linux/drivers/platform/x86/intel_scu_ipc.c
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   1/*
   2 * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism
   3 *
   4 * (C) Copyright 2008-2010 Intel Corporation
   5 * Author: Sreedhara DS (sreedhara.ds@intel.com)
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License
   9 * as published by the Free Software Foundation; version 2
  10 * of the License.
  11 *
  12 * SCU running in ARC processor communicates with other entity running in IA
  13 * core through IPC mechanism which in turn messaging between IA core ad SCU.
  14 * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and
  15 * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with
  16 * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC)
  17 * along with other APIs.
  18 */
  19#include <linux/delay.h>
  20#include <linux/errno.h>
  21#include <linux/init.h>
  22#include <linux/sysdev.h>
  23#include <linux/pm.h>
  24#include <linux/pci.h>
  25#include <linux/interrupt.h>
  26#include <linux/sfi.h>
  27#include <linux/module.h>
  28#include <asm/mrst.h>
  29#include <asm/intel_scu_ipc.h>
  30
  31/* IPC defines the following message types */
  32#define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
  33#define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
  34#define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
  35#define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
  36#define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
  37
  38/* Command id associated with message IPCMSG_PCNTRL */
  39#define IPC_CMD_PCNTRL_W      0 /* Register write */
  40#define IPC_CMD_PCNTRL_R      1 /* Register read */
  41#define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
  42
  43/*
  44 * IPC register summary
  45 *
  46 * IPC register blocks are memory mapped at fixed address of 0xFF11C000
  47 * To read or write information to the SCU, driver writes to IPC-1 memory
  48 * mapped registers (base address 0xFF11C000). The following is the IPC
  49 * mechanism
  50 *
  51 * 1. IA core cDMI interface claims this transaction and converts it to a
  52 *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
  53 *
  54 * 2. South Complex cDMI block receives this message and writes it to
  55 *    the IPC-1 register block, causing an interrupt to the SCU
  56 *
  57 * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
  58 *    message handler is called within firmware.
  59 */
  60
  61#define IPC_BASE_ADDR     0xFF11C000    /* IPC1 base register address */
  62#define IPC_MAX_ADDR      0x100         /* Maximum IPC regisers */
  63#define IPC_WWBUF_SIZE    20            /* IPC Write buffer Size */
  64#define IPC_RWBUF_SIZE    20            /* IPC Read buffer Size */
  65#define IPC_I2C_BASE      0xFF12B000    /* I2C control register base address */
  66#define IPC_I2C_MAX_ADDR  0x10          /* Maximum I2C regisers */
  67
  68static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id);
  69static void ipc_remove(struct pci_dev *pdev);
  70
  71struct intel_scu_ipc_dev {
  72        struct pci_dev *pdev;
  73        void __iomem *ipc_base;
  74        void __iomem *i2c_base;
  75};
  76
  77static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
  78
  79static int platform;            /* Platform type */
  80
  81/*
  82 * IPC Read Buffer (Read Only):
  83 * 16 byte buffer for receiving data from SCU, if IPC command
  84 * processing results in response data
  85 */
  86#define IPC_READ_BUFFER         0x90
  87
  88#define IPC_I2C_CNTRL_ADDR      0
  89#define I2C_DATA_ADDR           0x04
  90
  91static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
  92
  93/*
  94 * Command Register (Write Only):
  95 * A write to this register results in an interrupt to the SCU core processor
  96 * Format:
  97 * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
  98 */
  99static inline void ipc_command(u32 cmd) /* Send ipc command */
 100{
 101        writel(cmd, ipcdev.ipc_base);
 102}
 103
 104/*
 105 * IPC Write Buffer (Write Only):
 106 * 16-byte buffer for sending data associated with IPC command to
 107 * SCU. Size of the data is specified in the IPC_COMMAND_REG register
 108 */
 109static inline void ipc_data_writel(u32 data, u32 offset) /* Write ipc data */
 110{
 111        writel(data, ipcdev.ipc_base + 0x80 + offset);
 112}
 113
 114/*
 115 * Status Register (Read Only):
 116 * Driver will read this register to get the ready/busy status of the IPC
 117 * block and error status of the IPC command that was just processed by SCU
 118 * Format:
 119 * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
 120 */
 121
 122static inline u8 ipc_read_status(void)
 123{
