drivers/net/wireless/ath/wil6210/interrupt.c

   1 /*
   2  * Copyright (c) 2012 Qualcomm Atheros, Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <linux/interrupt.h>
  18
  19 #include "wil6210.h"
  20 #include "trace.h"
  21
  22 /**
  23  * Theory of operation:
  24  *
  25  * There is ISR pseudo-cause register,
  26  * dma_rgf->DMA_RGF.PSEUDO_CAUSE.PSEUDO_CAUSE
  27  * Its bits represents OR'ed bits from 3 real ISR registers:
  28  * TX, RX, and MISC.
  29  *
  30  * Registers may be configured to either "write 1 to clear" or
  31  * "clear on read" mode
  32  *
  33  * When handling interrupt, one have to mask/unmask interrupts for the
  34  * real ISR registers, or hardware may malfunction.
  35  *
  36  */
  37
  38 #define WIL6210_IRQ_DISABLE     (0xFFFFFFFFUL)
  39 #define WIL6210_IMC_RX          BIT_DMA_EP_RX_ICR_RX_DONE
  40 #define WIL6210_IMC_TX          (BIT_DMA_EP_TX_ICR_TX_DONE | \
  41                                 BIT_DMA_EP_TX_ICR_TX_DONE_N(0))
  42 #define WIL6210_IMC_MISC        (ISR_MISC_FW_READY | \
  43                                  ISR_MISC_MBOX_EVT | \
  44                                  ISR_MISC_FW_ERROR)
  45
  46 #define WIL6210_IRQ_PSEUDO_MASK (u32)(~(BIT_DMA_PSEUDO_CAUSE_RX | \
  47                                         BIT_DMA_PSEUDO_CAUSE_TX | \
  48                                         BIT_DMA_PSEUDO_CAUSE_MISC))
  49
  50 #if defined(CONFIG_WIL6210_ISR_COR)
  51 /* configure to Clear-On-Read mode */
  52 #define WIL_ICR_ICC_VALUE       (0xFFFFFFFFUL)
  53
  54 static inline void wil_icr_clear(u32 x, void __iomem *addr)
  55 {
  56 }
  57 #else /* defined(CONFIG_WIL6210_ISR_COR) */
  58 /* configure to Write-1-to-Clear mode */
  59 #define WIL_ICR_ICC_VALUE       (0UL)
  60
  61 static inline void wil_icr_clear(u32 x, void __iomem *addr)
  62 {
  63         iowrite32(x, addr);
  64 }
  65 #endif /* defined(CONFIG_WIL6210_ISR_COR) */
  66
  67 static inline u32 wil_ioread32_and_clear(void __iomem *addr)
  68 {
  69         u32 x = ioread32(addr);
  70
  71         wil_icr_clear(x, addr);
  72
  73         return x;
  74 }
  75
  76 static void wil6210_mask_irq_tx(struct wil6210_priv *wil)
  77 {
  78         iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
  79                   HOSTADDR(RGF_DMA_EP_TX_ICR) +
  80                   offsetof(struct RGF_ICR, IMS));
  81 }
  82
  83 static void wil6210_mask_irq_rx(struct wil6210_priv *wil)
  84 {
  85         iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
  86                   HOSTADDR(RGF_DMA_EP_RX_ICR) +
  87                   offsetof(struct RGF_ICR, IMS));
  88 }
  89
  90 static void wil6210_mask_irq_misc(struct wil6210_priv *wil)
  91 {
  92         iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
  93                   HOSTADDR(RGF_DMA_EP_MISC_ICR) +
  94                   offsetof(struct RGF_ICR, IMS));
  95 }
  96
  97 static void wil6210_mask_irq_pseudo(struct wil6210_priv *wil)
  98 {
  99         wil_dbg_irq(wil, "%s()\n", __func__);
 100
 101         iowrite32(WIL6210_IRQ_DISABLE, wil->csr +
 102                   HOSTADDR(RGF_DMA_PSEUDO_CAUSE_MASK_SW));
 103
 104         clear_bit(wil_status_irqen, &wil->status);
 105 }
 106
 107 void wil6210_unmask_irq_tx(struct wil6210_priv *wil)
 108 {
 109         iowrite32(WIL6210_IMC_TX, wil->csr +
 110                   HOSTADDR(RGF_DMA_EP_TX_ICR) +
 111                   offsetof(struct RGF_ICR, IMC));
 112 }
 113
 114 void wil6210_unmask_irq_rx(struct wil6210_priv *wil)
 115 {
 116         iowrite32(WIL6210_IMC_RX, wil->csr +
 117                   HOSTADDR(RGF_DMA_EP_RX_ICR) +
 118                   offsetof(struct RGF_ICR, IMC));
 119 }
 120
 121 static void wil6210_unmask_irq_misc(struct wil6210_priv *wil)
 122 {
 123         iowrite32(WIL6210_IMC_MISC, wil->csr +
 124                   HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 125                   offsetof(struct RGF_ICR, IMC));
 126 }
 127
 128 static void wil6210_unmask_irq_pseudo(struct wil6210_priv *wil)
 129 {
