1 /* 2 * eSPI controller driver. 3 * 4 * Copyright 2010-2011 Freescale Semiconductor, Inc. 5 * Author: Mingkai Hu (Mingkai.hu@freescale.com) 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #include <common.h> 11 12 #include <malloc.h> 13 #include <spi.h> 14 #include <asm/immap_85xx.h> 15 16 struct fsl_spi_slave { 17 struct spi_slave slave; 18 ccsr_espi_t *espi; 19 unsigned int div16; 20 unsigned int pm; 21 int tx_timeout; 22 unsigned int mode; 23 size_t cmd_len; 24 u8 cmd_buf[16]; 25 size_t data_len; 26 unsigned int max_transfer_length; 27 }; 28 29 #define to_fsl_spi_slave(s) container_of(s, struct fsl_spi_slave, slave) 30 #define US_PER_SECOND 1000000UL 31 32 #define ESPI_MAX_CS_NUM 4 33 #define ESPI_FIFO_WIDTH_BIT 32 34 35 #define ESPI_EV_RNE (1 << 9) 36 #define ESPI_EV_TNF (1 << 8) 37 #define ESPI_EV_DON (1 << 14) 38 #define ESPI_EV_TXE (1 << 15) 39 #define ESPI_EV_RFCNT_SHIFT 24 40 #define ESPI_EV_RFCNT_MASK (0x3f << ESPI_EV_RFCNT_SHIFT) 41 42 #define ESPI_MODE_EN (1 << 31) /* Enable interface */ 43 #define ESPI_MODE_TXTHR(x) ((x) << 8) /* Tx FIFO threshold */ 44 #define ESPI_MODE_RXTHR(x) ((x) << 0) /* Rx FIFO threshold */ 45 46 #define ESPI_COM_CS(x) ((x) << 30) 47 #define ESPI_COM_TRANLEN(x) ((x) << 0) 48 49 #define ESPI_CSMODE_CI_INACTIVEHIGH (1 << 31) 50 #define ESPI_CSMODE_CP_BEGIN_EDGCLK (1 << 30) 51 #define ESPI_CSMODE_REV_MSB_FIRST (1 << 29) 52 #define ESPI_CSMODE_DIV16 (1 << 28) 53 #define ESPI_CSMODE_PM(x) ((x) << 24) 54 #define ESPI_CSMODE_POL_ASSERTED_LOW (1 << 20) 55 #define ESPI_CSMODE_LEN(x) ((x) << 16) 56 #define ESPI_CSMODE_CSBEF(x) ((x) << 12) 57 #define ESPI_CSMODE_CSAFT(x) ((x) << 8) 58 #define ESPI_CSMODE_CSCG(x) ((x) << 3) 59 60 #define ESPI_CSMODE_INIT_VAL (ESPI_CSMODE_POL_ASSERTED_LOW | \ 61 ESPI_CSMODE_CSBEF(0) | ESPI_CSMODE_CSAFT(0) | \ 62 ESPI_CSMODE_CSCG(1)) 63 64 #define ESPI_MAX_DATA_TRANSFER_LEN 0xFFF0 65 66 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 67 unsigned int max_hz, unsigned int mode) 68 { 69 struct fsl_spi_slave *fsl; 70 sys_info_t sysinfo; 71 unsigned long spibrg = 0; 72 unsigned long spi_freq = 0; 73 unsigned char pm = 0; 74 75 if (!spi_cs_is_valid(bus, cs)) 76 return NULL; 77 78 fsl = spi_alloc_slave(struct fsl_spi_slave, bus, cs); 79 if (!fsl) 80 return NULL; 81 82 fsl->espi = (void *)(CONFIG_SYS_MPC85xx_ESPI_ADDR); 83 fsl->mode = mode; 84 fsl->max_transfer_length = ESPI_MAX_DATA_TRANSFER_LEN; 85 86 /* Set eSPI BRG clock source */ 87 get_sys_info(&sysinfo); 88 spibrg = sysinfo.freq_systembus / 2; 89 fsl->div16 = 0; 90 if ((spibrg / max_hz) > 32) { 91 fsl->div16 = ESPI_CSMODE_DIV16; 92 pm = spibrg / (max_hz * 16 * 2); 93 if (pm > 16) { 94 pm = 16; 95 debug("Requested speed is too low: %d Hz, %ld Hz " 96 "is used.\n", max_hz, spibrg / (32 * 16)); 97 } 98 } else 99 pm = spibrg / (max_hz * 2); 100 if (pm) 101 pm--; 102 fsl->pm = pm; 103 104 if (fsl->div16) 105 spi_freq = spibrg / ((pm + 1) * 2 * 16); 106 else 107 spi_freq = spibrg / ((pm + 1) * 2); 108 109 /* set tx_timeout to 10 times of one espi FIFO entry go out */ 110 fsl->tx_timeout = DIV_ROUND_UP((US_PER_SECOND * ESPI_FIFO_WIDTH_BIT 111 * 10), spi_freq); 112 113 return &fsl->slave; 114 } 115 116 void spi_free_slave(struct spi_slave *slave) 117 { 118 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave); 119 free(fsl); 120 } 121 122 void spi_init(void) 123 { 124 125 } 126 127 int spi_claim_bus(struct spi_slave *slave) 128 { 129 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave); 130 ccsr_espi_t *espi = fsl->espi; 131 unsigned char