1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11 
  12 /*
  13  * Copyright 2018 Joyent, Inc.
  14  * Copyright 2017 Tegile Systems, Inc.  All rights reserved.
  15  */
  16 
  17 /*
  18  * -------------------------
  19  * Interrupt Handling Theory
  20  * -------------------------
  21  *
  22  * There are a couple different sets of interrupts that we need to worry about:
  23  *
  24  *   - Interrupts from receive queues
  25  *   - Interrupts from transmit queues
  26  *   - 'Other Interrupts', such as the administrative queue
  27  *
  28  * 'Other Interrupts' are asynchronous events such as a link status change event
  29  * being posted to the administrative queue, unrecoverable ECC errors, and more.
  30  * If we have something being posted to the administrative queue, then we go
  31  * through and process it, because it's generally enabled as a separate logical
  32  * interrupt. Note, we may need to do more here eventually. To re-enable the
  33  * interrupts from the 'Other Interrupts' section, we need to clear the PBA and
  34  * write ENA to PFINT_ICR0.
  35  *
  36  * Interrupts from the transmit and receive queues indicates that our requests
  37  * have been processed. In the rx case, it means that we have data that we
  38  * should take a look at and send up the stack. In the tx case, it means that
  39  * data which we got from MAC has now been sent out on the wire and we can free
  40  * the associated data. Most of the logic for acting upon the presence of this
  41  * data can be found in i40e_transciever.c which handles all of the DMA, rx, and
  42  * tx operations. This file is dedicated to handling and dealing with interrupt
  43  * processing.
  44  *
  45  * All devices supported by this driver support three kinds of interrupts:
  46  *
  47  *   o Extended Message Signaled Interrupts (MSI-X)
  48  *   o Message Signaled Interrupts (MSI)
  49  *   o Legacy PCI interrupts (INTx)
  50  *
  51  * Generally speaking the hardware logically handles MSI and INTx the same and
  52  * restricts us to only using a single interrupt, which isn't the interesting
  53  * case. With MSI-X available, each physical function of the device provides the
  54  * opportunity for multiple interrupts which is what we'll focus on.
  55  *
  56  * --------------------
  57  * Interrupt Management
  58  * --------------------
  59  *
  60  * By default, the admin queue, which consists of the asynchronous other
  61  * interrupts is always bound to MSI-X vector zero. Next, we spread out all of
  62  * the other interrupts that we have available to us over the remaining
  63  * interrupt vectors.
  64  *
  65  * This means that there may be multiple queues, both tx and rx, which are
  66  * mapped to the same interrupt. When the interrupt fires, we'll have to check
  67  * all of them for servicing, before we go through and indicate that the
  68  * interrupt is claimed.
  69  *
  70  * The hardware provides the means of mapping various queues to MSI-X interrupts
  71  * by programming the I40E_QINT_RQCTL() and I4OE_QINT_TQCTL() registers. These
  72  * registers can also be used to enable and disable whether or not the queue is
  73  * a source of interrupts. As part of this, the hardware requires that we
  74  * maintain a linked list of queues for each interrupt vector. While it may seem
  75  * like this is only there for the purproses of ITRs, that's not the case. The
  76  * first queue must be programmed in I40E_QINT_LNKLSTN(%vector) register. Each
  77  * queue defines the next one in either the I40E_QINT_RQCTL or I40E_QINT_TQCTL
  78  * register.
  79  *
  80  * Finally, the individual interrupt vector itself has the ability to be enabled
  81  * and disabled. The overall interrupt is controlled through the
  82  * I40E_PFINT_DYN_CTLN() register. This is used to turn on and off the interrupt
  83  * as a whole.
  84  *
  85  * Note that this means that both the individual queue and the interrupt as a
  86  * whole can be toggled and re-enabled.
  87  *
  88  * -------------------
  89  * Non-MSIX Management
  90  * -------------------
  91  *
  92  * We may have a case where the Operating System is unable to actually allocate
  93  * any MSI-X to the system. In such a world, there is only one transmit/receive
  94  * queue pair and it is bound to the same interrupt with index zero. The
  95  * hardware doesn't allow us access to additional interrupt vectors in these
  96  * modes. Note that technically we could support more transmit/receive queues if
  97  * we wanted.
  98  *
  99  * In this world, because the interrupts for the admin queue and traffic are
 100  * mixed together, we have to consult ICR0 to determine what has occurred. The
 101  * QINT_TQCTL and QINT_RQCTL registers have a field, 'MSI-X 0 index' which
 102  * allows us to set a specific bit in ICR0. There are up to seven such bits;
 103  * however, we only use the bit 0 and 1 for the rx and tx queue respectively.
 104  * These are contained by the I40E_INTR_NOTX_{R|T}X_QUEUE and
 105  * I40E_INTR_NOTX_{R|T}X_MASK registers respectively.
 106  *
 107  * Unfortunately, these corresponding queue bits have no corresponding entry in
 108  * the ICR0_ENA register. So instead, when enabling interrupts on the queues, we
 109  * end up enabling it on the queue registers rather than on the MSI-X registers.