 130         wil_dbg_irq(wil, "%s()\n", __func__);
 131
 132         set_bit(wil_status_irqen, &wil->status);
 133
 134         iowrite32(WIL6210_IRQ_PSEUDO_MASK, wil->csr +
 135                   HOSTADDR(RGF_DMA_PSEUDO_CAUSE_MASK_SW));
 136 }
 137
 138 void wil6210_disable_irq(struct wil6210_priv *wil)
 139 {
 140         wil_dbg_irq(wil, "%s()\n", __func__);
 141
 142         wil6210_mask_irq_tx(wil);
 143         wil6210_mask_irq_rx(wil);
 144         wil6210_mask_irq_misc(wil);
 145         wil6210_mask_irq_pseudo(wil);
 146 }
 147
 148 void wil6210_enable_irq(struct wil6210_priv *wil)
 149 {
 150         wil_dbg_irq(wil, "%s()\n", __func__);
 151
 152         iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_RX_ICR) +
 153                   offsetof(struct RGF_ICR, ICC));
 154         iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_TX_ICR) +
 155                   offsetof(struct RGF_ICR, ICC));
 156         iowrite32(WIL_ICR_ICC_VALUE, wil->csr + HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 157                   offsetof(struct RGF_ICR, ICC));
 158
 159         /* interrupt moderation parameters */
 160         if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
 161                 /* disable interrupt moderation for monitor
 162                  * to get better timestamp precision
 163                  */
 164                 iowrite32(0, wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_CRL));
 165         } else {
 166                 iowrite32(WIL6210_ITR_TRSH,
 167                           wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_TRSH));
 168                 iowrite32(BIT_DMA_ITR_CNT_CRL_EN,
 169                           wil->csr + HOSTADDR(RGF_DMA_ITR_CNT_CRL));
 170         }
 171
 172         wil6210_unmask_irq_pseudo(wil);
 173         wil6210_unmask_irq_tx(wil);
 174         wil6210_unmask_irq_rx(wil);
 175         wil6210_unmask_irq_misc(wil);
 176 }
 177
 178 static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
 179 {
 180         struct wil6210_priv *wil = cookie;
 181         u32 isr = wil_ioread32_and_clear(wil->csr +
 182                                          HOSTADDR(RGF_DMA_EP_RX_ICR) +
 183                                          offsetof(struct RGF_ICR, ICR));
 184
 185         trace_wil6210_irq_rx(isr);
 186         wil_dbg_irq(wil, "ISR RX 0x%08x\n", isr);
 187
 188         if (!isr) {
 189                 wil_err(wil, "spurious IRQ: RX\n");
 190                 return IRQ_NONE;
 191         }
 192
 193         wil6210_mask_irq_rx(wil);
 194
 195         if (isr & BIT_DMA_EP_RX_ICR_RX_DONE) {
 196                 wil_dbg_irq(wil, "RX done\n");
 197                 isr &= ~BIT_DMA_EP_RX_ICR_RX_DONE;
 198                 wil_dbg_txrx(wil, "NAPI schedule\n");
 199                 napi_schedule(&wil->napi_rx);
 200         }
 201
 202         if (isr)
 203                 wil_err(wil, "un-handled RX ISR bits 0x%08x\n", isr);
 204
 205         /* Rx IRQ will be enabled when NAPI processing finished */
 206
 207         return IRQ_HANDLED;
 208 }
 209
 210 static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
 211 {
 212         struct wil6210_priv *wil = cookie;
 213         u32 isr = wil_ioread32_and_clear(wil->csr +
 214                                          HOSTADDR(RGF_DMA_EP_TX_ICR) +
 215                                          offsetof(struct RGF_ICR, ICR));
 216
 217         trace_wil6210_irq_tx(isr);
 218         wil_dbg_irq(wil, "ISR TX 0x%08x\n", isr);
 219
 220         if (!isr) {
 221                 wil_err(wil, "spurious IRQ: TX\n");
 222                 return IRQ_NONE;
 223         }
 224
 225         wil6210_mask_irq_tx(wil);
 226
 227         if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
 228                 wil_dbg_irq(wil, "TX done\n");
 229                 napi_schedule(&wil->napi_tx);
 230                 isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
 231                 /* clear also all VRING interrupts */
 232                 isr &= ~(BIT(25) - 1UL);
 233         }
