drivers/net/wireless/iwlwifi/iwl-io.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved.
   4  *
   5  * Portions of this file are derived from the ipw3945 project.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of version 2 of the GNU General Public License as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  19  *
  20  * The full GNU General Public License is included in this distribution in the
  21  * file called LICENSE.
  22  *
  23  * Contact Information:
  24  *  Intel Linux Wireless <ilw@linux.intel.com>
  25  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  26  *
  27  *****************************************************************************/
  28 #include <linux/delay.h>
  29 #include <linux/device.h>
  30 #include <linux/export.h>
  31
  32 #include "iwl-io.h"
  33 #include "iwl-csr.h"
  34 #include "iwl-debug.h"
  35
  36 #define IWL_POLL_INTERVAL 10    /* microseconds */
  37
  38 static inline void __iwl_set_bit(struct iwl_trans *trans, u32 reg, u32 mask)
  39 {
  40         iwl_write32(trans, reg, iwl_read32(trans, reg) | mask);
  41 }
  42
  43 static inline void __iwl_clear_bit(struct iwl_trans *trans, u32 reg, u32 mask)
  44 {
  45         iwl_write32(trans, reg, iwl_read32(trans, reg) & ~mask);
  46 }
  47
  48 void iwl_set_bit(struct iwl_trans *trans, u32 reg, u32 mask)
  49 {
  50         unsigned long flags;
  51
  52         spin_lock_irqsave(&trans->reg_lock, flags);
  53         __iwl_set_bit(trans, reg, mask);
  54         spin_unlock_irqrestore(&trans->reg_lock, flags);
  55 }
  56 EXPORT_SYMBOL_GPL(iwl_set_bit);
  57
  58 void iwl_clear_bit(struct iwl_trans *trans, u32 reg, u32 mask)
  59 {
  60         unsigned long flags;
  61
  62         spin_lock_irqsave(&trans->reg_lock, flags);
  63         __iwl_clear_bit(trans, reg, mask);
  64         spin_unlock_irqrestore(&trans->reg_lock, flags);
  65 }
  66 EXPORT_SYMBOL_GPL(iwl_clear_bit);
  67
  68 void iwl_set_bits_mask(struct iwl_trans *trans, u32 reg, u32 mask, u32 value)
  69 {
  70         unsigned long flags;
  71         u32 v;
  72
  73 #ifdef CONFIG_IWLWIFI_DEBUG
  74         WARN_ON_ONCE(value & ~mask);
  75 #endif
  76
  77         spin_lock_irqsave(&trans->reg_lock, flags);
  78         v = iwl_read32(trans, reg);
  79         v &= ~mask;
  80         v |= value;
  81         iwl_write32(trans, reg, v);
  82         spin_unlock_irqrestore(&trans->reg_lock, flags);
  83 }
  84 EXPORT_SYMBOL_GPL(iwl_set_bits_mask);
  85
  86 int iwl_poll_bit(struct iwl_trans *trans, u32 addr,
  87                  u32 bits, u32 mask, int timeout)
  88 {
  89         int t = 0;
  90
  91         do {
  92                 if ((iwl_read32(trans, addr) & mask) == (bits & mask))
  93                         return t;
  94                 udelay(IWL_POLL_INTERVAL);
  95                 t += IWL_POLL_INTERVAL;
  96         } while (t < timeout);
  97
  98         return -ETIMEDOUT;
  99 }
 100 EXPORT_SYMBOL_GPL(iwl_poll_bit);
 101
 102 int iwl_grab_nic_access_silent(struct iwl_trans *trans)
 103 {
 104         int ret;
 105
 106         lockdep_assert_held(&trans->reg_lock);
 107
 108         /* this bit wakes up the NIC */
 109         __iwl_set_bit(trans, CSR_GP_CNTRL,
 110                       CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 111
 112         /*
 113          * These bits say the device is running, and should keep running for
 114          * at least a short while (at least as long as MAC_ACCESS_REQ stays 1),
 115          * but they do not indicate that embedded SRAM is restored yet;
 116          * 3945 and 4965 have volatile SRAM, and must save/restore contents
 117          * to/from host DRAM when sleeping/waking for power-saving.
 118          * Each direction takes approximately 1/4 millisecond; with this
 119          * overhead, it's a good idea to grab and hold MAC_ACCESS_REQUEST if a
 120          * series of register accesses are expected (e.g. reading Event Log),
 121          * to keep device from sleeping.
 122          *
 123          * CSR_UCODE_DRV_GP1 register bit MAC_SLEEP == 0 indicates that
 124          * SRAM is okay/restored.  We don't check that here because this call
 125          * is just for hardware register access; but GP1 MAC_SLEEP check is a
 126          * good idea before accessing 3945/4965 SRAM (e.g. reading Event Log).
 127          *
 128          * 5000 series and later (including 1000 series) have non-volatile SRAM,
 129          * and do not save/restore SRAM when power cycling.
