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 25 #include "spi-fsl-cpm.h" 26 #include "spi-fsl-lib.h" 27 #include "spi-fsl-spi.h" 28 29 /* CPM1 and CPM2 are mutually exclusive. */ 30 #ifdef CONFIG_CPM1 31 #include <asm/cpm1.h> 32 #define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0) 33 #else 34 #include <asm/cpm2.h> 35 #define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0) 36 #endif 37 38 #define SPIE_TXB 0x00000200 /* Last char is written to tx fifo */ 39 #define SPIE_RXB 0x00000100 /* Last char is written to rx buf */ 40 41 /* SPCOM register values */ 42 #define SPCOM_STR (1 << 23) /* Start transmit */ 43 44 #define SPI_PRAM_SIZE 0x100 45 #define SPI_MRBLR ((unsigned int)PAGE_SIZE) 46 47 static void *fsl_dummy_rx; 48 static DEFINE_MUTEX(fsl_dummy_rx_lock); 49 static int fsl_dummy_rx_refcnt; 50 51 void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi) 52 { 53 if (mspi->flags & SPI_QE) { 54 qe_issue_cmd(QE_INIT_TX_RX, mspi->subblock, 55 QE_CR_PROTOCOL_UNSPECIFIED, 0); 56 } else { 57 if (mspi->flags & SPI_CPM1) { 58 out_be32(&mspi->pram->rstate, 0); 59 out_be16(&mspi->pram->rbptr, 60 in_be16(&mspi->pram->rbase)); 61 out_be32(&mspi->pram->tstate, 0); 62 out_be16(&mspi->pram->tbptr, 63 in_be16(&mspi->pram->tbase)); 64 } else { 65 cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX); 66 } 67 } 68 } 69 EXPORT_SYMBOL_GPL(fsl_spi_cpm_reinit_txrx); 70 71 static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi) 72 { 73 struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd; 74 struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd; 75 unsigned int xfer_len = min(mspi->count, SPI_MRBLR); 76 unsigned int xfer_ofs; 77 struct fsl_spi_reg *reg_base = mspi->reg_base; 78 79 xfer_ofs = mspi->xfer_in_progress->len - mspi->count; 80 81 if (mspi->rx_dma == mspi->dma_dummy_rx) 82 out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma); 83 else 84 out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma + xfer_ofs); 85 out_be16(&rx_bd->cbd_datlen, 0); 86 out_be16(&rx_bd->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP); 87 88 if (mspi->tx_dma == mspi->dma_dummy_tx) 89 out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma); 90 else 91 out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma + xfer_ofs); 92 out_be16(&tx_bd->cbd_datlen, xfer_len); 93 out_be16(&tx_bd->cbd_sc, BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP | 94 BD_SC_LAST); 95 96 /* start transfer */ 97 mpc8xxx_spi_write_reg(®_base->command, SPCOM_STR); 98 } 99 100 int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi, 101 struct spi_transfer *t, bool is_dma_mapped) 102 { 103 struct device *dev = mspi->dev; 104 struct fsl_spi_reg *reg_base = mspi->reg_base; 105 106 if (is_dma_mapped) { 107 mspi->map_tx_dma = 0; 108 mspi->map_rx_dma = 0; 109 } else { 110 mspi->map_tx_dma = 1; 111 mspi->map_rx_dma = 1; 112 } 113 114 if (!t->tx_buf) { 115 mspi->tx_dma = mspi->dma_dummy_tx; 116 mspi->map_tx_dma = 0; 117 } 118 119 if (!t->rx_buf) { 120 mspi->rx_dma = mspi->dma_dummy_rx; 121 mspi->map_rx_dma = 0; 122 } 123 124 if (mspi->map_tx_dma) { 125 void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */ 126 127 mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len, 128 DMA_TO_DEVICE); 129 if (dma_mapping_error(dev, mspi->tx_dma)) { 130 dev_err(dev, "unable to map tx dma\n"); 131 return -ENOMEM; 132 } 133 } else if (t->tx_buf) { 134 mspi->tx_dma = t->tx_dma; 135 } 136 137 if (mspi->map_rx_dma) { 138 mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len, 139 