1 // SPDX-License-Identifier: GPL-2.0 2 // PCI1xxxx SPI driver 3 // Copyright (C) 2022 Microchip Technology Inc. 4 // Authors: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com> 5 // Kumaravel Thiagarajan <Kumaravel.Thiagarajan@microchip.com> 6 7 8 #include <linux/module.h> 9 #include <linux/pci.h> 10 #include <linux/spi/spi.h> 11 #include <linux/delay.h> 12 13 #define DRV_NAME "spi-pci1xxxx" 14 15 #define SYS_FREQ_DEFAULT (62500000) 16 17 #define PCI1XXXX_SPI_MAX_CLOCK_HZ (30000000) 18 #define PCI1XXXX_SPI_CLK_20MHZ (20000000) 19 #define PCI1XXXX_SPI_CLK_15MHZ (15000000) 20 #define PCI1XXXX_SPI_CLK_12MHZ (12000000) 21 #define PCI1XXXX_SPI_CLK_10MHZ (10000000) 22 #define PCI1XXXX_SPI_MIN_CLOCK_HZ (2000000) 23 24 #define PCI1XXXX_SPI_BUFFER_SIZE (320) 25 26 #define SPI_MST_CTL_DEVSEL_MASK (GENMASK(27, 25)) 27 #define SPI_MST_CTL_CMD_LEN_MASK (GENMASK(16, 8)) 28 #define SPI_MST_CTL_SPEED_MASK (GENMASK(7, 5)) 29 #define SPI_MSI_VECTOR_SEL_MASK (GENMASK(4, 4)) 30 31 #define SPI_MST_CTL_FORCE_CE (BIT(4)) 32 #define SPI_MST_CTL_MODE_SEL (BIT(2)) 33 #define SPI_MST_CTL_GO (BIT(0)) 34 35 #define SPI_MST1_ADDR_BASE (0x800) 36 37 /* x refers to SPI Host Controller HW instance id in the below macros - 0 or 1 */ 38 39 #define SPI_MST_CMD_BUF_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x00) 40 #define SPI_MST_RSP_BUF_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x200) 41 #define SPI_MST_CTL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x400) 42 #define SPI_MST_EVENT_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x420) 43 #define SPI_MST_EVENT_MASK_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x424) 44 #define SPI_MST_PAD_CTL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x460) 45 #define SPIALERT_MST_DB_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x464) 46 #define SPIALERT_MST_VAL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x468) 47 #define SPI_PCI_CTRL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x480) 48 49 #define PCI1XXXX_IRQ_FLAGS (IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE) 50 #define SPI_MAX_DATA_LEN 320 51 52 #define PCI1XXXX_SPI_TIMEOUT (msecs_to_jiffies(100)) 53 54 #define SPI_INTR BIT(8) 55 #define SPI_FORCE_CE BIT(4) 56 57 #define SPI_CHIP_SEL_COUNT 7 58 #define VENDOR_ID_MCHP 0x1055 59 60 #define SPI_SUSPEND_CONFIG 0x101 61 #define SPI_RESUME_CONFIG 0x203 62 63 struct pci1xxxx_spi_internal { 64 u8 hw_inst; 65 bool spi_xfer_in_progress; 66 int irq; 67 struct completion spi_xfer_done; 68 struct spi_master *spi_host; 69 struct pci1xxxx_spi *parent; 70 struct { 71 unsigned int dev_sel : 3; 72 unsigned int msi_vector_sel : 1; 73 } prev_val; 74 }; 75 76 struct pci1xxxx_spi { 77 struct pci_dev *dev; 78 u8 total_hw_instances; 79 void __iomem *reg_base; 80 struct pci1xxxx_spi_internal *spi_int[]; 81 }; 82 83 static const struct pci_device_id pci1xxxx_spi_pci_id_table[] = { 84 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0001), 0, 0, 0x02}, 85 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0002), 0, 0, 0x01}, 86 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0003), 0, 0, 0x11}, 87 