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#define ISMT_LOG_ENTRIES 3 /* number of interrupt cause log entries */ 86 87/* Hardware Descriptor Constants - Control Field */ 88#define ISMT_DESC_CWRL 0x01 /* Command/Write Length */ 89#define ISMT_DESC_BLK 0X04 /* Perform Block Transaction */ 90#define ISMT_DESC_FAIR 0x08 /* Set fairness flag upon successful arbit. */ 91#define ISMT_DESC_PEC 0x10 /* Packet Error Code */ 92#define ISMT_DESC_I2C 0x20 /* I2C Enable */ 93#define ISMT_DESC_INT 0x40 /* Interrupt */ 94#define ISMT_DESC_SOE 0x80 /* Stop On Error */ 95 96/* Hardware Descriptor Constants - Status Field */ 97#define ISMT_DESC_SCS 0x01 /* Success */ 98#define ISMT_DESC_DLTO 0x04 /* Data Low Time Out */ 99#define ISMT_DESC_NAK 0x08 /* NAK Received */ 100#define ISMT_DESC_CRC 0x10 /* CRC Error */ 101#define ISMT_DESC_CLTO 0x20 /* Clock Low Time Out */ 102#define ISMT_DESC_COL 0x40 /* Collisions */ 103#define ISMT_DESC_LPR 0x80 /* Large Packet Received */ 104 105/* Macros */ 106#define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw)) 107 108/* iSMT General Register address offsets (SMBBAR + <addr>) */ 109#define ISMT_GR_GCTRL 0x000 /* General Control */ 110#define ISMT_GR_SMTICL 0x008 /* SMT Interrupt Cause Location */ 111#define ISMT_GR_ERRINTMSK 0x010 /* Error Interrupt Mask */ 112#define ISMT_GR_ERRAERMSK 0x014 /* Error AER Mask */ 113#define ISMT_GR_ERRSTS 0x018 /* Error Status */ 114#define ISMT_GR_ERRINFO 0x01c /* Error Information */ 115 116/* iSMT Master Registers */ 117#define ISMT_MSTR_MDBA 0x100 /* Master Descriptor Base Address */ 118#define ISMT_MSTR_MCTRL 0x108 /* Master Control */ 119#define ISMT_MSTR_MSTS 0x10c /* Master Status */ 120#define ISMT_MSTR_MDS 0x110 /* Master Descriptor Size */ 121#define ISMT_MSTR_RPOLICY 0x114 /* Retry Policy */ 122 123/* iSMT Miscellaneous Registers */ 124#define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */ 125 126/* General Control Register (GCTRL) bit definitions */ 127#define ISMT_GCTRL_TRST 0x04 /* Target Reset */ 128#define ISMT_GCTRL_KILL 0x08 /* Kill */ 129#define ISMT_GCTRL_SRST 0x40 /* Soft Reset */ 130 131/* Master Control Register (MCTRL) bit definitions */ 132#define ISMT_MCTRL_SS 0x01 /* Start/Stop */ 133#define ISMT_MCTRL_MEIE 0x10 /* Master Error Interrupt Enable */ 134#define ISMT_MCTRL_FMHP 0x00ff0000 /* Firmware Master Head Ptr (FMHP) */ 135 136/* Master Status Register (MSTS) bit definitions */ 137#define ISMT_MSTS_HMTP 0xff0000 /* HW Master Tail Pointer (HMTP) */ 138#define ISMT_MSTS_MIS 0x20 /* Master Interrupt Status (MIS) */ 139#define ISMT_MSTS_MEIS 0x10 /* Master Error Int Status (MEIS) */ 140#define ISMT_MSTS_IP 0x01 /* In Progress */ 141 142/* Master Descriptor Size (MDS) bit definitions */ 143#define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */ 144 145/* SMBus PHY Global Timing Register (SPGT) bit definitions */ 146#define ISMT_SPGT_SPD_MASK 0xc0000000 /* SMBus Speed mask */ 147#define ISMT_SPGT_SPD_80K 0x00 /* 80 kHz */ 148#define ISMT_SPGT_SPD_100K (0x1 << 30) /* 100 kHz */ 149#define ISMT_SPGT_SPD_400K (0x2U << 30) /* 400 kHz */ 150#define ISMT_SPGT_SPD_1M (0x3U << 30) /* 1 MHz */ 151 152 153/* MSI Control Register (MSICTL) bit definitions */ 154#define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */ 155 156/* iSMT Hardware Descriptor */ 157struct ismt_desc { 158 u8 tgtaddr_rw; /* target address & r/w