1 /* 2 * This file is provided under a dual BSD/GPLv2 license. When using or 3 * redistributing this file, you may do so under either license. 4 * 5 * Copyright(c) 2012 Intel Corporation. All rights reserved. 6 * 7 * GPL LICENSE SUMMARY 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of version 2 of the GNU General Public License as 11 * published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * The full GNU General Public License is included in this distribution 18 * in the file called LICENSE.GPL. 19 * 20 * BSD LICENSE 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 26 * * Redistributions of source code must retain the above copyright 27 * notice, this list of conditions and the following disclaimer. 28 * * Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in 30 * the documentation and/or other materials provided with the 31 * distribution. 32 * * Neither the name of Intel Corporation nor the names of its 33 * contributors may be used to endorse or promote products derived 34 * from this software without specific prior written permission. 35 * 36 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 37 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 38 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 39 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 40 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 42 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 43 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 44 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 45 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 46 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 47 */ 48 49 /* 50 * Supports the SMBus Message Transport (SMT) in the Intel Atom Processor 51 * S12xx Product Family. 52 * 53 * Features supported by this driver: 54 * Hardware PEC yes 55 * Block buffer yes 56 * Block process call transaction yes 57 * Slave mode no 58 */ 59 60 #include <linux/module.h> 61 #include <linux/pci.h> 62 #include <linux/kernel.h> 63 #include <linux/stddef.h> 64 #include <linux/completion.h> 65 #include <linux/dma-mapping.h> 66 #include <linux/i2c.h> 67 #include <linux/acpi.h> 68 #include <linux/interrupt.h> 69 70 #include <linux/io-64-nonatomic-lo-hi.h> 71 72 /* PCI Address Constants */ 73 #define SMBBAR 0 74 75 /* PCI DIDs for the Intel SMBus Message Transport (SMT) Devices */ 76 #define PCI_DEVICE_ID_INTEL_S1200_SMT0 0x0c59 77 #define PCI_DEVICE_ID_INTEL_S1200_SMT1 0x0c5a 78 #define PCI_DEVICE_ID_INTEL_CDF_SMT 0x18ac 79 #define PCI_DEVICE_ID_INTEL_DNV_SMT 0x19ac 80 #define PCI_DEVICE_ID_INTEL_EBG_SMT 0x1bff 81 #define PCI_DEVICE_ID_INTEL_AVOTON_SMT 0x1f15 82 83 #define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */ 84 #define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */ 85 86 /* Hardware Descriptor Constants - Control Field */ 87 #define ISMT_DESC_CWRL 0x01 /* Command/Write Length */ 88 #define ISMT_DESC_BLK 0X04 /* Perform Block Transaction */ 89 #define ISMT_DESC_FAIR 0x08 /* Set fairness flag upon successful arbit. */ 90 #define ISMT_DESC_PEC 0x10 /* Packet Error Code */ 91 #define ISMT_DESC_I2C 0x20 /* I2C Enable */ 92 #define ISMT_DESC_INT 0x40 /* Interrupt */ 93 #define ISMT_DESC_SOE 0x80 /* Stop On Error */ 94 95 /* Hardware Descriptor Constants - Status Field */ 96 #define ISMT_DESC_SCS 0x01 /* Success */ 97 #define ISMT_DESC_DLTO 0x04 /* Data Low Time Out */ 98 #define ISMT_DESC_NAK 0x08 /* NAK Received */ 99 #define ISMT_DESC_CRC 0x10 /* CRC Error */ 100 #define ISMT_DESC_CLTO 0x20 /* Clock Low Time Out */ 101 #define ISMT_DESC_COL 0x40 /* Collisions */ 102 #define ISMT_DESC_LPR 0x80 /* Large Packet Received */ 103 104 /* Macros */ 105 #define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw)) 106 107 /* iSMT General Register address offsets (SMBBAR + <addr>) */ 108 #define ISMT_GR_GCTRL 0x000 /* General Control */ 109 #define ISMT_GR_SMTICL 0x008 /* SMT Interrupt Cause Location */ 110 #define ISMT_GR_ERRINTMSK 0x010 /* Error Interrupt Mask */ 111 #define ISMT_GR_ERRAERMSK 0x014 /* Error AER Mask */ 112 #define ISMT_GR_ERRSTS 0x018 /* Error Status */ 113 #define ISMT_GR_ERRINFO 0x01c /* Error Information */ 114 115 /* iSMT Master Registers */ 116 #define ISMT_MSTR_MDBA 0x100 /* Master Descriptor Base Address */ 117 #define ISMT_MSTR_MCTRL 0x108 /* Master Control */ 118 #define ISMT_MSTR_MSTS 0x10c /* Master Status */ 119 #define ISMT_MSTR_MDS 0x110 /* Master Descriptor Size */ 120 #define ISMT_MSTR_RPOLICY 0x114 /* Retry Policy */ 121 122 /* iSMT Miscellaneous Registers */ 123 #define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */ 124 125 /* General Control Register (GCTRL) bit definitions */ 126 #define ISMT_GCTRL_TRST 0x04 /* Target Reset */ 127 #define ISMT_GCTRL_KILL 0x08 /* Kill */ 128 #define ISMT_GCTRL_SRST 0x40 /* Soft Reset */ 129 130 /* Master Control Register (MCTRL) bit definitions */ 131 #define ISMT_MCTRL_SS 0x01 /* Start/Stop */ 132 #define ISMT_MCTRL_MEIE 0x10 /* Master Error Interrupt Enable */ 133 #define ISMT_MCTRL_FMHP 0x00ff0000 /* Firmware Master Head Ptr (FMHP) */ 134 135 /* Master Status Register (MSTS) bit definitions */ 136 #define ISMT_MSTS_HMTP 0xff0000 /* HW Master Tail Pointer (HMTP) */ 137 #define ISMT_MSTS_MIS 0x20 /* Master Interrupt Status (MIS) */ 138 #define ISMT_MSTS_MEIS 0x10 /* Master Error Int Status (MEIS) */ 139 #define ISMT_MSTS_IP 0x01 /* In Progress */ 140 141 /* Master Descriptor Size (MDS) bit definitions */ 142 #define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */ 143 144 /* SMBus PHY Global Timing Register (SPGT) bit definitions */ 145 #define ISMT_SPGT_SPD_MASK 0xc0000000 /* SMBus Speed mask */ 146 #define ISMT_SPGT_SPD_80K 0x00 /* 80 kHz */ 147 #define ISMT_SPGT_SPD_100K (0x1 << 30) /* 100 kHz */ 148 #define ISMT_SPGT_SPD_400K (0x2 << 30) /* 400 kHz */ 149 #define ISMT_SPGT_SPD_1M (0x3 << 30) /* 1 MHz */ 150 151 152 /* MSI Control Register (MSICTL) bit definitions */ 153 #define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */ 154 155 /* iSMT Hardware Descriptor */ 156 struct ismt_desc { 157 u8 tgtaddr_rw; /* target address & r/w bit */ 158 u8 wr_len_cmd; /* write length in bytes or a command */ 159 u8 rd_len; /* read length */ 160 u8 control; /* control bits */ 161 u8 status; /* status bits */ 162 u8 retry; /* collision retry and retry count */ 163 u8 rxbytes; /* received bytes */ 164 u8 txbytes; /* transmitted bytes */ 165 u32 dptr_low; /* lower 32 bit of the data pointer */ 166 u32 dptr_high; /* upper 32 bit of the data pointer */ 167 } __packed; 168 169 struct ismt_priv { 170 struct i2c_adapter adapter; 171 void __iomem *smba; /* PCI BAR */ 172 struct pci_dev *pci_dev; 173 struct ismt_desc *hw; /* descriptor virt base addr */ 174 dma_addr_t io_rng_dma; /* descriptor HW base addr */ 175 u8 head; /* ring buffer head pointer */ 176 struct completion cmp; /* interrupt completion */ 177 u8 buffer[I2C_SMBUS_BLOCK_MAX + 16]; /* temp R/W data buffer */ 178 }; 179 180 static const struct pci_device_id ismt_ids[] = { 181 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) }, 182 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) }, 183 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMT) }, 184 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMT) }, 185 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EBG_SMT) }, 186 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) }, 187 { 