 124        return __raw_readl(ipcdev.ipc_base + 0x04);
 125}
 126
 127static inline u8 ipc_data_readb(u32 offset) /* Read ipc byte data */
 128{
 129        return readb(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
 130}
 131
 132static inline u32 ipc_data_readl(u32 offset) /* Read ipc u32 data */
 133{
 134        return readl(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
 135}
 136
 137static inline int busy_loop(void) /* Wait till scu status is busy */
 138{
 139        u32 status = 0;
 140        u32 loop_count = 0;
 141
 142        status = ipc_read_status();
 143        while (status & 1) {
 144                udelay(1); /* scu processing time is in few u secods */
 145                status = ipc_read_status();
 146                loop_count++;
 147                /* break if scu doesn't reset busy bit after huge retry */
 148                if (loop_count > 100000) {
 149                        dev_err(&ipcdev.pdev->dev, "IPC timed out");
 150                        return -ETIMEDOUT;
 151                }
 152        }
 153        if ((status >> 1) & 1)
 154                return -EIO;
 155
 156        return 0;
 157}
 158
 159/* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
 160static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
 161{
 162        int i, nc, bytes, d;
 163        u32 offset = 0;
 164        int err;
 165        u8 cbuf[IPC_WWBUF_SIZE] = { };
 166        u32 *wbuf = (u32 *)&cbuf;
 167
 168        mutex_lock(&ipclock);
 169
 170        memset(cbuf, 0, sizeof(cbuf));
 171
 172        if (ipcdev.pdev == NULL) {
 173                mutex_unlock(&ipclock);
 174                return -ENODEV;
 175        }
 176
 177        if (platform != MRST_CPU_CHIP_PENWELL) {
 178                bytes = 0;
 179                d = 0;
 180                for (i = 0; i < count; i++) {
 181                        cbuf[bytes++] = addr[i];
 182                        cbuf[bytes++] = addr[i] >> 8;
 183                        if (id != IPC_CMD_PCNTRL_R)
 184                                cbuf[bytes++] = data[d++];
 185                        if (id == IPC_CMD_PCNTRL_M)
 186                                cbuf[bytes++] = data[d++];
 187                }
 188                for (i = 0; i < bytes; i += 4)
 189                        ipc_data_writel(wbuf[i/4], i);
 190                ipc_command(bytes << 16 |  id << 12 | 0 << 8 | op);
 191        } else {
 192                for (nc = 0; nc < count; nc++, offset += 2) {
 193                        cbuf[offset] = addr[nc];
 194                        cbuf[offset + 1] = addr[nc] >> 8;
 195                }
 196
 197                if (id == IPC_CMD_PCNTRL_R) {
 198                        for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
 199                                ipc_data_writel(wbuf[nc], offset);
 200                        ipc_command((count*2) << 16 |  id << 12 | 0 << 8 | op);
 201                } else if (id == IPC_CMD_PCNTRL_W) {
 202                        for (nc = 0; nc < count; nc++, offset += 1)
 203                                cbuf[offset] = data[nc];
 204                        for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
 205                                ipc_data_writel(wbuf[nc], offset);
 206                        ipc_command((count*3) << 16 |  id << 12 | 0 << 8 | op);
 207                } else if (id == IPC_CMD_PCNTRL_M) {
 208                        cbuf[offset] = data[0];
 209                        cbuf[offset + 1] = data[1];
 210                        ipc_data_writel(wbuf[0], 0); /* Write wbuff */
 211                        ipc_command(4 << 16 |  id << 12 | 0 << 8 | op);
 212                }
 213        }
 214
 215        err = busy_loop();
 216        if (id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
 217                /* Workaround: values are read as 0 without memcpy_fromio */
 218                memcpy_fromio(cbuf, ipcdev.ipc_base + 0x90, 16);
 219                if (platform != MRST_CPU_CHIP_PENWELL) {
 220                        for (nc = 0, offset = 2; nc < count; nc++, offset += 3)
 221                                data[nc] = ipc_data_readb(offset);
 222                } else {
 223                        for (nc = 0; nc < count; nc++)
 224                                data[nc] = ipc_data_readb(nc);
 225                }
 226        }
 227        mutex_unlock(&ipclock);
 228        return err;
 229}
 230
 231/**
 232 *      intel_scu_ipc_ioread8           -       read a word via the SCU
 233 *      @addr: register on SCU
 234 *      @data: return pointer for read byte
 235 *
 236 *      Read a single register. Returns 0 on success or an error code. All
 237 *      locking between SCU accesses is handled for the caller.