 110  * In the MSI-X world, because they can be enabled and disabled, this is
 111  * different and the queues can always be enabled and disabled, but the
 112  * interrupts themselves are toggled (ignoring the question of interrupt
 113  * blanking for polling on rings).
 114  *
 115  * Finally, we still have to set up the interrupt linked list, but the list is
 116  * instead rooted at the register I40E_PFINT_LNKLST0, rather than being tied to
 117  * one of the other MSI-X registers.
 118  *
 119  * --------------------
 120  * Interrupt Moderation
 121  * --------------------
 122  *
 123  * The XL710 hardware has three different interrupt moderation registers per
 124  * interrupt. Unsurprisingly, we use these for:
 125  *
 126  *   o RX interrupts
 127  *   o TX interrupts
 128  *   o 'Other interrupts' (link status change, admin queue, etc.)
 129  *
 130  * By default, we throttle 'other interrupts' the most, then TX interrupts, and
 131  * then RX interrupts. The default values for these were based on trying to
 132  * reason about both the importance and frequency of events. Generally speaking
 133  * 'other interrupts' are not very frequent and they're not important for the
 134  * I/O data path in and of itself (though they may indicate issues with the I/O
 135  * data path).
 136  *
 137  * On the flip side, when we're not polling, RX interrupts are very important.
 138  * The longer we wait for them, the more latency that we inject into the system.
 139  * However, if we allow interrupts to occur too frequently, we risk a few
 140  * problems:
 141  *
 142  *  1) Abusing system resources. Without proper interrupt blanking and polling,
 143  *     we can see upwards of 200k-300k interrupts per second on the system.
 144  *
 145  *  2) Not enough data coalescing to enable polling. In other words, the more
 146  *     data that we allow to build up, the more likely we'll be able to enable
 147  *     polling mode and allowing us to better handle bulk data.
 148  *
 149  * In-between the 'other interrupts' and the TX interrupts we have the
 150  * reclamation of TX buffers. This operation is not quite as important as we
 151  * generally size the ring large enough that we should be able to reclaim a
 152  * substantial amount of the descriptors that we have used per interrupt. So
 153  * while it's important that this interrupt occur, we don't necessarily need it
 154  * firing as frequently as RX; it doesn't, on its own, induce additional latency
 155  * into the system.
 156  *
 157  * Based on all this we currently assign static ITR values for the system. While
 158  * we could move to a dynamic system (the hardware supports that), we'd want to
 159  * make sure that we're seeing problems from this that we believe would be
 160  * generally helped by the added complexity.
 161  *
 162  * Based on this, the default values that we have allow for the following
 163  * interrupt thresholds:
 164  *
 165  *    o 20k interrupts/s for RX
 166  *    o 5k interrupts/s for TX
 167  *    o 2k interupts/s for 'Other Interrupts'
 168  */
 169 
 170 #include "i40e_sw.h"
 171 
 172 #define I40E_INTR_NOTX_QUEUE    0
 173 #define I40E_INTR_NOTX_INTR     0
 174 #define I40E_INTR_NOTX_RX_QUEUE 0
 175 #define I40E_INTR_NOTX_RX_MASK  (1 << I40E_PFINT_ICR0_QUEUE_0_SHIFT)
 176 #define I40E_INTR_NOTX_TX_QUEUE 1
 177 #define I40E_INTR_NOTX_TX_MASK  (1 << I40E_PFINT_ICR0_QUEUE_1_SHIFT)
 178 
 179 void
 180 i40e_intr_set_itr(i40e_t *i40e, i40e_itr_index_t itr, uint_t val)
 181 {
 182         int i;
 183         i40e_hw_t *hw = &i40e->i40e_hw_space;
 184 
 185         VERIFY3U(val, <=, I40E_MAX_ITR);
 186         VERIFY3U(itr, <, I40E_ITR_INDEX_NONE);
 187 
 188         /*
 189          * No matter the interrupt mode, the ITR for other interrupts is always
 190          * on interrupt zero and the same is true if we're not using MSI-X.
 191          */
 192         if (itr == I40E_ITR_INDEX_OTHER ||
 193             i40e->i40e_intr_type != DDI_INTR_TYPE_MSIX) {
 194                 I40E_WRITE_REG(hw, I40E_PFINT_ITR0(itr), val);
 195                 return;
 196         }
 197 
 198         for (i = 0; i < i40e->i40e_num_trqpairs; i++) {
 199                 I40E_WRITE_REG(hw, I40E_PFINT_ITRN(itr, i), val);
 200         }
 201 }
 202 
 203 /*
 204  * Re-enable the adminq. Note that the adminq doesn't have a traditional queue
 205  * associated with it from an interrupt perspective and just lives on ICR0.
 206  * However when MSI-X interrupts are not being used, then this also enables and
 207  * disables those interrupts.