bit */ 159 u8 wr_len_cmd; /* write length in bytes or a command */ 160 u8 rd_len; /* read length */ 161 u8 control; /* control bits */ 162 u8 status; /* status bits */ 163 u8 retry; /* collision retry and retry count */ 164 u8 rxbytes; /* received bytes */ 165 u8 txbytes; /* transmitted bytes */ 166 u32 dptr_low; /* lower 32 bit of the data pointer */ 167 u32 dptr_high; /* upper 32 bit of the data pointer */ 168} __packed; 169 170struct ismt_priv { 171 struct i2c_adapter adapter; 172 void __iomem *smba; /* PCI BAR */ 173 struct pci_dev *pci_dev; 174 struct ismt_desc *hw; /* descriptor virt base addr */ 175 dma_addr_t io_rng_dma; /* descriptor HW base addr */ 176 u8 head; /* ring buffer head pointer */ 177 struct completion cmp; /* interrupt completion */ 178 u8 buffer[I2C_SMBUS_BLOCK_MAX + 16]; /* temp R/W data buffer */ 179 dma_addr_t log_dma; 180 u32 *log; 181}; 182 183static const struct pci_device_id ismt_ids[] = { 184 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) }, 185 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) }, 186 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMT) }, 187 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMT) }, 188 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EBG_SMT) }, 189 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) }, 190 { 0, } 191}; 192 193MODULE_DEVICE_TABLE(pci, ismt_ids); 194 195/* Bus speed control bits for slow debuggers - refer to the docs for usage */ 196static unsigned int bus_speed; 197module_param(bus_speed, uint, S_IRUGO); 198MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)"); 199 200/** 201 * __ismt_desc_dump() - dump the contents of a specific descriptor 202 * @dev: the iSMT device 203 * @desc: the iSMT hardware descriptor 204 */ 205static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc) 206{ 207 208 dev_dbg(dev, "Descriptor struct: %p\n", desc); 209 dev_dbg(dev, "\ttgtaddr_rw=0x%02X\n", desc->tgtaddr_rw); 210 dev_dbg(dev, "\twr_len_cmd=0x%02X\n", desc->wr_len_cmd); 211 dev_dbg(dev, "\trd_len= 0x%02X\n", desc->rd_len); 212 dev_dbg(dev, "\tcontrol= 0x%02X\n", desc->control); 213 dev_dbg(dev, "\tstatus= 0x%02X\n", desc->status); 214 dev_dbg(dev, "\tretry= 0x%02X\n", desc->retry); 215 dev_dbg(dev, "\trxbytes= 0x%02X\n", desc->rxbytes); 216 dev_dbg(dev, "\ttxbytes= 0x%02X\n", desc->txbytes); 217 dev_dbg(dev, "\tdptr_low= 0x%08X\n", desc->dptr_low); 218 dev_dbg(dev, "\tdptr_high= 0x%08X\n", desc->dptr_high); 219} 220/** 221 * ismt_desc_dump() - dump the contents of a descriptor for debug purposes 222 * @priv: iSMT private data 223 */ 224static void ismt_desc_dump(struct ismt_priv *priv) 225{ 226 struct device *dev = &priv->pci_dev->dev; 227 struct ismt_desc *desc = &priv->hw[priv->head]; 228 229 dev_dbg(dev, "Dump of the descriptor struct: 0x%X\n", priv->head); 230 __ismt_desc_dump(dev, desc); 231} 232 233/** 234 * ismt_gen_reg_dump() - dump the iSMT General Registers 235 * @priv: iSMT private data 236 */ 237static void ismt_gen_reg_dump(struct ismt_priv *priv) 238{ 239 struct device *dev = &priv->pci_dev->dev; 240 241 dev_dbg(dev, "Dump of the iSMT General Registers\n"); 242 dev_dbg(dev, " GCTRL.... : (0x%p)=0x%X\n", 243 priv->smba + ISMT_GR_GCTRL, 244 readl(priv->smba + ISMT_GR_GCTRL)); 245 dev_dbg(dev, " SMTICL... : (0x%p)=0x%016llX\n", 246 priv->smba + ISMT_GR_SMTICL, 247 (long long unsigned int)readq(priv->smba + ISMT_GR_SMTICL)); 248 dev_dbg(dev, " ERRINTMSK : (0x%p)=0x%X\n", 249 priv->smba + ISMT_GR_ERRINTMSK, 250 readl(priv->smba + ISMT_GR_ERRINTMSK)); 251 dev_dbg(dev, " ERRAERMSK : (0x%p)=0x%X\n", 252 priv->smba + ISMT_GR_ERRAERMSK, 253 readl(priv->smba + ISMT_GR_ERRAERMSK)); 254 dev_dbg(dev, " ERRSTS... : (0x%p)=0x%X\n", 255 priv->smba + ISMT_GR_ERRSTS, 256 readl(priv->smba + ISMT_GR_ERRSTS)); 257 dev_dbg(dev, " ERRINFO.. : (0x%p)=0x%X\n", 258 priv->smba + ISMT_GR_ERRINFO, 259 readl(priv->smba + ISMT_GR_ERRINFO)); 260} 261 262/** 263 * ismt_mstr_reg_dump() - dump the iSMT Master Registers 264 * @priv: iSMT private data 265 */ 266static void ismt_mstr_reg_dump(struct ismt_priv *priv) 267{ 268 struct device *dev = &priv->pci_dev->dev; 269 270 dev_dbg(dev, "Dump of the iSMT Master Registers\n"); 271 dev_dbg(dev, " MDBA..... : (0x%p)=0x%016llX\n", 272 priv->smba + ISMT_MSTR_MDBA, 273 (long long unsigned int)readq(priv->smba + ISMT_MSTR_MDBA)); 274 dev_dbg(dev, " MCTRL.... : (0x%p)=0x%X\n", 275 priv->smba + ISMT_MSTR_MCTRL, 276 readl(priv->smba + ISMT_MSTR_MCTRL)); 277 dev_dbg(dev, " MSTS..... : (0x%p)=0x%X\n", 278 priv->smba + ISMT_MSTR_MSTS, 279 readl(priv->smba + ISMT_MSTR_MSTS)); 280 dev_dbg(dev, " MDS...... : (0x%p)=0x%X\n", 281 priv->smba + ISMT_MSTR_MDS, 282 readl(priv->smba + ISMT_MSTR_MDS)); 283 dev_dbg(dev, " RPOLICY.. : (0x%p)=0x%X\n", 284 priv->smba + ISMT_MSTR_RPOLICY, 285 readl(priv->smba + ISMT_MSTR_RPOLICY)); 286 dev_dbg(dev, " SPGT..... : (0x%p)=0x%X\n", 287 priv->smba + ISMT_SPGT, 288 readl(priv->smba + ISMT_SPGT)); 289} 290 291/** 292 * ismt_submit_desc() - add a descriptor to the ring 293 * @priv: iSMT private data 294 */ 295static void ismt_submit_desc(struct ismt_priv *priv) 296{ 297 uint fmhp; 298 uint val; 299 300 ismt_desc_dump(priv); 301 ismt_gen_reg_dump(priv); 302 ismt_mstr_reg_dump(priv); 303 304 /* Set the FMHP (Firmware Master Head Pointer)*/ 305 fmhp = ((priv->head + 1) % ISMT_DESC_ENTRIES) << 16; 306 val = readl(priv->smba + ISMT_MSTR_MCTRL); 307 writel((val & ~ISMT_MCTRL_FMHP) | fmhp, 308 priv->smba + ISMT_MSTR_MCTRL); 309 310 /* Set the start bit */ 311 val = readl(priv->smba + ISMT_MSTR_MCTRL); 312 writel(val | ISMT_MCTRL_SS, 313 priv->smba + ISMT_MSTR_MCTRL); 314} 315 316/** 317 * ismt_process_desc() - handle the completion of the descriptor 318 * @desc: the iSMT hardware descriptor 319 * @data: data buffer from the upper layer 320 * @priv: ismt_priv struct holding our dma buffer 321 * @size: SMBus transaction type 322 * @read_write: flag to indicate if this is a read or write 323 */ 324static int ismt_process_desc(const struct ismt_desc *desc, 325 union i2c_smbus_data *data, 326 struct ismt_priv *priv, int size, 327 char read_write) 328{ 329 u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); 330 331 dev_dbg(&priv->pci_dev->dev, "Processing completed descriptor\n"); 332 __ismt_desc_dump(&priv->pci_dev->dev, desc); 333 ismt_gen_reg_dump(priv); 334 ismt_mstr_reg_dump(priv); 335 336 if (desc->status & ISMT_DESC_SCS) { 337 if (read_write == I2C_SMBUS_WRITE && 338 size != I2C_SMBUS_PROC_CALL && 339 size != I2C_SMBUS_BLOCK_PROC_CALL) 340 return 0; 341 342 switch (size) { 343 case I2C_SMBUS_BYTE: 344 case I2C_SMBUS_BYTE_DATA: 345 data->byte = dma_buffer[0]; 346 break; 347 case I2C_SMBUS_WORD_DATA: 348 case I2C_SMBUS_PROC_CALL: 349 data->word = dma_buffer[0] | (dma_buffer[1] << 8); 350 break; 