 238 *
 239 *      This function may sleep.
 240 */
 241int intel_scu_ipc_ioread8(u16 addr, u8 *data)
 242{
 243        return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
 244}
 245EXPORT_SYMBOL(intel_scu_ipc_ioread8);
 246
 247/**
 248 *      intel_scu_ipc_ioread16          -       read a word via the SCU
 249 *      @addr: register on SCU
 250 *      @data: return pointer for read word
 251 *
 252 *      Read a register pair. Returns 0 on success or an error code. All
 253 *      locking between SCU accesses is handled for the caller.
 254 *
 255 *      This function may sleep.
 256 */
 257int intel_scu_ipc_ioread16(u16 addr, u16 *data)
 258{
 259        u16 x[2] = {addr, addr + 1 };
 260        return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
 261}
 262EXPORT_SYMBOL(intel_scu_ipc_ioread16);
 263
 264/**
 265 *      intel_scu_ipc_ioread32          -       read a dword via the SCU
 266 *      @addr: register on SCU
 267 *      @data: return pointer for read dword
 268 *
 269 *      Read four registers. Returns 0 on success or an error code. All
 270 *      locking between SCU accesses is handled for the caller.
 271 *
 272 *      This function may sleep.
 273 */
 274int intel_scu_ipc_ioread32(u16 addr, u32 *data)
 275{
 276        u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
 277        return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
 278}
 279EXPORT_SYMBOL(intel_scu_ipc_ioread32);
 280
 281/**
 282 *      intel_scu_ipc_iowrite8          -       write a byte via the SCU
 283 *      @addr: register on SCU
 284 *      @data: byte to write
 285 *
 286 *      Write a single register. Returns 0 on success or an error code. All
 287 *      locking between SCU accesses is handled for the caller.
 288 *
 289 *      This function may sleep.
 290 */
 291int intel_scu_ipc_iowrite8(u16 addr, u8 data)
 292{
 293        return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
 294}
 295EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
 296
 297/**
 298 *      intel_scu_ipc_iowrite16         -       write a word via the SCU
 299 *      @addr: register on SCU
 300 *      @data: word to write
 301 *
 302 *      Write two registers. Returns 0 on success or an error code. All
 303 *      locking between SCU accesses is handled for the caller.
 304 *
 305 *      This function may sleep.
 306 */
 307int intel_scu_ipc_iowrite16(u16 addr, u16 data)
 308{
 309        u16 x[2] = {addr, addr + 1 };
 310        return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
 311}
 312EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
 313
 314/**
 315 *      intel_scu_ipc_iowrite32         -       write a dword via the SCU
 316 *      @addr: register on SCU
 317 *      @data: dword to write
 318 *
 319 *      Write four registers. Returns 0 on success or an error code. All
 320 *      locking between SCU accesses is handled for the caller.
 321 *
 322 *      This function may sleep.