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01}, 88 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0001), 0, 0, 0x02}, 89 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0002), 0, 0, 0x01}, 90 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0003), 0, 0, 0x11}, 91 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01}, 92 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0001), 0, 0, 0x02}, 93 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0002), 0, 0, 0x01}, 94 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0003), 0, 0, 0x11}, 95 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01}, 96 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0001), 0, 0, 0x02}, 97 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0002), 0, 0, 0x01}, 98 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0003), 0, 0, 0x11}, 99 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01}, 100 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0001), 0, 0, 0x02}, 101 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0002), 0, 0, 0x01}, 102 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0003), 0, 0, 0x11}, 103 { PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01}, 104 { 0, } 105 }; 106 107 MODULE_DEVICE_TABLE(pci, pci1xxxx_spi_pci_id_table); 108 109 static void pci1xxxx_spi_set_cs(struct spi_device *spi, bool enable) 110 { 111 struct pci1xxxx_spi_internal *p = spi_controller_get_devdata(spi->controller); 112 struct pci1xxxx_spi *par = p->parent; 113 u32 regval; 114 115 /* Set the DEV_SEL bits of the SPI_MST_CTL_REG */ 116 regval = readl(par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 117 if (!enable) { 118 regval |= SPI_FORCE_CE; 119 regval &= ~SPI_MST_CTL_DEVSEL_MASK; 120 regval |= (spi_get_chipselect(spi, 0) << 25); 121 } else { 122 regval &= ~SPI_FORCE_CE; 123 } 124 writel(regval, par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 125 } 126 127 static u8 pci1xxxx_get_clock_div(u32 hz) 128 { 129 u8 val = 0; 130 131 if (hz >= PCI1XXXX_SPI_MAX_CLOCK_HZ) 132 val = 2; 133 else if ((hz < PCI1XXXX_SPI_MAX_CLOCK_HZ) && (hz >= PCI1XXXX_SPI_CLK_20MHZ)) 134 val = 3; 135 else if ((hz < PCI1XXXX_SPI_CLK_20MHZ) && (hz >= PCI1XXXX_SPI_CLK_15MHZ)) 136 val = 4; 137 else if ((hz < PCI1XXXX_SPI_CLK_15MHZ) && (hz >= PCI1XXXX_SPI_CLK_12MHZ)) 138 val = 5; 139 else if ((hz < PCI1XXXX_SPI_CLK_12MHZ) && (hz >= PCI1XXXX_SPI_CLK_10MHZ)) 140 val = 6; 141 else if ((hz < PCI1XXXX_SPI_CLK_10MHZ) && (hz >= PCI1XXXX_SPI_MIN_CLOCK_HZ)) 142 val = 7; 143 else 144 val = 2; 145 146 return val; 147 } 148 149 static int pci1xxxx_spi_transfer_one(struct spi_controller *spi_ctlr, 150 struct spi_device *spi, struct spi_transfer *xfer) 151 { 152 struct pci1xxxx_spi_internal *p = spi_controller_get_devdata(spi_ctlr); 153 int mode, len, loop_iter, transfer_len; 154 struct pci1xxxx_spi *par = p->parent; 155 unsigned long bytes_transfered; 156 unsigned long bytes_recvd; 157 unsigned long loop_count; 158 u8 *rx_buf, result; 159 const u8 *tx_buf; 160 u32 regval; 161 u8 clkdiv; 162 163 p->spi_xfer_in_progress = true; 164 mode = spi->mode; 165 clkdiv = pci1xxxx_get_clock_div(xfer->speed_hz); 