DMA_FROM_DEVICE); 140 if (dma_mapping_error(dev, mspi->rx_dma)) { 141 dev_err(dev, "unable to map rx dma\n"); 142 goto err_rx_dma; 143 } 144 } else if (t->rx_buf) { 145 mspi->rx_dma = t->rx_dma; 146 } 147 148 /* enable rx ints */ 149 mpc8xxx_spi_write_reg(®_base->mask, SPIE_RXB); 150 151 mspi->xfer_in_progress = t; 152 mspi->count = t->len; 153 154 /* start CPM transfers */ 155 fsl_spi_cpm_bufs_start(mspi); 156 157 return 0; 158 159 err_rx_dma: 160 if (mspi->map_tx_dma) 161 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE); 162 return -ENOMEM; 163 } 164 EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs); 165 166 void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi) 167 { 168 struct device *dev = mspi->dev; 169 struct spi_transfer *t = mspi->xfer_in_progress; 170 171 if (mspi->map_tx_dma) 172 dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE); 173 if (mspi->map_rx_dma) 174 dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE); 175 mspi->xfer_in_progress = NULL; 176 } 177 EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs_complete); 178 179 void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events) 180 { 181 u16 len; 182 struct fsl_spi_reg *reg_base = mspi->reg_base; 183 184 dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__, 185 in_be16(&mspi->rx_bd->cbd_datlen), mspi->count); 186 187 len = in_be16(&mspi->rx_bd->cbd_datlen); 188 if (len > mspi->count) { 189 WARN_ON(1); 190 len = mspi->count; 191 } 192 193 /* Clear the events */ 194 mpc8xxx_spi_write_reg(®_base->event, events); 195 196 mspi->count -= len; 197 if (mspi->count) 198 fsl_spi_cpm_bufs_start(mspi); 199 else 200 complete(&mspi->done); 201 } 202 EXPORT_SYMBOL_GPL(fsl_spi_cpm_irq); 203 204 static void *fsl_spi_alloc_dummy_rx(void) 205 { 206 mutex_lock(&fsl_dummy_rx_lock); 207 208 if (!fsl_dummy_rx) 209 fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL); 210 if (fsl_dummy_rx) 211 fsl_dummy_rx_refcnt++; 212 213 mutex_unlock(&fsl_dummy_rx_lock); 214 215 return fsl_dummy_rx; 216 } 217 218 static void fsl_spi_free_dummy_rx(void) 219 { 220 mutex_lock(&fsl_dummy_rx_lock); 221 222 switch (fsl_dummy_rx_refcnt) { 223 case 0: 224 WARN_ON(1); 225 break; 226 case 1: 227 kfree(fsl_dummy_rx); 228 fsl_dummy_rx = NULL; 229 fallthrough; 230 default: 231 fsl_dummy_rx_refcnt--; 232 break; 233 } 234 235 mutex_unlock(&fsl_dummy_rx_lock); 236 } 237 238 static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi) 239 { 240 struct device *dev = mspi->dev; 241 struct device_node *np = dev->of_node; 242 const u32 *iprop; 243 int size; 244 void __iomem *spi_base; 245 unsigned long pram_ofs = -ENOMEM; 246 247 /* Can't use of_address_to_resource(), QE muram isn't at 0. */ 248 iprop = of_get_property(np, "reg", &size); 249 250 /* QE with a fixed pram location? */ 251 if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4) 252 return cpm_muram_alloc_fixed(iprop[2], SPI_PRAM_SIZE); 253 254 /* QE but with a dynamic pram location? */ 255 if (mspi->flags & SPI_QE) { 256 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64); 257 qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, mspi->subblock, 258 QE_CR_PROTOCOL_UNSPECIFIED, pram_ofs); 259 return pram_ofs; 260 } 261 262 spi_base = of_iomap(np, 1); 263 if (spi_base == NULL) 264 return -EINVAL; 265 266 if (mspi->flags & SPI_CPM2) { 267 pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64); 268 out_be16(spi_base, pram_ofs); 269 } 270 271 iounmap(spi_base); 272 return pram_ofs; 273 } 274 275 int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi) 276 { 277 struct device *dev = mspi->dev; 278 struct device_node *np = dev->of_node; 279 const u32 *iprop; 280 int size; 281 unsigned long bds_ofs; 282 283 if (!