pm = fsl->pm; 132 unsigned int cs = slave->cs; 133 unsigned int mode = fsl->mode; 134 unsigned int div16 = fsl->div16; 135 int i; 136 137 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, cs); 138 139 /* Enable eSPI interface */ 140 out_be32(&espi->mode, ESPI_MODE_RXTHR(3) 141 | ESPI_MODE_TXTHR(4) | ESPI_MODE_EN); 142 143 out_be32(&espi->event, 0xffffffff); /* Clear all eSPI events */ 144 out_be32(&espi->mask, 0x00000000); /* Mask all eSPI interrupts */ 145 146 /* Init CS mode interface */ 147 for (i = 0; i < ESPI_MAX_CS_NUM; i++) 148 out_be32(&espi->csmode[i], ESPI_CSMODE_INIT_VAL); 149 150 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) & 151 ~(ESPI_CSMODE_PM(0xF) | ESPI_CSMODE_DIV16 152 | ESPI_CSMODE_CI_INACTIVEHIGH | ESPI_CSMODE_CP_BEGIN_EDGCLK 153 | ESPI_CSMODE_REV_MSB_FIRST | ESPI_CSMODE_LEN(0xF))); 154 155 /* Set eSPI BRG clock source */ 156 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) 157 | ESPI_CSMODE_PM(pm) | div16); 158 159 /* Set eSPI mode */ 160 if (mode & SPI_CPHA) 161 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) 162 | ESPI_CSMODE_CP_BEGIN_EDGCLK); 163 if (mode & SPI_CPOL) 164 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) 165 | ESPI_CSMODE_CI_INACTIVEHIGH); 166 167 /* Character bit order: msb first */ 168 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) 169 | ESPI_CSMODE_REV_MSB_FIRST); 170 171 /* Character length in bits, between 0x3~0xf, i.e. 4bits~16bits */ 172 out_be32(&espi->csmode[cs], in_be32(&espi->csmode[cs]) 173 | ESPI_CSMODE_LEN(7)); 174 175 return 0; 176 } 177 178 void spi_release_bus(struct spi_slave *slave) 179 { 180 181 } 182 183 static void fsl_espi_tx(struct fsl_spi_slave *fsl, const void *dout) 184 { 185 ccsr_espi_t *espi = fsl->espi; 186 unsigned int tmpdout, event; 187 int tmp_tx_timeout; 188 189 if (dout) 190 tmpdout = *(u32 *)dout; 191 else 192 tmpdout = 0; 193 194 out_be32(&espi->tx, tmpdout); 195 out_be32(&espi->event, ESPI_EV_TNF); 196 debug("***spi_xfer:...%08x written\n", tmpdout); 197 198 tmp_tx_timeout = fsl->tx_timeout; 199 /* Wait for eSPI transmit to go out */ 200 while (tmp_tx_timeout--) { 201 event = in_be32(&espi->event); 202 if (event & ESPI_EV_DON || event & ESPI_EV_TXE) { 203 out_be32(&espi->event, ESPI_EV_TXE); 204 break; 205 } 206 udelay(1); 207 } 208 209 if (tmp_tx_timeout < 0) 210 debug("***spi_xfer:...Tx timeout! event = %08x\n", event); 211 } 212 213 static int fsl_espi_rx(struct fsl_spi_slave *fsl, void *din, unsigned int bytes) 214 { 215 ccsr_espi_t *espi = fsl->espi; 216 unsigned int tmpdin, rx_times; 217 unsigned char *buf, *p_cursor; 218 219 if (bytes <= 0) 220 return 0; 221 222 rx_times = DIV_ROUND_UP(bytes, 4); 223 buf = (unsigned char *)malloc(4 * rx_times); 224 if (!buf) { 225 debug("SF: Failed to malloc memory.\n"); 226 return -1; 227 } 228 p_cursor = buf; 229 while (rx_times--) { 230 tmpdin = in_be32(&espi->rx); 231 debug("***spi_xfer:...%08x readed\n", tmpdin); 232 *(u32 *)p_cursor = tmpdin; 233 p_cursor += 4; 234 } 235 236 if (din) 237 memcpy(din, buf, bytes); 238 239 free(buf); 240 out_be32(&espi->event, ESPI_EV_RNE); 241 242 return bytes; 243 } 244 245 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *data_out, 246 void *data_in, unsigned long flags) 247 { 248 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave); 249 ccsr_espi_t *espi = fsl->espi; 250 unsigned int event, rx_bytes; 251 const void *dout = NULL; 252 void *din = NULL; 253 int len = 0; 254 int num_blks, num_chunks, max_tran_len, tran_len; 255 int num_bytes; 256 