpm_bufs_start(mspi);
172
173 return 0;
174
175err_rx_dma:
176 if (mspi->map_tx_dma)
177 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
178 return -ENOMEM;
179}
180EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs);
181
182void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi)
183{
184 struct device *dev = mspi->dev;
185 struct spi_transfer *t = mspi->xfer_in_progress;
186
187 if (mspi->map_tx_dma)
188 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
189 if (mspi->map_rx_dma)
190 dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE);
191 mspi->xfer_in_progress = NULL;
192
193 if (t->bits_per_word == 16 && t->rx_buf) {
194 int i;
195
196 for (i = 0; i < t->len; i += 2)
197 le16_to_cpus(t->rx_buf + i);
198 }
199}
200EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs_complete);
201
202void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events)
203{
204 u16 len;
205 struct fsl_spi_reg __iomem *reg_base = mspi->reg_base;
206
207 dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__,
208 ioread16be(&mspi->rx_bd->cbd_datlen), mspi->count);
209
210 len = ioread16be(&mspi->rx_bd->cbd_datlen);
211 if (len > mspi->count) {
212 WARN_ON(1);
213 len = mspi->count;
214 }
215
216 /* Clear the events */
217 mpc8xxx_spi_write_reg(reg: &reg_base->event, val: events);
218
219 mspi->count -= len;
220 if (mspi->count)
221 fsl_spi_cpm_bufs_start(mspi);
222 else
223 complete(&mspi->done);
224}
225EXPORT_SYMBOL_GPL(fsl_spi_cpm_irq);
226
227static void *fsl_spi_alloc_dummy_rx(void)
228{
229 mutex_lock(&fsl_dummy_rx_lock);
230
231 if (!fsl_dummy_rx)
232 fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL);
233 if (fsl_dummy_rx)
234 fsl_dummy_rx_refcnt++;
235
236 mutex_unlock(lock: &fsl_dummy_rx_lock);
237
238 return fsl_dummy_rx;
239}
240
241static void fsl_spi_free_dummy_rx(void)
242{
243 mutex_lock(&fsl_dummy_rx_lock);
244
245 switch (fsl_dummy_rx_refcnt) {
246 case 0:
247 WARN_ON(1);
248 break;
249 case 1:
250 kfree(objp: fsl_dummy_rx);
251 fsl_dummy_rx = NULL;
252 fallthrough;
253 default:
254 fsl_dummy_rx_refcnt--;
255 break;
256 }
257
258 mutex_unlock(lock: &fsl_dummy_rx_lock);
259}
260
261static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
262{
263 struct device *dev = mspi->dev;
264 struct device_node *np = dev->of_node;
265 const u32 *iprop;
266 int size;
267 void __iomem *spi_base;
268 unsigned long pram_ofs = -ENOMEM;
269
270 /* Can't use of_address_to_resource(), QE muram isn't at 0. */
271 iprop = of_get_property(node: np, name: "reg", lenp: &size);
272
273 /* QE with a fixed pram location? */
274 if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4)
275 return cpm_muram_alloc_fixed(offset: iprop[2], SPI_PRAM_SIZE);
276
277 /* QE but with a dynamic pram location? */
278 if (mspi->flags & SPI_QE) {
279 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, align: 64);
280 qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, device: mspi->subblock,
281 QE_CR_PROTOCOL_UNSPECIFIED, cmd_input: pram_ofs);
282 return pram_ofs;
283 }
284
285 spi_base = of_iomap(node: np, index: 1);
286 if (spi_base == NULL)
287 return -EINVAL;
288
289 if (mspi->flags & SPI_CPM2) {
290 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, align: 64);
291 out_be16(spi_base, pram_ofs);
292 }
293
294 iounmap(addr: spi_base);
295 return pram_ofs;
296}
297
298int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi)
299{
300 struct device *dev = mspi->dev;
301 struct device_node *np = dev->of_node;
302 const u32 *iprop;
303 int size;
304 unsigned long bds_ofs;
305
306 if (!(mspi->flags & SPI_CPM_MODE))