 234
 235         if (isr)
 236                 wil_err(wil, "un-handled TX ISR bits 0x%08x\n", isr);
 237
 238         /* Tx IRQ will be enabled when NAPI processing finished */
 239
 240         return IRQ_HANDLED;
 241 }
 242
 243 static void wil_notify_fw_error(struct wil6210_priv *wil)
 244 {
 245         struct device *dev = &wil_to_ndev(wil)->dev;
 246         char *envp[3] = {
 247                 [0] = "SOURCE=wil6210",
 248                 [1] = "EVENT=FW_ERROR",
 249                 [2] = NULL,
 250         };
 251         kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
 252 }
 253
 254 static void wil_cache_mbox_regs(struct wil6210_priv *wil)
 255 {
 256         /* make shadow copy of registers that should not change on run time */
 257         wil_memcpy_fromio_32(&wil->mbox_ctl, wil->csr + HOST_MBOX,
 258                              sizeof(struct wil6210_mbox_ctl));
 259         wil_mbox_ring_le2cpus(&wil->mbox_ctl.rx);
 260         wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx);
 261 }
 262
 263 static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
 264 {
 265         struct wil6210_priv *wil = cookie;
 266         u32 isr = wil_ioread32_and_clear(wil->csr +
 267                                          HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 268                                          offsetof(struct RGF_ICR, ICR));
 269
 270         trace_wil6210_irq_misc(isr);
 271         wil_dbg_irq(wil, "ISR MISC 0x%08x\n", isr);
 272
 273         if (!isr) {
 274                 wil_err(wil, "spurious IRQ: MISC\n");
 275                 return IRQ_NONE;
 276         }
 277
 278         wil6210_mask_irq_misc(wil);
 279
 280         if (isr & ISR_MISC_FW_ERROR) {
 281                 wil_err(wil, "Firmware error detected\n");
 282                 clear_bit(wil_status_fwready, &wil->status);
 283                 /*
 284                  * do not clear @isr here - we do 2-nd part in thread
 285                  * there, user space get notified, and it should be done
 286                  * in non-atomic context
 287                  */
 288         }
 289
 290         if (isr & ISR_MISC_FW_READY) {
 291                 wil_dbg_irq(wil, "IRQ: FW ready\n");
 292                 wil_cache_mbox_regs(wil);
 293                 set_bit(wil_status_reset_done, &wil->status);
 294                 /**
 295                  * Actual FW ready indicated by the
 296                  * WMI_FW_READY_EVENTID
 297                  */
 298                 isr &= ~ISR_MISC_FW_READY;
 299         }
 300
 301         wil->isr_misc = isr;
 302
 303         if (isr) {
 304                 return IRQ_WAKE_THREAD;
 305         } else {
 306                 wil6210_unmask_irq_misc(wil);
 307                 return IRQ_HANDLED;
 308         }
 309 }
 310
 311 static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
 312 {
 313         struct wil6210_priv *wil = cookie;
 314         u32 isr = wil->isr_misc;
 315
 316         trace_wil6210_irq_misc_thread(isr);
 317         wil_dbg_irq(wil, "Thread ISR MISC 0x%08x\n", isr);
 318
 319         if (isr & ISR_MISC_FW_ERROR) {
 320                 wil_notify_fw_error(wil);
 321                 isr &= ~ISR_MISC_FW_ERROR;
 322         }
 323
 324         if (isr & ISR_MISC_MBOX_EVT) {
 325                 wil_dbg_irq(wil, "MBOX event\n");
 326                 wmi_recv_cmd(wil);
 327                 isr &= ~ISR_MISC_MBOX_EVT;
 328         }
 329
 330         if (isr)
 331                 wil_err(wil, "un-handled MISC ISR bits 0x%08x\n", isr);
 332
 333         wil->isr_misc = 0;
 334
 335         wil6210_unmask_irq_misc(wil);
 336
 337         return IRQ_HANDLED;
 338 }
 339
 340 /**
 341  * thread IRQ handler
 342  */
 343 static irqreturn_t wil6210_thread_irq(int irq, void *cookie)
 344 {
 345         struct wil6210_priv *wil = cookie;
 346
 347         wil_dbg_irq(wil, "Thread IRQ\n");
 348         /* Discover real IRQ cause */
 349         if (wil->isr_misc)
 350                 wil6210_irq_misc_thread(irq, cookie);