 323 */
 324int intel_scu_ipc_iowrite32(u16 addr, u32 data)
 325{
 326        u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
 327        return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
 328}
 329EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
 330
 331/**
 332 *      intel_scu_ipc_readvv            -       read a set of registers
 333 *      @addr: register list
 334 *      @data: bytes to return
 335 *      @len: length of array
 336 *
 337 *      Read registers. Returns 0 on success or an error code. All
 338 *      locking between SCU accesses is handled for the caller.
 339 *
 340 *      The largest array length permitted by the hardware is 5 items.
 341 *
 342 *      This function may sleep.
 343 */
 344int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
 345{
 346        return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
 347}
 348EXPORT_SYMBOL(intel_scu_ipc_readv);
 349
 350/**
 351 *      intel_scu_ipc_writev            -       write a set of registers
 352 *      @addr: register list
 353 *      @data: bytes to write
 354 *      @len: length of array
 355 *
 356 *      Write registers. Returns 0 on success or an error code. All
 357 *      locking between SCU accesses is handled for the caller.
 358 *
 359 *      The largest array length permitted by the hardware is 5 items.
 360 *
 361 *      This function may sleep.
 362 *
 363 */
 364int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
 365{
 366        return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
 367}
 368EXPORT_SYMBOL(intel_scu_ipc_writev);
 369
 370
 371/**
 372 *      intel_scu_ipc_update_register   -       r/m/w a register
 373 *      @addr: register address
 374 *      @bits: bits to update
 375 *      @mask: mask of bits to update
 376 *
 377 *      Read-modify-write power control unit register. The first data argument
 378 *      must be register value and second is mask value
 379 *      mask is a bitmap that indicates which bits to update.
 380 *      0 = masked. Don't modify this bit, 1 = modify this bit.
 381 *      returns 0 on success or an error code.
 382 *
 383 *      This function may sleep. Locking between SCU accesses is handled
 384 *      for the caller.
 385 */
 386int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
 387{
 388        u8 data[2] = { bits, mask };
 389        return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
 390}
 391EXPORT_SYMBOL(intel_scu_ipc_update_register);
 392
 393/**
 394 *      intel_scu_ipc_simple_command    -       send a simple command
 395 *      @cmd: command
 396 *      @sub: sub type
 397 *
 398 *      Issue a simple command to the SCU. Do not use this interface if
 399 *      you must then access data as any data values may be overwritten
 400 *      by another SCU access by the time this function returns.
 401 *
 402 *      This function may sleep. Locking for SCU accesses is handled for
 403 *      the caller.
 404 */
 405int intel_scu_ipc_simple_command(int cmd, int sub)
 406{
 407        int err;
 408
 409        mutex_lock(&ipclock);
 410        if (ipcdev.pdev == NULL) {
 411                mutex_unlock(&ipclock);
 412                return -ENODEV;
 413        }
 414        ipc_command(sub << 12 | cmd);
 415        err = busy_loop();
 416        mutex_unlock(&ipclock);
 417        return err;
 418}
 419EXPORT_SYMBOL(intel_scu_ipc_simple_command);
 420
 421/**
 422 *      intel_scu_ipc_command   -       command with data
 423 *      @cmd: command
 424 *      @sub: sub type
 425 *      @in: input data
 426 *      @inlen: input length in dwords
 427 *      @out: output data
 428 *      @outlein: output length in dwords
 429 *
 430 *      Issue a command to the SCU which involves data transfers. Do the
 431 *      data copies under the lock but leave it for the caller to interpret
 432 */
 433
 434int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
 435                                                        u32 *out, int outlen)
 436{
 437        int i, err;
 438
 439        mutex_lock(&ipclock);
 440        if (ipcdev.pdev == NULL) {
 441                mutex_unlock(&ipclock);
 442                return -ENODEV;
 443        }
 444
 445        for (i = 0; i < inlen; i++)
 446                ipc_data_writel(*in++, 4 * i);
 447
 448        ipc_command((inlen << 16) | (sub << 12) | cmd);
 449        err = busy_loop();
 450
 451        for (i = 0; i < outlen; i++)
 452                *out++ = ipc_data_readl(4 * i);
 453
 454        mutex_unlock(&ipclock);
 455        return err;
 456}
 457EXPORT_SYMBOL(intel_scu_ipc_command);
 458
 459/*I2C commands */
 460#define IPC_I2C_WRITE 1 /* I2C Write command */
 461#define IPC_I2C_READ  2 /* I2C Read command */
 462
 463/**
 464 *      intel_scu_ipc_i2c_cntrl         -       I2C read/write operations
 465 *      @addr: I2C address + command bits
 466 *      @data: data to read/write
 467 *
 468 *      Perform an an I2C read/write operation via the SCU. All locking is
 469 *      handled for the caller. This function may sleep.