307 return 0;
308
309 if (!fsl_spi_alloc_dummy_rx())
310 return -ENOMEM;
311
312 if (mspi->flags & SPI_QE) {
313 iprop = of_get_property(node: np, name: "cell-index", lenp: &size);
314 if (iprop && size == sizeof(*iprop))
315 mspi->subblock = *iprop;
316
317 switch (mspi->subblock) {
318 default:
319 dev_warn(dev, "cell-index unspecified, assuming SPI1\n");
320 fallthrough;
321 case 0:
322 mspi->subblock = QE_CR_SUBBLOCK_SPI1;
323 break;
324 case 1:
325 mspi->subblock = QE_CR_SUBBLOCK_SPI2;
326 break;
327 }
328 }
329
330 if (mspi->flags & SPI_CPM1) {
331 void __iomem *pram;
332
333 pram = devm_platform_ioremap_resource(to_platform_device(dev),
334 index: 1);
335 if (IS_ERR(ptr: pram))
336 mspi->pram = NULL;
337 else
338 mspi->pram = pram;
339 } else {
340 unsigned long pram_ofs = fsl_spi_cpm_get_pram(mspi);
341
342 if (IS_ERR_VALUE(pram_ofs))
343 mspi->pram = NULL;
344 else
345 mspi->pram = cpm_muram_addr(offset: pram_ofs);
346 }
347 if (mspi->pram == NULL) {
348 dev_err(dev, "can't allocate spi parameter ram\n");
349 goto err_pram;
350 }
351
352 bds_ofs = cpm_muram_alloc(size: sizeof(*mspi->tx_bd) +
353 sizeof(*mspi->rx_bd), align: 8);
354 if (IS_ERR_VALUE(bds_ofs)) {
355 dev_err(dev, "can't allocate bds\n");
356 goto err_bds;
357 }
358
359 mspi->dma_dummy_tx = dma_map_single(dev, ZERO_PAGE(0), PAGE_SIZE,
360 DMA_TO_DEVICE);
361 if (dma_mapping_error(dev, dma_addr: mspi->dma_dummy_tx)) {
362 dev_err(dev, "unable to map dummy tx buffer\n");
363 goto err_dummy_tx;
364 }
365
366 mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR,
367 DMA_FROM_DEVICE);
368 if (dma_mapping_error(dev, dma_addr: mspi->dma_dummy_rx)) {
369 dev_err(dev, "unable to map dummy rx buffer\n");
370 goto err_dummy_rx;
371 }
372
373 mspi->tx_bd = cpm_muram_addr(offset: bds_ofs);
374 mspi->rx_bd = cpm_muram_addr(offset: bds_ofs + sizeof(*mspi->tx_bd));
375
376 /* Initialize parameter ram. */
377 iowrite16be(cpm_muram_offset(addr: mspi->tx_bd), &mspi->pram->tbase);
378 iowrite16be(cpm_muram_offset(addr: mspi->rx_bd), &mspi->pram->rbase);
379 iowrite8(CPMFCR_EB | CPMFCR_GBL, &mspi->pram->tfcr);
380 iowrite8(CPMFCR_EB | CPMFCR_GBL, &mspi->pram->rfcr);
381 iowrite16be(SPI_MRBLR, &mspi->pram->mrblr);
382 iowrite32be(0, &mspi->pram->rstate);
383 iowrite32be(0, &mspi->pram->rdp);
384 iowrite16be(0, &mspi->pram->rbptr);
385 iowrite16be(0, &mspi->pram->rbc);
386 iowrite32be(0, &mspi->pram->rxtmp);
387 iowrite32be(0, &mspi->pram->tstate);
388 iowrite32be(0, &mspi->pram->tdp);
389 iowrite16be(0, &mspi->pram->tbptr);
390 iowrite16be(0, &mspi->pram->tbc);
391 iowrite32be(0, &mspi->pram->txtmp);
392
393 return 0;
394
395err_dummy_rx:
396 dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
397err_dummy_tx:
398 cpm_muram_free(offset: bds_ofs);
399err_bds:
400 if (!(mspi->flags & SPI_CPM1))
401 cpm_muram_free(offset: cpm_muram_offset(addr: mspi->pram));
402err_pram:
403 fsl_spi_free_dummy_rx();
404 return -ENOMEM;
405}
406EXPORT_SYMBOL_GPL(fsl_spi_cpm_init);
407
408void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi)
409{
410 struct device *dev = mspi->dev;
411
412 if (!(mspi->flags & SPI_CPM_MODE))
413 return;
414
415 dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE);
416 dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
417 cpm_muram_free(offset: cpm_muram_offset(addr: mspi->tx_bd));
418 if (!(mspi->flags & SPI_CPM1))
419 cpm_muram_free(offset: cpm_muram_offset(addr: mspi->pram));
420 fsl_spi_free_dummy_rx();
421}
422EXPORT_SYMBOL_GPL(fsl_spi_cpm_free);
423
424MODULE_LICENSE("GPL");
425

source code of linux/drivers/spi/spi-fsl-cpm.c