351 case I2C_SMBUS_BLOCK_DATA: 352 case I2C_SMBUS_BLOCK_PROC_CALL: 353 if (desc->rxbytes != dma_buffer[0] + 1) 354 return -EMSGSIZE; 355 356 memcpy(data->block, dma_buffer, desc->rxbytes); 357 break; 358 case I2C_SMBUS_I2C_BLOCK_DATA: 359 memcpy(&data->block[1], dma_buffer, desc->rxbytes); 360 data->block[0] = desc->rxbytes; 361 break; 362 } 363 return 0; 364 } 365 366 if (likely(desc->status & ISMT_DESC_NAK)) 367 return -ENXIO; 368 369 if (desc->status & ISMT_DESC_CRC) 370 return -EBADMSG; 371 372 if (desc->status & ISMT_DESC_COL) 373 return -EAGAIN; 374 375 if (desc->status & ISMT_DESC_LPR) 376 return -EPROTO; 377 378 if (desc->status & (ISMT_DESC_DLTO | ISMT_DESC_CLTO)) 379 return -ETIMEDOUT; 380 381 return -EIO; 382} 383 384/** 385 * ismt_access() - process an SMBus command 386 * @adap: the i2c host adapter 387 * @addr: address of the i2c/SMBus target 388 * @flags: command options 389 * @read_write: read from or write to device 390 * @command: the i2c/SMBus command to issue 391 * @size: SMBus transaction type 392 * @data: read/write data buffer 393 */ 394static int ismt_access(struct i2c_adapter *adap, u16 addr, 395 unsigned short flags, char read_write, u8 command, 396 int size, union i2c_smbus_data *data) 397{ 398 int ret; 399 unsigned long time_left; 400 dma_addr_t dma_addr = 0; /* address of the data buffer */ 401 u8 dma_size = 0; 402 enum dma_data_direction dma_direction = 0; 403 struct ismt_desc *desc; 404 struct ismt_priv *priv = i2c_get_adapdata(adap); 405 struct device *dev = &priv->pci_dev->dev; 406 u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); 407 408 desc = &priv->hw[priv->head]; 409 410 /* Initialize the DMA buffer */ 411 memset(priv->buffer, 0, sizeof(priv->buffer)); 412 413 /* Initialize the descriptor */ 414 memset(desc, 0, sizeof(struct ismt_desc)); 415 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); 416 417 /* Always clear the log entries */ 418 memset(priv->log, 0, ISMT_LOG_ENTRIES * sizeof(u32)); 419 420 /* Initialize common control bits */ 421 if (likely(pci_dev_msi_enabled(priv->pci_dev))) 422 desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR; 423 else 424 desc->control = ISMT_DESC_FAIR; 425 426 if ((flags & I2C_CLIENT_PEC) && (size != I2C_SMBUS_QUICK) 427 && (size != I2C_SMBUS_I2C_BLOCK_DATA)) 428 desc->control |= ISMT_DESC_PEC; 429 430 switch (size) { 431 case I2C_SMBUS_QUICK: 432 dev_dbg(dev, "I2C_SMBUS_QUICK\n"); 433 break; 434 435 case I2C_SMBUS_BYTE: 436 if (read_write == I2C_SMBUS_WRITE) { 437 /* 438 * Send Byte 439 * The command field contains the write data 440 */ 441 dev_dbg(dev, "I2C_SMBUS_BYTE: WRITE\n"); 442 desc->control |= ISMT_DESC_CWRL; 443 desc->wr_len_cmd = command; 444 } else { 445 /* Receive Byte */ 446 dev_dbg(dev, "I2C_SMBUS_BYTE: READ\n"); 447 dma_size = 1; 448 dma_direction = DMA_FROM_DEVICE; 449 desc->rd_len = 1; 450 } 451 break; 452 453 case I2C_SMBUS_BYTE_DATA: 454 if (read_write == I2C_SMBUS_WRITE) { 455 /* 456 * Write Byte 457 * Command plus 1 data byte 458 */ 459 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: WRITE\n"); 460 desc->wr_len_cmd = 2; 461 dma_size = 2; 462 dma_direction = DMA_TO_DEVICE; 463 dma_buffer[0] = command; 464 dma_buffer[1] = data->byte; 465 } else { 466 /* Read Byte */ 467 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: READ\n"); 468 desc->control |= ISMT_DESC_CWRL; 469 desc->wr_len_cmd = command; 470 