 130          */
 131         ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
 132                            CSR_GP_CNTRL_REG_VAL_MAC_ACCESS_EN,
 133                            (CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY |
 134                             CSR_GP_CNTRL_REG_FLAG_GOING_TO_SLEEP), 15000);
 135         if (ret < 0) {
 136                 iwl_write32(trans, CSR_RESET, CSR_RESET_REG_FLAG_FORCE_NMI);
 137                 return -EIO;
 138         }
 139
 140         return 0;
 141 }
 142 EXPORT_SYMBOL_GPL(iwl_grab_nic_access_silent);
 143
 144 bool iwl_grab_nic_access(struct iwl_trans *trans)
 145 {
 146         int ret = iwl_grab_nic_access_silent(trans);
 147         if (unlikely(ret)) {
 148                 u32 val = iwl_read32(trans, CSR_GP_CNTRL);
 149                 WARN_ONCE(1, "Timeout waiting for hardware access "
 150                              "(CSR_GP_CNTRL 0x%08x)\n", val);
 151                 return false;
 152         }
 153
 154         return true;
 155 }
 156 EXPORT_SYMBOL_GPL(iwl_grab_nic_access);
 157
 158 void iwl_release_nic_access(struct iwl_trans *trans)
 159 {
 160         lockdep_assert_held(&trans->reg_lock);
 161         __iwl_clear_bit(trans, CSR_GP_CNTRL,
 162                         CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 163         /*
 164          * Above we read the CSR_GP_CNTRL register, which will flush
 165          * any previous writes, but we need the write that clears the
 166          * MAC_ACCESS_REQ bit to be performed before any other writes
 167          * scheduled on different CPUs (after we drop reg_lock).
 168          */
 169         mmiowb();
 170 }
 171 EXPORT_SYMBOL_GPL(iwl_release_nic_access);
 172
 173 u32 iwl_read_direct32(struct iwl_trans *trans, u32 reg)
 174 {
 175         u32 value;
 176         unsigned long flags;
 177
 178         spin_lock_irqsave(&trans->reg_lock, flags);
 179         iwl_grab_nic_access(trans);
 180         value = iwl_read32(trans, reg);
 181         iwl_release_nic_access(trans);
 182         spin_unlock_irqrestore(&trans->reg_lock, flags);
 183
 184         return value;
 185 }
 186 EXPORT_SYMBOL_GPL(iwl_read_direct32);
 187
 188 void iwl_write_direct32(struct iwl_trans *trans, u32 reg, u32 value)
 189 {
 190         unsigned long flags;
 191
 192         spin_lock_irqsave(&trans->reg_lock, flags);
 193         if (likely(iwl_grab_nic_access(trans))) {
 194                 iwl_write32(trans, reg, value);
 195                 iwl_release_nic_access(trans);
 196         }
 197         spin_unlock_irqrestore(&trans->reg_lock, flags);
 198 }
 199 EXPORT_SYMBOL_GPL(iwl_write_direct32);
 200
 201 int iwl_poll_direct_bit(struct iwl_trans *trans, u32 addr, u32 mask,
 202                         int timeout)
 203 {
 204         int t = 0;
 205
 206         do {
 207                 if ((iwl_read_direct32(trans, addr) & mask) == mask)
 208                         return t;
 209                 udelay(IWL_POLL_INTERVAL);
 210                 t += IWL_POLL_INTERVAL;
 211         } while (t < timeout);
 212
 213         return -ETIMEDOUT;
 214 }
 215 EXPORT_SYMBOL_GPL(iwl_poll_direct_bit);
 216
 217 static inline u32 __iwl_read_prph(struct iwl_trans *trans, u32 ofs)
 218 {
 219         u32 val = iwl_trans_read_prph(trans, ofs);
 220         trace_iwlwifi_dev_ioread_prph32(trans->dev, ofs, val);
 221         return val;
 222 }
 223
 224 static inline void __iwl_write_prph(struct iwl_trans *trans, u32 ofs, u32 val)
 225 {
 226         trace_iwlwifi_dev_iowrite_prph32(trans->dev, ofs, val);
 227         iwl_trans_write_prph(trans, ofs, val);
 228 }
 229
 230 u32 iwl_read_prph(struct iwl_trans *trans, u32 ofs)
 231 {
 232         unsigned long flags;
 233         u32 val;
 234
 235         spin_lock_irqsave(&trans->reg_lock, flags);
 236         iwl_grab_nic_access(trans);
 237         val = __iwl_read_prph(trans, ofs);
 238         iwl_release_nic_access(trans);
 239         spin_unlock_irqrestore(&trans->reg_lock, flags);
 240         return val;
 241 }
 242 EXPORT_SYMBOL_GPL(iwl_read_prph);
 243
 244 void iwl_write_prph(struct iwl_trans *trans, u32 ofs, u32 val)