 470 *
 471 *      Returns an error code or 0 on success.
 472 *
 473 *      This has to be in the IPC driver for the locking.
 474 */
 475int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
 476{
 477        u32 cmd = 0;
 478
 479        mutex_lock(&ipclock);
 480        if (ipcdev.pdev == NULL) {
 481                mutex_unlock(&ipclock);
 482                return -ENODEV;
 483        }
 484        cmd = (addr >> 24) & 0xFF;
 485        if (cmd == IPC_I2C_READ) {
 486                writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
 487                /* Write not getting updated without delay */
 488                mdelay(1);
 489                *data = readl(ipcdev.i2c_base + I2C_DATA_ADDR);
 490        } else if (cmd == IPC_I2C_WRITE) {
 491                writel(*data, ipcdev.i2c_base + I2C_DATA_ADDR);
 492                mdelay(1);
 493                writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
 494        } else {
 495                dev_err(&ipcdev.pdev->dev,
 496                        "intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
 497
 498                mutex_unlock(&ipclock);
 499                return -EIO;
 500        }
 501        mutex_unlock(&ipclock);
 502        return 0;
 503}
 504EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
 505
 506#define IPC_FW_LOAD_ADDR 0xFFFC0000 /* Storage location for FW image */
 507#define IPC_FW_UPDATE_MBOX_ADDR 0xFFFFDFF4 /* Mailbox between ipc and scu */
 508#define IPC_MAX_FW_SIZE 262144 /* 256K storage size for loading the FW image */
 509#define IPC_FW_MIP_HEADER_SIZE 2048 /* Firmware MIP header size */
 510/* IPC inform SCU to get ready for update process */
 511#define IPC_CMD_FW_UPDATE_READY  0x10FE
 512/* IPC inform SCU to go for update process */
 513#define IPC_CMD_FW_UPDATE_GO     0x20FE
 514/* Status code for fw update */
 515#define IPC_FW_UPDATE_SUCCESS   0x444f4e45 /* Status code 'DONE' */
 516#define IPC_FW_UPDATE_BADN      0x4241444E /* Status code 'BADN' */
 517#define IPC_FW_TXHIGH           0x54784849 /* Status code 'IPC_FW_TXHIGH' */
 518#define IPC_FW_TXLOW            0x54784c4f /* Status code 'IPC_FW_TXLOW' */
 519
 520struct fw_update_mailbox {
 521        u32    status;
 522        u32    scu_flag;
 523        u32    driver_flag;
 524};
 525
 526
 527/**
 528 *      intel_scu_ipc_fw_update -        Firmware update utility
 529 *      @buffer: firmware buffer
 530 *      @length: size of firmware buffer
 531 *
 532 *      This function provides an interface to load the firmware into
 533 *      the SCU. Returns 0 on success or -1 on failure
 534 */
 535int intel_scu_ipc_fw_update(u8 *buffer, u32 length)
 536{
 537        void __iomem *fw_update_base;
 538        struct fw_update_mailbox __iomem *mailbox = NULL;
 539        int retry_cnt = 0;
 540        u32 status;
 541
 542        mutex_lock(&ipclock);
 543        fw_update_base = ioremap_nocache(IPC_FW_LOAD_ADDR, (128*1024));
 544        if (fw_update_base == NULL) {
 545                mutex_unlock(&ipclock);
 546                return -ENOMEM;
 547        }
 548        mailbox = ioremap_nocache(IPC_FW_UPDATE_MBOX_ADDR,
 549                                        sizeof(struct fw_update_mailbox));
 550        if (mailbox == NULL) {
 551                iounmap(fw_update_base);
 552                mutex_unlock(&ipclock);
 553                return -ENOMEM;
 554        }
 555
 556        ipc_command(IPC_CMD_FW_UPDATE_READY);
 557
 558        /* Intitialize mailbox */
 559        writel(0, &mailbox->status);
 560        writel(0, &mailbox->scu_flag);
 561        writel(0, &mailbox->driver_flag);
 562
 563        /* Driver copies the 2KB MIP header to SRAM at 0xFFFC0000*/
 564        memcpy_toio(fw_update_base, buffer, 0x800);
 565
 566        /* Driver sends "FW Update" IPC command (CMD_ID 0xFE; MSG_ID 0x02).