 208  */
 209 static void
 210 i40e_intr_adminq_enable(i40e_t *i40e)
 211 {
 212         i40e_hw_t *hw = &i40e->i40e_hw_space;
 213         uint32_t reg;
 214 
 215         reg = I40E_PFINT_DYN_CTL0_INTENA_MASK |
 216             I40E_PFINT_DYN_CTL0_CLEARPBA_MASK |
 217             (I40E_ITR_INDEX_NONE << I40E_PFINT_DYN_CTL0_ITR_INDX_SHIFT);
 218         I40E_WRITE_REG(hw, I40E_PFINT_DYN_CTL0, reg);
 219         i40e_flush(hw);
 220 }
 221 
 222 static void
 223 i40e_intr_adminq_disable(i40e_t *i40e)
 224 {
 225         i40e_hw_t *hw = &i40e->i40e_hw_space;
 226         uint32_t reg;
 227 
 228         reg = I40E_ITR_INDEX_NONE << I40E_PFINT_DYN_CTL0_ITR_INDX_SHIFT;
 229         I40E_WRITE_REG(hw, I40E_PFINT_DYN_CTL0, reg);
 230 }
 231 
 232 /*
 233  * The next two functions enable/disable the reception of interrupts
 234  * on the given vector. Only vectors 1..N are programmed by these
 235  * functions; vector 0 is special and handled by a different register.
 236  * We must subtract one from the vector because i40e implicitly adds
 237  * one to the vector value. See section 10.2.2.10.13 for more details.
 238  */
 239 static void
 240 i40e_intr_io_enable(i40e_t *i40e, int vector)
 241 {
 242         uint32_t reg;
 243         i40e_hw_t *hw = &i40e->i40e_hw_space;
 244 
 245         ASSERT3S(vector, >, 0);
 246         reg = I40E_PFINT_DYN_CTLN_INTENA_MASK |
 247             I40E_PFINT_DYN_CTLN_CLEARPBA_MASK |
 248             (I40E_ITR_INDEX_NONE << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT);
 249         I40E_WRITE_REG(hw, I40E_PFINT_DYN_CTLN(vector - 1), reg);
 250 }
 251 
 252 static void
 253 i40e_intr_io_disable(i40e_t *i40e, int vector)
 254 {
 255         uint32_t reg;
 256         i40e_hw_t *hw = &i40e->i40e_hw_space;
 257 
 258         ASSERT3S(vector, >, 0);
 259         reg = I40E_ITR_INDEX_NONE << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT;
 260         I40E_WRITE_REG(hw, I40E_PFINT_DYN_CTLN(vector - 1), reg);
 261 }
 262 
 263 /*
 264  * When MSI-X interrupts are being used, then we can enable the actual
 265  * interrupts themselves. However, when they are not, we instead have to turn
 266  * towards the queue's CAUSE_ENA bit and enable that.
 267  */
 268 void
 269 i40e_intr_io_enable_all(i40e_t *i40e)
 270 {
 271         if (i40e->i40e_intr_type == DDI_INTR_TYPE_MSIX) {
 272                 int i;
 273 
 274                 for (i = 1; i < i40e->i40e_intr_count; i++) {
 275                         i40e_intr_io_enable(i40e, i);
 276                 }
 277         } else {
 278                 uint32_t reg;
 279                 i40e_hw_t *hw = &i40e->i40e_hw_space;
 280 
 281                 reg = I40E_READ_REG(hw, I40E_QINT_RQCTL(I40E_INTR_NOTX_QUEUE));
 282                 reg |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
 283                 I40E_WRITE_REG(hw, I40E_QINT_RQCTL(I40E_INTR_NOTX_QUEUE), reg);
 284 
 285                 reg = I40E_READ_REG(hw, I40E_QINT_TQCTL(I40E_INTR_NOTX_QUEUE));
 286                 reg |= I40E_QINT_TQCTL_CAUSE_ENA_MASK;
 287                 I40E_WRITE_REG(hw, I40E_QINT_TQCTL(I40E_INTR_NOTX_QUEUE), reg);
 288         }
 289 }
 290 
 291 /*
 292  * When MSI-X interrupts are being used, then we can disable the actual
 293  * interrupts themselves. However, when they are not, we instead have to turn
 294  * towards the queue's CAUSE_ENA bit and disable that.
 295  */
 296 void
 297 i40e_intr_io_disable_all(i40e_t *i40e)
 298 {
 299         if (i40e->i40e_intr_type == DDI_INTR_TYPE_MSIX) {
 300                 int i;
 301 
 302                 for (i = 1; i < i40e->i40e_intr_count; i++) {
 303                         i40e_intr_io_disable(i40e, i);
 304                 }
 305         } else {
 306                 uint32_t reg;
 307                 i40e_hw_t *hw = &i40e->i40e_hw_space;
 308 
 309                 reg = I40E_READ_REG(hw, I40E_QINT_RQCTL(I40E_INTR_NOTX_QUEUE));
 310                 reg &= ~I40E_QINT_RQCTL_CAUSE_ENA_MASK;
 311                 I40E_WRITE_REG(hw, I40E_QINT_RQCTL(I40E_INTR_NOTX_QUEUE), reg);
 312 
 313                 reg = I40E_READ_REG(hw, I40E_QINT_TQCTL(I40E_INTR_NOTX_QUEUE));
 314                 reg &= ~I40E_QINT_TQCTL_CAUSE_ENA_MASK;
 315                 I40E_WRITE_REG(hw, I40E_QINT_TQCTL(I40E_INTR_NOTX_QUEUE), reg);
 316         }
 317 }
 318 
 319 /*
 320  * As part of disabling the tx and rx queue's we're technically supposed to
 321  * remove the linked list entries. The simplest way is to clear the LNKLSTN
 322  * register by setting it to I40E_QUEUE_TYPE_EOL (0x7FF).