166 tx_buf = xfer->tx_buf; 167 rx_buf = xfer->rx_buf; 168 transfer_len = xfer->len; 169 regval = readl(par->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst)); 170 writel(regval, par->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst)); 171 172 if (tx_buf) { 173 bytes_transfered = 0; 174 bytes_recvd = 0; 175 loop_count = transfer_len / SPI_MAX_DATA_LEN; 176 if (transfer_len % SPI_MAX_DATA_LEN != 0) 177 loop_count += 1; 178 179 for (loop_iter = 0; loop_iter < loop_count; loop_iter++) { 180 len = SPI_MAX_DATA_LEN; 181 if ((transfer_len % SPI_MAX_DATA_LEN != 0) && 182 (loop_iter == loop_count - 1)) 183 len = transfer_len % SPI_MAX_DATA_LEN; 184 185 reinit_completion(&p->spi_xfer_done); 186 memcpy_toio(par->reg_base + SPI_MST_CMD_BUF_OFFSET(p->hw_inst), 187 &tx_buf[bytes_transfered], len); 188 bytes_transfered += len; 189 regval = readl(par->reg_base + 190 SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 191 regval &= ~(SPI_MST_CTL_MODE_SEL | SPI_MST_CTL_CMD_LEN_MASK | 192 SPI_MST_CTL_SPEED_MASK); 193 194 if (mode == SPI_MODE_3) 195 regval |= SPI_MST_CTL_MODE_SEL; 196 else 197 regval &= ~SPI_MST_CTL_MODE_SEL; 198 199 regval |= (clkdiv << 5); 200 regval &= ~SPI_MST_CTL_CMD_LEN_MASK; 201 regval |= (len << 8); 202 writel(regval, par->reg_base + 203 SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 204 regval = readl(par->reg_base + 205 SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 206 regval |= SPI_MST_CTL_GO; 207 writel(regval, par->reg_base + 208 SPI_MST_CTL_REG_OFFSET(p->hw_inst)); 209 210 /* Wait for DMA_TERM interrupt */ 211 result = wait_for_completion_timeout(&p->spi_xfer_done, 212 PCI1XXXX_SPI_TIMEOUT); 213 if (!result) 214 return -ETIMEDOUT; 215 216 if (rx_buf) { 217 memcpy_fromio(&rx_buf[bytes_recvd], par->reg_base + 218 SPI_MST_RSP_BUF_OFFSET(p->hw_inst), len); 219 bytes_recvd += len; 220 } 221 } 222 } 223 p->spi_xfer_in_progress = false; 224 225 return 0; 226 } 227 228 static irqreturn_t pci1xxxx_spi_isr(int irq, void *dev) 229 { 230 struct pci1xxxx_spi_internal *p = dev; 231 irqreturn_t spi_int_fired = IRQ_NONE; 232 u32 regval; 233 234 /* Clear the SPI GO_BIT Interrupt */ 235 regval = readl(p->parent->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst)); 236 if (regval & SPI_INTR) { 237 /* Clear xfer_done */ 238 complete(&p->spi_xfer_done); 239 spi_int_fired = IRQ_HANDLED; 240 } 241 242 writel(regval, p->parent->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst)); 243 244 return spi_int_fired; 245 } 246 247 static int pci1xxxx_spi_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 248 { 249 u8 hw_inst_cnt, iter, start, only_sec_inst; 250 struct pci1xxxx_spi_internal *spi_sub_ptr; 251 struct device *dev = &pdev->dev; 252 struct pci1xxxx_spi *spi_bus; 253 struct spi_master *spi_host; 254 u32 regval; 255 int ret; 256 257 hw_inst_cnt = ent->driver_data & 0x0f; 258 start = (ent->driver_data & 0xf0) >> 4; 259 if (start == 1) 260 only_sec_inst = 1; 261 else 262 only_sec_inst = 0; 263 264 spi_bus = devm_kzalloc(&pdev->dev, 265 struct_size(spi_bus, spi_int, hw_inst_cnt), 266 GFP_KERNEL); 267 if (!spi_bus) 268 return -ENOMEM; 