0, } 188 }; 189 190 MODULE_DEVICE_TABLE(pci, ismt_ids); 191 192 /* Bus speed control bits for slow debuggers - refer to the docs for usage */ 193 static unsigned int bus_speed; 194 module_param(bus_speed, uint, S_IRUGO); 195 MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)"); 196 197 /** 198 * __ismt_desc_dump() - dump the contents of a specific descriptor 199 * @dev: the iSMT device 200 * @desc: the iSMT hardware descriptor 201 */ 202 static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc) 203 { 204 205 dev_dbg(dev, "Descriptor struct: %p\n", desc); 206 dev_dbg(dev, "\ttgtaddr_rw=0x%02X\n", desc->tgtaddr_rw); 207 dev_dbg(dev, "\twr_len_cmd=0x%02X\n", desc->wr_len_cmd); 208 dev_dbg(dev, "\trd_len= 0x%02X\n", desc->rd_len); 209 dev_dbg(dev, "\tcontrol= 0x%02X\n", desc->control); 210 dev_dbg(dev, "\tstatus= 0x%02X\n", desc->status); 211 dev_dbg(dev, "\tretry= 0x%02X\n", desc->retry); 212 dev_dbg(dev, "\trxbytes= 0x%02X\n", desc->rxbytes); 213 dev_dbg(dev, "\ttxbytes= 0x%02X\n", desc->txbytes); 214 dev_dbg(dev, "\tdptr_low= 0x%08X\n", desc->dptr_low); 215 dev_dbg(dev, "\tdptr_high= 0x%08X\n", desc->dptr_high); 216 } 217 /** 218 * ismt_desc_dump() - dump the contents of a descriptor for debug purposes 219 * @priv: iSMT private data 220 */ 221 static void ismt_desc_dump(struct ismt_priv *priv) 222 { 223 struct device *dev = &priv->pci_dev->dev; 224 struct ismt_desc *desc = &priv->hw[priv->head]; 225 226 dev_dbg(dev, "Dump of the descriptor struct: 0x%X\n", priv->head); 227 __ismt_desc_dump(dev, desc); 228 } 229 230 /** 231 * ismt_gen_reg_dump() - dump the iSMT General Registers 232 * @priv: iSMT private data 233 */ 234 static void ismt_gen_reg_dump(struct ismt_priv *priv) 235 { 236 struct device *dev = &priv->pci_dev->dev; 237 238 dev_dbg(dev, "Dump of the iSMT General Registers\n"); 239 dev_dbg(dev, " GCTRL.... : (0x%p)=0x%X\n", 240 priv->smba + ISMT_GR_GCTRL, 241 readl(priv->smba + ISMT_GR_GCTRL)); 242 dev_dbg(dev, " SMTICL... : (0x%p)=0x%016llX\n", 243 priv->smba + ISMT_GR_SMTICL, 244 (long long unsigned int)readq(priv->smba + ISMT_GR_SMTICL)); 245 dev_dbg(dev, " ERRINTMSK : (0x%p)=0x%X\n", 246 priv->smba + ISMT_GR_ERRINTMSK, 247 readl(priv->smba + ISMT_GR_ERRINTMSK)); 248 dev_dbg(dev, " ERRAERMSK : (0x%p)=0x%X\n", 249 priv->smba + ISMT_GR_ERRAERMSK, 250 readl(priv->smba + ISMT_GR_ERRAERMSK)); 251 dev_dbg(dev, " ERRSTS... : (0x%p)=0x%X\n", 252 priv->smba + ISMT_GR_ERRSTS, 253 readl(priv->smba + ISMT_GR_ERRSTS)); 254 dev_dbg(dev, " ERRINFO.. : (0x%p)=0x%X\n", 255 priv->smba + ISMT_GR_ERRINFO, 256 readl(priv->smba + ISMT_GR_ERRINFO)); 257 } 258 259 /** 260 * ismt_mstr_reg_dump() - dump the iSMT Master Registers 261 * @priv: iSMT private data 262 */ 263 static void ismt_mstr_reg_dump(struct ismt_priv *priv) 264 { 265 struct device *dev = &priv->pci_dev->dev; 266 267 dev_dbg(dev, "Dump of the iSMT Master Registers\n"); 268 dev_dbg(dev, " MDBA..... : (0x%p)=0x%016llX\n", 269 priv->smba + ISMT_MSTR_MDBA, 270 (long long unsigned int)readq(priv->smba + ISMT_MSTR_MDBA)); 271 dev_dbg(dev, " MCTRL.... : (0x%p)=0x%X\n", 272 priv->smba + ISMT_MSTR_MCTRL, 273 readl(priv->smba + ISMT_MSTR_MCTRL)); 274 dev_dbg(dev, " MSTS..... : (0x%p)=0x%X\n", 275 priv->smba + ISMT_MSTR_MSTS, 276 readl(priv->smba + ISMT_MSTR_MSTS)); 277 dev_dbg(dev, " MDS...... : (0x%p)=0x%X\n", 278 priv->smba + ISMT_MSTR_MDS, 279 readl(priv->smba + ISMT_MSTR_MDS)); 280 dev_dbg(dev, " RPOLICY.. : (0x%p)=0x%X\n", 281 priv->smba + ISMT_MSTR_RPOLICY, 282 readl(priv->smba + ISMT_MSTR_RPOLICY)); 283 dev_dbg(dev, " SPGT..... : (0x%p)=0x%X\n", 284 priv->smba + ISMT_SPGT, 285 readl(priv->smba + ISMT_SPGT)); 286 } 287 288 /** 289 * ismt_submit_desc() - add a descriptor