 323  *
 324  * Note all of the FM register access checks are performed by the caller.
 325  */
 326 void
 327 i40e_intr_io_clear_cause(i40e_t *i40e)
 328 {
 329         int i;
 330         i40e_hw_t *hw = &i40e->i40e_hw_space;
 331 
 332         if (i40e->i40e_intr_type != DDI_INTR_TYPE_MSIX) {
 333                 uint32_t reg;
 334                 reg = I40E_QUEUE_TYPE_EOL;
 335                 I40E_WRITE_REG(hw, I40E_PFINT_LNKLST0, reg);
 336                 return;
 337         }
 338 
 339         for (i = 0; i < i40e->i40e_num_trqpairs; i++) {
 340                 uint32_t reg;
 341 #ifdef DEBUG
 342                 /*
 343                  * Verify that the interrupt in question is disabled. This is a
 344                  * prerequisite of modifying the data in question.
 345                  */
 346                 reg = I40E_READ_REG(hw, I40E_PFINT_DYN_CTLN(i));
 347                 VERIFY0(reg & I40E_PFINT_DYN_CTLN_INTENA_MASK);
 348 #endif
 349                 reg = I40E_QUEUE_TYPE_EOL;
 350                 I40E_WRITE_REG(hw, I40E_PFINT_LNKLSTN(i), reg);
 351         }
 352 
 353         i40e_flush(hw);
 354 }
 355 
 356 /*
 357  * Finalize interrupt handling. Mostly this disables the admin queue.
 358  */
 359 void
 360 i40e_intr_chip_fini(i40e_t *i40e)
 361 {
 362 #ifdef DEBUG
 363         int i;
 364         uint32_t reg;
 365 
 366         i40e_hw_t *hw = &i40e->i40e_hw_space;
 367 
 368         /*
 369          * Take a look and verify that all other interrupts have been disabled
 370          * and the interrupt linked lists have been zeroed.
 371          */
 372         if (i40e->i40e_intr_type == DDI_INTR_TYPE_MSIX) {
 373                 for (i = 0; i < i40e->i40e_num_trqpairs; i++) {
 374                         reg = I40E_READ_REG(hw, I40E_PFINT_DYN_CTLN(i));
 375                         VERIFY0(reg & I40E_PFINT_DYN_CTLN_INTENA_MASK);
 376 
 377                         reg = I40E_READ_REG(hw, I40E_PFINT_LNKLSTN(i));
 378                         VERIFY3U(reg, ==, I40E_QUEUE_TYPE_EOL);
 379                 }
 380         }
 381 #endif
 382 
 383         i40e_intr_adminq_disable(i40e);
 384 }
 385 
 386 /*
 387  * Set the head of the interrupt linked list. The PFINT_LNKLSTN[N]
 388  * register actually refers to the 'N + 1' interrupt vector. E.g.,
 389  * PFINT_LNKLSTN[0] refers to interrupt vector 1.
 390  */
 391 static void
 392 i40e_set_lnklstn(i40e_t *i40e, uint_t vector, uint_t queue)
 393 {
 394         uint32_t        reg;
 395         i40e_hw_t       *hw = &i40e->i40e_hw_space;
 396 
 397         reg = (queue << I40E_PFINT_LNKLSTN_FIRSTQ_INDX_SHIFT) |
 398             (I40E_QUEUE_TYPE_RX << I40E_PFINT_LNKLSTN_FIRSTQ_TYPE_SHIFT);
 399 
 400         I40E_WRITE_REG(hw, I40E_PFINT_LNKLSTN(vector), reg);
 401         DEBUGOUT2("PFINT_LNKLSTN[%u] = 0x%x", vector, reg);
 402 }
 403 
 404 /*
 405  * Set the QINT_RQCTL[queue] register. The next queue is always the Tx
 406  * queue associated with this Rx queue. Unlike PFINT_LNKLSTN, the
 407  * vector should be the actual vector this queue is on -- i.e., it
 408  * should be equal to itrq_rx_intrvec.
 409  */
 410 static void
 411 i40e_set_rqctl(i40e_t *i40e, uint_t vector, uint_t queue)
 412 {
 413         uint32_t        reg;
 414         i40e_hw_t       *hw = &i40e->i40e_hw_space;
 415 
 416         ASSERT3U(vector, ==, i40e->i40e_trqpairs[queue].itrq_rx_intrvec);
 417 
 418         reg = (vector << I40E_QINT_RQCTL_MSIX_INDX_SHIFT) |
 419             (I40E_ITR_INDEX_RX << I40E_QINT_RQCTL_ITR_INDX_SHIFT) |
 420             (queue << I40E_QINT_RQCTL_NEXTQ_INDX_SHIFT) |
 421             (I40E_QUEUE_TYPE_TX << I40E_QINT_RQCTL_NEXTQ_TYPE_SHIFT) |
 422             I40E_QINT_RQCTL_CAUSE_ENA_MASK;
 423 
 424         I40E_WRITE_REG(hw, I40E_QINT_RQCTL(queue), reg);
 425         DEBUGOUT2("QINT_RQCTL[%u] = 0x%x", queue, reg);
 426 }
 427 
 428 /*
 429  * Like i40e_set_rqctl(), but for QINT_TQCTL[queue]. The next queue is
 430  * either the Rx queue of another TRQP, or EOL.