269 270 spi_bus->dev = pdev; 271 spi_bus->total_hw_instances = hw_inst_cnt; 272 pci_set_master(pdev); 273 274 for (iter = 0; iter < hw_inst_cnt; iter++) { 275 spi_bus->spi_int[iter] = devm_kzalloc(&pdev->dev, 276 sizeof(struct pci1xxxx_spi_internal), 277 GFP_KERNEL); 278 spi_sub_ptr = spi_bus->spi_int[iter]; 279 spi_sub_ptr->spi_host = devm_spi_alloc_master(dev, sizeof(struct spi_master)); 280 if (!spi_sub_ptr->spi_host) 281 return -ENOMEM; 282 283 spi_sub_ptr->parent = spi_bus; 284 spi_sub_ptr->spi_xfer_in_progress = false; 285 286 if (!iter) { 287 ret = pcim_enable_device(pdev); 288 if (ret) 289 return -ENOMEM; 290 291 ret = pci_request_regions(pdev, DRV_NAME); 292 if (ret) 293 return -ENOMEM; 294 295 spi_bus->reg_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); 296 if (!spi_bus->reg_base) { 297 ret = -EINVAL; 298 goto error; 299 } 300 301 ret = pci_alloc_irq_vectors(pdev, hw_inst_cnt, hw_inst_cnt, 302 PCI_IRQ_ALL_TYPES); 303 if (ret < 0) { 304 dev_err(&pdev->dev, "Error allocating MSI vectors\n"); 305 goto error; 306 } 307 308 init_completion(&spi_sub_ptr->spi_xfer_done); 309 /* Initialize Interrupts - SPI_INT */ 310 regval = readl(spi_bus->reg_base + 311 SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst)); 312 regval &= ~SPI_INTR; 313 writel(regval, spi_bus->reg_base + 314 SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst)); 315 spi_sub_ptr->irq = pci_irq_vector(pdev, 0); 316 317 ret = devm_request_irq(&pdev->dev, spi_sub_ptr->irq, 318 pci1xxxx_spi_isr, PCI1XXXX_IRQ_FLAGS, 319 pci_name(pdev), spi_sub_ptr); 320 if (ret < 0) { 321 dev_err(&pdev->dev, "Unable to request irq : %d", 322 spi_sub_ptr->irq); 323 ret = -ENODEV; 324 goto error; 325 } 326 327 /* This register is only applicable for 1st instance */ 328 regval = readl(spi_bus->reg_base + SPI_PCI_CTRL_REG_OFFSET(0)); 329 if (!only_sec_inst) 330 regval |= (BIT(4)); 331 else 332 regval &= ~(BIT(4)); 333 334 writel(regval, spi_bus->reg_base + SPI_PCI_CTRL_REG_OFFSET(0)); 335 } 336 337 spi_sub_ptr->hw_inst = start++; 338 339 if (iter == 1) { 340 init_completion(&spi_sub_ptr->spi_xfer_done); 341 /* Initialize Interrupts - SPI_INT */ 342 regval = readl(spi_bus->reg_base + 343 SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst)); 344 regval &= ~SPI_INTR; 345 writel(regval, spi_bus->reg_base + 346 SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst)); 347 spi_sub_ptr->irq = pci_irq_vector(pdev, iter); 348 ret = devm_request_irq(&pdev->dev, spi_sub_ptr->irq, 349 pci1xxxx_spi_isr, PCI1XXXX_IRQ_FLAGS, 350 pci_name(pdev), spi_sub_ptr); 351 if (ret < 0) { 352 dev_err(&pdev->dev, "Unable to request irq : %d", 353 spi_sub_ptr->irq); 354 ret = -ENODEV; 355 goto error; 356 } 357 } 358 359 spi_host = spi_sub_ptr->spi_host; 360 spi_host->num_chipselect = SPI_CHIP_SEL_COUNT; 361 spi_host->mode_bits = SPI_MODE_0 | SPI_MODE_3 | SPI_RX_DUAL | 362 SPI_TX_DUAL | SPI_LOOP; 363 spi_host->transfer_one = pci1xxxx_spi_transfer_one; 364 spi_host->set_cs = pci1xxxx_spi_set_cs; 365 spi_host->bits_per_word_mask = SPI_BPW_MASK(8); 366 spi_host->max_speed_hz = PCI1XXXX_SPI_MAX_CLOCK_HZ; 367 spi_host->min_speed_hz = PCI1XXXX_SPI_MIN_CLOCK_HZ; 368 spi_host->flags = SPI_MASTER_MUST_TX; 369 spi_master_set_devdata(spi_host, spi_sub_ptr); 370 ret = devm_spi_register_master(dev, spi_host); 371 if (ret) 372 goto error; 373 } 374 pci_set_drvdata(pdev, spi_bus); 375 376 return 0; 377 378 error: 379 pci_release_regions(pdev); 380 return ret; 381 } 382 383 static void store_restore_config(struct pci1xxxx_spi *spi_ptr, 384 struct pci1xxxx_spi_internal *spi_sub_ptr, 385 u8 inst, bool store) 386 { 387 u32 regval; 388 389 if (store) { 390 regval = readl(spi_ptr->reg_base + 391 SPI_MST_CTL_REG_OFFSET(spi_sub_ptr->hw_inst)); 392 regval &= SPI_MST_CTL_DEVSEL_MASK; 393 spi_sub_ptr->prev_val.dev_sel = (regval >> 25) & 7; 394 regval = readl(spi_ptr->reg_base + 395 SPI_PCI_CTRL_REG_OFFSET(spi_sub_ptr->hw_inst)); 396 regval &= SPI_MSI_VECTOR_SEL_MASK; 397 spi_sub_ptr->prev_val.msi_vector_sel = (regval >> 4) & 1; 398 } else { 399 regval = readl(spi_ptr->reg_base + SPI_MST_CTL_REG_OFFSET(inst)); 400 regval &= ~SPI_MST_CTL_DEVSEL_MASK; 401 regval |= (spi_sub_ptr->prev_val.dev_sel << 25); 402 writel(regval, 403 spi_ptr->reg_base + SPI_MST_CTL_REG_OFFSET(inst)); 404 writel((spi_sub_ptr->prev_val.msi_vector_sel << 4), 405 spi_ptr->reg_base + SPI_PCI_CTRL_REG_OFFSET(inst)); 406 } 407 } 408 409 static int pci1xxxx_spi_resume(struct device *dev) 410 { 411 struct pci1xxxx_spi *spi_ptr = dev_get_drvdata(dev); 412 struct pci1xxxx_spi_internal *spi_sub_ptr; 413 u32 regval = SPI_RESUME_CONFIG; 414 u8 iter; 415 416 for (iter = 0; iter < spi_ptr->total_hw_instances; iter++) { 417 spi_sub_ptr = spi_ptr->spi_int[iter]; 418 spi_master_resume(spi_sub_ptr->spi_host); 419 writel(regval, spi_ptr->reg_base + 420 SPI_MST_EVENT_MASK_REG_OFFSET(iter)); 421 422 /* Restore config at resume */ 423 store_restore_config(spi_ptr, spi_sub_ptr, iter, 0); 424 } 425 426 return 0; 427 } 428 429 static int pci1xxxx_spi_suspend(struct device *dev) 430 { 431 struct pci1xxxx_spi *spi_ptr = dev_get_drvdata(dev); 432 struct pci1xxxx_spi_internal *spi_sub_ptr; 433 u32 reg1 = SPI_SUSPEND_CONFIG; 434 u8 iter; 435 436 for (iter = 0; iter < spi_ptr->total_hw_instances; iter++) { 437 spi_sub_ptr = spi_ptr->spi_int[iter]; 438 439 while (spi_sub_ptr->spi_xfer_in_progress) 440 msleep(20); 441 442 /* Store existing config before suspend */ 443 store_restore_config(spi_ptr, spi_sub_ptr, iter, 1); 444 spi_master_suspend(spi_sub_ptr->spi_host); 445 writel(reg1, spi_ptr->reg_base + 446 SPI_MST_EVENT_MASK_REG_OFFSET(iter)); 447 } 448 449 return 0; 450 } 451 452 static DEFINE_SIMPLE_DEV_PM_OPS(spi_pm_ops, pci1xxxx_spi_suspend, 453 pci1xxxx_spi_resume); 454 455 static struct pci_driver pci1xxxx_spi_driver = { 456 .name = DRV_NAME, 457 .id_table = pci1xxxx_spi_pci_id_table, 458 .probe = pci1xxxx_spi_probe, 459 .driver = { 460 .pm = pm_sleep_ptr(&spi_pm_ops), 461 }, 462 }; 463 464 module_pci_driver(pci1xxxx_spi_driver); 465 466 MODULE_DESCRIPTION("Microchip Technology Inc. pci1xxxx SPI bus driver"); 467 MODULE_AUTHOR("Tharun Kumar P<tharunkumar.pasumarthi@microchip.com>"); 468 MODULE_AUTHOR("Kumaravel Thiagarajan<kumaravel.thiagarajan@microchip.com>"); 469 MODULE_LICENSE("GPL v2"); 470