 567        * Upon receiving this command, SCU will write the 2K MIP header
 568        * from 0xFFFC0000 into NAND.
 569        * SCU will write a status code into the Mailbox, and then set scu_flag.
 570        */
 571
 572        ipc_command(IPC_CMD_FW_UPDATE_GO);
 573
 574        /*Driver stalls until scu_flag is set */
 575        while (readl(&mailbox->scu_flag) != 1) {
 576                rmb();
 577                mdelay(1);
 578        }
 579
 580        /* Driver checks Mailbox status.
 581         * If the status is 'BADN', then abort (bad NAND).
 582         * If the status is 'IPC_FW_TXLOW', then continue.
 583         */
 584        while (readl(&mailbox->status) != IPC_FW_TXLOW) {
 585                rmb();
 586                mdelay(10);
 587        }
 588        mdelay(10);
 589
 590update_retry:
 591        if (retry_cnt > 5)
 592                goto update_end;
 593
 594        if (readl(&mailbox->status) != IPC_FW_TXLOW)
 595                goto update_end;
 596        buffer = buffer + 0x800;
 597        memcpy_toio(fw_update_base, buffer, 0x20000);
 598        writel(1, &mailbox->driver_flag);
 599        while (readl(&mailbox->scu_flag) == 1) {
 600                rmb();
 601                mdelay(1);
 602        }
 603
 604        /* check for 'BADN' */
 605        if (readl(&mailbox->status) == IPC_FW_UPDATE_BADN)
 606                goto update_end;
 607
 608        while (readl(&mailbox->status) != IPC_FW_TXHIGH) {
 609                rmb();
 610                mdelay(10);
 611        }
 612        mdelay(10);
 613
 614        if (readl(&mailbox->status) != IPC_FW_TXHIGH)
 615                goto update_end;
 616
 617        buffer = buffer + 0x20000;
 618        memcpy_toio(fw_update_base, buffer, 0x20000);
 619        writel(0, &mailbox->driver_flag);
 620
 621        while (mailbox->scu_flag == 0) {
 622                rmb();
 623                mdelay(1);
 624        }
 625
 626        /* check for 'BADN' */
 627        if (readl(&mailbox->status) == IPC_FW_UPDATE_BADN)
 628                goto update_end;
 629
 630        if (readl(&mailbox->status) == IPC_FW_TXLOW) {
 631                ++retry_cnt;
 632                goto update_retry;
 633        }
 634
 635update_end:
 636        status = readl(&mailbox->status);
 637
 638        iounmap(fw_update_base);
 639        iounmap(mailbox);
 640        mutex_unlock(&ipclock);
 641
 642        if (status == IPC_FW_UPDATE_SUCCESS)
 643                return 0;
 644        return -EIO;
 645}
 646EXPORT_SYMBOL(intel_scu_ipc_fw_update);
 647
 648/*
 649 * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
 650 * When ioc bit is set to 1, caller api must wait for interrupt handler called
 651 * which in turn unlocks the caller api. Currently this is not used
 652 *
 653 * This is edge triggered so we need take no action to clear anything
 654 */
 655static irqreturn_t ioc(int irq, void *dev_id)
 656{
 657        return IRQ_HANDLED;
 658}
 659
 660/**
 661 *      ipc_probe       -       probe an Intel SCU IPC
 662 *      @dev: the PCI device matching
 663 *      @id: entry in the match table
 664 *
 665 *      Enable and install an intel SCU IPC. This appears in the PCI space
 666 *      but uses some hard coded addresses as well.