desc->rd_len = 1; 471 dma_size = 1; 472 dma_direction = DMA_FROM_DEVICE; 473 } 474 break; 475 476 case I2C_SMBUS_WORD_DATA: 477 if (read_write == I2C_SMBUS_WRITE) { 478 /* Write Word */ 479 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: WRITE\n"); 480 desc->wr_len_cmd = 3; 481 dma_size = 3; 482 dma_direction = DMA_TO_DEVICE; 483 dma_buffer[0] = command; 484 dma_buffer[1] = data->word & 0xff; 485 dma_buffer[2] = data->word >> 8; 486 } else { 487 /* Read Word */ 488 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: READ\n"); 489 desc->wr_len_cmd = command; 490 desc->control |= ISMT_DESC_CWRL; 491 desc->rd_len = 2; 492 dma_size = 2; 493 dma_direction = DMA_FROM_DEVICE; 494 } 495 break; 496 497 case I2C_SMBUS_PROC_CALL: 498 dev_dbg(dev, "I2C_SMBUS_PROC_CALL\n"); 499 desc->wr_len_cmd = 3; 500 desc->rd_len = 2; 501 dma_size = 3; 502 dma_direction = DMA_BIDIRECTIONAL; 503 dma_buffer[0] = command; 504 dma_buffer[1] = data->word & 0xff; 505 dma_buffer[2] = data->word >> 8; 506 break; 507 508 case I2C_SMBUS_BLOCK_DATA: 509 if (read_write == I2C_SMBUS_WRITE) { 510 /* Block Write */ 511 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: WRITE\n"); 512 if (data->block[0] < 1 || data->block[0] > I2C_SMBUS_BLOCK_MAX) 513 return -EINVAL; 514 515 dma_size = data->block[0] + 1; 516 dma_direction = DMA_TO_DEVICE; 517 desc->wr_len_cmd = dma_size; 518 desc->control |= ISMT_DESC_BLK; 519 dma_buffer[0] = command; 520 memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); 521 } else { 522 /* Block Read */ 523 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n"); 524 dma_size = I2C_SMBUS_BLOCK_MAX; 525 dma_direction = DMA_FROM_DEVICE; 526 desc->rd_len = dma_size; 527 desc->wr_len_cmd = command; 528 desc->control |= (ISMT_DESC_BLK | ISMT_DESC_CWRL); 529 } 530 break; 531 532 case I2C_SMBUS_BLOCK_PROC_CALL: 533 dev_dbg(dev, "I2C_SMBUS_BLOCK_PROC_CALL\n"); 534 if (data->block[0] > I2C_SMBUS_BLOCK_MAX) 535 return -EINVAL; 536 537 dma_size = I2C_SMBUS_BLOCK_MAX; 538 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 1); 539 desc->wr_len_cmd = data->block[0] + 1; 540 desc->rd_len = dma_size; 541 desc->control |= ISMT_DESC_BLK; 542 dma_direction = DMA_BIDIRECTIONAL; 543 dma_buffer[0] = command; 544 memcpy(&dma_buffer[1], &data->block[1], data->block[0]); 545 break; 546 547 case I2C_SMBUS_I2C_BLOCK_DATA: 548 /* Make sure the length is valid */ 549 if (data->block[0] < 1) 550 data->block[0] = 1; 551 552 if (data->block[0] > I2C_SMBUS_BLOCK_MAX) 553 data->block[0] = I2C_SMBUS_BLOCK_MAX; 554 555 if (read_write == I2C_SMBUS_WRITE) { 556 /* i2c Block Write */ 557 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n"); 558 dma_size = data->block[0] + 1; 559 dma_direction = DMA_TO_DEVICE; 560 desc->wr_len_cmd = dma_size; 561 desc->control |= ISMT_DESC_I2C; 562 dma_buffer[0] = command; 563 memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); 564 } else { 565 /* i2c Block Read */ 566 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n"); 567 dma_size = data->block[0]; 568 dma_direction = DMA_FROM_DEVICE; 569 desc->rd_len = dma_size; 570 desc->wr_len_cmd = command; 571 desc->control |= (ISMT_DESC_I2C | ISMT_DESC_CWRL); 572 /* 573 * Per the "Table 15-15. I2C Commands", 574 * in the External Design Specification (EDS), 575 * (Document Number: 508084, Revision: 2.0), 576 * the _rw bit must be 0 577 */ 578 