1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * eSPI controller driver.
4 *
5 * Copyright 2010-2011 Freescale Semiconductor, Inc.
6 * Author: Mingkai Hu (Mingkai.hu@freescale.com)
7 */
8
9 #include <common.h>
10
11 #include <malloc.h>
12 #include <spi.h>
13 #include <asm/immap_85xx.h>
14
15 struct fsl_spi_slave {
16 struct spi_slave slave;
17 ccsr_espi_t *espi;
18 unsigned int div16;
19 unsigned int pm;
20 int tx_timeout;
21 unsigned int mode;
22 size_t cmd_len;
23 u8 cmd_buf[16];
24 size_t data_len;
25 unsigned int max_transfer_length;
26 };
27
28 #define to_fsl_spi_slave(s) container_of(s, struct fsl_spi_slave, slave)
29 #define US_PER_SECOND 1000000UL
30
31 #define ESPI_MAX_CS_NUM 4
32 #define ESPI_FIFO_WIDTH_BIT 32
33
34 #define ESPI_EV_RNE BIT(9)
35 #define ESPI_EV_TNF BIT(8)
36 #define ESPI_EV_DON BIT(14)
37 #define ESPI_EV_TXE BIT(15)
38 #define ESPI_EV_RFCNT_SHIFT 24
39 #define ESPI_EV_RFCNT_MASK (0x3f << ESPI_EV_RFCNT_SHIFT)
40
41 #define ESPI_MODE_EN BIT(31) /* Enable interface */
42 #define ESPI_MODE_TXTHR(x) ((x) << 8) /* Tx FIFO threshold */
43 #define ESPI_MODE_RXTHR(x) ((x) << 0) /* Rx FIFO threshold */
44
45 #define ESPI_COM_CS(x) ((x) << 30)
46 #define ESPI_COM_TRANLEN(x) ((x) << 0)
47
48 #define ESPI_CSMODE_CI_INACTIVEHIGH BIT(31)
49 #define ESPI_CSMODE_CP_BEGIN_EDGCLK BIT(30)
50 #define ESPI_CSMODE_REV_MSB_FIRST BIT(29)
51 #define ESPI_CSMODE_DIV16 BIT(28)
52 #define ESPI_CSMODE_PM(x) ((x) << 24)
53 #define ESPI_CSMODE_POL_ASSERTED_LOW BIT(20)
54 #define ESPI_CSMODE_LEN(x) ((x) << 16)
55 #define ESPI_CSMODE_CSBEF(x) ((x) << 12)
56 #define ESPI_CSMODE_CSAFT(x) ((x) << 8)
57 #define ESPI_CSMODE_CSCG(x) ((x) << 3)
58
59 #define ESPI_CSMODE_INIT_VAL (ESPI_CSMODE_POL_ASSERTED_LOW | \
60 ESPI_CSMODE_CSBEF(0) | ESPI_CSMODE_CSAFT(0) | \
61 ESPI_CSMODE_CSCG(1))
62
63 #define ESPI_MAX_DATA_TRANSFER_LEN 0xFFF0
64
spi_setup_slave(unsigned int bus,unsigned int cs,unsigned int max_hz,unsigned int mode)65 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
66 unsigned int max_hz, unsigned int mode)
67 {
68 struct fsl_spi_slave *fsl;
69 sys_info_t sysinfo;
70 unsigned long spibrg = 0;
71 unsigned long spi_freq = 0;
72 unsigned char pm = 0;
73
74 if (!spi_cs_is_valid(bus, cs))
75 return NULL;
76
77 fsl = spi_alloc_slave(struct fsl_spi_slave, bus, cs);
78 if (!fsl)
79 return NULL;
80
81 fsl->espi = (void *)(CONFIG_SYS_MPC85xx_ESPI_ADDR);
82 fsl->mode = mode;
83 fsl->max_transfer_length = ESPI_MAX_DATA_TRANSFER_LEN;
84
85 /* Set eSPI BRG clock source */
86 get_sys_info(&sysinfo);
87 spibrg = sysinfo.freq_systembus / 2;
88 fsl->div16 = 0;
89 if ((spibrg / max_hz) > 32) {
90 fsl->div16 = ESPI_CSMODE_DIV16;
91 pm = spibrg / (max_hz * 16 * 2);
92 if (pm > 16) {
93 pm = 16;
94 debug("Requested speed is too low: %d Hz, %ld Hz "
95 "is used.\n", max_hz, spibrg / (32 * 16));
96 }
97 } else
98 pm = spibrg / (max_hz * 2);
99 if (pm)
100 pm--;
101 fsl->pm = pm;
102
103 if (fsl->div16)
104 spi_freq = spibrg / ((pm + 1) * 2 * 16);
105 else
106 spi_freq = spibrg / ((pm + 1) * 2);
107
108 /* set tx_timeout to 10 times of one espi FIFO entry go out */
109 fsl->tx_timeout = DIV_ROUND_UP((US_PER_SECOND * ESPI_FIFO_WIDTH_BIT
110 * 10), spi_freq);
111
112 return &fsl->slave;
113 }
114
spi_free_slave(struct spi_slave * slave)115 void spi_free_slave(struct spi_slave *slave)
116 {
117 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave);
118 free(fsl);
119 }
120
spi_claim_bus(struct spi_slave * slave)121 int spi_claim_bus(struct spi_slave *slave)
122 {
123 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave);
124 ccsr_espi_t *espi = fsl->espi;
125 unsigned char pm = fsl->pm;
126 unsigned int cs = slave->cs;
127 unsigned int mode = fsl->mode;