 431  */
 432 static void
 433 i40e_set_tqctl(i40e_t *i40e, uint_t vector, uint_t queue, uint_t next_queue)
 434 {
 435         uint32_t        reg;
 436         i40e_hw_t       *hw = &i40e->i40e_hw_space;
 437 
 438         ASSERT3U(vector, ==, i40e->i40e_trqpairs[queue].itrq_tx_intrvec);
 439 
 440         reg = (vector << I40E_QINT_TQCTL_MSIX_INDX_SHIFT) |
 441             (I40E_ITR_INDEX_TX << I40E_QINT_TQCTL_ITR_INDX_SHIFT) |
 442             (next_queue << I40E_QINT_TQCTL_NEXTQ_INDX_SHIFT) |
 443             (I40E_QUEUE_TYPE_RX << I40E_QINT_TQCTL_NEXTQ_TYPE_SHIFT) |
 444             I40E_QINT_TQCTL_CAUSE_ENA_MASK;
 445 
 446         I40E_WRITE_REG(hw, I40E_QINT_TQCTL(queue), reg);
 447         DEBUGOUT2("QINT_TQCTL[%u] = 0x%x", queue, reg);
 448 }
 449 
 450 /*
 451  * Program the interrupt linked list. Each vector has a linked list of
 452  * queues which act as event sources for that vector. When one of
 453  * those sources has an event the associated interrupt vector is
 454  * fired. This mapping must match the mapping found in
 455  * i40e_map_intrs_to_vectors().
 456  *
 457  * See section 7.5.3 for more information about the configuration of
 458  * the interrupt linked list.
 459  */
 460 static void
 461 i40e_intr_init_queue_msix(i40e_t *i40e)
 462 {
 463         uint_t intr_count;
 464 
 465         /*
 466          * The 0th vector is for 'Other Interrupts' only (subject to
 467          * change in the future).
 468          */
 469         intr_count = i40e->i40e_intr_count - 1;
 470 
 471         for (uint_t vec = 0; vec < intr_count; vec++) {
 472                 boolean_t head = B_TRUE;
 473 
 474                 for (uint_t qidx = vec; qidx < i40e->i40e_num_trqpairs;
 475                      qidx += intr_count) {
 476                         uint_t next_qidx = qidx + intr_count;
 477 
 478                         next_qidx = (next_qidx > i40e->i40e_num_trqpairs) ?
 479                             I40E_QUEUE_TYPE_EOL : next_qidx;
 480 
 481                         if (head) {
 482                                 i40e_set_lnklstn(i40e, vec, qidx);
 483                                 head = B_FALSE;
 484                         }
 485 
 486                         i40e_set_rqctl(i40e, vec + 1, qidx);
 487                         i40e_set_tqctl(i40e, vec + 1, qidx, next_qidx);
 488                 }
 489         }
 490 }
 491 
 492 /*
 493  * Set up a single queue to share the admin queue interrupt in the non-MSI-X
 494  * world. Note we do not enable the queue as an interrupt cause at this time. We
 495  * don't have any other vector of control here, unlike with the MSI-X interrupt
 496  * case.
 497  */
 498 static void
 499 i40e_intr_init_queue_shared(i40e_t *i40e)
 500 {
 501         i40e_hw_t *hw = &i40e->i40e_hw_space;
 502         uint32_t reg;
 503 
 504         VERIFY(i40e->i40e_intr_type == DDI_INTR_TYPE_FIXED ||
 505             i40e->i40e_intr_type == DDI_INTR_TYPE_MSI);
 506 
 507         reg = (I40E_INTR_NOTX_QUEUE << I40E_PFINT_LNKLST0_FIRSTQ_INDX_SHIFT) |
 508             (I40E_QUEUE_TYPE_RX << I40E_PFINT_LNKLSTN_FIRSTQ_TYPE_SHIFT);
 509         I40E_WRITE_REG(hw, I40E_PFINT_LNKLST0, reg);
 510 
 511         reg = (I40E_INTR_NOTX_INTR << I40E_QINT_RQCTL_MSIX_INDX_SHIFT) |
 512             (I40E_ITR_INDEX_RX << I40E_QINT_RQCTL_ITR_INDX_SHIFT) |
 513             (I40E_INTR_NOTX_RX_QUEUE << I40E_QINT_RQCTL_MSIX0_INDX_SHIFT) |
 514             (I40E_INTR_NOTX_QUEUE << I40E_QINT_RQCTL_NEXTQ_INDX_SHIFT) |
 515             (I40E_QUEUE_TYPE_TX << I40E_QINT_RQCTL_NEXTQ_TYPE_SHIFT);
 516 
 517         I40E_WRITE_REG(hw, I40E_QINT_RQCTL(I40E_INTR_NOTX_QUEUE), reg);
 518 
 519         reg = (I40E_INTR_NOTX_INTR << I40E_QINT_TQCTL_MSIX_INDX_SHIFT) |
 520             (I40E_ITR_INDEX_TX << I40E_QINT_TQCTL_ITR_INDX_SHIFT) |
 521             (I40E_INTR_NOTX_TX_QUEUE << I40E_QINT_TQCTL_MSIX0_INDX_SHIFT) |
 522             (I40E_QUEUE_TYPE_EOL << I40E_QINT_TQCTL_NEXTQ_INDX_SHIFT) |
 523             (I40E_QUEUE_TYPE_RX << I40E_QINT_TQCTL_NEXTQ_TYPE_SHIFT);
 524 
 525         I40E_WRITE_REG(hw, I40E_QINT_TQCTL(I40E_INTR_NOTX_QUEUE), reg);
 526 }
 527 
 528 /*
 529  * Enable the specified queue as a valid source of interrupts. Note, this should
 530  * only be used as part of the GLDv3's interrupt blanking routines. The debug
 531  * build assertions are specific to that.