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 0); 579 } 580 break; 581 582 default: 583 dev_err(dev, "Unsupported transaction %d\n", 584 size); 585 return -EOPNOTSUPP; 586 } 587 588 /* map the data buffer */ 589 if (dma_size != 0) { 590 dev_dbg(dev, " dev=%p\n", dev); 591 dev_dbg(dev, " data=%p\n", data); 592 dev_dbg(dev, " dma_buffer=%p\n", dma_buffer); 593 dev_dbg(dev, " dma_size=%d\n", dma_size); 594 dev_dbg(dev, " dma_direction=%d\n", dma_direction); 595 596 dma_addr = dma_map_single(dev, 597 dma_buffer, 598 dma_size, 599 dma_direction); 600 601 if (dma_mapping_error(dev, dma_addr)) { 602 dev_err(dev, "Error in mapping dma buffer %p\n", 603 dma_buffer); 604 return -EIO; 605 } 606 607 dev_dbg(dev, " dma_addr = %pad\n", &dma_addr); 608 609 desc->dptr_low = lower_32_bits(dma_addr); 610 desc->dptr_high = upper_32_bits(dma_addr); 611 } 612 613 reinit_completion(&priv->cmp); 614 615 /* Add the descriptor */ 616 ismt_submit_desc(priv); 617 618 /* Now we wait for interrupt completion, 1s */ 619 time_left = wait_for_completion_timeout(&priv->cmp, HZ*1); 620 621 /* unmap the data buffer */ 622 if (dma_size != 0) 623 dma_unmap_single(dev, dma_addr, dma_size, dma_direction); 624 625 if (unlikely(!time_left)) { 626 dev_err(dev, "completion wait timed out\n"); 627 ret = -ETIMEDOUT; 628 goto out; 629 } 630 631 /* do any post processing of the descriptor here */ 632 ret = ismt_process_desc(desc, data, priv, size, read_write); 633 634out: 635 /* Update the ring pointer */ 636 priv->head++; 637 priv->head %= ISMT_DESC_ENTRIES; 638 639 return ret; 640} 641 642/** 643 * ismt_func() - report which i2c commands are supported by this adapter 644 * @adap: the i2c host adapter 645 */ 646static u32 ismt_func(struct i2c_adapter *adap) 647{ 648 return I2C_FUNC_SMBUS_QUICK | 649 I2C_FUNC_SMBUS_BYTE | 650 I2C_FUNC_SMBUS_BYTE_DATA | 651 I2C_FUNC_SMBUS_WORD_DATA | 652 I2C_FUNC_SMBUS_PROC_CALL | 653 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 654 I2C_FUNC_SMBUS_BLOCK_DATA | 655 I2C_FUNC_SMBUS_I2C_BLOCK | 656 I2C_FUNC_SMBUS_PEC; 657} 658 659static const struct i2c_algorithm smbus_algorithm = { 660 .smbus_xfer = ismt_access, 661 .functionality = ismt_func, 662}; 663 664/** 665 * ismt_handle_isr() - interrupt handler bottom half 666 * @priv: iSMT private data 667 */ 668static irqreturn_t ismt_handle_isr(struct ismt_priv *priv) 669{ 670 complete(&priv->cmp); 671 672 return IRQ_HANDLED; 673} 674 675 676/** 677 * ismt_do_interrupt() - IRQ interrupt handler 678 * @vec: interrupt vector 679 * @data: iSMT private data 680 */ 681static irqreturn_t ismt_do_interrupt(int vec, void *data) 682{ 683 u32 val; 684 struct ismt_priv *priv = data; 685 686 /* 687 * check to see it's our interrupt, return IRQ_NONE if not ours 688 * since we are sharing interrupt 689 */ 690 val = readl(priv->smba + ISMT_MSTR_MSTS); 691 692 if (!(val & (ISMT_MSTS_MIS | ISMT_MSTS_MEIS))) 693 return IRQ_NONE; 694 else 695 writel(val | ISMT_MSTS_MIS | ISMT_MSTS_MEIS, 696 priv->smba + ISMT_MSTR_MSTS); 697 698 return ismt_handle_isr(priv); 699} 700 701/** 702 * ismt_do_msi_interrupt() - MSI interrupt handler 703 * @vec: interrupt vector 704 * @data: iSMT private data 705 */ 706static irqreturn_t ismt_do_msi_interrupt(int vec, void *data) 707{ 708 return ismt_handle_isr(data); 709} 710 711/** 712 * ismt_hw_init() - initialize the iSMT hardware 713 * @priv: iSMT private data 714 */ 715static void