 667 */
 668static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id)
 669{
 670        int err;
 671        resource_size_t pci_resource;
 672
 673        if (ipcdev.pdev)                /* We support only one SCU */
 674                return -EBUSY;
 675
 676        ipcdev.pdev = pci_dev_get(dev);
 677
 678        err = pci_enable_device(dev);
 679        if (err)
 680                return err;
 681
 682        err = pci_request_regions(dev, "intel_scu_ipc");
 683        if (err)
 684                return err;
 685
 686        pci_resource = pci_resource_start(dev, 0);
 687        if (!pci_resource)
 688                return -ENOMEM;
 689
 690        if (request_irq(dev->irq, ioc, 0, "intel_scu_ipc", &ipcdev))
 691                return -EBUSY;
 692
 693        ipcdev.ipc_base = ioremap_nocache(IPC_BASE_ADDR, IPC_MAX_ADDR);
 694        if (!ipcdev.ipc_base)
 695                return -ENOMEM;
 696
 697        ipcdev.i2c_base = ioremap_nocache(IPC_I2C_BASE, IPC_I2C_MAX_ADDR);
 698        if (!ipcdev.i2c_base) {
 699                iounmap(ipcdev.ipc_base);
 700                return -ENOMEM;
 701        }
 702
 703        intel_scu_devices_create();
 704
 705        return 0;
 706}
 707
 708/**
 709 *      ipc_remove      -       remove a bound IPC device
 710 *      @pdev: PCI device
 711 *
 712 *      In practice the SCU is not removable but this function is also
 713 *      called for each device on a module unload or cleanup which is the
 714 *      path that will get used.
 715 *
 716 *      Free up the mappings and release the PCI resources
 717 */
 718static void ipc_remove(struct pci_dev *pdev)
 719{
 720        free_irq(pdev->irq, &ipcdev);
 721        pci_release_regions(pdev);
 722        pci_dev_put(ipcdev.pdev);
 723        iounmap(ipcdev.ipc_base);
 724        iounmap(ipcdev.i2c_base);
 725        ipcdev.pdev = NULL;
 726        intel_scu_devices_destroy();
 727}
 728
 729static DEFINE_PCI_DEVICE_TABLE(pci_ids) = {
 730        {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080e)},
 731        {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x082a)},
 732        { 0,}
 733};
 734MODULE_DEVICE_TABLE(pci, pci_ids);
 735
 736static struct pci_driver ipc_driver = {
 737        .name = "intel_scu_ipc",
 738        .id_table = pci_ids,
 739        .probe = ipc_probe,
 740        .remove = ipc_remove,
 741};
 742
 743
 744static int __init intel_scu_ipc_init(void)
 745{
 746        platform = mrst_identify_cpu();
 747        if (platform == 0)
 748                return -ENODEV;
 749        return  pci_register_driver(&ipc_driver);
 750}
 751
 752static void __exit intel_scu_ipc_exit(void)
 753{
 754        pci_unregister_driver(&ipc_driver);
 755}
 756
 757MODULE_AUTHOR("Sreedhara DS <sreedhara.ds@intel.com>");
 758MODULE_DESCRIPTION("Intel SCU IPC driver");
 759MODULE_LICENSE("GPL");
 760
 761module_init(intel_scu_ipc_init);
 762module_exit(intel_scu_ipc_exit);
 763
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