 245 {
 246         unsigned long flags;
 247
 248         spin_lock_irqsave(&trans->reg_lock, flags);
 249         if (likely(iwl_grab_nic_access(trans))) {
 250                 __iwl_write_prph(trans, ofs, val);
 251                 iwl_release_nic_access(trans);
 252         }
 253         spin_unlock_irqrestore(&trans->reg_lock, flags);
 254 }
 255 EXPORT_SYMBOL_GPL(iwl_write_prph);
 256
 257 void iwl_set_bits_prph(struct iwl_trans *trans, u32 ofs, u32 mask)
 258 {
 259         unsigned long flags;
 260
 261         spin_lock_irqsave(&trans->reg_lock, flags);
 262         if (likely(iwl_grab_nic_access(trans))) {
 263                 __iwl_write_prph(trans, ofs,
 264                                  __iwl_read_prph(trans, ofs) | mask);
 265                 iwl_release_nic_access(trans);
 266         }
 267         spin_unlock_irqrestore(&trans->reg_lock, flags);
 268 }
 269 EXPORT_SYMBOL_GPL(iwl_set_bits_prph);
 270
 271 void iwl_set_bits_mask_prph(struct iwl_trans *trans, u32 ofs,
 272                             u32 bits, u32 mask)
 273 {
 274         unsigned long flags;
 275
 276         spin_lock_irqsave(&trans->reg_lock, flags);
 277         if (likely(iwl_grab_nic_access(trans))) {
 278                 __iwl_write_prph(trans, ofs,
 279                                  (__iwl_read_prph(trans, ofs) & mask) | bits);
 280                 iwl_release_nic_access(trans);
 281         }
 282         spin_unlock_irqrestore(&trans->reg_lock, flags);
 283 }
 284 EXPORT_SYMBOL_GPL(iwl_set_bits_mask_prph);
 285
 286 void iwl_clear_bits_prph(struct iwl_trans *trans, u32 ofs, u32 mask)
 287 {
 288         unsigned long flags;
 289         u32 val;
 290
 291         spin_lock_irqsave(&trans->reg_lock, flags);
 292         if (likely(iwl_grab_nic_access(trans))) {
 293                 val = __iwl_read_prph(trans, ofs);
 294                 __iwl_write_prph(trans, ofs, (val & ~mask));
 295                 iwl_release_nic_access(trans);
 296         }
 297         spin_unlock_irqrestore(&trans->reg_lock, flags);
 298 }
 299 EXPORT_SYMBOL_GPL(iwl_clear_bits_prph);
 300
 301 void _iwl_read_targ_mem_dwords(struct iwl_trans *trans, u32 addr,
 302                                void *buf, int dwords)
 303 {
 304         unsigned long flags;
 305         int offs;
 306         u32 *vals = buf;
 307
 308         spin_lock_irqsave(&trans->reg_lock, flags);
 309         if (likely(iwl_grab_nic_access(trans))) {
 310                 iwl_write32(trans, HBUS_TARG_MEM_RADDR, addr);
 311                 for (offs = 0; offs < dwords; offs++)
 312                         vals[offs] = iwl_read32(trans, HBUS_TARG_MEM_RDAT);
 313                 iwl_release_nic_access(trans);
 314         }
 315         spin_unlock_irqrestore(&trans->reg_lock, flags);
 316 }
 317 EXPORT_SYMBOL_GPL(_iwl_read_targ_mem_dwords);
 318
 319 u32 iwl_read_targ_mem(struct iwl_trans *trans, u32 addr)
 320 {
 321         u32 value;
 322
 323         _iwl_read_targ_mem_dwords(trans, addr, &value, 1);
 324
 325         return value;
 326 }
 327 EXPORT_SYMBOL_GPL(iwl_read_targ_mem);
 328
 329 int _iwl_write_targ_mem_dwords(struct iwl_trans *trans, u32 addr,
 330                                const void *buf, int dwords)
 331 {
 332         unsigned long flags;
 333         int offs, result = 0;
 334         const u32 *vals = buf;
 335
 336         spin_lock_irqsave(&trans->reg_lock, flags);
 337         if (likely(iwl_grab_nic_access(trans))) {
 338                 iwl_write32(trans, HBUS_TARG_MEM_WADDR, addr);
 339                 for (offs = 0; offs < dwords; offs++)
 340                         iwl_write32(trans, HBUS_TARG_MEM_WDAT, vals[offs]);
 341                 iwl_release_nic_access(trans);
 342         } else
 343                 result = -EBUSY;
 344         spin_unlock_irqrestore(&trans->reg_lock, flags);
 345
 346         return result;
 347 }
 348 EXPORT_SYMBOL_GPL(_iwl_write_targ_mem_dwords);
 349
 350 int iwl_write_targ_mem(struct iwl_trans *trans, u32 addr, u32 val)
 351 {
 352         return _iwl_write_targ_mem_dwords(trans, addr, &val, 1);
 353 }
 354 EXPORT_SYMBOL_GPL(iwl_write_targ_mem);