128 unsigned int div16 = fsl->div16;
129 int i;
130
131 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, cs);
132
133 /* Enable eSPI interface */
134 out_be32(&espi->mode, ESPI_MODE_RXTHR(3)
135 | ESPI_MODE_TXTHR(4) | ESPI_MODE_EN);
136
137 out_be32(&espi->event, 0xffffffff); /* Clear all eSPI events */
138 out_be32(&espi->mask, 0x00000000); /* Mask all eSPI interrupts */
139
140 /* Init CS mode interface */
141 for (i = 0; i < ESPI_MAX_CS_NUM; i++)
142 out_be32(&espi->csmode[i], ESPI_CSMODE_INIT_VAL);
143
144 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) &
145 ~(ESPI_CSMODE_PM(0xF) | ESPI_CSMODE_DIV16
146 | ESPI_CSMODE_CI_INACTIVEHIGH | ESPI_CSMODE_CP_BEGIN_EDGCLK
147 | ESPI_CSMODE_REV_MSB_FIRST | ESPI_CSMODE_LEN(0xF)));
148
149 /* Set eSPI BRG clock source */
150 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs])
151 | ESPI_CSMODE_PM(pm) | div16);
152
153 /* Set eSPI mode */
154 if (mode & SPI_CPHA)
155 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs])
156 | ESPI_CSMODE_CP_BEGIN_EDGCLK);
157 if (mode & SPI_CPOL)
158 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs])
159 | ESPI_CSMODE_CI_INACTIVEHIGH);
160
161 /* Character bit order: msb first */
162 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs])
163 | ESPI_CSMODE_REV_MSB_FIRST);
164
165 /* Character length in bits, between 0x3~0xf, i.e. 4bits~16bits */
166 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs])
167 | ESPI_CSMODE_LEN(7));
168
169 return 0;
170 }
171
spi_release_bus(struct spi_slave * slave)172 void spi_release_bus(struct spi_slave *slave)
173 {
174
175 }
176
fsl_espi_tx(struct fsl_spi_slave * fsl,const void * dout)177 static void fsl_espi_tx(struct fsl_spi_slave *fsl, const void *dout)
178 {
179 ccsr_espi_t *espi = fsl->espi;
180 unsigned int tmpdout, event;
181 int tmp_tx_timeout;
182
183 if (dout)
184 tmpdout = *(u32 *)dout;
185 else
186 tmpdout = 0;
187
188 out_be32(&espi->tx, tmpdout);
189 out_be32(&espi->event, ESPI_EV_TNF);
190 debug("***spi_xfer:...%08x written\n", tmpdout);
191
192 tmp_tx_timeout = fsl->tx_timeout;
193 /* Wait for eSPI transmit to go out */
194 while (tmp_tx_timeout--) {
195 event = in_be32(&espi->event);
196 if (event & ESPI_EV_DON || event & ESPI_EV_TXE) {
197 out_be32(&espi->event, ESPI_EV_TXE);
198 break;
199 }
200 udelay(1);
201 }
202
203 if (tmp_tx_timeout < 0)
204 debug("***spi_xfer:...Tx timeout! event = %08x\n", event);
205 }
206
fsl_espi_rx(struct fsl_spi_slave * fsl,void * din,unsigned int bytes)207 static int fsl_espi_rx(struct fsl_spi_slave *fsl, void *din, unsigned int bytes)
208 {
209 ccsr_espi_t *espi = fsl->espi;
210 unsigned int tmpdin, rx_times;
211 unsigned char *buf, *p_cursor;
212
213 if (bytes <= 0)
214 return 0;
215
216 rx_times = DIV_ROUND_UP(bytes, 4);
217 buf = (unsigned char *)malloc(4 * rx_times);
218 if (!buf) {
219 debug("SF: Failed to malloc memory.\n");
220 return -1;
221 }
222 p_cursor = buf;
223 while (rx_times--) {
224 tmpdin = in_be32(&espi->rx);
225 debug("***spi_xfer:...%08x readed\n", tmpdin);
226 *(u32 *)p_cursor = tmpdin;
227 p_cursor += 4;
228 }
229
230 if (din)
231 memcpy(din, buf, bytes);
232
233 free(buf);
234 out_be32(&espi->event, ESPI_EV_RNE);
235
236 return bytes;
237 }
238
spi_xfer(struct spi_slave * slave,unsigned int bitlen,const void * data_out,void * data_in,unsigned long flags)239 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *data_out,
240 void *data_in, unsigned long flags)
241 {
242 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave);
243 ccsr_espi_t *espi = fsl->espi;
244 unsigned int event, rx_bytes;
245 const void *dout = NULL;
246 void *din = NULL;
247 int len = 0;
248 int num_blks, num_chunks, max_tran_len, tran_len;