ismt_hw_init(struct ismt_priv *priv) 716{ 717 u32 val; 718 struct device *dev = &priv->pci_dev->dev; 719 720 /* initialize the Master Descriptor Base Address (MDBA) */ 721 writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); 722 723 writeq(priv->log_dma, priv->smba + ISMT_GR_SMTICL); 724 725 /* initialize the Master Control Register (MCTRL) */ 726 writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL); 727 728 /* initialize the Master Status Register (MSTS) */ 729 writel(0, priv->smba + ISMT_MSTR_MSTS); 730 731 /* initialize the Master Descriptor Size (MDS) */ 732 val = readl(priv->smba + ISMT_MSTR_MDS); 733 writel((val & ~ISMT_MDS_MASK) | (ISMT_DESC_ENTRIES - 1), 734 priv->smba + ISMT_MSTR_MDS); 735 736 /* 737 * Set the SMBus speed (could use this for slow HW debuggers) 738 */ 739 740 val = readl(priv->smba + ISMT_SPGT); 741 742 switch (bus_speed) { 743 case 0: 744 break; 745 746 case 80: 747 dev_dbg(dev, "Setting SMBus clock to 80 kHz\n"); 748 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_80K), 749 priv->smba + ISMT_SPGT); 750 break; 751 752 case 100: 753 dev_dbg(dev, "Setting SMBus clock to 100 kHz\n"); 754 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_100K), 755 priv->smba + ISMT_SPGT); 756 break; 757 758 case 400: 759 dev_dbg(dev, "Setting SMBus clock to 400 kHz\n"); 760 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_400K), 761 priv->smba + ISMT_SPGT); 762 break; 763 764 case 1000: 765 dev_dbg(dev, "Setting SMBus clock to 1000 kHz\n"); 766 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_1M), 767 priv->smba + ISMT_SPGT); 768 break; 769 770 default: 771 dev_warn(dev, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n"); 772 break; 773 } 774 775 val = readl(priv->smba + ISMT_SPGT); 776 777 switch (val & ISMT_SPGT_SPD_MASK) { 778 case ISMT_SPGT_SPD_80K: 779 bus_speed = 80; 780 break; 781 case ISMT_SPGT_SPD_100K: 782 bus_speed = 100; 783 break; 784 case ISMT_SPGT_SPD_400K: 785 bus_speed = 400; 786 break; 787 case ISMT_SPGT_SPD_1M: 788 bus_speed = 1000; 789 break; 790 } 791 dev_dbg(dev, "SMBus clock is running at %d kHz\n", bus_speed); 792} 793 794/** 795 * ismt_dev_init() - initialize the iSMT data structures 796 * @priv: iSMT private data 797 */ 798static int ismt_dev_init(struct ismt_priv *priv) 799{ 800 /* allocate memory for the descriptor */ 801 priv->hw = dmam_alloc_coherent(&priv->pci_dev->dev, 802 (ISMT_DESC_ENTRIES 803 * sizeof(struct ismt_desc)), 804 &priv->io_rng_dma, 805 GFP_KERNEL); 806 if (!priv->hw) 807 return -ENOMEM; 808 809 priv->head = 0; 810 init_completion(&priv->cmp); 811 812 priv->log = dmam_alloc_coherent(&priv->pci_dev->dev, 813 ISMT_LOG_ENTRIES * sizeof(u32), 814 &priv->log_dma, GFP_KERNEL); 815 if (!priv->log) 816 return -ENOMEM; 817 818 return 0; 819} 820 821/** 822 * ismt_int_init() - initialize interrupts 823 * @priv: iSMT private data 824 */ 825static int ismt_int_init(struct ismt_priv *priv) 826{ 827 int err; 828 829 /* Try using MSI interrupts */ 830 err = pci_enable_msi(priv->pci_dev); 831 if (err) 832 goto intx; 833 834 err = devm_request_irq(&priv->pci_dev->dev, 835 priv->pci_dev->irq, 836 ismt_do_msi_interrupt, 837 0, 838 "ismt-msi", 839 priv); 840 if (err) { 841 pci_disable_msi(priv->pci_dev); 842 goto intx; 843 } 844 845 return 0; 846 847 /* Try using legacy interrupts */ 848intx: 849 dev_warn(&priv->pci_dev->dev, 850 "Unable to use MSI