 532  */
 533 void
 534 i40e_intr_rx_queue_enable(i40e_trqpair_t *itrq)
 535 {
 536         uint32_t reg;
 537         uint_t queue = itrq->itrq_index;
 538         i40e_hw_t *hw = &itrq->itrq_i40e->i40e_hw_space;
 539 
 540         ASSERT(MUTEX_HELD(&itrq->itrq_rx_lock));
 541         ASSERT(queue < itrq->itrq_i40e->i40e_num_trqpairs);
 542 
 543         reg = I40E_READ_REG(hw, I40E_QINT_RQCTL(queue));
 544         ASSERT0(reg & I40E_QINT_RQCTL_CAUSE_ENA_MASK);
 545         reg |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
 546         I40E_WRITE_REG(hw, I40E_QINT_RQCTL(queue), reg);
 547 }
 548 
 549 /*
 550  * Disable the specified queue as a valid source of interrupts. Note, this
 551  * should only be used as part of the GLDv3's interrupt blanking routines. The
 552  * debug build assertions are specific to that.
 553  */
 554 void
 555 i40e_intr_rx_queue_disable(i40e_trqpair_t *itrq)
 556 {
 557         uint32_t reg;
 558         uint_t queue = itrq->itrq_index;
 559         i40e_hw_t *hw = &itrq->itrq_i40e->i40e_hw_space;
 560 
 561         ASSERT(MUTEX_HELD(&itrq->itrq_rx_lock));
 562         ASSERT(queue < itrq->itrq_i40e->i40e_num_trqpairs);
 563 
 564         reg = I40E_READ_REG(hw, I40E_QINT_RQCTL(queue));
 565         ASSERT3U(reg & I40E_QINT_RQCTL_CAUSE_ENA_MASK, ==,
 566             I40E_QINT_RQCTL_CAUSE_ENA_MASK);
 567         reg &= ~I40E_QINT_RQCTL_CAUSE_ENA_MASK;
 568         I40E_WRITE_REG(hw, I40E_QINT_RQCTL(queue), reg);
 569 }
 570 
 571 /*
 572  * Start up the various chip's interrupt handling. We not only configure the
 573  * adminq here, but we also go through and configure all of the actual queues,
 574  * the interrupt linked lists, and others.
 575  */
 576 void
 577 i40e_intr_chip_init(i40e_t *i40e)
 578 {
 579         i40e_hw_t *hw = &i40e->i40e_hw_space;
 580         uint32_t reg;
 581 
 582         /*
 583          * Ensure that all non adminq interrupts are disabled at the chip level.
 584          */
 585         i40e_intr_io_disable_all(i40e);
 586 
 587         I40E_WRITE_REG(hw, I40E_PFINT_ICR0_ENA, 0);
 588         (void) I40E_READ_REG(hw, I40E_PFINT_ICR0);
 589 
 590         /*
 591          * Always enable all of the other-class interrupts to be on their own
 592          * ITR. This only needs to be set on interrupt zero, which has its own
 593          * special setting.
 594          */
 595         reg = I40E_ITR_INDEX_OTHER << I40E_PFINT_STAT_CTL0_OTHER_ITR_INDX_SHIFT;
 596         I40E_WRITE_REG(hw, I40E_PFINT_STAT_CTL0, reg);
 597 
 598         /*
 599          * Enable interrupt types we expect to receive. At the moment, this
 600          * is limited to the adminq; however, we'll want to review 11.2.2.9.22
 601          * for more types here as we add support for detecting them, handling
 602          * them, and resetting the device as appropriate.
 603          */
 604         reg = I40E_PFINT_ICR0_ENA_ADMINQ_MASK;
 605         I40E_WRITE_REG(hw, I40E_PFINT_ICR0_ENA, reg);
 606 
 607         /*
 608          * Always set the interrupt linked list to empty. We'll come back and
 609          * change this if MSI-X are actually on the scene.