to the ring 290 * @priv: iSMT private data 291 */ 292 static void ismt_submit_desc(struct ismt_priv *priv) 293 { 294 uint fmhp; 295 uint val; 296 297 ismt_desc_dump(priv); 298 ismt_gen_reg_dump(priv); 299 ismt_mstr_reg_dump(priv); 300 301 /* Set the FMHP (Firmware Master Head Pointer)*/ 302 fmhp = ((priv->head + 1) % ISMT_DESC_ENTRIES) << 16; 303 val = readl(priv->smba + ISMT_MSTR_MCTRL); 304 writel((val & ~ISMT_MCTRL_FMHP) | fmhp, 305 priv->smba + ISMT_MSTR_MCTRL); 306 307 /* Set the start bit */ 308 val = readl(priv->smba + ISMT_MSTR_MCTRL); 309 writel(val | ISMT_MCTRL_SS, 310 priv->smba + ISMT_MSTR_MCTRL); 311 } 312 313 /** 314 * ismt_process_desc() - handle the completion of the descriptor 315 * @desc: the iSMT hardware descriptor 316 * @data: data buffer from the upper layer 317 * @priv: ismt_priv struct holding our dma buffer 318 * @size: SMBus transaction type 319 * @read_write: flag to indicate if this is a read or write 320 */ 321 static int ismt_process_desc(const struct ismt_desc *desc, 322 union i2c_smbus_data *data, 323 struct ismt_priv *priv, int size, 324 char read_write) 325 { 326 u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); 327 328 dev_dbg(&priv->pci_dev->dev, "Processing completed descriptor\n"); 329 __ismt_desc_dump(&priv->pci_dev->dev, desc); 330 ismt_gen_reg_dump(priv); 331 ismt_mstr_reg_dump(priv); 332 333 if (desc->status & ISMT_DESC_SCS) { 334 if (read_write == I2C_SMBUS_WRITE && 335 size != I2C_SMBUS_PROC_CALL && 336 size != I2C_SMBUS_BLOCK_PROC_CALL) 337 return 0; 338 339 switch (size) { 340 case I2C_SMBUS_BYTE: 341 case I2C_SMBUS_BYTE_DATA: 342 data->byte = dma_buffer[0]; 343 break; 344 case I2C_SMBUS_WORD_DATA: 345 case I2C_SMBUS_PROC_CALL: 346 data->word = dma_buffer[0] | (dma_buffer[1] << 8); 347 break; 348 case I2C_SMBUS_BLOCK_DATA: 349 case I2C_SMBUS_BLOCK_PROC_CALL: 350 if (desc->rxbytes != dma_buffer[0] + 1) 351 return -EMSGSIZE; 352 353 memcpy(data->block, dma_buffer, desc->rxbytes); 354 break; 355 case I2C_SMBUS_I2C_BLOCK_DATA: 356 memcpy(&data->block[1], dma_buffer, desc->rxbytes); 357 data->block[0] = desc->rxbytes; 358 break; 359 } 360 return 0; 361 } 362 363 if (likely(desc->status & ISMT_DESC_NAK)) 364 return -ENXIO; 365 366 if (desc->status & ISMT_DESC_CRC) 367 return -EBADMSG; 368 369 if (desc->status & ISMT_DESC_COL) 370 return -EAGAIN; 371 372 if (desc->status & ISMT_DESC_LPR) 373 return -EPROTO; 374 375 if (desc->status & (ISMT_DESC_DLTO | ISMT_DESC_CLTO)) 376 return -ETIMEDOUT; 377 378 return -EIO; 379 } 380 381 /** 382 * ismt_access() - process an SMBus command 383 * @adap: the i2c host adapter 384 * @addr: address of the i2c/SMBus target 385 * @flags: command options 386 * @read_write: read from or write to device 387 * @command: the i2c/SMBus command to issue 388 * @size: SMBus transaction type 389 * @data: read/write data buffer 390 */ 391 static int ismt_access(struct i2c_adapter *adap, u16 addr, 392 unsigned short flags, char read_write, u8 command, 393 int size, union i2c_smbus_data *data) 394 { 395 int ret; 396 unsigned long time_left; 397 dma_addr_t dma_addr = 0; /* address of the data buffer */ 398 u8 dma_size = 0; 399 enum dma_data_direction dma_direction = 0; 400 struct ismt_desc *desc; 401 struct ismt_priv *priv = i2c_get_adapdata(adap); 402 struct device *dev = &priv->pci_dev->dev; 403 u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); 404 405 desc = &priv->hw[priv->head]; 406 407 /* Initialize the DMA buffer */ 408 memset(priv->buffer, 0, sizeof(priv->buffer)); 409 410 /* Initialize the descriptor */ 411 memset(desc, 0, sizeof(struct ismt_desc)); 412 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); 413 414 /* Initialize common control bits */ 415 if (likely(pci_dev_msi_enabled(priv->pci_dev))) 416 desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR; 417 else 418 desc->control = ISMT_DESC_FAIR; 419 420 if ((flags & I2C_CLIENT_PEC) && (size != I2C_SMBUS_QUICK) 421 && (size != I2C_SMBUS_I2C_BLOCK_DATA)) 422 desc->control |= ISMT_DESC_PEC; 423 424 switch (size) { 425 case I2C_SMBUS_QUICK: 426 dev_dbg(dev, "I2C_SMBUS_QUICK\n"); 427 break; 428 429 case I2C_SMBUS_BYTE: 430 if (read_write == I2C_SMBUS_WRITE) { 431 /* 432 * Send Byte 433 * The command field contains the write data 434 */ 435 dev_dbg(dev, "I2C_SMBUS_BYTE: WRITE\n"); 436 desc->control |= ISMT_DESC_CWRL; 437 desc->wr_len_cmd = command; 438 } else { 439 /* Receive Byte */ 440 dev_dbg(dev, "I2C_SMBUS_BYTE: READ\n"); 441 dma_size = 1; 442 dma_direction = DMA_FROM_DEVICE; 443 desc->rd_len = 1; 444 } 445 break; 446 447 case I2C_SMBUS_BYTE_DATA: 448 if (read_write == I2C_SMBUS_WRITE) { 449 /* 450 * Write Byte 451 * Command plus 1 data byte 452 */ 453 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: WRITE\n"); 454 desc->wr_len_cmd = 2; 455 dma_size = 2; 456 dma_direction = DMA_TO_DEVICE; 457 dma_buffer[0] = command; 458 dma_buffer[1] = data->byte; 459 } else { 460 /* Read Byte */ 461 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: READ\n"); 462 desc->control |= ISMT_DESC_CWRL; 463 desc->wr_len_cmd = command; 464 desc->rd_len = 1; 465 dma_size = 1; 466 dma_direction = DMA_FROM_DEVICE; 467 } 468 break; 469 470 case I2C_SMBUS_WORD_DATA: 471 if (read_write == I2C_SMBUS_WRITE) { 472 /* Write Word */ 473 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: WRITE\n"); 474 desc->wr_len_cmd = 3; 475 dma_size = 3; 476 dma_direction = DMA_TO_DEVICE; 477 dma_buffer[0] = command; 478 dma_buffer[1] = data->word & 0xff; 479 dma_buffer[2] = data->word >> 8; 480 } else { 481 /* Read Word */ 482 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: READ\n"); 483 desc->wr_len_cmd = command; 484 desc->control |= ISMT_DESC_CWRL; 485 desc->rd_len = 2; 486 dma_size = 2; 487 dma_direction = DMA_FROM_DEVICE; 488 } 489 break; 490 491 case I2C_SMBUS_PROC_CALL: 492 dev_dbg(dev, "I2C_SMBUS_PROC_CALL\n"); 493 desc->wr_len_cmd = 3; 494 desc->rd_len = 2; 495 dma_size = 3; 496 dma_direction = DMA_BIDIRECTIONAL; 497 dma_buffer[0] = command; 498 dma_buffer[1] = data->word & 0xff; 499 dma_buffer[2] = data->word >> 8; 500 break; 501 502 case I2C_SMBUS_BLOCK_DATA: 503 if (read_write == I2C_SMBUS_WRITE) { 504 /* Block Write */ 505 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: WRITE\n"); 506 dma_size = data->block[0] + 1; 507 dma_direction = DMA_TO_DEVICE; 508 desc->wr_len_cmd = dma_size; 509 desc->control |= ISMT_DESC_BLK; 510 dma_buffer[0] = command; 511 memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); 512 } else { 513 /* Block Read */ 514 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n"); 515 dma_size = I2C_SMBUS_BLOCK_MAX; 516 dma_direction = DMA_FROM_DEVICE; 517 desc->rd_len = dma_size; 518 desc->wr_len_cmd = command; 519 desc->control |= (ISMT_DESC_BLK | ISMT_DESC_CWRL); 520 } 521 break; 522 523 case I2C_SMBUS_BLOCK_PROC_CALL: 524 dev_dbg(dev, "I2C_SMBUS_BLOCK_PROC_CALL\n"); 525 dma_size = I2C_SMBUS_BLOCK_MAX; 526 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 1); 527 desc->wr_len_cmd = data->block[0] + 1; 528 desc->rd_len = dma_size; 529 desc->control |= ISMT_DESC_BLK; 530 dma_direction = DMA_BIDIRECTIONAL; 531 dma_buffer[0] = command; 532 memcpy(&dma_buffer[1], &data->block[1], data->block[0]); 533 break; 534 535 case I2C_SMBUS_I2C_BLOCK_DATA: 536 /* Make sure the length is valid */ 537 if (data->block[0] < 1) 538 data->block[0] = 1; 539 540 if (data->block[0] > I2C_SMBUS_BLOCK_MAX) 541 