interrupts, falling back to legacy\n"); 851 852 err = devm_request_irq(&priv->pci_dev->dev, 853 priv->pci_dev->irq, 854 ismt_do_interrupt, 855 IRQF_SHARED, 856 "ismt-intx", 857 priv); 858 if (err) { 859 dev_err(&priv->pci_dev->dev, "no usable interrupts\n"); 860 return err; 861 } 862 863 return 0; 864} 865 866static struct pci_driver ismt_driver; 867 868/** 869 * ismt_probe() - probe for iSMT devices 870 * @pdev: PCI-Express device 871 * @id: PCI-Express device ID 872 */ 873static int 874ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id) 875{ 876 int err; 877 struct ismt_priv *priv; 878 unsigned long start, len; 879 880 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 881 if (!priv) 882 return -ENOMEM; 883 884 pci_set_drvdata(pdev, priv); 885 886 i2c_set_adapdata(&priv->adapter, priv); 887 priv->adapter.owner = THIS_MODULE; 888 priv->adapter.class = I2C_CLASS_HWMON; 889 priv->adapter.algo = &smbus_algorithm; 890 priv->adapter.dev.parent = &pdev->dev; 891 ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev)); 892 priv->adapter.retries = ISMT_MAX_RETRIES; 893 894 priv->pci_dev = pdev; 895 896 err = pcim_enable_device(pdev); 897 if (err) { 898 dev_err(&pdev->dev, "Failed to enable SMBus PCI device (%d)\n", 899 err); 900 return err; 901 } 902 903 /* enable bus mastering */ 904 pci_set_master(pdev); 905 906 /* Determine the address of the SMBus area */ 907 start = pci_resource_start(pdev, SMBBAR); 908 len = pci_resource_len(pdev, SMBBAR); 909 if (!start || !len) { 910 dev_err(&pdev->dev, 911 "SMBus base address uninitialized, upgrade BIOS\n"); 912 return -ENODEV; 913 } 914 915 snprintf(priv->adapter.name, sizeof(priv->adapter.name), 916 "SMBus iSMT adapter at %lx", start); 917 918 dev_dbg(&priv->pci_dev->dev, " start=0x%lX\n", start); 919 dev_dbg(&priv->pci_dev->dev, " len=0x%lX\n", len); 920 921 err = acpi_check_resource_conflict(&pdev->resource[SMBBAR]); 922 if (err) { 923 dev_err(&pdev->dev, "ACPI resource conflict!\n"); 924 return err; 925 } 926 927 err = pci_request_region(pdev, SMBBAR, ismt_driver.name); 928 if (err) { 929 dev_err(&pdev->dev, 930 "Failed to request SMBus region 0x%lx-0x%lx\n", 931 start, start + len); 932 return err; 933 } 934 935 priv->smba = pcim_iomap(pdev, SMBBAR, len); 936 if (!priv->smba) { 937 dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n"); 938 return -ENODEV; 939 } 940 941 err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); 942 if (err) { 943 dev_err(&pdev->dev, "dma_set_mask fail\n"); 944 return -ENODEV; 945 } 946 947 err = ismt_dev_init(priv); 948 if (err) 949 return err; 950 951 ismt_hw_init(priv); 952 953 err = ismt_int_init(priv); 954 if (err) 955 return err; 956 957 err = i2c_add_adapter(&priv->adapter); 958 if (err) 959 return -ENODEV; 960 return 0; 961} 962 963/** 964 * ismt_remove() - release driver resources 965 * @pdev: PCI-Express device 966 */ 967static void ismt_remove(struct pci_dev *pdev) 968{ 969 struct ismt_priv *priv = pci_get_drvdata(pdev); 970 971 i2c_del_adapter(&priv->adapter); 972} 973 974static struct pci_driver ismt_driver = { 975 .name = "ismt_smbus", 976 .id_table = ismt_ids, 977 .probe = ismt_probe, 978 .remove = ismt_remove, 979}; 980 981module_pci_driver(ismt_driver); 982 983MODULE_LICENSE("Dual BSD/GPL"); 984MODULE_AUTHOR("Bill E. Brown <bill.e.brown@intel.com>"); 985MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver"); 986