 610          */
 611         I40E_WRITE_REG(hw, I40E_PFINT_LNKLST0, I40E_QUEUE_TYPE_EOL);
 612 
 613         i40e_intr_adminq_enable(i40e);
 614 
 615         /*
 616          * Set up all of the queues and map them to interrupts based on the bit
 617          * assignments.
 618          */
 619         if (i40e->i40e_intr_type == DDI_INTR_TYPE_MSIX) {
 620                 i40e_intr_init_queue_msix(i40e);
 621         } else {
 622                 i40e_intr_init_queue_shared(i40e);
 623         }
 624 
 625         /*
 626          * Finally set all of the default ITRs for the interrupts. Note that the
 627          * queues will have been set up above.
 628          */
 629         i40e_intr_set_itr(i40e, I40E_ITR_INDEX_RX, i40e->i40e_rx_itr);
 630         i40e_intr_set_itr(i40e, I40E_ITR_INDEX_TX, i40e->i40e_tx_itr);
 631         i40e_intr_set_itr(i40e, I40E_ITR_INDEX_OTHER, i40e->i40e_other_itr);
 632 }
 633 
 634 static void
 635 i40e_intr_adminq_work(i40e_t *i40e)
 636 {
 637         struct i40e_hw *hw = &i40e->i40e_hw_space;
 638         struct i40e_arq_event_info evt;
 639         uint16_t remain = 1;
 640 
 641         bzero(&evt, sizeof (struct i40e_arq_event_info));
 642         evt.buf_len = I40E_ADMINQ_BUFSZ;
 643         evt.msg_buf = i40e->i40e_aqbuf;
 644 
 645         while (remain != 0) {
 646                 enum i40e_status_code ret;
 647                 uint16_t opcode;
 648 
 649                 /*
 650                  * At the moment, the only error code that seems to be returned
 651                  * is one saying that there's no work. In such a case we leave
 652                  * this be.
 653                  */
 654                 ret = i40e_clean_arq_element(hw, &evt, &remain);
 655                 if (ret != I40E_SUCCESS)
 656                         break;
 657 
 658                 opcode = LE_16(evt.desc.opcode);
 659                 switch (opcode) {
 660                 /*
 661                  * Disable link checks for NEX-6977. With the fibers unplugged
 662                  * we can end up receiving too many link check interrupts,
 663                  * saturating one CPU for each link. This can cause system hangs
 664                  * at boot or shutdown when the system is running single-threaded.
 665                  *
 666                  * case i40e_aqc_opc_get_link_status:
 667                  *      mutex_enter(&i40e->i40e_general_lock);
 668                  *      i40e_link_check(i40e);
 669                  *      mutex_exit(&i40e->i40e_general_lock);
 670                  *      break;
 671                  */
 672                 default:
 673                         /*
 674                          * Longer term we'll want to enable other causes here
 675                          * and get these cleaned up and doing something.
 676                          */
 677                         break;
 678                 }
 679         }
 680 }
 681 
 682 static void
 683 i40e_intr_rx_work(i40e_t *i40e, i40e_trqpair_t *itrq)
 684 {
 685         mblk_t *mp = NULL;
 686 
 687         mutex_enter(&itrq->itrq_rx_lock);
 688         if (!itrq->itrq_intr_poll)
 689                 mp = i40e_ring_rx(itrq, I40E_POLL_NULL);
 690         mutex_exit(&itrq->itrq_rx_lock);
 691 
 692         if (mp == NULL)
 693                 return;
 694 
 695         mac_rx_ring(i40e->i40e_mac_hdl, itrq->itrq_macrxring, mp,
 696             itrq->itrq_rxgen);
 697 }
 698 
 699 /* ARGSUSED */
 700 static void
 701 i40e_intr_tx_work(i40e_t *i40e, i40e_trqpair_t *itrq)
 702 {
 703         i40e_tx_recycle_ring(itrq);
 704 }
 705 
 706 /*
 707  * At the moment, the only 'other' interrupt on ICR0 that we handle is the
 708  * adminq. We should go through and support the other notifications at some
 709  * point.
 710  */
 711 static void
 712 i40e_intr_other_work(i40e_t *i40e)
 713 {
 714         struct i40e_hw *hw = &i40e->i40e_hw_space;
 715         uint32_t reg;
 716 
 717         reg = I40E_READ_REG(hw, I40E_PFINT_ICR0);
 718         if (i40e_check_acc_handle(i40e->i40e_osdep_space.ios_reg_handle) !=
 719             DDI_FM_OK) {
 720                 ddi_fm_service_impact(i40e->i40e_dip, DDI_SERVICE_DEGRADED);
 721                 atomic_or_32(&i40e->i40e_state, I40E_ERROR);
 722                 return;
 723         }
 724 
 725         if (reg & I40E_PFINT_ICR0_ADMINQ_MASK)
 726                 i40e_intr_adminq_work(i40e);
 727 
 728         /*
 729          * Make sure that the adminq interrupt is not masked and then explicitly
 730          * enable the adminq and thus the other interrupt.