unsigned char *buffer = NULL; 257 size_t buf_len; 258 u8 *cmd_buf = fsl->cmd_buf; 259 size_t cmd_len = fsl->cmd_len; 260 size_t data_len = bitlen / 8; 261 size_t rx_offset = 0; 262 int rf_cnt; 263 264 max_tran_len = fsl->max_transfer_length; 265 switch (flags) { 266 case SPI_XFER_BEGIN: 267 cmd_len = fsl->cmd_len = data_len; 268 memcpy(cmd_buf, data_out, cmd_len); 269 return 0; 270 case 0: 271 case SPI_XFER_END: 272 if (bitlen == 0) { 273 spi_cs_deactivate(slave); 274 return 0; 275 } 276 buf_len = 2 * cmd_len + min(data_len, max_tran_len); 277 len = cmd_len + data_len; 278 rx_offset = cmd_len; 279 buffer = (unsigned char *)malloc(buf_len); 280 if (!buffer) { 281 debug("SF: Failed to malloc memory.\n"); 282 return 1; 283 } 284 memcpy(buffer, cmd_buf, cmd_len); 285 if (data_in == NULL) 286 memcpy(buffer + cmd_len, data_out, data_len); 287 break; 288 case SPI_XFER_BEGIN | SPI_XFER_END: 289 len = data_len; 290 buffer = (unsigned char *)malloc(len * 2); 291 if (!buffer) { 292 debug("SF: Failed to malloc memory.\n"); 293 return 1; 294 } 295 memcpy(buffer, data_out, len); 296 rx_offset = len; 297 cmd_len = 0; 298 break; 299 } 300 301 debug("spi_xfer: data_out %08X(%p) data_in %08X(%p) len %u\n", 302 *(uint *)data_out, data_out, *(uint *)data_in, data_in, len); 303 304 num_chunks = DIV_ROUND_UP(data_len, max_tran_len); 305 while (num_chunks--) { 306 if (data_in) 307 din = buffer + rx_offset; 308 dout = buffer; 309 tran_len = min(data_len , max_tran_len); 310 num_blks = DIV_ROUND_UP(tran_len + cmd_len, 4); 311 num_bytes = (tran_len + cmd_len) % 4; 312 fsl->data_len = tran_len + cmd_len; 313 spi_cs_activate(slave); 314 315 /* Clear all eSPI events */ 316 out_be32(&espi->event , 0xffffffff); 317 /* handle data in 32-bit chunks */ 318 while (num_blks) { 319 event = in_be32(&espi->event); 320 if (event & ESPI_EV_TNF) { 321 fsl_espi_tx(fsl, dout); 322 /* Set up the next iteration */ 323 if (len > 4) { 324 len -= 4; 325 dout += 4; 326 } 327 } 328 329 event = in_be32(&espi->event); 330 if (event & ESPI_EV_RNE) { 331 rf_cnt = ((event & ESPI_EV_RFCNT_MASK) 332 >> ESPI_EV_RFCNT_SHIFT); 333 if (rf_cnt >= 4) 334 rx_bytes = 4; 335 else if (num_blks == 1 && rf_cnt == num_bytes) 336 rx_bytes = num_bytes; 337 else 338 continue; 339 if (fsl_espi_rx(fsl, din, rx_bytes) 340 == rx_bytes) { 341 num_blks--; 342 if (din) 343 din = (unsigned char *)din 344 + rx_bytes; 345 } 346 } 347 } 348 if (data_in) { 349 memcpy(data_in, buffer + 2 * cmd_len, tran_len); 350 if (*buffer == 0x0b) { 351 data_in += tran_len; 352 data_len -= tran_len; 353 *(int *)buffer += tran_len; 354 } 355 } 356 spi_cs_deactivate(slave); 357 } 358 359 free(buffer); 360 return 0; 361 } 362 363 int spi_cs_is_valid(unsigned int bus, unsigned int cs) 364 { 365 return bus == 0 && cs < ESPI_MAX_CS_NUM; 366 } 367 368 void spi_cs_activate(struct spi_slave *slave) 369 { 370 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave); 371 ccsr_espi_t *espi = fsl->espi; 372 unsigned int com = 0; 373 size_t data_len = fsl->data_len; 374 375 com &= ~(ESPI_COM_CS(0x3) | ESPI_COM_TRANLEN(0xFFFF)); 376 com |= ESPI_COM_CS(slave->cs); 377 com |= ESPI_COM_TRANLEN(data_len - 1); 378 out_be32(&espi->com, com); 379 } 380 381 void spi_cs_deactivate(struct spi_slave *slave) 382 { 383 struct fsl_spi_slave *fsl = to_fsl_spi_slave(slave); 384 ccsr_espi_t *espi = fsl->espi; 385 386 /* clear the RXCNT and TXCNT */ 387 out_be32(&espi->mode, in_be32(&espi->mode) & (~ESPI_MODE_EN)); 388 out_be32(&espi->mode, in_be32(&espi->mode) | ESPI_MODE_EN); 389 } 390