data->block[0] = I2C_SMBUS_BLOCK_MAX; 542 543 if (read_write == I2C_SMBUS_WRITE) { 544 /* i2c Block Write */ 545 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n"); 546 dma_size = data->block[0] + 1; 547 dma_direction = DMA_TO_DEVICE; 548 desc->wr_len_cmd = dma_size; 549 desc->control |= ISMT_DESC_I2C; 550 dma_buffer[0] = command; 551 memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); 552 } else { 553 /* i2c Block Read */ 554 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n"); 555 dma_size = data->block[0]; 556 dma_direction = DMA_FROM_DEVICE; 557 desc->rd_len = dma_size; 558 desc->wr_len_cmd = command; 559 desc->control |= (ISMT_DESC_I2C | ISMT_DESC_CWRL); 560 /* 561 * Per the "Table 15-15. I2C Commands", 562 * in the External Design Specification (EDS), 563 * (Document Number: 508084, Revision: 2.0), 564 * the _rw bit must be 0 565 */ 566 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 0); 567 } 568 break; 569 570 default: 571 dev_err(dev, "Unsupported transaction %d\n", 572 size); 573 return -EOPNOTSUPP; 574 } 575 576 /* map the data buffer */ 577 if (dma_size != 0) { 578 dev_dbg(dev, " dev=%p\n", dev); 579 dev_dbg(dev, " data=%p\n", data); 580 dev_dbg(dev, " dma_buffer=%p\n", dma_buffer); 581 dev_dbg(dev, " dma_size=%d\n", dma_size); 582 dev_dbg(dev, " dma_direction=%d\n", dma_direction); 583 584 dma_addr = dma_map_single(dev, 585 dma_buffer, 586 dma_size, 587 dma_direction); 588 589 if (dma_mapping_error(dev, dma_addr)) { 590 dev_err(dev, "Error in mapping dma buffer %p\n", 591 dma_buffer); 592 return -EIO; 593 } 594 595 dev_dbg(dev, " dma_addr = %pad\n", &dma_addr); 596 597 desc->dptr_low = lower_32_bits(dma_addr); 598 desc->dptr_high = upper_32_bits(dma_addr); 599 } 600 601 reinit_completion(&priv->cmp); 602 603 /* Add the descriptor */ 604 ismt_submit_desc(priv); 605 606 /* Now we wait for interrupt completion, 1s */ 607 time_left = wait_for_completion_timeout(&priv->cmp, HZ*1); 608 609 /* unmap the data buffer */ 610 if (dma_size != 0) 611 dma_unmap_single(dev, dma_addr, dma_size, dma_direction); 612 613 if (unlikely(!time_left)) { 614 dev_err(dev, "completion wait timed out\n"); 615 ret = -ETIMEDOUT; 616 goto out; 617 } 618 619 /* do any post processing of the descriptor here */ 620 ret = ismt_process_desc(desc, data, priv, size, read_write); 621 622 out: 623 /* Update the ring pointer */ 624 priv->head++; 625 priv->head %= ISMT_DESC_ENTRIES; 626 627 return ret; 628 } 629 630 /** 631 * ismt_func() - report which i2c commands are supported by this adapter 632 * @adap: the i2c host adapter 633 */ 634 static u32 ismt_func(struct i2c_adapter *adap) 635 { 636 return I2C_FUNC_SMBUS_QUICK | 637 I2C_FUNC_SMBUS_BYTE | 638 I2C_FUNC_SMBUS_BYTE_DATA | 639 I2C_FUNC_SMBUS_WORD_DATA | 640 I2C_FUNC_SMBUS_PROC_CALL | 641 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 642 I2C_FUNC_SMBUS_BLOCK_DATA | 643 I2C_FUNC_SMBUS_I2C_BLOCK | 644 I2C_FUNC_SMBUS_PEC; 645 } 646 647 static const struct i2c_algorithm smbus_algorithm = { 648 .smbus_xfer = ismt_access, 649 .functionality = ismt_func, 650 }; 651 652 /** 653 * ismt_handle_isr() - interrupt handler bottom half 654 * @priv: iSMT private data 655 */ 656 static irqreturn_t ismt_handle_isr(struct ismt_priv *priv) 657 { 658 complete(&priv->cmp); 659 660 return IRQ_HANDLED; 661 } 662 663 664 /** 665 * ismt_do_interrupt() - IRQ interrupt handler 666 * @vec: interrupt vector 667 * @data: iSMT private data 668 */ 669 static irqreturn_t ismt_do_interrupt(int vec, void *data) 670 { 671 u32 val; 672 struct ismt_priv *priv = data; 673 674 /* 675 * check to see it's our interrupt, return IRQ_NONE if not ours 676 * since we are sharing interrupt 677 */ 678 val = readl(priv->smba + ISMT_MSTR_MSTS); 679 680 if (!