 731          */
 732         reg = I40E_READ_REG(hw, I40E_PFINT_ICR0_ENA);
 733         reg |= I40E_PFINT_ICR0_ENA_ADMINQ_MASK;
 734         I40E_WRITE_REG(hw, I40E_PFINT_ICR0_ENA, reg);
 735 
 736         i40e_intr_adminq_enable(i40e);
 737 }
 738 
 739 /*
 740  * Handle an MSI-X interrupt. See section 7.5.1.3 for an overview of
 741  * the MSI-X interrupt sequence.
 742  */
 743 uint_t
 744 i40e_intr_msix(void *arg1, void *arg2)
 745 {
 746         i40e_t *i40e = (i40e_t *)arg1;
 747         uint_t vector_idx = (uint_t)(uintptr_t)arg2;
 748 
 749         ASSERT3U(vector_idx, <, i40e->i40e_intr_count);
 750 
 751         /*
 752          * When using MSI-X interrupts, vector 0 is always reserved for the
 753          * adminq at this time. Though longer term, we'll want to also bridge
 754          * some I/O to them.
 755          */
 756         if (vector_idx == 0) {
 757                 i40e_intr_other_work(i40e);
 758                 return (DDI_INTR_CLAIMED);
 759         }
 760 
 761         ASSERT3U(vector_idx, >, 0);
 762 
 763         /*
 764          * We determine the queue indexes via simple arithmetic (as
 765          * opposed to keeping explicit state like a bitmap). While
 766          * conveinent, it does mean that i40e_map_intrs_to_vectors(),
 767          * i40e_intr_init_queue_msix(), and this function must be
 768          * modified as a unit.
 769          *
 770          * We subtract 1 from the vector to offset the addition we
 771          * performed during i40e_map_intrs_to_vectors().
 772          */
 773         for (uint_t i = vector_idx - 1; i < i40e->i40e_num_trqpairs;
 774              i += (i40e->i40e_intr_count - 1)) {
 775                 i40e_trqpair_t *itrq = &i40e->i40e_trqpairs[i];
 776 
 777                 ASSERT3U(i, <, i40e->i40e_num_trqpairs);
 778                 ASSERT3P(itrq, !=, NULL);
 779                 i40e_intr_rx_work(i40e, itrq);
 780                 i40e_intr_tx_work(i40e, itrq);
 781         }
 782 
 783         i40e_intr_io_enable(i40e, vector_idx);
 784         return (DDI_INTR_CLAIMED);
 785 }
 786 
 787 static uint_t
 788 i40e_intr_notx(i40e_t *i40e, boolean_t shared)
 789 {
 790         i40e_hw_t *hw = &i40e->i40e_hw_space;
 791         uint32_t reg;
 792         i40e_trqpair_t *itrq = &i40e->i40e_trqpairs[0];
 793         int ret = DDI_INTR_CLAIMED;
 794 
 795         if (shared == B_TRUE) {
 796                 mutex_enter(&i40e->i40e_general_lock);
 797                 if (i40e->i40e_state & I40E_SUSPENDED) {
 798                         mutex_exit(&i40e->i40e_general_lock);
 799                         return (DDI_INTR_UNCLAIMED);
 800                 }
 801                 mutex_exit(&i40e->i40e_general_lock);
 802         }
 803 
 804         reg = I40E_READ_REG(hw, I40E_PFINT_ICR0);
 805         if (i40e_check_acc_handle(i40e->i40e_osdep_space.ios_reg_handle) !=
 806             DDI_FM_OK) {
 807                 ddi_fm_service_impact(i40e->i40e_dip, DDI_SERVICE_DEGRADED);
 808                 atomic_or_32(&i40e->i40e_state, I40E_ERROR);
 809                 return (DDI_INTR_CLAIMED);
 810         }
 811 
 812         if (reg == 0) {
 813                 if (shared == B_TRUE)
 814                         ret = DDI_INTR_UNCLAIMED;
 815                 goto done;
 816         }
 817 
 818         if (reg & I40E_PFINT_ICR0_ADMINQ_MASK)
 819                 i40e_intr_adminq_work(i40e);
 820 
 821         if (reg & I40E_INTR_NOTX_RX_MASK)
 822                 i40e_intr_rx_work(i40e, itrq);
 823 
 824         if (reg & I40E_INTR_NOTX_TX_MASK)
 825                 i40e_intr_tx_work(i40e, itrq);
 826 
 827 done:
 828         i40e_intr_adminq_enable(i40e);
 829         return (ret);
 830 
 831 }
 832 
 833 /* ARGSUSED */
 834 uint_t
 835 i40e_intr_msi(void *arg1, void *arg2)
 836 {
 837         i40e_t *i40e = (i40e_t *)arg1;
 838 
 839         return (i40e_intr_notx(i40e, B_FALSE));
 840 }
 841 
 842 /* ARGSUSED */
 843 uint_t
 844 i40e_intr_legacy(void *arg1, void *arg2)
 845 {
 846         i40e_t *i40e = (i40e_t *)arg1;
 847 
 848         return (i40e_intr_notx(i40e, B_TRUE));
 849 }