(mspi->flags & SPI_CPM_MODE)) 284 return 0; 285 286 if (!fsl_spi_alloc_dummy_rx()) 287 return -ENOMEM; 288 289 if (mspi->flags & SPI_QE) { 290 iprop = of_get_property(np, "cell-index", &size); 291 if (iprop && size == sizeof(*iprop)) 292 mspi->subblock = *iprop; 293 294 switch (mspi->subblock) { 295 default: 296 dev_warn(dev, "cell-index unspecified, assuming SPI1\n"); 297 fallthrough; 298 case 0: 299 mspi->subblock = QE_CR_SUBBLOCK_SPI1; 300 break; 301 case 1: 302 mspi->subblock = QE_CR_SUBBLOCK_SPI2; 303 break; 304 } 305 } 306 307 if (mspi->flags & SPI_CPM1) { 308 void *pram; 309 310 pram = devm_platform_ioremap_resource(to_platform_device(dev), 311 1); 312 if (IS_ERR(pram)) 313 mspi->pram = NULL; 314 else 315 mspi->pram = pram; 316 } else { 317 unsigned long pram_ofs = fsl_spi_cpm_get_pram(mspi); 318 319 if (IS_ERR_VALUE(pram_ofs)) 320 mspi->pram = NULL; 321 else 322 mspi->pram = cpm_muram_addr(pram_ofs); 323 } 324 if (mspi->pram == NULL) { 325 dev_err(dev, "can't allocate spi parameter ram\n"); 326 goto err_pram; 327 } 328 329 bds_ofs = cpm_muram_alloc(sizeof(*mspi->tx_bd) + 330 sizeof(*mspi->rx_bd), 8); 331 if (IS_ERR_VALUE(bds_ofs)) { 332 dev_err(dev, "can't allocate bds\n"); 333 goto err_bds; 334 } 335 336 mspi->dma_dummy_tx = dma_map_single(dev, empty_zero_page, PAGE_SIZE, 337 DMA_TO_DEVICE); 338 if (dma_mapping_error(dev, mspi->dma_dummy_tx)) { 339 dev_err(dev, "unable to map dummy tx buffer\n"); 340 goto err_dummy_tx; 341 } 342 343 mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR, 344 DMA_FROM_DEVICE); 345 if (dma_mapping_error(dev, mspi->dma_dummy_rx)) { 346 dev_err(dev, "unable to map dummy rx buffer\n"); 347 goto err_dummy_rx; 348 } 349 350 mspi->tx_bd = cpm_muram_addr(bds_ofs); 351 mspi->rx_bd = cpm_muram_addr(bds_ofs + sizeof(*mspi->tx_bd)); 352 353 /* Initialize parameter ram. */ 354 out_be16(&mspi->pram->tbase, cpm_muram_offset(mspi->tx_bd)); 355 out_be16(&mspi->pram->rbase, cpm_muram_offset(mspi->rx_bd)); 356 out_8(&mspi->pram->tfcr, CPMFCR_EB | CPMFCR_GBL); 357 out_8(&mspi->pram->rfcr, CPMFCR_EB | CPMFCR_GBL); 358 out_be16(&mspi->pram->mrblr, SPI_MRBLR); 359 out_be32(&mspi->pram->rstate, 0); 360 out_be32(&mspi->pram->rdp, 0); 361 out_be16(&mspi->pram->rbptr, 0); 362 out_be16(&mspi->pram->rbc, 0); 363 out_be32(&mspi->pram->rxtmp, 0); 364 out_be32(&mspi->pram->tstate, 0); 365 out_be32(&mspi->pram->tdp, 0); 366 out_be16(&mspi->pram->tbptr, 0); 367 out_be16(&mspi->pram->tbc, 0); 368 out_be32(&mspi->pram->txtmp, 0); 369 370 return 0; 371 372 err_dummy_rx: 373 dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE); 374 err_dummy_tx: 375 cpm_muram_free(bds_ofs); 376 err_bds: 377 if (!(mspi->flags & SPI_CPM1)) 378 cpm_muram_free(cpm_muram_offset(mspi->pram)); 379 err_pram: 380 fsl_spi_free_dummy_rx(); 381 return -ENOMEM; 382 } 383 EXPORT_SYMBOL_GPL(fsl_spi_cpm_init); 384 385 void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi) 386 { 387 struct device *dev = mspi->dev; 388 389 if (!(mspi->flags & SPI_CPM_MODE)) 390 return; 391 392 dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE); 393 dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE); 394 cpm_muram_free(cpm_muram_offset(mspi->tx_bd)); 395 if (!(mspi->flags & SPI_CPM1)) 396 cpm_muram_free(cpm_muram_offset(mspi->pram)); 397 fsl_spi_free_dummy_rx(); 398 } 399 EXPORT_SYMBOL_GPL(fsl_spi_cpm_free); 400 401 MODULE_LICENSE("GPL"); 402