 351
 352         wil6210_unmask_irq_pseudo(wil);
 353
 354         return IRQ_HANDLED;
 355 }
 356
 357 /* DEBUG
 358  * There is subtle bug in hardware that causes IRQ to raise when it should be
 359  * masked. It is quite rare and hard to debug.
 360  *
 361  * Catch irq issue if it happens and print all I can.
 362  */
 363 static int wil6210_debug_irq_mask(struct wil6210_priv *wil, u32 pseudo_cause)
 364 {
 365         if (!test_bit(wil_status_irqen, &wil->status)) {
 366                 u32 icm_rx = wil_ioread32_and_clear(wil->csr +
 367                                 HOSTADDR(RGF_DMA_EP_RX_ICR) +
 368                                 offsetof(struct RGF_ICR, ICM));
 369                 u32 icr_rx = wil_ioread32_and_clear(wil->csr +
 370                                 HOSTADDR(RGF_DMA_EP_RX_ICR) +
 371                                 offsetof(struct RGF_ICR, ICR));
 372                 u32 imv_rx = ioread32(wil->csr +
 373                                 HOSTADDR(RGF_DMA_EP_RX_ICR) +
 374                                 offsetof(struct RGF_ICR, IMV));
 375                 u32 icm_tx = wil_ioread32_and_clear(wil->csr +
 376                                 HOSTADDR(RGF_DMA_EP_TX_ICR) +
 377                                 offsetof(struct RGF_ICR, ICM));
 378                 u32 icr_tx = wil_ioread32_and_clear(wil->csr +
 379                                 HOSTADDR(RGF_DMA_EP_TX_ICR) +
 380                                 offsetof(struct RGF_ICR, ICR));
 381                 u32 imv_tx = ioread32(wil->csr +
 382                                 HOSTADDR(RGF_DMA_EP_TX_ICR) +
 383                                 offsetof(struct RGF_ICR, IMV));
 384                 u32 icm_misc = wil_ioread32_and_clear(wil->csr +
 385                                 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 386                                 offsetof(struct RGF_ICR, ICM));
 387                 u32 icr_misc = wil_ioread32_and_clear(wil->csr +
 388                                 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 389                                 offsetof(struct RGF_ICR, ICR));
 390                 u32 imv_misc = ioread32(wil->csr +
 391                                 HOSTADDR(RGF_DMA_EP_MISC_ICR) +
 392                                 offsetof(struct RGF_ICR, IMV));
 393                 wil_err(wil, "IRQ when it should be masked: pseudo 0x%08x\n"
 394                                 "Rx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
 395                                 "Tx   icm:icr:imv 0x%08x 0x%08x 0x%08x\n"
 396                                 "Misc icm:icr:imv 0x%08x 0x%08x 0x%08x\n",
 397                                 pseudo_cause,
 398                                 icm_rx, icr_rx, imv_rx,
 399                                 icm_tx, icr_tx, imv_tx,
 400                                 icm_misc, icr_misc, imv_misc);
 401
 402                 return -EINVAL;
 403         }
 404
 405         return 0;
 406 }
 407
 408 static irqreturn_t wil6210_hardirq(int irq, void *cookie)
 409 {
 410         irqreturn_t rc = IRQ_HANDLED;
 411         struct wil6210_priv *wil = cookie;
 412         u32 pseudo_cause = ioread32(wil->csr + HOSTADDR(RGF_DMA_PSEUDO_CAUSE));
 413
 414         /**
 415          * pseudo_cause is Clear-On-Read, no need to ACK
 416          */
 417         if ((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff))
 418                 return IRQ_NONE;
 419
 420         /* FIXME: IRQ mask debug */
 421         if (wil6210_debug_irq_mask(wil, pseudo_cause))
 422                 return IRQ_NONE;
 423
 424         trace_wil6210_irq_pseudo(pseudo_cause);
 425         wil_dbg_irq(wil, "Pseudo IRQ 0x%08x\n", pseudo_cause);
 426
 427         wil6210_mask_irq_pseudo(wil);
 428
 429         /* Discover real IRQ cause
 430          * There are 2 possible phases for every IRQ:
 431          * - hard IRQ handler called right here
 432          * - threaded handler called later
 433          *
 434          * Hard IRQ handler reads and clears ISR.