249 int num_bytes;
250 unsigned char *buffer = NULL;
251 size_t buf_len;
252 u8 *cmd_buf = fsl->cmd_buf;
253 size_t cmd_len = fsl->cmd_len;
254 size_t data_len = bitlen / 8;
255 size_t rx_offset = 0;
256 int rf_cnt;
257
258 max_tran_len = fsl->max_transfer_length;
259 switch (flags) {
260 case SPI_XFER_BEGIN:
261 cmd_len = fsl->cmd_len = data_len;
262 memcpy(cmd_buf, data_out, cmd_len);
263 return 0;
264 case 0:
265 case SPI_XFER_END:
266 if (bitlen == 0) {
267 spi_cs_deactivate(slave);
268 return 0;
269 }
270 buf_len = 2 * cmd_len + min(data_len, (size_t)max_tran_len);
271 len = cmd_len + data_len;
272 rx_offset = cmd_len;
273 buffer = (unsigned char *)malloc(buf_len);
274 if (!buffer) {
275 debug("SF: Failed to malloc memory.\n");
276 return 1;
277 }
278 memcpy(buffer, cmd_buf, cmd_len);
279 if (data_in == NULL)
280 memcpy(buffer + cmd_len, data_out, data_len);
281 break;
282 case SPI_XFER_BEGIN | SPI_XFER_END:
283 len = data_len;
284 buffer = (unsigned char *)malloc(len * 2);
285 if (!buffer) {
286 debug("SF: Failed to malloc memory.\n");
287 return 1;
288 }
289 memcpy(buffer, data_out, len);
290 rx_offset = len;
291 cmd_len = 0;
292 break;
293 }
294
295 debug("spi_xfer: data_out %08X(%p) data_in %08X(%p) len %u\n",
296 *(uint *)data_out, data_out, *(uint *)data_in, data_in, len);
297
298 num_chunks = DIV_ROUND_UP(data_len, max_tran_len);
299 while (num_chunks--) {
300 if (data_in)
301 din = buffer + rx_offset;
302 dout = buffer;
303 tran_len = min(data_len, (size_t)max_tran_len);
304 num_blks = DIV_ROUND_UP(tran_len + cmd_len, 4);
305 num_bytes = (tran_len + cmd_len) % 4;
306 fsl->data_len = tran_len + cmd_len;
307 spi_cs_activate(slave);
308
309 /* Clear all eSPI events */
310 out_be32(&espi->event , 0xffffffff);
311 /* handle data in 32-bit chunks */
312 while (num_blks) {
313 event = in_be32(&espi->event);
314 if (event & ESPI_EV_TNF) {
315 fsl_espi_tx(fsl, dout);
316 /* Set up the next iteration */
317 if (len > 4) {
318 len -= 4;
319 dout += 4;
320 }
321 }
322
323 event = in_be32(&espi->event);
324 if (event & ESPI_EV_RNE) {
325 rf_cnt = ((event & ESPI_EV_RFCNT_MASK)
326 >> ESPI_EV_RFCNT_SHIFT);
327 if (rf_cnt >= 4)
328 rx_bytes = 4;
329 else if (num_blks == 1 && rf_cnt == num_bytes)
330 rx_bytes = num_bytes;
331 else
332 continue;
333 if (fsl_espi_rx(fsl, din, rx_bytes)
334 == rx_bytes) {
335 num_blks--;
336 if (din)
337 din = (unsigned char *)din
338 + rx_bytes;
339 }
340 }
341 }
342 if (data_in) {
343 memcpy(data_in, buffer + 2 * cmd_len, tran_len);
344 if (*buffer == 0x0b) {
345 data_in += tran_len;
346 data_len -= tran_len;
347 *(int *)buffer += tran_len;
348 }
349 }
350 spi_cs_deactivate(slave);
351 }
352
353 free(buffer);
354 return 0;
355 }
356
spi_cs_is_valid(unsigned int bus,unsigned int cs)357 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
358 {
359 return bus == 0 && cs < ESPI_MAX_CS_NUM;
360 }
361
spi_cs_activate(struct spi_slave * slave)362 void spi_cs_activate(struct spi_slave *slave)
363 {
364 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave);
365 ccsr_espi_t *espi = fsl->espi;
366 unsigned int com = 0;
367 size_t data_len = fsl->data_len;
368
369 com &= ~(ESPI_COM_CS(0x3) | ESPI_COM_TRANLEN(0xFFFF));
370 com |= ESPI_COM_CS(slave->cs);
371 com |= ESPI_COM_TRANLEN(data_len - 1);
372 out_be32(&espi->com, com);
373 }
374
spi_cs_deactivate(struct spi_slave * slave)375 void spi_cs_deactivate(struct spi_slave *slave)
376 {
377 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave);
378 ccsr_espi_t *espi = fsl->espi;
379
380 /* clear the RXCNT and TXCNT */
381 out_be32(&espi->mode, in_be32(&espi->mode) & (~ESPI_MODE_EN));
382 out_be32(&espi->mode, in_be32(&espi->mode) | ESPI_MODE_EN);
383 }
384