(val & (ISMT_MSTS_MIS | ISMT_MSTS_MEIS))) 681 return IRQ_NONE; 682 else 683 writel(val | ISMT_MSTS_MIS | ISMT_MSTS_MEIS, 684 priv->smba + ISMT_MSTR_MSTS); 685 686 return ismt_handle_isr(priv); 687 } 688 689 /** 690 * ismt_do_msi_interrupt() - MSI interrupt handler 691 * @vec: interrupt vector 692 * @data: iSMT private data 693 */ 694 static irqreturn_t ismt_do_msi_interrupt(int vec, void *data) 695 { 696 return ismt_handle_isr(data); 697 } 698 699 /** 700 * ismt_hw_init() - initialize the iSMT hardware 701 * @priv: iSMT private data 702 */ 703 static void ismt_hw_init(struct ismt_priv *priv) 704 { 705 u32 val; 706 struct device *dev = &priv->pci_dev->dev; 707 708 /* initialize the Master Descriptor Base Address (MDBA) */ 709 writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); 710 711 /* initialize the Master Control Register (MCTRL) */ 712 writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL); 713 714 /* initialize the Master Status Register (MSTS) */ 715 writel(0, priv->smba + ISMT_MSTR_MSTS); 716 717 /* initialize the Master Descriptor Size (MDS) */ 718 val = readl(priv->smba + ISMT_MSTR_MDS); 719 writel((val & ~ISMT_MDS_MASK) | (ISMT_DESC_ENTRIES - 1), 720 priv->smba + ISMT_MSTR_MDS); 721 722 /* 723 * Set the SMBus speed (could use this for slow HW debuggers) 724 */ 725 726 val = readl(priv->smba + ISMT_SPGT); 727 728 switch (bus_speed) { 729 case 0: 730 break; 731 732 case 80: 733 dev_dbg(dev, "Setting SMBus clock to 80 kHz\n"); 734 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_80K), 735 priv->smba + ISMT_SPGT); 736 break; 737 738 case 100: 739 dev_dbg(dev, "Setting SMBus clock to 100 kHz\n"); 740 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_100K), 741 priv->smba + ISMT_SPGT); 742 break; 743 744 case 400: 745 dev_dbg(dev, "Setting SMBus clock to 400 kHz\n"); 746 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_400K), 747 priv->smba + ISMT_SPGT); 748 break; 749 750 case 1000: 751 dev_dbg(dev, "Setting SMBus clock to 1000 kHz\n"); 752 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_1M), 753 priv->smba + ISMT_SPGT); 754 break; 755 756 default: 757 dev_warn(dev, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n"); 758 break; 759 } 760 761 val = readl(priv->smba + ISMT_SPGT); 762 763 switch (val & ISMT_SPGT_SPD_MASK) { 764 case ISMT_SPGT_SPD_80K: 765 bus_speed = 80; 766 break; 767 case ISMT_SPGT_SPD_100K: 768 bus_speed = 100; 769 break; 770 case ISMT_SPGT_SPD_400K: 771 bus_speed = 400; 772 break; 773 case ISMT_SPGT_SPD_1M: 774 bus_speed = 1000; 775 break; 776 } 777 dev_dbg(dev, "SMBus clock is running at %d kHz\n", bus_speed); 778 } 779 780 /** 781 * ismt_dev_init() - initialize the iSMT data structures 782 * @priv: iSMT private data 783 */ 784 static int ismt_dev_init(struct ismt_priv *priv) 785 { 786 /* allocate memory for the descriptor */ 787 priv->hw = dmam_alloc_coherent(&priv->pci_dev->dev, 788 (ISMT_DESC_ENTRIES 789 * sizeof(struct ismt_desc)), 790 &priv->io_rng_dma, 791 GFP_KERNEL); 792 if (!priv->hw) 793 return -ENOMEM; 794 795 priv->head = 0; 796 init_completion(&priv->cmp); 797 798 return 0; 799 } 800 801 /** 802 * ismt_int_init() - initialize interrupts 803 * @priv: iSMT private data 804 */ 805 static int ismt_int_init(struct ismt_priv *priv) 806 { 807 int err; 808 809 /* Try using MSI interrupts */ 810 err = pci_enable_msi(priv->pci_dev); 811 if (err) 812 goto intx; 813 814 err = devm_request_irq(&priv->pci_dev->dev, 815 priv->pci_dev->irq, 816 ismt_do_msi_interrupt, 817 0, 818 "ismt-msi", 819 priv); 820 if (err) { 821 pci_disable_msi(priv->pci_dev); 822 goto intx; 823 } 824 825 return 0; 826 827 /* Try using legacy interrupts */ 828 intx: 829 dev_warn(&priv->pci_dev->dev, 830 "Unable to use MSI interrupts, falling back to legacy\n"); 831 832 err = devm_request_irq(&priv->pci_dev->dev, 833 priv->pci_dev->irq, 834 ismt_do_interrupt, 835 IRQF_SHARED, 836 "ismt-intx", 837 priv); 838 if (err) { 839 dev_err(&priv->pci_dev->dev, "no usable interrupts\n"); 840 return err; 841 } 842 843 return 0; 844 } 845 846 static struct pci_driver ismt_driver; 847 848 /** 849 * ismt_probe() - probe for iSMT devices 850 * @pdev: PCI-Express device 851 * @id: PCI-Express device ID 852 */ 853 static int 854 ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id) 855 { 856 int err; 857 struct ismt_priv *priv; 858 unsigned long start, len; 859 860 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 861 if (!priv) 862 return -ENOMEM; 863 864 pci_set_drvdata(pdev, priv); 865 866 i2c_set_adapdata(&priv->adapter, priv); 867 priv->adapter.owner = THIS_MODULE; 868 priv->adapter.class = I2C_CLASS_HWMON; 869 priv->adapter.algo = &smbus_algorithm; 870 priv->adapter.dev.parent = &pdev->dev; 871 ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev)); 872 priv->adapter.retries = ISMT_MAX_RETRIES; 873 874 priv->pci_dev = pdev; 875 876 err = pcim_enable_device(pdev); 877 if (err) { 878 dev_err(&pdev->dev, "Failed to enable SMBus PCI device (%d)\n", 879 err); 880 return err; 881 } 882 883 /* enable bus mastering */ 884 pci_set_master(pdev); 885 886 /* Determine the address of the SMBus area */ 887 start = pci_resource_start(pdev, SMBBAR); 888 len = pci_resource_len(pdev, SMBBAR); 889 if (!start || !len) { 890 dev_err(&pdev->dev, 891 "SMBus base address uninitialized, upgrade BIOS\n"); 892 return -ENODEV; 893 } 894 895 snprintf(priv->adapter.name, sizeof(priv->adapter.name), 896 "SMBus iSMT adapter at %lx", start); 897 898 dev_dbg(&priv->pci_dev->dev, " start=0x%lX\n", start); 899 dev_dbg(&priv->pci_dev->dev, " len=0x%lX\n", len); 900 901 err = acpi_check_resource_conflict(&pdev->resource[SMBBAR]); 902 if (err) { 903 dev_err(&pdev->dev, "ACPI resource conflict!\n"); 904 return err; 905 } 906 907 err = pci_request_region(pdev, SMBBAR, ismt_driver.name); 908 if (err) { 909 dev_err(&pdev->dev, 910 "Failed to request SMBus region 0x%lx-0x%lx\n", 911 start, start + len); 912 return err; 913 } 914 915 priv->smba = pcim_iomap(pdev, SMBBAR, len); 916 if (!priv->smba) { 917 dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n"); 918 return -ENODEV; 919 } 920 921 if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) != 0) || 922 (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) != 0)) { 923 if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) != 0) || 924 (pci_set_consistent_dma_mask(pdev, 925 DMA_BIT_MASK(32)) != 0)) { 926 dev_err(&pdev->dev, "pci_set_dma_mask fail %p\n", 927 pdev); 928 return -ENODEV; 929 } 930 } 931 932 err = ismt_dev_init(priv); 933 if (err) 934 return err; 935 936 ismt_hw_init(priv); 937 938 err = ismt_int_init(priv); 939 if (err) 940 return err; 941 942 err = i2c_add_adapter(&priv->adapter); 943 if (err) 944 return -ENODEV; 945 return 0; 946 } 947 948 /** 949 * ismt_remove() - release driver resources 950 * @pdev: PCI-Express device 951 */ 952 static void ismt_remove(struct pci_dev *pdev) 953 { 954 struct ismt_priv *priv = pci_get_drvdata(pdev); 955 956 i2c_del_adapter(&priv->adapter); 957 } 958 959 static struct pci_driver ismt_driver = { 960 .name = "ismt_smbus", 961 .id_table = ismt_ids, 962 .probe = ismt_probe, 963 .remove = ismt_remove, 964 }; 965 966 module_pci_driver(ismt_driver); 967 968 MODULE_LICENSE("Dual BSD/GPL"); 969 MODULE_AUTHOR("Bill E. Brown <bill.e.brown@intel.com>"); 970 MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver"); 971