 435          *
 436          * If threaded handler requested, hard IRQ handler
 437          * returns IRQ_WAKE_THREAD and saves ISR register value
 438          * for the threaded handler use.
 439          *
 440          * voting for wake thread - need at least 1 vote
 441          */
 442         if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_RX) &&
 443             (wil6210_irq_rx(irq, cookie) == IRQ_WAKE_THREAD))
 444                 rc = IRQ_WAKE_THREAD;
 445
 446         if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_TX) &&
 447             (wil6210_irq_tx(irq, cookie) == IRQ_WAKE_THREAD))
 448                 rc = IRQ_WAKE_THREAD;
 449
 450         if ((pseudo_cause & BIT_DMA_PSEUDO_CAUSE_MISC) &&
 451             (wil6210_irq_misc(irq, cookie) == IRQ_WAKE_THREAD))
 452                 rc = IRQ_WAKE_THREAD;
 453
 454         /* if thread is requested, it will unmask IRQ */
 455         if (rc != IRQ_WAKE_THREAD)
 456                 wil6210_unmask_irq_pseudo(wil);
 457
 458         return rc;
 459 }
 460
 461 static int wil6210_request_3msi(struct wil6210_priv *wil, int irq)
 462 {
 463         int rc;
 464         /*
 465          * IRQ's are in the following order:
 466          * - Tx
 467          * - Rx
 468          * - Misc
 469          */
 470
 471         rc = request_irq(irq, wil6210_irq_tx, IRQF_SHARED,
 472                          WIL_NAME"_tx", wil);
 473         if (rc)
 474                 return rc;
 475
 476         rc = request_irq(irq + 1, wil6210_irq_rx, IRQF_SHARED,
 477                          WIL_NAME"_rx", wil);
 478         if (rc)
 479                 goto free0;
 480
 481         rc = request_threaded_irq(irq + 2, wil6210_irq_misc,
 482                                   wil6210_irq_misc_thread,
 483                                   IRQF_SHARED, WIL_NAME"_misc", wil);
 484         if (rc)
 485                 goto free1;
 486
 487         return 0;
 488         /* error branch */
 489 free1:
 490         free_irq(irq + 1, wil);
 491 free0:
 492         free_irq(irq, wil);
 493
 494         return rc;
 495 }
 496
 497 int wil6210_init_irq(struct wil6210_priv *wil, int irq)
 498 {
 499         int rc;
 500         if (wil->n_msi == 3)
 501                 rc = wil6210_request_3msi(wil, irq);
 502         else
 503                 rc = request_threaded_irq(irq, wil6210_hardirq,
 504                                           wil6210_thread_irq,
 505                                           wil->n_msi ? 0 : IRQF_SHARED,
 506                                           WIL_NAME, wil);
 507         if (rc)
 508                 return rc;
 509
 510         wil6210_enable_irq(wil);
 511
 512         return 0;
 513 }
 514
 515 void wil6210_fini_irq(struct wil6210_priv *wil, int irq)
 516 {
 517         wil6210_disable_irq(wil);
 518         free_irq(irq, wil);
 519         if (wil->n_msi == 3) {
 520                 free_irq(irq + 1, wil);
 521                 free_irq(irq + 2, wil);
 522         }
 523 }